Science 10 Periodical Test

What makes up the lithosphere?

• Variety of solid rocks like sedimentary, metamorphic, and igneous

• Continental crust where a relatively young mountain is present

• Rocks that have an average density of 8.2 g/cm3

• Several segments called plates

A plate-tectonic researcher collects data from two adjoining plates: Plate 1: crustal thickness ≈ 8 km, density ≈ 3.0 g/cm³, basaltic composition Plate 2: crustal thickness ≈ 35 km, density ≈ 2.7 g/cm³, granitic composition When these two plates converge, which sequence best describes the ensuing geologic processes?

• Plate 1 overrides Plate 2, generating a broad plateau on the older plate.

• Plate 2 subducts beneath Plate 1, producing an island-arc chain and back-arc basin.

• Both plates crumple equally, uplifting a symmetric mountain range without volcanism.

• Plate 1 subducts beneath Plate 2, forming a deep-ocean trench and a continental volcanic arc.

What feature of Earth's lithosphere provides evidence that it is divided into plates? It is _______________________

• continuous, unbroken shell.

• composed of rigid sections that move independently.

• flexible layer that bends and stretches without breaking.

• made of a single layer of rock covering the entire Earth.

A geologist is tasked with identifying the major lithospheric plates on a world map. Which observation would help them correctly infer the boundaries of these plates?

• Ocean currents align with the edges of tectonic plates.

• Mountain ranges are evenly distributed across all continents.

• Weather patterns are consistent along tectonic plate boundaries.

• Earthquake epicenters and volcanic activity are concentrated along specific zones.

A tectonic map shows the Pacific Plate surrounded by trenches, ridges, and transform faults. What does this suggest about the Pacific Plate? It is __________________________ .

• stationary and does not interact with other plates.

• the largest lithospheric plate and interacts with multiple boundaries.

• smaller than most plates and only interacts with one or two boundaries.

• entirely surrounded by divergent boundaries, creating new crust on all sides.

Which observation best supports the inference that Earth's lithosphere is divided into rigid plates?

• Earthquakes follow narrow, linear belts.

• Continents fit like puzzle pieces and have matching coastlines.

• Zones of frequent earthquakes encircle ocean basins and align with deep-sea trenches.

• Earthquakes occur along the edges of large, rigid lithospheric plates that move relative to each other.

Why do primary waves arrive before secondary and surface waves during an earthquake? They are________________ .

• slower but take a shorter path.

• the only waves that move vertically through the crust.

• travelling through both solids and liquids at high speed.

• generated later but move faster than other seismic waves.

A seismologist observes that S-waves are absent in certain regions of the Earth. Where are these regions located? In the Earth's ________________ .

• liquid outer core.

• solid inner core.

• crust near tectonic plate boundaries.

• mantle near subduction zones.

Where is the earthquake epicenter located when using the triangulation method? At the _____________________ .

• location with the highest magnitude reading

• midpoint between the three seismic stations

• point where the three circles intersect

• station closest to the earthquake origin

Why are three seismic stations required for triangulation instead of just two? To ____________________ .

• increases precision in locating the earthquake's epicenter.

• create multiple circles that converge and help pinpoint the epicenter more accurately.

• obtain a single intersection point from three circles, each representing the distance from a station to the epicenter.

• avoid ambiguity that may arise when only two stations are used, which can result in multiple possible epicenter locations.