January 2025 Earth Science Regents — Answer Key & Worked Solutions

Every question from the January 2025 Earth Science Regents exam, with the correct answer and a full step-by-step solution. Check your work, learn the method, then convert your raw score.

Practice Earth Science free Score calculator

These are real questions from the January 2025 Earth Science New York State Regents examination, published by NYSED. Worked solutions are written by RegentsLab.

Question 1 · 2 pts

Ceres, a dwarf planet, is located approximately 413 million kilometers from the Sun and is located between the orbits of

(A) Mercury and Venus
(B) Earth and Mars
(C) Mars and Jupiter ✓
(D) Saturn and Uranus

Worked solution

$\text{Ceres orbits within the main asteroid belt}$ The asteroid belt, where Ceres is located, lies between the orbits of Mars and Jupiter.

Answer: Mars and Jupiter

Ceres is the largest object in the main asteroid belt, which lies between the orbits of Mars and Jupiter, consistent with its distance of about 413 million km from the Sun.

Question 2 · 2 pts

Observations made by astronomers indicate that the light from most galaxies shows a

(A) red shift because the galaxies are moving toward Earth
(B) red shift because the galaxies are moving away from Earth ✓
(C) blue shift because the galaxies are moving toward Earth
(D) blue shift because the galaxies are moving away from Earth

Worked solution

$\text{Doppler effect: increased wavelength} \Rightarrow \text{red shift} \Rightarrow \text{recession}$

Answer: red shift because the galaxies are moving away from Earth

Most galaxies show a red shift in their light spectra, indicating they are moving away from Earth, which is evidence for an expanding universe.

Question 3 · 2 pts

Compared to the Jovian planets, the terrestrial planets are

(A) large, gaseous, and of low density
(B) large, gaseous, and of high density
(C) small, rocky, and of low density
(D) small, rocky, and of high density ✓

Worked solution

$\text{Terrestrial planets: Mercury, Venus, Earth, Mars}$ Rocky composition and small size compared to gas giants gives them higher density.

Answer: small, rocky, and of high density

Terrestrial planets are small, rocky worlds with high density, unlike the large, gaseous, low-density Jovian planets.

Question 4 · 2 pts

The apparent shift in the direction of the swing of a Foucault pendulum is a direct result of the

(A) inclination of Earth's axis
(B) spinning of Earth on its axis ✓
(C) orbiting of Earth around the Sun
(D) distance between Earth and the Sun

Worked solution

$\text{Pendulum plane stays fixed; Earth rotates beneath it}$

Answer: spinning of Earth on its axis

A Foucault pendulum appears to change its swing direction because Earth is rotating on its axis beneath the pendulum's fixed plane of motion.

Question 5 · 2 pts

Which motion causes some constellations to be visible in New York State only during winter nights and other constellations to be visible only during summer nights?

(A) rotation of Earth on its axis
(B) revolution of Earth around the Sun ✓
(C) rotation of the constellations around Earth
(D) revolution of the constellations around the Sun

Worked solution

$\text{Earth's revolution changes the night-side view of the sky over a year}$

Answer: revolution of Earth around the Sun

As Earth revolves around the Sun, different portions of the night sky face Earth's dark side in different seasons, so different constellations become visible in winter versus summer.

Question 6 · 2 pts

Which set of New York State locations would have the greatest difference in the altitude of Polaris observed in the night sky?

The altitude of Polaris equals the observer's latitude. Approximate latitudes of these New York State locations (from the Generalized Landscape Regions map in the Earth Science Reference Tables): | Location | Approximate Latitude | |---|---| | Niagara Falls | 43.1 deg N | | Albany | 42.7 deg N | | Rochester | 43.2 deg N | | Ithaca | 42.4 deg N | | Riverhead | 40.9 deg N | | Massena | 44.9 deg N | | Plattsburgh | 44.7 deg N | | Jamestown | 42.1 deg N |

(A) Niagara Falls and Albany
(B) Rochester and Ithaca
(C) Riverhead and Massena ✓
(D) Plattsburgh and Jamestown

Worked solution

$\text{Altitude of Polaris} = \text{observer's latitude}$ The pair of locations with the greatest difference in latitude has the greatest difference in Polaris altitude.

$\text{Riverhead (south) and Massena (far north) have the largest north-south latitude separation in NY State}$

Answer: Riverhead and Massena

The altitude of Polaris above the horizon equals the observer's latitude, so the two NY locations with the greatest latitude difference, Riverhead in the south and Massena in the far north, show the greatest difference in Polaris's altitude.

Question 7 · 2 pts

Which processes of the water cycle allow water vapor to enter the atmosphere?

(A) condensation and evaporation
(B) condensation and infiltration
(C) transpiration and evaporation ✓
(D) transpiration and infiltration

Worked solution

$\text{Evaporation: liquid} \to \text{vapor from surfaces}$

$\text{Transpiration: water vapor released from plants}$

Answer: transpiration and evaporation

Evaporation and transpiration both convert liquid water into water vapor and release it into the atmosphere, while condensation and infiltration remove water vapor or move liquid water, respectively.

Question 8 · 2 pts

What is the dewpoint when the dry-bulb temperature is 19°C and the relative humidity is 73%?

(A) 12°C
(B) 14°C ✓
(C) 3°C
(D) 16°C

Worked solution

$\text{Dry-bulb} = 19^\circ C,\ RH = 73\%$ Using the ESRT Relative Humidity table to find the wet-bulb depression corresponding to 19°C dry-bulb and 73% RH

$\text{Wet-bulb depression} \approx 2^\circ C \Rightarrow \text{wet-bulb} = 17^\circ C$

$\text{Look up Dewpoint table with dry-bulb } 19^\circ C \text{ and depression } 2^\circ C \Rightarrow 14^\circ C$

Answer: 14°C

Using the ESRT relative humidity and dewpoint tables with a dry-bulb temperature of 19°C and a relative humidity of 73%, the corresponding dewpoint is 14°C.

Question 9 · 2 pts

The diagram below shows a weather station model. The station model shows the number 91 in the upper left, the number 150 in the upper right, the number 80 in the lower left, a half-shaded circle (partly cloudy sky symbol), and wind barbs extending to the lower left. What is the air pressure, in millibars (mb), indicated by this station model?

(A) 1015.0 mb ✓
(B) 915.0 mb
(C) 150 mb
(D) 15.0 mb

Worked solution

$\text{Pressure code} = 150$ Station model pressure codes are 3-digit codes representing tenths of millibars, with an implied leading 9 or 10.

$150 < 500 \Rightarrow \text{prepend } 10 \Rightarrow 1015.0$

Answer: 1015.0 mb

Station model pressure codes below 500 are converted by placing a 10 before the number and dividing by 10, so the code 150 represents an actual pressure of 1015.0 mb.

Question 10 · 2 pts

The photograph below was taken by aiming a camera at a portion of the night sky above Albany, New York, for a period of time to record the apparent star motion, resulting in star trails. Which celestial object is located at the center of the star trails?

(A) Polaris ✓
(B) Alpha Centauri
(C) the Sun
(D) the Moon

Worked solution

$\text{Stars appear to circle around the celestial pole}$ Polaris lies very close to the north celestial pole, so it appears nearly stationary at the center of star trails.

Answer: Polaris

Because Polaris is located almost directly above Earth's rotational axis (near the north celestial pole), long-exposure photographs of the night sky show other stars tracing circular trails around it.

Question 11 · 2 pts

The map below shows the locations of four time zones in the United States (Pacific, Mountain, Central, Eastern). Seattle, Washington, and Albany, New York, are labeled on the map. If the time in Albany, New York, is 10 a.m., what time would it be in Seattle, Washington?

(A) 1 p.m.
(B) 12 p.m.
(C) 8 a.m.
(D) 7 a.m. ✓

Worked solution

$\text{Albany is in the Eastern time zone; Seattle is in the Pacific time zone}$

$\text{Pacific time is 3 hours behind Eastern time}$

$10\text{ a.m.} - 3\text{ hours} = 7\text{ a.m.}$

Answer: 7 a.m.

Seattle is in the Pacific time zone, which is three hours behind Albany's Eastern time zone, so 10 a.m. in Albany corresponds to 7 a.m. in Seattle.

Question 12 · 2 pts

Which diagram correctly matches the location of the Sun with the direction of the shadow cast by the stick? Four diagrams (1)-(4) each show a horizon oval labeled with North, East, South, West, a vertical stick standing at the center, a shadow cast from the stick, and the Sun positioned somewhere along an arc above the horizon.

(A) Diagram 1: Sun positioned in the eastern sky above the horizon; shadow drawn extending toward the west-southwest from the stick
(B) Diagram 2: Sun positioned low near the eastern horizon; shadow drawn extending toward the west from the stick ✓
(C) Diagram 3: Sun positioned low near the western horizon; shadow drawn extending toward the east from the stick
(D) Diagram 4: Sun positioned in the southern sky; shadow drawn extending toward the north from the stick, but the Sun and shadow are on the same side

Worked solution

$\text{A shadow is always cast on the side of an object opposite the Sun}$

$\text{Check each diagram: the correct one places the shadow directly opposite the Sun's position along the horizon arc}$

Answer: Diagram 2

A shadow always points in the direction opposite the Sun; only the diagram where the shadow's direction is exactly opposite the Sun's position along the horizon (choice 2 per the scoring key) is geometrically consistent.

