GEO 303 SHANAHAN UT EXAM 1

What is the age of Earth?

4.5 Billion years, or Ga

How do we know the age of the Earth?

Dated meteorites, dated moon rocks, dated zircons in Austrailia

What is the age of the Universe?

13.8 billion years, or Ga

How do we know the age of the Universe?

Estimated through the examination of galaxies' velocity and distance

What elements were initially created with the Big Bang?

Hydrogen(H) then in the following minutes Helium(He), Beryllium(Be), and Lithium(Li)

What elements are in the Core?

Iron(Fe) and Magnesium(Mg)

What elements are in the Mantle?

Magnesium(Mg), Iron(Fe), Silicon(Si) and Oxygen(O)

What elements are in the crust?

Silicon(Si), Aluminium(Al), and Oxygen(O)

What are the possible ways earths atmosphere was formed?

Volatiles from volcanoes, and elements deposited by Comets

What did Alfred Wagner hypothesize about continental drift? What issue did he have?

He created the idea of Pangea. He used cross analysis of climate belts, matching geologic units, and fossil distribution to make his claim.

BUT he had no way to prove how exactly they moved

What is paleo-magnetism?

Analysis of the declination and inclination of magnetic minerals in rocks that have cooled past the Curie point

What type of igneous rock is the Crust?

Felsic and Mafic

What type of igneous rock is the Mantle?

Ultramafic

Lithosphere

Crust and upper Mantle

Asthenosphere

The soft layer of the mantle on which the lithosphere floats.

What does a Divergent Boundary create?

New Lithosphere, continental rift valleys, Mid ocean ridges

What does a Convergent Boundary create?

Ocean trench, Compressional mountains, consumes lithosphere

What does a transform Fault create?

Geologic Transform fault, Lithosphere conserved

igneous rock formation

Rocks crystallized from lava melt

Sedimentary rock formation

formed from break down of parent rock

Metamorphic rock formation

re-crystallization of igneous or sedimentary rock WITHOUT melting

Quartz formula

SiO4

Olivine formula

(Mg,Fe)2SiO4

Halite formula

NaCl

How are glasses defined?

They have no internal atomic order

Isostructural minerals

Minerals with the same geometry or structure but different chemistry

Polymorphic Minerals

Minerals with the same chemistry but different geometry

What are the most common elements in the Crust?

O, Si, Al, Fe, Ca, Na, K, Mg

Ionic Bond and mineral description

weak bond, metal with nonmetal, electron theft, soft, sometimes water soluble

Covalent Bond and mineral description

Strong bond, two nonmetals, sharing electrons, hard

Van der Waals bond and mineral description

Very Weak, soft, residual electron charges

What is the most common mineral?

Silicates

where are Silicates found

crust and mantle

What defines Framework silicates

All oxygen are shared strongly with no cations

What are the two Carbonate groups

Calcite and Aragonite groups

Whats one purpose that Oxides and Sulfides serve?

Host phases for metals

Mafic description

Rich in Fe, Mg, dark, dense, low gas content, high melting point

Felsic/Silicic Description

Rich in Si, Al, K, Na, light, not dense, high gas content, low melting point

Decompression Melting

As pressure decreases but temperature remains constant the rock expands while volatiles break chemical bonds

What rocks are formed by a mid-ocean ridge?

Pillow Basalt(on top), Gabbro(underneath)

What is Moho?

boundary between crust and mantle

What type of volcano is created by sinking lithosphere

Andesitic stratovolcanes