Geology Test 2

the columbia plateau in washington and oregon is _____

a flood basalt plateau

which of the following is true about rocks and minerals

a rock can contain more than one mineral, a mineral is composed of chemical elements, a single rock can include more than one mineral

which of the following best defines a mineral and a rock

a rock is a lithified or consolidated aggregate of different mineral grains

what denotes a basaltic lava flow covered with angular, congealed lava rubble

aa

Which of the following is the highest ranking, cleanest burning form of coal and is classified as a metamorphic rock?

anthracite

changing the composition of magma by incorporating surrounding host rock is known as

assimilation

What type of magma, commonly erupted along oceanic ridge systems, originates by partial melting of mantle peridotite?

basalt

a very large, discordant pluton commonly composed of granite

batholith

What is the most characteristic, original, depositional feature preserved in sedimentary rocks?

bedding

a nearly flat surface separating 2 beds of sedimentary rock

bedding plane

many limestones are

biochemical

_____ is a clastic sedimentary rock composed of predominantly angular, gravel-size particles

breccia

large volcanic depressions formed by subsidence and collapse are known as

calderas

term used to describe intrusive igneous masses that form parallel to the bedding of the surrounding rock

concordant

which of the following sedimentary rocks would you expect to have originally been desposited by fast-moving streams

conglomerate

what are sedimentary rocks

conglomerate and mudstone

which type of metamorphism occurs specifically in the heated zone around a pluton or other body of magma?

contact metamorphism

glassy igneous rocks form when the magma

cools so fast that mineral grains cannot crystallize and grow

a relatively small (under 1 km), summit depression on a volcano, marking a former eruptive vent, is a ?

crater

What term describes the complex, original stratification pattern seen in sandstones deposited in ancient sand dunes?

cross-bedding

the process whereby ions arrange themselves into orderly patterns during the cooling of a liquid is called

crystallization

Which tabular, discordant igneous rock body intrudes along a crack or fissure?

dike

a dike is a tabular, ______ type of pluton

discordant

a term used to describe intrusive bodies that cut across existing rock structures

discordant

the temple angkor wat in cambodia was built using laterite bricks. what is laterite

dried tropical rainforest soil

a sedimentary facies is the sedimentary rock's ____

environment of deposition

which of the following best describes bedded gypsum and halite

evaporates; chemical, sedimentary rocks

The sedimentary rocks salt and gypsum are deposited by what process?

evaporation

Large, dome-shaped structure, usually composed of granite, formed by sheeting.

exfoliation dome

igneous activity that occurs at the earth's surface

extrusive

term that describes rocks which contain high percentages of quartz and feldspar

felsic

An eruption in which lava is extruded from narrow fractures or cracks in the crust.

fissure eruption

what is not a common cementing agent for sandstines

fluorite

the linear arrangement of textural features often exhibited in metamorphic rocks.

foliation

the mechanical breakup f rock caused by the expansion of freezing water in cracks and crevices

frost wedging

what are the 4 most important physical processes of mechanical weathering

frost wedging, sheeting, thermal expansion, biological activity

Vents that emit only hot gases and vapors are called

fumaroles

Which of the following sedimentary features would typically be found in shales but not in sandstones

mud cracks

what mineral is a silicate

muscovite

which of the following minerals crystallize early in Bowen's reaction series

olivine

the micas, muscovite and biotite, both exhibit______ direction(s) of cleavage

one

Which variety of limestone consists mainly of sand-sized, mostly spherical grains of calcium carbonate precipitated in shallow, marine waters?

oolitic

Which form of chemical weathering specifically affects the iron contained in ferromagnesian, rock-forming, silicate minerals?

oxidation

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

oxides

which basaltic lava flow has a relatively smooth surface

pahoehoe

the rock from which a metamorphic rock was formed

parent rock

what term denotes the larger mineral grains in a porphyritic igneous rock

phenocryst

A mineral that is a good indicator of the metamorphic environment in which it formed. Used to distinguish different zones of regional metamorphism

index mineral

A mineral used to determine metamorphic grade is termed a(n) __________.