Question 13 · 2 pts

The diagrams below, labeled A, B, C, and D, represent fronts associated with a low pressure system (L). Each diagram shows a curved front line with either triangle symbols (cold front) or semicircle symbols (warm front) attached at different stages of merging into a single occluded front line. Which sequence best represents the order in the development of an occluded front from a cold front and warm front?

(A) A, B, C, D
(B) B, A, D, C ✓
(C) C, D, A, B
(D) D, C, B, A

Worked solution

$\text{An occluded front forms when a faster cold front catches up to and overtakes a warm front}$

$\text{Sequence progresses from separate cold and warm fronts to a fully occluded front with both symbols on the same side}$

Answer: B, A, D, C

An occluded front develops in stages as the faster-moving cold front catches up with and lifts the warm front; the scoring key confirms the correct progression is diagram B first, then A, then D, then C.

Question 14 · 2 pts

Which map shows the most likely direction of flow of the jet stream and the types of air masses found on either side? Four maps of the United States are shown, each with a jet stream (a wavy band) crossing the country and labels 'Warm' and 'Cold' on either side, with arrows indicating flow direction.

(A) Map 1: jet stream flows from the Atlantic Ocean toward the Pacific Ocean; Warm labeled north, Cold labeled south
(B) Map 2: jet stream flows from the Pacific Ocean toward the Atlantic Ocean; Cold labeled north, Warm labeled south ✓
(C) Map 3: jet stream flows from the Atlantic Ocean toward the Pacific Ocean; Warm labeled south, Cold labeled north
(D) Map 4: jet stream flows from the Pacific Ocean toward the Atlantic Ocean; Cold labeled south, Warm labeled north

Worked solution

$\text{The jet stream generally flows west to east across the US, from the Pacific toward the Atlantic}$

$\text{Colder air masses lie to the north of the jet stream, warmer air masses lie to the south}$

Answer: Map 2

The polar jet stream typically flows west to east (Pacific to Atlantic) across the United States, separating colder air to the north from warmer air to the south, matching Map 2 as confirmed by the scoring key.

Question 15 · 2 pts

Which statement best explains why predictions for extreme weather events are more accurate today than in the past?

(A) There are fewer extreme weather events occurring now.
(B) Scientists control weather by using technology.
(C) Weather conditions change more slowly now than in the past.
(D) Advanced computer models use weather data to make predictions. ✓

Worked solution

$\text{Improved technology} \Rightarrow \text{better data collection and modeling} \Rightarrow \text{more accurate forecasts}$

Answer: Advanced computer models use weather data to make predictions.

Modern forecasting accuracy has improved mainly because advanced computer models can process large amounts of weather data to generate more reliable predictions.

Question 16 · 2 pts

In order to maximize the amount of insolation absorbed by a roof in a colder climate, roofing materials should be

(A) dark-colored and rough-textured ✓
(B) dark-colored and smooth-textured
(C) light-colored and rough-textured
(D) light-colored and smooth-textured

Worked solution

$\text{Dark colors absorb more insolation than light colors}$

$\text{Rough textures absorb more insolation than smooth (reflective) textures}$

Answer: dark-colored and rough-textured

Dark-colored, rough-textured surfaces absorb the most insolation because dark colors reduce reflection and rough textures scatter and trap incoming radiation, ideal for maximizing heat absorption in a colder climate.

Question 17 · 2 pts

Uneven heating of Earth's surface and atmosphere, along with the Coriolis Effect, produces ocean currents with a general

(A) clockwise flow in both northern and southern hemispheres
(B) counterclockwise flow in both northern and southern hemispheres
(C) clockwise flow in the northern hemisphere and counterclockwise flow in the southern hemisphere ✓
(D) counterclockwise flow in the northern hemisphere and clockwise flow in the southern hemisphere

Worked solution

$\text{Coriolis Effect deflects moving currents right in NH, left in SH}$

$\Rightarrow \text{major ocean gyres circulate clockwise in NH, counterclockwise in SH}$

Answer: clockwise flow in the northern hemisphere and counterclockwise flow in the southern hemisphere

The Coriolis Effect deflects ocean currents to the right in the Northern Hemisphere and to the left in the Southern Hemisphere, producing clockwise gyres in the north and counterclockwise gyres in the south.

Question 18 · 2 pts

Which human activity contributes to the high levels of greenhouse gases in Earth's atmosphere?

(A) burning fossil fuels ✓
(B) watering farm crops
(C) using solar energy
(D) replanting forests

Worked solution

$\text{Combustion of coal, oil, natural gas releases CO}_2 \text{ into the atmosphere}$

Answer: burning fossil fuels

Burning fossil fuels releases large amounts of carbon dioxide, a major greenhouse gas, directly increasing atmospheric greenhouse gas levels.

Question 19 · 2 pts

What is the main reason that locations near oceans have smaller annual temperature ranges than locations inland at the same latitude?

(A) Oceans have a lower elevation than land.
(B) Oceans cover a greater percentage of Earth's surface.
(C) Water has a lower density than land.
(D) Water has a higher specific heat than land. ✓

Worked solution

$\text{High specific heat of water} \Rightarrow \text{slower temperature change for a given amount of heat}$

$\Rightarrow \text{coastal areas experience smaller seasonal temperature swings}$

Answer: Water has a higher specific heat than land.

Water's higher specific heat means it heats up and cools down more slowly than land, moderating temperatures near oceans and producing smaller annual temperature ranges compared to inland areas.

Question 20 · 2 pts

The division of geologic time into eras, periods, and epochs is based primarily on

(A) celestial events
(B) tectonic events
(C) the absolute age of rocks
(D) the fossil record ✓

Worked solution

$\text{Major boundaries in the geologic time scale correspond to major changes/extinctions in fossil assemblages}$

Answer: the fossil record

Geologic time is divided into eras, periods, and epochs based primarily on major changes observed in the fossil record, such as mass extinctions and the appearance of new life forms.

Question 21 · 2 pts

During which geologic time period were thick layers of evaporites deposited in New York State?

(A) Triassic
(B) Permian
(C) Silurian ✓
(D) Pennsylvanian

Worked solution

$\text{ESRT Geologic History of New York chart shows evaporite deposits (e.g., Salina Group, Syracuse area salt/gypsum) during the Silurian Period}$

Answer: Silurian

According to the geologic history of New York State, thick evaporite deposits such as rock salt and gypsum formed during the Silurian Period when shallow seas evaporated.

Question 22 · 2 pts

Earth's outer core is inferred to be a liquid because

(A) P-waves cannot travel through it
(B) S-waves cannot travel through it ✓
(C) P-waves travel faster than S-waves through it
(D) S-waves travel faster than P-waves through it

Worked solution

$\text{S-waves (shear waves) cannot travel through liquids}$

$\text{S-wave shadow zone observed} \Rightarrow \text{outer core is liquid}$

Answer: S-waves cannot travel through it

S-waves cannot travel through liquids, and since S-waves do not pass through Earth's outer core, this is used as evidence that the outer core is liquid.

Question 23 · 2 pts

A seismograph detects an earthquake that occurred 5600 km away. The P-waves arrived at 10:36:00 a.m. What time did the earthquake occur?

(A) 09:00:00 a.m.
(B) 10:19:50 a.m.
(C) 10:27:00 a.m. ✓
(D) 10:45:00 a.m.

Worked solution

$\text{Epicenter distance} = 5600\ \text{km}$ Given distance from seismograph to epicenter

$\text{P-wave travel time} \approx 9\ \text{min } 00\ \text{s}$ Read from the P-wave travel-time curve on the Earthquake P-wave and S-wave Travel Time graph in the Earth Science Reference Tables at 5600 km

$\text{Origin time} = 10{:}36{:}00 - 0{:}09{:}00 = 10{:}27{:}00\ \text{a.m.}$ Subtract the travel time from the arrival time

Answer: 10:27:00 a.m.

The earthquake's origin time is found by subtracting the P-wave travel time (read from the reference tables travel-time graph for a 5600 km distance, about 9 minutes) from the arrival time of the P-waves.

Question 24 · 2 pts

The Mariana Trench has formed because the Pacific Plate is

(A) overriding the Philippine Plate
(B) overriding the Indian-Australian Plate
(C) subducting beneath the Philippine Plate ✓
(D) subducting beneath the Indian-Australian Plate

Worked solution

$\text{Mariana Trench} = \text{deep-ocean trench at a convergent boundary}$

$\text{Denser oceanic Pacific Plate} \rightarrow \text{subducts beneath the Philippine Plate}$

Answer: subducting beneath the Philippine Plate

Deep ocean trenches like the Mariana Trench form where one oceanic plate subducts beneath another; here the Pacific Plate is subducting beneath the Philippine Plate.

Question 25 · 2 pts

Rock primarily composed of which mineral would be most resistant to physical weathering?

(A) calcite
(B) gypsum
(C) halite
(D) olivine ✓

Worked solution

$\text{Hardness (Mohs): gypsum} \approx 2,\ \text{calcite} \approx 3,\ \text{halite} \approx 2.5,\ \text{olivine} \approx 6.5\text{-}7$

$\text{Greater hardness} \Rightarrow \text{greater resistance to physical (mechanical) weathering}$

Answer: olivine

Physical weathering resistance increases with mineral hardness; olivine is by far the hardest of the choices listed, making it the most resistant to physical weathering.

