GEOL 1110 Lab Midterm

Biotite

Muscovite

Pyrite

Calcite

Hematite

Halite

Magnetite

Talc

Plagioclase Feldspar

Potassium Feldspar

Galena

Olivine

Quartz

Gabbro

Granite

Pegmatite Granite

Pumice

Scoria/Vesicular Basalt

Basalt

Diorite

Volcanic Breccia/Tuff

Porphyritic Rhyolite

Porphyritic Andesite

Obsidian

Is plate tectonics a theory or a hypothesis? Why?

A theory, because it has been tested multiple times and is globally accepted.

What are the three compositional layers of the Earth?

Core; Mantle; Crust

What crust type is thicker: continental or oceanic?

Continental

Which crust type is denser: continental or oceanic?

Oceanic

What are the five types of mechanical layers of the Earth?

Inner Core; Outer Core; Lower Mantle: Asthenosphere: Lithosphere

The rigid outermost layer of the Earth that is broken into tectonic plates is called the lithosphere. What is the lithosphere composed of?

The crust and the upper mantle

The lithosphere plates rest on a solid, low-rigidity zone in the upper mantle called the _____.

Asthenosphere

What are the three types of plate boundaries?

Divergent, Convergent and Transform

At which plate boundary is lithosphere created?

Divergent

At which plate boundary is lithosphere destroyed?

Convergent

What is created when an intense jet of heat melts part of the upper mantle? What commonly forms above this location?

Hotspot; Volcano

What are the five physical properties of minerals that allow them to be identified?

Color, Streak, Luster, Breakage, and Hardness

Color

The visible color of a mineral to the naked eye

Streak

The color of the power left behind a mineral

Luster

The way light reflects/interacts with a mineral’s surface

Breakage

The way a mineral breaks along weak atoms

Hardness

Measure how easily it can scratch or be scratched by another surface

What are the two types of breakage?

Cleavage and Fracture

What are the two types of fracture?

Conchoidal and Irregular

What is the difference between a rock and a mineral?

A rock is composed of minerals. A mineral is a naturally occurring solid that has a definable chemical composition.

Magma forms ___ the Earth’s surface while lava forms ___ the Earth’s surface.

Below; On

A dike is a ___ intrusion while a sill is a ___ intrusion.

Vertical; Horizontal

Which igneous rock forms from solidified lava that comes onto the Earth’s surface and quickly cools to form small crystals?

Extrusive

Which igneous rock forms from magma that never reaches the Earth’s surface and solidifies underground to form large crystals?

Intrusive

Light colored igneous rocks contain mostly silica and small amounts of iron and magnesium. Which compositional group do they belong to?

Felsic

Dark colored igneous rocks contain high amounts of iron, magnesium, and calcium. Which compositional group do they belong to?

Mafic

What are the two types of intrusive rock textures?

Pegmatitic and Phaneritic

What are the four types of extrusive rock textures?

Aphanitic, Glassy, Porous, and Pryoclastic/Fragmental

Which igneous rock texture is both intrusive and extrusive?

Porphyritic

Which of the following is NOT part of the compositional layers of the earth?

Asthenosphere

New lithosphere is created at which plate boundary?

Divergent

A(n) ___ is created when an intense jet of heat melts part of the upper mantle.

Hot spot

A ___ is a naturally occurring homogeneous, solid formed by geologic processes that has an ordered internal arrangement of atoms, ions or molecules and has a composition that is defined by a chemical formula.

Mineral

According to the definition of a mineral, which of the following is not a property that all minerals exhibit?

Metallic

The streak of a mineral is the color of its ___.

Powder

The ___ of a mineral is a measure of how easily it can scratch or be scratched by other substances.

Hardness

Minerals are composed of rock fragments.

False

Minerals can be different colors because of impurities in the crystal structure.

True

__ occurs when the bonds holding atoms together are weaker in some direction than others.

Cleavage

__ fracture results in curved surfaces.

Conchoidal

Minerals’ color may vary, but the streak for all specimens will be the same.

True

Minerals containing the carbonate anion will react when HCI acid is dropped on them, such as calcite.

True

__ rocks form through the cooling and solidification of molten rock, which forms by melting preexisting rock in the mantle or lower crust.

Igneous

A(n) ___ igneous rock is formed from magma that never reached the Earth’s surface and slowly solidifies underground to form large crystals.

Intrusive

__ igneous rocks are light colored because they contain mostly silica and small amounts of iron and magnesium.

Felsic

Which of the following is not an extrusive igneous rock texture (i.e. not fine grained)?

Pegmatitic

Molten rock below the Earth’s surface is called lava.

False

__ is a horizontal igneous intrusion.

Sill