Geology Exam 2

Question 1

Flood basalt eruptions are fed by..?

Answer 1

long fissures/dikes

Question 2

how was the crater at crater lake formed?

Answer 2

collapse of overlying rocks into an emptied magma chamber

Question 3

when melting forms magma…

Answer 3

partial melting produces a magma that is more felsic than the source

Question 4

Which of the following is Not a rock typically found with calderas?

1. welded rhyolite
2. tuff
3. granite
4. gabbro

Answer 4

gabbro!

Question 5

how do volcanic neck forms

Answer 5

1. erosion of the volcano, leaving behind the solidifed conduit inside the volcano
2. erosion of overlying rock layers exposing the conduit below the volcano

Question 6

This is the solid upper part of the Earth, including the crust and uppermost mantle

Answer 6

lithosphere

Question 7

what class of mineral forms when the element O is bonded with a metal, as in the mineral hematite?

Answer 7

oixdes

Question 8

what are the two main ways that minerals are put together in rocks?

Answer 8

crystalline verus clastic

Question 9

magnetite and hematite occur together in layered sedimentary rocks called?

Answer 9

banded iron formations

Question 10

what type of mineral is garney?

Answer 10

silicate mineral

Question 11

what class of mineral form when the element Si is bonded with element O, as in the mineral quartz?

Answer 11

silicates

Question 12

what is composed of the smallest sedimentary clasts?

Answer 12

shale

Question 13

which of the following is a common characteristic of carbonate rocks?

Answer 13

they commonly have a dissolved apperance

Question 14

because shales are easily eroded, the areas where they are exposed typically

Answer 14

have soft slopes and soil cover

Question 15

how does an angular unconformity form?

Answer 15

older rocks are tilted, eroded, and overlain by younger rocks

Question 16

what lived during the Mesozoic era?

Answer 16

dinosaurs

Question 17

oldest rocks found are from the

Answer 17

precambrian era

Question 18

what is punctuated equilibrium

Answer 18

a hypothesis that explains how new organisms or new characteristics can appear suddenly in the fossil record

Question 19

James Hutton came up with..

Answer 19

the concept that geologic processes operating at present are the same processes that operated in the past

Question 20

oceanic plateaus form from basaltic volcanism originating from

Answer 20

hot spots

Question 21

the majority of transform boundaries are found

Answer 21

in conjunction with mid-ocean ridges

Question 22

what is the ultimate source of food for animals living around deep-sea hydro thermal vents

Answer 22

bacteria that break down hydrogen sulfide

Question 23

most oceanic plateaus are..

Answer 23

constructed by volcanic eruptions probably over mantle pumes

Question 24

forms in low-temperature environments, at or near Earth’s surface

Answer 24

Clastic

Question 25

forms in high-temperature environments; minerals are interlocking

Answer 25

crystalline

Question 26

A rock that is unusually rich in some commodity that might be valuable

Answer 26

mineral deposit

Question 27

contains enough of a commodity to be mined at a profit

Answer 27

ore deposit

Question 28

contains (CO3)^2

Answer 28

carbonates

Question 29

calcite and dolomite

Answer 29

carbonates

Question 30

contains oxygen bonded with metals

Answer 30

oxides

Question 31

contains (S)^2 bonded with Fe, Pb, Zn, or Cu

Answer 31

sulfides

Question 32

pyrite and galena

Answer 32

sulfides

Question 33

contains (S04)^2 plus an element like Ca

Answer 33

sulfates

Question 34

gypsum

Answer 34

sulfates

Question 35

contains a metallic element, such as Na or K

Answer 35

Halides

Question 36

is the percentage or concentration of the valuable commodity in a rock

Answer 36

the grade

Question 37

CaSO42H2O, can be scratched with fingernail; typically gray, white, or clear

Answer 37

gypsum

Question 38

PbS; distinctive metallic-gray cubes with cubic cleavage; high specfic gravity

Answer 38

Galena

Question 39

FeS; pale bronze to brass-yellow; commonlu forms cube-shaped crystals

Answer 39

Pyrite

Question 40

what is detritus

Answer 40

is loosened and transported clastic material

Question 41

detrital

Answer 41

describes deposits of detritus

Question 42

this occurs when rocks are heated locally and have little associated deformation

Answer 42

contact metamorphism

Question 43

involves heating and deformation over large areas

Answer 43

regional metamorphism

Question 44

granite and rhyolite are

Answer 44

felsic

Question 45

diorite and andesite

Answer 45

intermediate

Question 46

basalt and gabbro

Answer 46

mafic

Question 47

peridotite

Answer 47

ultramafic

Question 48

rock made mostly of calcium carbonate; may contain fossil shells and coral skeletons

Answer 48

limestone

Question 49

very soft rock of calcium carbonate created by remainns of mirco organisms

Answer 49

chalk

Question 50

mostly forms when seawater evaporates in tidal flats and narrow seas; the material in sheetrock

Answer 50

gypsum

Question 51

conglomerate

Answer 51

rounded pebbles and sand and finer particles between larger clasts

Question 52

Breccia

Answer 52

angular pebbles and coobles and finer particles between larger clasts