Question 26 · 2 pts

Which agent of erosion produces parallel scratches and grooves in surface bedrock?

(A) glacier ✓
(B) wind
(C) running water
(D) ocean waves

Worked solution

$\text{Glacial ice carries embedded rock debris}$

$\text{Debris dragged over bedrock leaves parallel striations (scratches and grooves)}$

Answer: glacier

As a glacier moves, rock fragments frozen in its base scrape across the underlying bedrock, carving parallel scratches and grooves called striations.

Question 27 · 2 pts

The map below shows the prevailing wind direction over the Sierra Nevada, a mountain range in California. Letters A and B represent locations on Earth's surface. Compared to the climate at location A, the climate at location B generally is

(A) cooler with more precipitation
(B) cooler with less precipitation
(C) warmer with more precipitation
(D) warmer with less precipitation ✓

Worked solution

$\text{Wind blows west to east, from the Pacific Ocean toward Nevada}$

$\text{Location A (windward side): moist air rises, cools, and precipitates}$

$\text{Location B (leeward side): descending dry air warms adiabatically (rain shadow)}$

Answer: warmer with less precipitation

Location A sits on the windward (upwind) side of the Sierra Nevada where rising moist air cools and drops precipitation, while location B is on the leeward (downwind) side, where descending air warms and dries, producing a rain-shadow climate that is warmer with less precipitation.

Question 28 · 2 pts

Which pie graph correctly shows the percentage of original radioactive $^{40}K$ remaining in an igneous rock sample after $2.6 \times 10^9$ years? (Key: shaded = $^{40}K$, white = $^{40}Ar$ and $^{40}Ca$)

(A) Pie graph with about three-fourths shaded ($^{40}K$) and one-fourth white ($^{40}Ar$ and $^{40}Ca$)
(B) Pie graph with half shaded ($^{40}K$) and half white ($^{40}Ar$ and $^{40}Ca$)
(C) Pie graph with about one-fourth shaded ($^{40}K$) and three-fourths white ($^{40}Ar$ and $^{40}Ca$) ✓
(D) Pie graph that is entirely white (0% $^{40}K$ remaining)

Worked solution

$\text{Half-life of } ^{40}K \approx 1.3 \times 10^9\ \text{years (ESRT radioactive decay data)}$

$\dfrac{2.6\times10^9}{1.3\times10^9} = 2\ \text{half-lives elapsed}$

$\text{After 1 half-life: } 50\%\ ^{40}K\ \text{remains}\quad \text{After 2 half-lives: } 25\%\ ^{40}K\ \text{remains}$

Answer: Pie graph with about one-fourth shaded ($^{40}K$) and three-fourths white ($^{40}Ar$ and $^{40}Ca$)

Since 2.6 billion years equals exactly two half-lives of potassium-40 (1.3 billion years each), only 25% of the original $^{40}K$ remains, matching the pie graph shaded about one-fourth.

Question 29 · 2 pts

The diagram below represents three rock outcrops at locations A, B, and C. No overturning of rock layers has occurred. Which rock unit shown in the three outcrops is the oldest?

(A) siltstone layer at the top of location A
(B) shale layer at the bottom of location B ✓
(C) conglomerate layer at the top of location B
(D) limestone layer at the bottom of location C

Worked solution

$\text{Apply the Law of Superposition: lower layers are older than layers above them}$

$\text{Correlate matching layers (e.g., volcanic ash markers, unconformities) between outcrops A, B, and C}$

$\text{Comparing the deepest correlated layers among the four choices, the shale at the bottom of location B lies deepest in the overall sequence}$

Answer: shale layer at the bottom of location B

Using superposition and cross-correlation of marker beds (volcanic ash layers and an unconformity) among the three outcrops, the shale layer at the bottom of location B corresponds to the deepest, and therefore oldest, rock unit among the choices given.

Question 30 · 2 pts

The diagram below represents the magnetic polarity preserved by minerals within the bedrock of the oceanic crust near the Mid-Atlantic Ridge. Letters A, B, C, and D represent locations on the ocean-floor bedrock. The oldest bedrock is found at location

(A) A ✓
(B) B
(C) C
(D) D

Worked solution

$\text{New oceanic crust forms continuously at the Mid-Atlantic Ridge and spreads outward symmetrically}$

$\text{Crust farther from the ridge axis is older than crust closer to the ridge axis}$

$\text{Among the labeled points, location A lies farthest from the ridge axis}$

Answer: A

Because new oceanic crust is continuously created at the mid-ocean ridge and pushed outward as seafloor spreading occurs, bedrock farthest from the ridge crest is the oldest; of the labeled points, location A is farthest from the ridge.

Question 31 · 2 pts

Oswego and Old Forge, located at similar latitudes in New York State, have very different landscapes. Which two factors are primarily responsible for these landscape differences?

(A) soil characteristics and bedrock composition
(B) soil characteristics and bedrock age
(C) bedrock structure and bedrock composition ✓
(D) bedrock structure and bedrock age

Worked solution

$\text{Landscape (surface topography) region in NY depends mainly on underlying bedrock's structure (folded, flat, faulted) and composition (resistant vs. weak rock types)}$

$\text{Oswego lies on flat-lying sedimentary bedrock (Erie-Ontario Lowlands); Old Forge lies on resistant, structurally deformed bedrock (Adirondacks)}$

Answer: bedrock structure and bedrock composition

New York's landscape regions are determined chiefly by the structure and composition of the local bedrock, which explains why Oswego's lowland and Old Forge's highland landscapes differ despite being at a similar latitude.

Question 32 · 2 pts

The topographic map below shows the location of Henry Creek. Points A, B, C, and D represent locations on Earth's surface. Contour Interval = 10 feet. At which location would the water in Henry Creek be flowing at the greatest rate?

(A) A
(B) B
(C) C ✓
(D) D

Worked solution

$\text{Stream flow rate increases with steeper gradient (slope)}$

$\text{Steeper gradient is shown on a topographic map by more closely spaced contour lines}$

$\text{Contour lines crossing Henry Creek are closest together near point C}$

Answer: C

A stream flows fastest where its gradient is steepest, which on a topographic map is shown by the most closely spaced contour lines; near point C the contour lines crossing Henry Creek are closest together, indicating the steepest slope and fastest flow.

Question 33 · 2 pts

A metamorphic rock with banding is described as having a

(A) clastic texture
(B) non-clastic texture
(C) foliated texture ✓
(D) non-foliated texture

Worked solution

$\text{Banding in metamorphic rock results from parallel alignment of mineral grains under directed pressure}$

$\text{This banded, layered appearance defines a foliated texture}$

Answer: foliated texture

Banding in a metamorphic rock is the visible result of mineral grains being aligned in parallel bands by directed pressure, which is the definition of a foliated texture.

Question 34 · 2 pts

The hardness of a mineral is primarily a result of the mineral's

(A) mass
(B) nonmetallic shape
(C) pattern of breakage
(D) internal arrangement of atoms ✓

Worked solution

$\text{Hardness depends on the strength and spacing of chemical bonds between atoms in the crystal lattice}$

$\text{This bonding arises from the mineral's internal atomic arrangement, not its mass or shape}$

Answer: internal arrangement of atoms

A mineral's hardness is determined by how tightly and regularly its atoms are bonded together in its internal crystal structure, not by its mass, external shape, or breakage pattern.

Question 35 · 2 pts

Two sedimentary rocks formed from organic sediments are

(A) bituminous coal and limestone ✓
(B) bituminous coal and anthracite coal
(C) rock gypsum and limestone
(D) rock gypsum and anthracite coal

Worked solution

$\text{Organic sedimentary rocks form from accumulated remains of living organisms}$

$\text{Bituminous coal forms from compacted plant material; limestone (e.g., coquina/some fossiliferous limestone) forms from shell/organic carbonate debris}$

$\text{Anthracite coal is metamorphic, not sedimentary; rock gypsum is a chemical/evaporite sedimentary rock, not organic}$

Answer: bituminous coal and limestone

Bituminous coal and limestone are both classified as organic sedimentary rocks (formed from plant material and shell/organic debris, respectively), whereas anthracite coal is metamorphic and rock gypsum is a chemical (evaporite) sedimentary rock.

Question 36 · 2 pts

Bouvet Island is the most remote uninhabited island in the world. It is located above a geologic hot spot on the Southwest Indian Ridge. The closest landmass to the island is Antarctica, which is 1700 km away. Most of this volcanic island is currently covered by glaciers. Scientists inferred from drill core samples that the last massive lava flow that occurred on Bouvet Island was approximately 2000 years ago. The distance between Bouvet Island and Antarctica is approximately equal to the distance from Earth's surface to the

(A) top of the asthenosphere
(B) middle of the stiffer mantle ✓
(C) bottom of the outer core
(D) center of Earth

Worked solution

$\text{ESRT Inferred Properties of Earth's Interior: stiffer mantle (mesosphere) extends from about 350 km to 2900 km depth}$

$\text{Midpoint of stiffer mantle} \approx \dfrac{350+2900}{2} \approx 1625\ \text{km, close to } 1700\ \text{km}$

Answer: middle of the stiffer mantle

A depth of 1700 km falls roughly at the midpoint of the stiffer mantle layer (mesosphere) shown in the Earth Science Reference Tables' Earth's interior diagram, so the 1700 km surface distance to Antarctica is comparable to that depth.

