Correct Answer: Option 1 – Edges of tectonic plates

Correct Answer: Option 4 – More dense and more Mafic

The crust covers the mantle and is the earth's hard outer shell, the surface on which we are living. Compared to the other layers the crust is much thinner. It floats upon the softer, denser mantle. The crust is made up of solid material but this material is not the same everywhere. There is an Oceanic crust and a Continental crust.

The Oceanic crust is about 4-7 miles (6-11 km) thick and mainly consists of heavy rocks, like basalt. The Continental crust is thicker than the Oceanic crust, about 19 miles (30 km) thick. It is mainly made up of light material like granite.

Correct Answer: Option 1 – Silicon

40 minerals represent more than 99% of the mass of Earth's crust. In terms of percentage of Earth's crust by weight, oxygen and silicon account for nearly 75% of Earth's crust. Oxygen is the most abundant element (approximately 46.6% followed by silicon, approximately 27.7%). In order of percentage by weight, other important elements include aluminum, iron, calcium, sodium, potassium, and magnesium. All other elements (e.g., gold, silver, copper, etc.) compose the remaining one to two percent of the crust.

Correct Answer: Option 4 – Dolostone

Dolostone or dolomite rock (composed of calcium magnesium carbonate CaMg(CO₃)₂) is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite.

Hence the other 3 options are incorrect

Correct Answer: Option 4 – volcanic with rapid cooling

Rate of Cooling – a primary control on texture, determines the relative rate of crystal nucleation and growth

1. slow cooling – few large crystals produced by growth rate greater than nucleation rate
2. rapid cooling – many small crystals produced by nucleation rate greater than growth rate

Correct Answer: Option 4 – Hudson highlands and Adirondack Mountains

The geographical map providing information on the nomenclature of the places has been overlapped with the areas where buried and exposed Grenville rocks are present. Hence, it is evident from the map above that, Hudson highlands and Adirondack Mountains have exposed Grenville-age bedrock.

Correct Answer: Option 4 – Erosion of the igneous rock exposed at the surface

Since the sediment layers are formed due to continual deposition process, an event such as erosion that occurred most recently leads to formation of rock exposed at the surface. The diagram above shows the exposed part of igneous rock undergoing erosion. Hence, option 4 is the correct answer.

Layer A is in the lower part of the section. Hence, it is an older layer and option 1 is incorrect.

Formation of layer D falls next only to the erosion of the exposed igneous rock layer. Hence, it is not the most recent event and option 2 is incorrect.

Correct Answer: Option 1 – Granite

Granite, which makes up 70–80% of Earth's crust, is an igneous rock formed of interlocking crystals of quartz, feldspar, mica, and other minerals in lesser quantities. Large masses of granite are a major ingredient of mountain ranges. Granite is a plutonic rock, meaning that it forms deep underground. Slow cooling gives atoms time to migrate to the surfaces of growing crystals, resulting in a coarse or mottled crystalline structure easily visible to the naked eye.

Correct Answer: Option 4 – Compaction and cementation

Correct Answer:

P-waves - also called primary or compressional waves have the following properties:

• They travel the fastest.
• They travel in the same direction as the particles they vibrate (see diagram 1).
• They travel through solids, liquids and gases.
• They travel faster through denser materials (density increases with depth on the earth).

S-waves- also called secondary or shear waves have the following properties:

• S waves do not pass through outer layer
• They travel slower than P-waves.
• They travel to right angles to the vibration of the particles
• S-waves cannot pass through liquids or gases.
• They travel faster through denser materials.

In the section above the earthquake epicenter and seismic station A are located on the outer layer – Mantle of the Earth. Hence, only P-waves reach the station A and not S waves.