Geology final

Question 1

Understand the vastness of geologic time

Answer 1

Earth is 4.5 billion years old, human history is a small fraction of earths life.

Question 2

Be able to utilize superposition and cross-cutting principles

Answer 2

older rock is on the bottom, anything that cuts a sequence is younger than the sequence.

Question 3

dentify and understand three types of plate boundaries

Answer 3

Convergent, divergent, and transform. Convergent together and divergent away.

Question 4

Know the characteristics of the lithosphere and asthenosphere

Answer 4

lithosphere is the upper layer made of crust asthenoshpere is underneath soft molten

Question 5

Be able to explain how all three rock types are formed

Answer 5

Cooling of molten rock creates igneous rock. Combination of heat and pressure create metamorphic rocks and weathering plus erosion and deposition creates sedementary rocks.

Question 6

Understand the cations, colors, SiO2 content, etc. of mafic, and felsic rocks

Answer 6

Felsic is light colored with more silica and has the cations K, Na, and Al. Mafic is dark colored with less silica contains the cations Ca, Mg, and Fe.

Question 7

Understand the relationship between viscosity, SiO2, and explosivity

Answer 7

Magma that is high in silica is more viscosity and creat more explosivity

Question 8

Identify igneous rocks by their chemistry (mafic/felsic) and texture (aphanitic/phaneritic)

Answer 8

Granite, Diorite and Gabbro all phaneritic. Rhyolite andesite and basalt are aphanetic. Granite and rhyolite are felsic, Diorite andesite are intermediate, and Gabbro and basalt are mafic.

Question 9

Know the composition of oceanic and continental crust

Answer 9

Oceanic is composed of basalt and continental contains granite.

Question 10

Understand the difference between weathering, erosion,

Answer 10

Weathering is the destructive process that changes the physical nature or chemistry of the rock. Erosion is the removal of weathered material.

Question 11

Know the difference between mechanical and chemical weathering

Answer 11

Mechanical weathering is the breaking down of rock, chemical weathering involves a reaction decompostion of the mineral into something else.

Question 12

Understand chemical weathering’s relationship with water

Answer 12

Water contains acid which is the main agent in chemical weathering.

Question 13

Know the four products of weathering of minerals in Bowen’s series

Answer 13

Quartz, Iron Oxide, clay, and dissolved ions

Question 14

Know the detrital grain sizes and their resulting sedimentary rocks

Answer 14

Gravel size makes breccia and conglomerate, Sand size makes sandstone, silt size makes siltstone, and clay size makes shale.

Question 15

Know the compostion of limestone

Answer 15

Limestone can be easily dissolved by rainwater.

Question 16

Understand rounding and grain size and how they change with distance of transport from source area

Answer 16

The farther we go the smaller and more round the rocks become.

Question 17

Understand the differences (origin, textures, extent) between contact and regional metamorphism

Answer 17

Origin of contact metamorphism is heat from the magma body bakes the rock it touches, For regional tectonic forces squeeze rock and cause minerals to line up. Contact has non foliated textures while regional is foliated. Contact affects a much smaller area than regional.

Question 18

Understand how gradient affects stream velocity

Answer 18

More steep more velocity

Question 19

Understand the three ways a stream transports sediment

Answer 19

Disssolved load, Suspended load, and bedload

Question 20

Relate downcutting, base level, graded streams, and lateral erosion (

Answer 20

Base level is the level which a stream cannot downcut under, generally streams with a high base level tend to be doing more downcutting than lateral erosion. Streams with low base level will have more lateral erosion than downcutting.

Question 21

Understand what recurrence interval for a flood means

Answer 21

Gives a statistical probability of flooding in a given year.

Question 22

Know the difference between porosity and permeability

Answer 22

Porosity is the amount of holes and permeability deals with how fast water can move through the rock.

Question 23

Know and recognize on a diagram or sketch all groundwater zones (11). (the five zones: water table, confined aquifer, unconfined aquifer, saturated zone, unsaturated zone)

Answer 23

2

Question 24

Understand the formation of caves

Answer 24

Happens below the surface, when groundwater leaks through fractures in the limestone for the water to get in

Question 25

Know the main landform-shaping agent in deserts

Answer 25

Water

Question 26

Know & ID desert features of the Colorado Plateau

Answer 26

Canyons, Plateaus, Buttes, and Mesas.