Question 37 · 2 pts

Which cross section best represents the mantle convection currents formed beneath the Bouvet hot spot?

(A) Cross section 1: convection cell arrows shown circulating in one arrangement beneath the hot spot
(B) Cross section 2: convection cell arrows show two adjacent cells rising together beneath the hot spot and sinking outward at both far ends ✓
(C) Cross section 3: convection cell arrows shown circulating in another arrangement beneath the hot spot
(D) Cross section 4: convection cell arrows shown circulating in another arrangement beneath the hot spot

Worked solution

$\text{A hot spot marks a rising mantle plume, so material must be moving upward directly beneath it}$

$\text{Adjacent convection cells should diverge from beneath the hot spot and sink at the outer edges of the diagram}$

Answer: Cross section 2

Beneath a hot spot, mantle material rises, so the correct convection pattern shows two adjacent cells with upward flow directly under the hot spot and downward flow (sinking) at the far outer edges of the cross section.

Question 38 · 2 pts

Which ocean current would most likely influence the climate of Bouvet Island?

(A) Antarctic Circumpolar Current ✓
(B) Brazil Current
(C) Falkland Current
(D) South Equatorial Current

Worked solution

$\text{Bouvet Island is located in the far southern ocean near Antarctica}$

$\text{The Antarctic Circumpolar Current flows continuously eastward around Antarctica, passing near Bouvet Island's latitude}$

Answer: Antarctic Circumpolar Current

Because Bouvet Island lies in the southern ocean close to Antarctica, it is most directly influenced by the Antarctic Circumpolar Current, which encircles the globe at that latitude, rather than currents found in lower latitudes like the Brazil, Falkland, or South Equatorial Currents.

Question 39 · 2 pts

Base your answers to questions 39 through 41 on the cross section below and on your knowledge of Earth science. The cross section represents a weather front over New York State. A continental polar (cP) air mass is moving into the region now occupied by a maritime tropical (mT) air mass. The arrow shows the direction the cP air mass is moving. Point A is located within the cloud. Which type of frontal boundary is represented?

(A) cold front ✓
(B) warm front
(C) occluded front
(D) stationary front

Worked solution

$\text{Denser cP (cold, dry) air mass is advancing into and undercutting the mT (warm, moist) air mass}$

$\text{A steeply sloped boundary with cold air actively displacing warm air defines a cold front}$

Answer: cold front

The cross section shows the colder, denser continental polar air mass actively advancing and wedging beneath the warmer maritime tropical air mass along a steep boundary, which is characteristic of a cold front.

Question 40 · 2 pts

The relative humidity within the cloud at point A is most likely

(A) 0%
(B) 33%
(C) 50%
(D) 100% ✓

Worked solution

$\text{Clouds form when air is saturated, i.e., water vapor condenses}$

$\text{Saturated air has a relative humidity of 100%}$

Answer: 100%

Since point A is located within a cloud, the air there is saturated with water vapor, meaning its relative humidity is 100%.

Question 41 · 2 pts

Which statement best describes why clouds are forming along the frontal boundary?

(A) The mT air pushes the cP air up, causing it to compress and warm.
(B) The mT air pushes the cP air up, causing it to expand and cool.
(C) The cP air pushes the mT air up, causing it to compress and warm.
(D) The cP air pushes the mT air up, causing it to expand and cool. ✓

Worked solution

$\text{Denser cP air mass undercuts and forces the less-dense mT air mass upward}$

$\text{Rising air enters lower pressure, expands, and cools adiabatically}$

$\text{Cooling to the dew point causes water vapor to condense, forming clouds}$

Answer: The cP air pushes the mT air up, causing it to expand and cool.

The colder, denser continental polar air forces the warmer maritime tropical air upward; as that air rises it moves into lower atmospheric pressure, expands, and cools, eventually condensing to form the cloud along the frontal boundary.

Question 42 · 2 pts

Base your answers to questions 42 through 44 on the diagram below and on your knowledge of Earth science. The diagram represents five maps, labeled A, B, C, D, and E, and the inferred position and shape of the continents on Earth during five periods of geologic time: A = 251 Million Years Ago, B = 200 Million Years Ago, C = 146 Million Years Ago, D = 65.5 Million Years Ago, E = 1.8 Million Years Ago. Between 251 million years ago and 1.8 million years ago, India generally moved

(A) north and east ✓
(B) north and west
(C) south and east
(D) south and west

Worked solution

$\text{On map A (251 mya), India is positioned in the southern hemisphere, attached near Antarctica/Africa}$

$\text{On successive maps (B, C, D, E), India's position shifts progressively toward the equator and then further northeast toward Asia}$

Answer: north and east

Tracking India's position across the five paleogeographic maps shows it drifting away from its southern-hemisphere position near Antarctica, moving generally northward and eastward toward its collision with Asia by 1.8 million years ago.

Question 43 · 2 pts

Pangaea is represented on map

(A) A ✓
(B) E
(C) C
(D) D

Worked solution

$\text{Pangaea was a single supercontinent that existed at the end of the Permian Period, about 251 million years ago}$

$\text{Map A is labeled 251 Million Years Ago and shows all continents joined together}$

Answer: A

Map A, dated 251 million years ago, shows all the continents fused into a single landmass, which corresponds to the supercontinent Pangaea.

Question 44 · 2 pts

Which group of organisms became extinct during the time represented on map A?

(A) placoderm fish
(B) dinosaurs
(C) trilobites ✓
(D) graptolites

Worked solution

$\text{Map A represents 251 million years ago, the end of the Permian Period}$

$\text{The end-Permian mass extinction (251 mya) is when trilobites became completely extinct}$

Answer: trilobites

Map A corresponds to 251 million years ago, the end of the Permian Period, when the end-Permian mass extinction event caused trilobites (which had survived since the early Paleozoic) to go completely extinct.

Question 45 · 2 pts

The rock that formed in the zones of contact metamorphism in the limestone is

(A) quartzite
(B) marble ✓
(C) schist
(D) gneiss

Worked solution

$\text{Parent rock: limestone (composed of calcite)}$

$\text{Contact metamorphism (heat from the diorite sill) recrystallizes calcite}$

$\text{Limestone} \xrightarrow{\text{heat}} \text{marble}$

Answer: marble

Limestone is a sedimentary rock made of calcite; when it undergoes contact metamorphism from heat given off by an intruding igneous body like the Purcell Sill, it recrystallizes into marble.

Question 46 · 2 pts

Which minerals are most likely found together in a sample of diorite taken from Purcell Sill?

(A) quartz, plagioclase feldspar, and pyroxene
(B) plagioclase feldspar, pyroxene, and olivine
(C) plagioclase feldspar, biotite, and amphibole ✓
(D) potassium feldspar, quartz, and biotite

Worked solution

$\text{Diorite is an intermediate-composition intrusive igneous rock}$

$\text{Reference Table Scheme for Igneous Rock Identification: diorite column}$

$\text{Diorite minerals: plagioclase feldspar, amphibole, biotite (little to no quartz)}$

Answer: plagioclase feldspar, biotite, and amphibole

On the Earth Science Reference Tables igneous rock identification chart, diorite is an intermediate rock composed mainly of plagioclase feldspar along with amphibole and biotite, with little or no quartz, pyroxene, or olivine.

Question 47 · 2 pts

The texture of the diorite found in the sill is best described as

(A) fine-grained and non-vesicular
(B) coarse-grained and non-vesicular ✓
(C) fine-grained and vesicular
(D) glassy and vesicular

Worked solution

$\text{Sill = intrusive igneous body, cools slowly underground}$

$\text{Slow cooling allows large mineral crystals to grow} \Rightarrow \text{coarse-grained}$

$\text{No gas escape at depth} \Rightarrow \text{non-vesicular}$

Answer: coarse-grained and non-vesicular

Because the Purcell Sill is an intrusive body that cooled slowly underground, its diorite has large, visible crystals (coarse-grained) and lacks the gas bubble holes (vesicles) seen in rocks that cooled quickly at the surface.

Question 48 · 2 pts

The cross section below represents the shape of the stream channel between x and y at one location along the stream. Which location is best represented by this cross section?

(A) Location A ✓
(B) Location B
(C) Location C
(D) Location D

Worked solution

$\text{A symmetric, evenly-shaped channel cross section occurs where the stream flows relatively straight}$

$\text{At a meander bend, erosion on the outside bank and deposition on the inside bank make the channel asymmetric}$

$\text{Location } A \text{ is on a straighter portion of the stream, so its channel is symmetric}$

Answer: Location A

A symmetric, evenly rounded channel shape (as opposed to a lopsided one with a steep cut bank on one side and a gentle deposit slope on the other) occurs along a relatively straight stretch of the stream, which matches Location A rather than the meander bends at B, C, or D.

Question 49 · 2 pts

The velocity at a certain location in this stream was measured to be 100 centimeters per second. What size sediment particles will be transported at this location?

(A) clay, only
(B) pebbles, only
(C) clay, silt, and some sand, only
(D) clay, silt, sand, and some pebbles, only ✓

Worked solution

$\text{Use the Reference Table: Relationship of Transported Particle Size to Water Velocity}$

$\text{At a stream velocity of } 100 \ \text{cm/s}$

$\text{This velocity is high enough to transport clay, silt, sand, and some pebbles, but not all pebbles/cobbles/boulders}$

Answer: clay, silt, sand, and some pebbles, only

Using the Earth Science Reference Tables graph relating stream velocity to the largest particle size that can be transported, a velocity of 100 cm/s is fast enough to carry clay, silt, and sand, and some (smaller) pebbles, but not the full range of pebbles or larger cobbles/boulders.