index mineral

igneous rock that formed below earth's surface

intrusive

which set of terms best describes an igneous rock in which you can clearly see the individual mineral grains comprising the rock

intrusive, phaneritic

what is the name given to an atom that gains or loses electrons in a chemical reaction

ion

the difference between ionic and covalent bonds is

ionic bonds are when atoms tare attracted electrostatistically due to positive and negative charges; covalent bonds are when atoms share the same electron(s)

red, brown, and yellow sandstones are cemented by oxides of ?

iron

Basalitc lava that solidifies in an underwater environment and is composed of numerous tube-like structures

pillow basalts

2 or more minerals having the same chemical composition but different crystalline structures

polymorphs

sandstone is a type of sedimentary rock that is classified based on its

predominant grain size

If you know the metamorphic facies of a metamorphic rock, what can you deduce about the rock?

pressure and temperature formation

A ________ texture refers to rocks composed mainly of mineral and volcanic fragments ejected during a violent volcanic eruption.

pyroclastic

what term describes fragmental volcanic material ejected during a volcanic eruption

pyroclastic

________ is a dangerous, fast moving, hot, turbulent cloud of volcanic gases and fine-sized, pyroclastic particles.

pyroclastic flow

Flint and jasper are microcrystalline forms of ________.

quartz

Under most weatheriqung conditions, which mineral component of granites and rhyolites would be most resistant to decomposition?

quartz

which mineral is composed of only silica

quartz

you are attempting to identify a mineral. you determine that it does indeed have cleavage; therefore, your mineral cannot possibly be:

quartz

associated with large-scale mountain climbing

regional metamorphism

which one of the following best describes volcanism in the cascade range, northwestern united states

related to plate subduction

the extrusive equivalent of granite is ______

rhyolite

what's the correct order of decreasing magma viscosity between: andesite, rhyolite, basalt

rhyolite, andesite, basalt

what igneous rock has a pyroclastic texture

rhyolitic tuff

Which of the following sedimentary features can each be used to determine paleocurrent directions

ripple marks and cross-bedding

which of the following does not correctly describe a mineral

it can be liquid or solid

which statement concerning mechanical weathering is not true

it involves a change in the mineral composition of the weathered material

a small igneous rock body emplaced at shallow depths by uplift and arching of the overlying, older strata

laccolith

another term for volcanic mudflow

lahar

the biggest dangers in composite type volanic eruption are

lahars (mudflows) and pyroclastic flows

magma that reaches earth's surface

lava

most common chemical sedimentary rock

limestone

The process of converting sediments to solid rock. (by cementation or compaction)

lithification

which response best represents the conditions of contact metamorphism

low pressures, shallow burial, and heat supplied by a nearby magma body

which of the following describes the light reflecting and transmission characteristics of a mineral

luster

term that describes basaltic rocks which contain high percentages of ferromagnesian minerals

mafic

what is the name given to molten rock below the earth's surface

magma

What two, metamorphic rocks are composed predominantly of single minerals?

marble and quartzite

What kind of weathering involves only a reduction in the sizes of bedrock and mineral particles?

mechanical

What is the dominant form of chemical bonding exhibited by minerals such as native gold, native copper and copper-rich sulfides?

metallic

Foliation in metamorphic rocks is mainly evident in the parallel alignment of certain mineral grains. What is the mineral?

mica

what strongly banded, metamorphic rocks show good evidence for having formed by partial melting?

migmatite

Felsic magmas/lavas are _____ viscous than basaltic magmas/lavas because they contain a _____ percentage of silica.

more...higher

small basaltic cones built during one, short, eruptive episode

scoria cones

if shale is such a common rock in the sedimentary rock world, why isn't it as prominently exposed at the surface as sandstone

shale crumbles easily, causing increased mechanical weathering, whereas sandstone resists weathering more effectively

oolitic limestone is most likely to form in what type of depositional environment

shallow, clear marine waters with vigorous current activity

A volcano composed of both lava flows and pyroclastic material; closely associated with convergent plate boundaries and subduction zones.