Question 27

Understand longshore current, longshore drift, and their causes

Answer 27

Longshore current refers to the water drift refers to the sand being moved by that water. Happens when the waves hit the shore at an angle.

Question 28

Know the source and mineralogy of most beach sand and why

Answer 28

Rivers carry the sand from weatherd areas to the ocean. Mostly made up of quartz.

Question 29

Know the different types of stress (and what they do to crust) and strain

Answer 29

Compressive, Tentional, and Sheer. Compressive stress squeezes and the crust becomes shorter and thicker. tentional stress makes the crust longer in the horizontal dimension and shorter vertically. Sheer stress does neither. Compressive for convergent, divergent is tentional, and transform is sheer. Reaction will either be elastic, brittle, or ducktile.

Question 30

Understand strike and dip and be able to read them on a geologic map

Question 31

Identify folds from descriptions AND on a geologic map

Answer 31

Dip reversal indicates a fold if fold is anticline then arrows point away from the fold. Sincline is indicated by the arrows pointing towards eachother.

Question 32

estuary,

Answer 32

Drowned river mouth.

Question 33

brackish,

Answer 33

mix of salt and fresh water.

Question 34

barrier island

Answer 34

Ridge of sand paralleling the shoreline and extending above sea level.

Question 35

dentify from a description AND diagram all types of faults discussed and hanging wall/footwall(15). (normal, reverse, left-lateral strike slip, right-lateral strike slip)

Answer 35

Top heavy is the footwall bottom heavy is the hanging wall. Normal fault the hanging wall moves down Tensional. Reverse fault is the result of compression stress hanging wall moves up. Both strike slip faults are sheer stress at transform boundaries.

Question 36

Be able to relate a structure to the type of stress that formed it

Answer 36

Folds are the result of compressive stress, reverse faults are the result of compressive stress, normal faults are tensional stress and strike slip faults are sheer stress.

Question 37

Understand what an unconformity is

Answer 37

A surface that represents a break in the geologic record, with the rock unit immediately above it being considerably younger than the rock beneath.

Question 38

Know the 3 types of seismic waves and differences between them (16). P, S, surface

Answer 38

p waves are the fastest, s waves are the second fastest but can’t go through water, surface are the most damaging to the land.

Question 39

Understand the difference between quake intensity and magnitude

Answer 39

Magnitude is the energy released by the earthquake, intensity is what it does to buildings and people.

Question 40

Know the worldwide distribution and causes of earthquakes

Answer 40

Most occur at plate boundaries

Question 41

Understand the accuracy of earthquake prediction

Answer 41

Not that good at prediction

Question 42

Match metals to their common ore sources

Answer 42

Iron comes form hematite magnetite creates steel. Copper is from chalcopyrite and us used in electricity and brass. Aluminum comes from bauxite used in everything. Lead comes from galena, used in batteries. Zinc is found in sphalerite and us used to galvanize brass and steel. Silver is a byproduct of zinc mining, used mainly for jewelry and tableware. Gold is a natural element used for electronics, coins and jewelry.

Question 43

Describe the three elements necessary for petroleum deposits

Answer 43

Exploitable petroleum resources require a carbon-rich sourcerock (often shale), a permeable reservoirrock (oft. sandstone), and a low-permeability traprock (oft. shale) to halt migration of petroleum to the surface

Question 44

Explain possible causes of + and – magnetic (Fe) and gravity (mass) anomalies

Answer 44

Magnetic anomalies have to do with total iron and gravity deals with total mass.

Question 45

Explain isostatic crustal responses to deposition and erosion

Answer 45

Sink as more weight is added and rise as weathering and erosion takes place.

Question 46

Explain the significance of the P-wave and S-wave shadow zones.

Answer 46

P-wave shadow zone shows us the location of the core mantle boundary, the s-wave shows us that the core is liquid.