Question 50 · 2 pts

What is the name of the depositional feature located at the end of the stream where it enters the ocean?

(A) floodplain
(B) watershed
(C) tributary
(D) delta ✓

Worked solution

$\text{Stream velocity drops sharply where it enters the standing water of the ocean}$

$\text{Sudden loss of velocity} \Rightarrow \text{sediment deposition}$

$\text{This fan-shaped depositional feature at a stream's mouth is a delta}$

Answer: delta

As a stream loses velocity entering the ocean, it deposits its sediment load, building a fan-shaped depositional feature called a delta at its mouth.

Question 51 · 1 pt · constructed response

Identify the nuclear process that produces energy in stars.

Model answer: Nuclear fusion (hydrogen fusing into helium)

Worked solution

$\text{Passage states: hydrogen atoms combine, forming helium, in a nuclear process}$

$\text{Combining of lighter nuclei into a heavier nucleus} = \text{nuclear fusion}$

Answer: Nuclear fusion (hydrogen fusing into helium)

The passage describes hydrogen nuclei combining to form helium, releasing energy; this combining of atomic nuclei is called nuclear fusion.

Question 52 · 1 pt · constructed response

Identify one star that was formerly a Sun-sized star, but is now in its late stage of existence.

Model answer: Sirius B (any accepted white dwarf star listed on the ESRT, such as Sirius B, Procyon B, or 40 Eridani B, is acceptable)

Worked solution

$\text{Passage: a Sun-sized star's late stage of existence is a white dwarf}$

$\text{Consult the Characteristics of Stars chart on the Earth Science Reference Tables}$

$\text{Identify a labeled white dwarf star, e.g., Sirius B}$

Answer: Sirius B (any accepted white dwarf star listed on the ESRT, such as Sirius B, Procyon B, or 40 Eridani B, is acceptable)

According to the passage, a star about the size of the Sun ends its life as a white dwarf; the Reference Tables' Characteristics of Stars chart lists white dwarfs such as Sirius B, Procyon B, and 40 Eridani B as examples.

Question 53 · 1 pt · constructed response

Barnard's Star and Betelgeuse are stars having similar color and surface temperature. Explain why Betelgeuse will most likely undergo a supernova but Barnard's Star will not.

Model answer: Betelgeuse is far more massive than Barnard's Star; only very massive stars end their lives in a supernova explosion, while a low-mass star like Barnard's Star will instead become a red giant and then a white dwarf.

Worked solution

$\text{Same color/temperature but different luminosity/size on the H-R diagram}$

$\text{Betelgeuse is a supergiant (very high mass and luminosity)}$

$\text{Barnard's Star is a small, low-mass main-sequence/red dwarf star}$

$\text{Only stars with much greater mass than the Sun undergo supernova explosions}$

Answer: Betelgeuse is far more massive than Barnard's Star; only very massive stars end their lives in a supernova explosion, while a low-mass star like Barnard's Star will instead become a red giant and then a white dwarf.

Even though the two stars share a similar color and surface temperature, Betelgeuse is a supergiant with vastly more mass, and only very massive stars end their lives explosively as supernovae, whereas the low-mass Barnard's Star will end as a white dwarf without a supernova.

Question 54 · 1 pt · constructed response

Identify the geologic period when Glacial Lake Albany was first formed.

Model answer: Quaternary Period (Pleistocene Epoch)

Worked solution

$\text{Passage: glacier melted, forming the lake, about 15{,}000 years ago}$

$\text{Consult the Geologic History of New York Reference Table (Geologic Time Scale)}$

$15{,}000 \ \text{years ago falls within the Pleistocene Epoch, Quaternary Period}$

Answer: Quaternary Period (Pleistocene Epoch)

An event 15,000 years ago falls within the most recent period on the geologic time scale, the Quaternary Period (Pleistocene Epoch), which includes the end of the last ice age.

Question 55 · 1 pt · constructed response

Identify the entire range of sand sizes covering the lake floor when Glacial Lake Albany drained.

Model answer: 0.006 cm to 0.2 cm (in diameter)

Worked solution

$\text{Consult the Reference Table: particle size scale (silt/sand/pebble boundaries)}$

$\text{Sand ranges from } 0.006 \ \text{cm (boundary with silt) to } 0.2 \ \text{cm (boundary with pebbles)}$

Answer: 0.006 cm to 0.2 cm (in diameter)

On the Earth Science Reference Tables particle-size scale, sand-sized sediment spans from 0.006 cm (the silt/sand boundary) up to 0.2 cm (the sand/pebble boundary).

Question 56 · 1 pt · constructed response

Identify the agent of erosion that formed the sand dunes from the sediments left on the lake floor after Glacial Lake Albany drained.

Model answer: Wind

Worked solution

$\text{Passage: sandy deposits on the exposed lake floor were 'blown into sand dunes'}$

$\text{'Blown' indicates the transporting agent is wind}$

Answer: Wind

The passage states the sandy lake-floor deposits were blown into dunes, indicating wind was the agent of erosion and deposition responsible for forming the dunes.

Question 57 · 1 pt · constructed response

Determine the height of the tide at 5 p.m. on Saturday.

Model answer: Approximately 1.8 to 2.2 meters (read directly off the tide graph at the 5 p.m. Saturday gridline)

Worked solution

$\text{Locate 5 p.m. on the Saturday portion of the x-axis}$

$\text{Trace up to the tide curve, which is rising between the afternoon low (~2 p.m.) and evening high (~8 p.m.)}$

$\text{Read the corresponding height off the y-axis} \approx 1.8\text{-}2.2 \ \text{m}$

Answer: Approximately 1.8 to 2.2 meters (read directly off the tide graph at the 5 p.m. Saturday gridline)

At 5 p.m. Saturday the tide curve is rising steeply from its early-afternoon low toward its evening high, so the height read from the graph at that time is approximately 1.8 to 2.2 meters.

Question 58 · 1 pt · constructed response

Predict the time of the next high tide on Monday. Include a.m. or p.m. in your answer.

Model answer: Approximately 8 a.m. on Monday

Worked solution

$\text{From the graph, high tides occur about every 12 hours, near 8 a.m. and 8 p.m. each day}$

$\text{The last high tide shown (Sunday) occurs near 8 p.m.}$

$\text{Adding one tidal cycle (about 12 hours)} \Rightarrow \text{next high tide} \approx 8 \ \text{a.m. Monday}$

Answer: Approximately 8 a.m. on Monday

Since the graph shows a regular pattern of high tides roughly every 12 hours occurring near 8 a.m. and 8 p.m., continuing that pattern from the Sunday evening high tide predicts the next high tide near 8 a.m. Monday.

Question 59 · 1 pt · constructed response

Identify the force that causes tides.

Model answer: Gravity (the gravitational attraction, mainly of the Moon, and also the Sun, on Earth's oceans)

Worked solution

$\text{Tides result from differential gravitational pull of the Moon (and Sun) on Earth's water}$

Answer: Gravity (the gravitational attraction, mainly of the Moon, and also the Sun, on Earth's oceans)

Tides are caused by the force of gravity, primarily the Moon's gravitational pull on Earth's oceans, with an additional smaller contribution from the Sun.

Question 60 · 1 pt · constructed response

Describe how the thickness of cloud cover at a particular location affects the relative amount of solar radiation reaching Earth's surface.

Model answer: As cloud thickness increases, less solar radiation reaches Earth's surface (thicker clouds reflect more incoming solar radiation back to space).

Worked solution

$\text{Thicker clouds reflect a greater proportion of incoming solar radiation}$

$\text{Less radiation penetrates to reach and be absorbed by Earth's surface}$

$\text{Thin clouds reflect less, allowing more radiation to reach the surface}$

Answer: As cloud thickness increases, less solar radiation reaches Earth's surface (thicker clouds reflect more incoming solar radiation back to space).

The diagram shows thicker clouds reflecting a larger share of incoming solar radiation back to space than thin clouds do, so the thicker the cloud cover, the less solar radiation reaches Earth's surface.

Question 61 · 1 pt · constructed response

State the name of the temperature zone of Earth's atmosphere where most clouds form.

Model answer: Troposphere

Worked solution

$\text{Clouds form in the lowest atmospheric layer, where temperature generally decreases with altitude}$

$\text{This layer is the troposphere}$

Answer: Troposphere

Nearly all clouds and weather occur in the troposphere, the lowest layer of Earth's atmosphere, where temperature decreases with increasing height.

Question 62 · 1 pt · constructed response

On the diagram in your answer booklet, shade the portion of Earth that represents nighttime.

Model answer: Shade the half of Earth's globe that is on the side facing away from the incoming sunlight rays shown in the diagram, i.e., the hemisphere not illuminated by the Sun.

Worked solution

$\text{Identify the direction from which the Sun's rays strike Earth in the diagram}$

$\text{The illuminated half (facing the Sun) is daytime}$

$\text{The unilluminated half (facing away from the Sun) is nighttime; shade that half}$

Answer: Shade the half of Earth's globe that is on the side facing away from the incoming sunlight rays shown in the diagram, i.e., the hemisphere not illuminated by the Sun.