stratovolcano

what physical property denotes the color of a powdered mineral

streak

the 1991 pinatubo eruption in the philippines caused brilliantly colored sunrises and sunsets to be seen for the next few years. What caused this phenomenon

sulfur dioxide and other erupted gases formed aerosols in the stratosphere

how do you classify sedimentary rocks

texture and composition

lava flows are typically finer grained than intrusive igneous rocks. Why?

the extrusive magma cools quickly so the mineral grains do not have time to grow

which one of the following statements best describes erosion

the process by which weathered rock and mineral particles are removed from one area and transported elsewhere

what does bowen's reaction series describe

the temperatures at which different minerals crystallize out of a melt

what 2 factors speed up rates of chemical reaction and weathering in rocks and soils

warm temp. very moist

________ is the most abundant gaseous component dissolved in most magmas.

water

an inclusion of unmelted country rock in an ignous pluton

xenolith

mineral definition

in a mineral the constituent atoms are bonded in a regular, repetitive, internal structure

quartz is _____

-resistant to weathering and is an important component of sand in river beds and beaches -a main constituent of many igneous rocks -a main constituent of many sedimentary rocks -the most stable of all minerals at Earth's surface temp. and pressures

the ion at the center of a silicate tetrahedron is surrounded by

4 oxygen ions

in which setting would regional metamorphism be most likely

At great depths in the crust where two continents are colliding

what forms the best rock cleavage and why

Slate, because the grains are so small and so well intergrown that the rock is very strong and breaks along planes of fine micas.

One way in which sedimentary rocks are lithified. As material precipitates from water that percolates throughout the sediment, open spaces are filled and particles are joined into a solid mass

cementation

the weathering process by which the internal structure of a mineral is altered

chemical

what is a compact, microcrystalline sedimentary rock that was used by native americans to fashion projectile points (arrowheads), knives, scrappers, etc.

chert

a rather small volcano built primarily of ejected lava fragments

cinder cone

What mineral group forms by the breakdown and weathering of rock-forming silicate minerals and are important constituents of soils?

clay

a mineral property that can be observed without using a test is

cleavage

________ is composed mainly of lithified, organic debris that accumulated in ancient, heavily forested swamps?

coal

Sandstones are lithified mainly by cementation. What is the major process involved in the lithification of shales?

compaction

what is typically composed of alternating layers of lava and pyroclastic material

composite volcano

large, fairly steep-sided cones composed of lavas and pyroclastic layers

composite volcanoes

the volcanoes of southwestern alaska and the aleutian islands

composite volcanoes

what rock is likely to have the most quartz in it and why

granite, because it is an intrusive rock that formed from the cooling of relatively high silica magma

the matrix of smaller crystals within an igneous rock that has porphyritic texture

groundmass

Which evaporite sedimentary rock, composed of calcium sulfate, is an important component of plasters and wallboard?

gypsum

Moh's scale is a relative measure of which physical property of minerals?

hardness

what classes of rocks can be metamorphosed

igneous, sedimentary, and metamorphic

a broad gently sloping volcano built from fluid basaltic lavas

shield volcano

massive, gently sloping volcanoes built of successive, basaltic lava flows

shield volcano

the big volcanoes of hawaii

shield volcano

3 main types of volcanoes and 2 characteristics of each

shield, composite, cinder cone Shield- shape of a shield, runny lava composite- alternating layers, most violent type cinder cone- built from ejected lava fragments, lava flow comes out of the side

which are the most abundant minerals in Earth's crust and mantle

silicates

A structure composed of four oxygen atoms surrounding a silicon atom that constitutes the basic building block of silicate minerals.

silicon-oxygen tetrehedron

list rocks in increasing grade of metamorphism

slate, phyllite, schist, gniess

Which property of sediment describes the range of different grain sizes in a detrital sedimentary rock?

sorting

how do the electrons behave in a mineral with metallic bonding

they can move relatively easily from atom to atom inside the mineral