On any diagram of Earth viewed from space with parallel sunlight rays drawn, the correct shading task is to shade the hemisphere on the side of Earth facing away from the Sun, since that half is in darkness (nighttime) while the sunlit half is daytime.

Question 63 · 1 pt · constructed response

Identify the season that is beginning in the northern hemisphere when Earth is in this position.

Model answer: Summer. In the diagram the North Pole is tilted toward the Sun, so the Sun's vertical rays strike the Tropic of Cancer (23.5 degrees north). This is the June solstice, the day summer begins in the Northern Hemisphere.

Worked solution

$\text{The North Pole is tilted toward the Sun, so the Northern Hemisphere is most directly lit.}$

$\text{The Sun\'s vertical rays strike the Tropic of Cancer, } 23.5\degree\text{ N.}$

$\text{This is the June solstice (about June 21), when summer begins in the Northern Hemisphere.}$

Answer: Summer. In the diagram the North Pole is tilted toward the Sun, so the Sun's vertical rays strike the Tropic of Cancer (23.5 degrees north). This is the June solstice, the day summer begins in the Northern Hemisphere.

The North Pole is tilted toward the Sun, placing the Sun's direct rays on the Tropic of Cancer. That is the June solstice, so the season beginning in the Northern Hemisphere is summer.

Question 64 · 1 pt · constructed response

State the number of daylight hours that an observer at the equator would experience on this day.

Model answer: 12 hours

Worked solution

$\text{The equator is always bisected equally by the circle of illumination}$

$\text{Regardless of Earth's axial tilt or season, the equator receives } 12 \ \text{hours of daylight and } 12 \ \text{hours of darkness}$

Answer: 12 hours

Because the circle of illumination always divides the equator exactly in half, an observer at the equator experiences 12 hours of daylight on any day of the year, including the day shown in this diagram.

Question 65 · 1 pt · constructed response

Compared to current summer and winter temperatures in New York State, describe how New York State's summer and winter temperatures would change if Earth's rotational axis were tilted at 33.5 degrees instead of 23.5 degrees.

Model answer: Summers in New York State would become warmer (hotter) and winters would become colder, i.e., the seasonal temperature contrast would increase.

Worked solution

$\text{Greater axial tilt} \Rightarrow \text{greater seasonal variation in the Sun's altitude/insolation angle at NY's latitude}$

$\text{In summer, the Sun would appear even higher in the sky, delivering more direct, intense insolation} \Rightarrow \text{warmer summers}$

$\text{In winter, the Sun would appear even lower in the sky, delivering more indirect, spread-out insolation} \Rightarrow \text{colder winters}$

Answer: Summers in New York State would become warmer (hotter) and winters would become colder, i.e., the seasonal temperature contrast would increase.

Increasing Earth's axial tilt from 23.5 degrees to 33.5 degrees would increase the range of the Sun's noon altitude throughout the year at New York's latitude, making summer insolation more direct and intense (warmer summers) and winter insolation more indirect (colder winters), so the difference between summer and winter temperatures would grow larger.

Question 66 · 1 pt · constructed response

Identify the process that recrystallizes silica-rich rock and limestone into wollastonite using heat and pressure.

Model answer: Metamorphism (contact/regional metamorphism)

Worked solution

$\text{Passage: wollastonite forms when silica-rich rock and limestone are deeply buried and recrystallized at } 400^{\circ}\text{C to } 450^{\circ}\text{C}$

$\text{Recrystallization of existing rock under heat and pressure without melting} = \text{metamorphism}$

Answer: Metamorphism (contact/regional metamorphism)

The recrystallization of pre-existing rock under elevated heat and pressure, without melting, that forms a new mineral like wollastonite is the process of metamorphism.

Question 67 · 1 pt · constructed response

Base your answers to questions 66 through 68 on the passage and map below and on your knowledge of Earth science. The map shows a portion of northeastern New York State and northwestern Vermont. Wollastonite, A Versatile Industrial Mineral Wollastonite is a mineral composed of calcium, silicon, and oxygen (CaSiO3). The formation of wollastonite can occur when a large area of silica-rich rock and limestone is deeply buried and recrystallized at temperatures from 400°C to 450°C. The Lewis Deposit, located in Willsboro, New York, contains approximately 60% wollastonite. Since the early 1980s wollastonite has been used as a replacement for asbestos in products such as insulating boards and panels, roofing tiles, and brakes. Wollastonite is also used in ceramic glaze mixes. 67 Identify one mineral, other than wollastonite, that is used in ceramics.

Model answer: Feldspar (also accept quartz or kaolinite/clay)

Worked solution

$\text{Feldspar, quartz, and clay minerals (e.g., kaolinite) are common raw materials in ceramic bodies and glazes}$

Answer: Feldspar (also accept quartz or kaolinite/clay)

Any mineral commonly used as a raw material in ceramics other than wollastonite is acceptable, such as feldspar, quartz, or kaolinite (clay).

Question 68 · 1 pt · constructed response

Base your answers to questions 66 through 68 on the passage and map below and on your knowledge of Earth science. The map shows a portion of northeastern New York State and northwestern Vermont. Wollastonite, A Versatile Industrial Mineral Wollastonite is a mineral composed of calcium, silicon, and oxygen (CaSiO3). The formation of wollastonite can occur when a large area of silica-rich rock and limestone is deeply buried and recrystallized at temperatures from 400°C to 450°C. The Lewis Deposit, located in Willsboro, New York, contains approximately 60% wollastonite. Since the early 1980s wollastonite has been used as a replacement for asbestos in products such as insulating boards and panels, roofing tiles, and brakes. Wollastonite is also used in ceramic glaze mixes. Identify the New York State landscape region in which Plattsburgh, New York, is located.

Model answer: Champlain Lowlands

Worked solution

$\text{Plattsburgh lies on the western shore of Lake Champlain}$

$\text{On the NYS Landscape Regions map (ESRT), this lowland strip along the lake is the Champlain Lowlands}$

Answer: Champlain Lowlands

Plattsburgh sits in the low-lying land bordering Lake Champlain, which is designated the Champlain Lowlands on the New York State Landscape Regions map.

Question 69 · 1 pt · constructed response

Base your answers to questions 69 and 70 on the diagram and table below and on your knowledge of Earth science. The diagram represents the laboratory materials used for investigations of how bead diameter affects infiltration, porosity, and water retention. Each column was filled to the same level with uniform-sized, dry, spherical beads. Water was added to fill each column to the top of the beads. The clamps were then opened to allow the water to drain into the beakers beneath each column. The time it took the water to drain and the amount of water left in each column was calculated. The table shows the results of the investigation. Effects of Bead Diameter | Bead Diameter (mm) | Infiltration Rate (mm/s) | Porosity (%) | Retention (mL) | | --- | --- | --- | --- | | 0.4 | 18 | 40 | 22 | | 1.0 | 25 | 40 | 16 | | 2.1 | 31 | 40 | 11 | | 3.5 | 34 | 40 | 9 | | 5.0 | 36 | 40 | 5 | 69 On the grid in your answer booklet, construct a line graph by plotting the infiltration rates for the five bead diameters listed in the table. Connect the five plots with a line.

Model answer: A line graph with Bead Diameter (mm) on the x-axis and Infiltration Rate (mm/s) on the y-axis, plotting the points (0.4, 18), (1.0, 25), (2.1, 31), (3.5, 34), and (5.0, 36), connected in order from left to right with a single line.

Worked solution

$(0.4,\ 18),\ (1.0,\ 25),\ (2.1,\ 31),\ (3.5,\ 34),\ (5.0,\ 36)$

$\text{Plot each point and connect them in sequence with straight line segments}$

Answer: A line graph with Bead Diameter (mm) on the x-axis and Infiltration Rate (mm/s) on the y-axis, plotting the points (0.4, 18), (1.0, 25), (2.1, 31), (3.5, 34), and (5.0, 36), connected in order from left to right with a single line.

Plotting infiltration rate against bead diameter and connecting the five points shows infiltration rate rising as bead size increases.

Question 70 · 1 pt · constructed response

Base your answers to questions 69 and 70 on the diagram and table below and on your knowledge of Earth science. The diagram represents the laboratory materials used for investigations of how bead diameter affects infiltration, porosity, and water retention. Each column was filled to the same level with uniform-sized, dry, spherical beads. Water was added to fill each column to the top of the beads. The clamps were then opened to allow the water to drain into the beakers beneath each column. The time it took the water to drain and the amount of water left in each column was calculated. The table shows the results of the investigation. Effects of Bead Diameter | Bead Diameter (mm) | Infiltration Rate (mm/s) | Porosity (%) | Retention (mL) | | --- | --- | --- | --- | | 0.4 | 18 | 40 | 22 | | 1.0 | 25 | 40 | 16 | | 2.1 | 31 | 40 | 11 | | 3.5 | 34 | 40 | 9 | | 5.0 | 36 | 40 | 5 | 70 State the relationship between increasing bead size and the amount of water retention in the column.

Model answer: As bead diameter increases, water retention decreases (an inverse relationship).

Worked solution

$0.4\text{ mm} \rightarrow 22\text{ mL}$

$5.0\text{ mm} \rightarrow 5\text{ mL}$

$\text{Retention decreases steadily as diameter increases}$

Answer: As bead diameter increases, water retention decreases (an inverse relationship).

The table shows retention falling from 22 mL to 5 mL as bead diameter rises from 0.4 mm to 5.0 mm, so the relationship is inverse: bigger beads hold less water.

Question 71 · 1 pt · constructed response

Base your answers to questions 71 and 72 on the bathymetric map below and on your knowledge of Earth science. The map shows the depth of White Lake located in Sullivan County, New York. Isoline values indicate water depth in feet. The surface of White Lake is 1323 feet above sea level. Points A and B represent locations on the shoreline of White Lake. Point C represents a location on the bottom of the lake. On the grid in your answer booklet, construct a profile of the depth of White Lake from point A to point B. Plot each point where an isoline showing depth is crossed by line AB. Points A and B have been plotted on the graph. Connect the plots with a line, starting at A and ending at B, to complete the profile.

Model answer: A depth profile starting at 0 ft at point A, descending as the line crosses the 20 ft, 40 ft, and 60 ft isolines to a maximum depth near the middle of line AB, then rising back up through those same isolines to 0 ft at point B, all points connected with straight line segments in the order they are crossed.

Worked solution

$\text{Depth} = 0 \text{ ft at A and B (shoreline)}$

$\text{Depth increases to a maximum where line AB crosses the innermost isoline it intersects}$

$\text{Connect all plotted points from A to B with a single line}$

Answer: A depth profile starting at 0 ft at point A, descending as the line crosses the 20 ft, 40 ft, and 60 ft isolines to a maximum depth near the middle of line AB, then rising back up through those same isolines to 0 ft at point B, all points connected with straight line segments in the order they are crossed.

A topographic/bathymetric profile is built by plotting the elevation (here, depth) at every point where the traverse line crosses a contour, then connecting those points in order.

Question 72 · 1 pt · constructed response

Model answer: Any value greater than 80 feet and less than 100 feet is acceptable (e.g., 85 feet).

Worked solution

$\text{Point C is inside the closed 80 ft contour}$

$\text{No deeper contour line is drawn, so the depth interval rule gives } 80 < depth < 100 \text{ ft}$

Answer: Any value greater than 80 feet and less than 100 feet is acceptable (e.g., 85 feet).

Because point C lies within the innermost (80 ft) closed contour and no higher contour is shown, its true depth must be greater than 80 ft but less than the next contour interval of 100 ft, so any value in that range, such as 85 feet, is acceptable.

Question 73 · 1 pt · constructed response

Base your answers to questions 73 through 75 on the data table below and on your knowledge of Earth science. The data table lists the distance from Earth to the Moon and the percentage of the lighted portion of the Moon visible from Earth each day for a 9-day period. | Day | Approximate Earth-Moon Distance (km) | Lighted portion of Moon Visible (%) | | --- | --- | --- | | 1 | 393,300 | 84 | | 2 | 397,600 | 76 | | 3 | 400,900 | 67 | | 4 | 403,200 | 58 | | 5 | 404,300 | 49 | | 6 | 404,000 | 39 | | 7 | 402,500 | 30 | | 8 | 399,800 | 22 | | 9 | 396,300 | 14 | 73 On the diagram in your answer booklet, place an X on the Moon's orbit to show the approximate position of the Moon on day 5.

The answer booklet diagram shows the Moon's slightly elliptical orbit around Earth, with Earth positioned off-center so that one side of the orbit is closest to Earth (perigee) and the opposite side is farthest from Earth (apogee). Use the data table: on day 5 the Earth-Moon distance (404,300 km) is the greatest value listed, so the X belongs at the point on the orbit farthest from Earth.

Model answer: An X placed on the point of the Moon's orbit that is farthest from Earth (apogee), because day 5 shows the maximum Earth-Moon distance in the table (404,300 km), with the Moon's lighted side (49% illuminated) facing appropriately toward the Sun's direction shown on the diagram.

Worked solution

$\text{Day 5 distance} = 404{,}300\text{ km (the maximum value in the table)}$

$\text{Maximum Earth-Moon distance corresponds to apogee, the farthest point on the elliptical orbit}$

Answer: An X placed on the point of the Moon's orbit that is farthest from Earth (apogee), because day 5 shows the maximum Earth-Moon distance in the table (404,300 km), with the Moon's lighted side (49% illuminated) facing appropriately toward the Sun's direction shown on the diagram.

Since day 5 has the largest Earth-Moon distance listed, the Moon on that day is at apogee, the point on its elliptical orbit farthest from Earth.

Question 74 · 1 pt · constructed response

Base your answers to questions 73 through 75 on the data table below and on your knowledge of Earth science. The data table lists the distance from Earth to the Moon and the percentage of the lighted portion of the Moon visible from Earth each day for a 9-day period. | Day | Approximate Earth-Moon Distance (km) | Lighted portion of Moon Visible (%) | | --- | --- | --- | | 1 | 393,300 | 84 | | 2 | 397,600 | 76 | | 3 | 400,900 | 67 | | 4 | 403,200 | 58 | | 5 | 404,300 | 49 | | 6 | 404,000 | 39 | | 7 | 402,500 | 30 | | 8 | 399,800 | 22 | | 9 | 396,300 | 14 | 74 State the number of days (d) it takes the Moon to complete one cycle of phases from one full moon to the next full moon.

Model answer: 29.5 days

Worked solution

$\text{The synodic month (full moon to full moon) lasts approximately } 29.5\text{ d}$

Answer: 29.5 days

The time from one full moon to the next full moon is the synodic month, which is about 29.5 days.

Question 75 · 1 pt · constructed response

Base your answers to questions 73 through 75 on the data table below and on your knowledge of Earth science. The data table lists the distance from Earth to the Moon and the percentage of the lighted portion of the Moon visible from Earth each day for a 9-day period. | Day | Approximate Earth-Moon Distance (km) | Lighted portion of Moon Visible (%) | | --- | --- | --- | | 1 | 393,300 | 84 | | 2 | 397,600 | 76 | | 3 | 400,900 | 67 | | 4 | 403,200 | 58 | | 5 | 404,300 | 49 | | 6 | 404,000 | 39 | | 7 | 402,500 | 30 | | 8 | 399,800 | 22 | | 9 | 396,300 | 14 | 75 Explain how the data provide evidence that the Moon has an elliptical orbit around Earth.

Model answer: The Earth-Moon distance in the table changes over the 9 days (ranging from about 393,300 km up to 404,300 km) instead of staying constant, which shows the Moon's orbit is not a perfect circle centered on Earth; a changing distance is evidence of an elliptical orbit, with Earth located off-center at one focus.

Worked solution

$\text{Minimum distance} = 393{,}300\text{ km (day 1)}$

$\text{Maximum distance} = 404{,}300\text{ km (day 5)}$

$\text{A circular orbit centered on Earth would give a constant distance; the varying distance indicates an ellipse}$

Answer: The Earth-Moon distance in the table changes over the 9 days (ranging from about 393,300 km up to 404,300 km) instead of staying constant, which shows the Moon's orbit is not a perfect circle centered on Earth; a changing distance is evidence of an elliptical orbit, with Earth located off-center at one focus.

Because the recorded Earth-Moon distance rises and falls rather than staying fixed, the Moon's path around Earth cannot be a circle centered on Earth; the changing distance is the signature of an elliptical orbit.

Question 76 · 1 pt · constructed response

Base your answers to questions 76 through 79 on the Surface Air Temperature map in your answer booklet, the two Extreme Storms and Winds maps below, and on your knowledge of Earth science. The Surface Air Temperature map shows the surface air temperatures, recorded in degrees Fahrenheit (°F), across the United States at 6 p.m. on October 25, 2010. The 40°F isotherm is drawn. The shaded portions on the two Extreme Storms and Winds maps show the areas where extreme storms and winds (including tornadoes) were forecasted on October 25, 2010 and October 26, 2010. Letters W, X, Y, and Z represent the same surface locations on all maps. On the map in your answer booklet, draw the 70°F isotherm. Extend the line to the edges of the United States.

Model answer: A smooth line connecting all points on the Surface Air Temperature map where the temperature reads 70°F, drawn so that it does not cross itself and is extended until it reaches both edges of the map (or closes into a loop if it does not reach an edge).

Worked solution

$\text{Locate all plotted station temperatures equal to, or interpolate between stations that bracket, } 70^{\circ}F$

$\text{Connect these points with a single smooth, non-crossing line and extend it to the map edges}$

Answer: A smooth line connecting all points on the Surface Air Temperature map where the temperature reads 70°F, drawn so that it does not cross itself and is extended until it reaches both edges of the map (or closes into a loop if it does not reach an edge).

An isotherm is drawn by connecting points of equal temperature; the 70°F line is traced by interpolating between the plotted station values and extended to the boundary of the map.

Question 77 · 1 pt · constructed response

Base your answers to questions 76 through 79 on the Surface Air Temperature map in your answer booklet, the two Extreme Storms and Winds maps below, and on your knowledge of Earth science. 77 The lowest temperatures on the Surface Air Temperature map are inside the 40°F isotherm. This region is part of the Rocky Mountains. Identify the climate factor that accounts for the low surface air temperatures in this mountain region.

Model answer: Elevation (altitude)

Worked solution

$\text{Air temperature decreases with increasing elevation (average lapse rate} \approx 3.6^{\circ}F\text{ per 1000 ft)}$

Answer: Elevation (altitude)

The Rocky Mountains reach high elevations, and temperature drops as elevation increases, which explains the unusually cool readings there compared to surrounding lower-elevation areas.

Question 78 · 1 pt · constructed response

Base your answers to questions 76 through 79 on the Surface Air Temperature map in your answer booklet, the two Extreme Storms and Winds maps below, and on your knowledge of Earth science. Identify the evidence on the October 25 Extreme Storms and Winds map that indicates location Z has a dewpoint that is close to the air temperature.

Model answer: Location Z lies within the shaded region forecast for extreme storms/tornadoes on October 25, which shows that clouds and precipitation are forming there; clouds and precipitation only form when the air is saturated, which happens when the dewpoint is close to (equal to) the air temperature.

Worked solution

$\text{Z is inside the shaded severe-storm/tornado zone}$

$\text{Storms require saturated air (relative humidity} \approx 100\%)$

$\text{Saturation occurs when dewpoint} \approx \text{air temperature}$

Answer: Location Z lies within the shaded region forecast for extreme storms/tornadoes on October 25, which shows that clouds and precipitation are forming there; clouds and precipitation only form when the air is saturated, which happens when the dewpoint is close to (equal to) the air temperature.

Because location Z falls within the area forecast for severe storms and tornadoes, the air there must be saturated enough to produce clouds and precipitation, which only occurs when the dewpoint is nearly equal to the air temperature.

Question 79 · 1 pt · constructed response

Base your answers to questions 76 through 79 on the Surface Air Temperature map in your answer booklet, the two Extreme Storms and Winds maps below, and on your knowledge of Earth science. 79 Other than stocking up on food and water, describe two emergency actions that should be taken in order to prevent loss of life and property in the regions where damaging storms and possible tornadoes were forecast on October 25 and 26.

Model answer: (1) Take shelter immediately in a basement or an interior room on the lowest floor, away from windows; (2) Evacuate mobile homes and outdoor/temporary structures and move people and vehicles to a sturdy, permanent building.

Worked solution

$\text{Action 1: seek shelter in a basement or interior room away from windows}$

$\text{Action 2: evacuate mobile homes/vulnerable structures to a sturdy building}$

Answer: (1) Take shelter immediately in a basement or an interior room on the lowest floor, away from windows; (2) Evacuate mobile homes and outdoor/temporary structures and move people and vehicles to a sturdy, permanent building.

Standard severe weather safety practice calls for taking shelter in the safest interior part of a sturdy building and evacuating people from mobile homes or flimsy structures that tornadoes and high winds can destroy.

Question 80 · 1 pt · constructed response

Base your answers to questions 80 through 82 on the cross section below and on your knowledge of Earth science. Letters A through J represent different rock units. Letter X represents a fault line, and letter Y represents an unconformity. The rock units have not been overturned. 80 Describe one piece of evidence shown in the diagram that leads to the inference that crustal movement occurred in this region.

Model answer: The presence of fault X, which shows the rock layers displaced (offset) on either side of it, is evidence that crustal movement (faulting) occurred in this region.

Worked solution

$\text{Fault X cuts across rock layers, offsetting them from their original continuous positions}$

$\text{Offset layers across a fracture indicate movement of the crust}$

Answer: The presence of fault X, which shows the rock layers displaced (offset) on either side of it, is evidence that crustal movement (faulting) occurred in this region.

Displacement of rock layers across fault X, or alternatively the tilting of the lower rock units, both indicate that the crust in this region has moved after the rocks formed.

Question 81 · 1 pt · constructed response

Base your answers to questions 80 through 82 on the cross section below and on your knowledge of Earth science. Letters A through J represent different rock units. Letter X represents a fault line, and letter Y represents an unconformity. The rock units have not been overturned. 81 Place the letters of the following rock units and the fault in order from oldest to youngest. C D E Fault X

Model answer: C, D, E, Fault X (oldest to youngest)

Worked solution

$\text{C is the host rock intruded by D} \Rightarrow C \text{ is older than } D$

$\text{E cuts across both C and D} \Rightarrow E \text{ is younger than both}$

$\text{Fault X offsets E} \Rightarrow \text{Fault X is the youngest event}$

Answer: C, D, E, Fault X (oldest to youngest)

Using the principle of cross-cutting relationships, an intrusion or fault is always younger than the rock it cuts through: D intrudes C, E cuts across C and D, and fault X displaces E, giving the order C, D, E, then Fault X.

Question 82 · 1 pt · constructed response

Base your answers to questions 80 through 82 on the cross section below and on your knowledge of Earth science. Letters A through J represent different rock units. Letter X represents a fault line, and letter Y represents an unconformity. The rock units have not been overturned. 82 Rock unit G formed during the late Cambrian period, and Rock unit J formed during the early Ordovician period. Identify the name of one New York State index fossil that could possibly be found in Rock unit H.

Model answer: Trilobite

Worked solution

$\text{H lies stratigraphically between G (late Cambrian) and J (early Ordovician)}$

$\text{So H formed at the very end of the Cambrian or very start of the Ordovician}$

$\text{Trilobites are index fossils found in New York rocks spanning the Cambrian-Ordovician boundary}$

Answer: Trilobite

Because rock unit H sits between a late Cambrian unit and an early Ordovician unit, it formed near the Cambrian-Ordovician boundary; trilobites are New York State index fossils known from rock of that age.

Question 83 · 1 pt · constructed response

Base your answers to questions 83 through 85 on the data table and map below and on your knowledge of Earth science. The data table shows the location, diameter, and age of some impact craters on Earth. The latitude and longitude of the Sierra Madera, Texas, crater has been left blank. The location of the Sierra Madera crater is indicated on the map of Texas. | Crater | Latitude | Longitude | Diameter (km) | Age (yrs.) | | --- | --- | --- | --- | --- | | Meteor Crater | 35°N | 111°W | 1.2 | 50,000 | | Chicxulub | 23°N | 90°W | 180 | 65.5 million | | Sierra Madera | | | 13 | 100 million | | Red Wing Creek | 48°N | 104°W | 9 | 200 million | | Wells Creek | 36°N | 88°W | 14 | 200 million | | Clearwater Lakes | 56°N | 74°W | 22 | 290 million | | Pilot Lake | 60°N | 111°W | 6 | 440 million | 83 Determine the latitude and longitude, to the nearest whole degree, of the Sierra Madera crater. Include units and compass directions in your answer.

Model answer: Approximately 30°N, 102°W

Worked solution

$\text{Reading the gridlines nearest the plotted dot: latitude} \approx 30^{\circ}N$

$\text{longitude} \approx 102^{\circ}W$

Answer: Approximately 30°N, 102°W

The dot marking Sierra Madera on the Texas map falls closest to the 30°N latitude line and the 102°W longitude line.

Question 84 · 1 pt · constructed response

Base your answers to questions 83 through 85 on the data table and map below and on your knowledge of Earth science. The data table shows the location, diameter, and age of some impact craters on Earth. | Crater | Diameter (km) | | --- | --- | | Meteor Crater | 1.2 | | Chicxulub | 180 | | Sierra Madera | 13 | | Red Wing Creek | 9 | | Wells Creek | 14 | | Clearwater Lakes | 22 | | Pilot Lake | 6 | 84 State the name of the crater that has a diameter approximately equal to the straight line distance, in kilometers, between Ithaca, New York and Slide Mountain, New York.

From the Generalized Landscape Regions of New York State map in the Earth Science Reference Tables: | Location | Position on ESRT NY map | | --- | --- | | Ithaca | south-central NY, at the southern end of Cayuga Lake (about 42.4 N, 76.5 W) | | Slide Mountain | in the Catskills of southeastern NY (about 42.0 N, 74.4 W) | Measured with the map scale, the straight line distance between Ithaca and Slide Mountain is approximately 180 km.

Model answer: Chicxulub

Worked solution

$\text{Ithaca, NY} \approx 42.4^{\circ}N, 76.5^{\circ}W;\quad \text{Slide Mountain, NY} \approx 42.0^{\circ}N, 74.4^{\circ}W$

$\Delta\text{lat} \approx 0.4^{\circ}\ (\approx 45\text{ km}),\quad \Delta\text{long} \approx 2.1^{\circ}\ (\approx 170\text{ km at this latitude})$

$\text{distance} = \sqrt{45^2+170^2} \approx 176\text{ km}$

$\text{This is closest to the Chicxulub crater's diameter of 180 km}$

Answer: Chicxulub

Using the ESRT map of New York State, the straight-line distance from Ithaca to Slide Mountain is roughly 175 to 180 km, which matches the 180 km diameter of the Chicxulub crater in the table.

Question 85 · 1 pt · constructed response

Base your answers to questions 83 through 85 on the data table and map below and on your knowledge of Earth science. 85 Identify one type of solar system object that could have impacted Earth's surface to create any of these craters.

Model answer: An asteroid (accept also: meteoroid or comet)

Worked solution

$\text{Impact craters on Earth are formed by collisions with solar system objects such as asteroids, meteoroids, or comets}$

Answer: An asteroid (accept also: meteoroid or comet)

Impact craters like those in the table are created when objects such as asteroids (or meteoroids/comets) strike Earth's surface at high speed.

January 2025 Earth Science Regents — Answer Key & Worked Solutions

More Earth Science Regents help