Geology questions exam 2

what is the difference between magma and lava

they are both molten rock material, but magma is below the land surface and lava is above the land surface.

T or F: A lahar is a volcanic mudflow.

true

T or F: Due to the particle size being larger, stream gravel needs a swift current to be transported whereas sand needs a current with less energy.

true

T or F: Igneous rocks can have special textures. For example, a porphyritic texture has two different minerals sizes which indicates two different cooling rates.

true

T or F: Kilauea is a volcano created by intraplate (hot spot) volcanism

true

T or F: Three volcanic landforms are vents, craters, and calderas.

true

T or F: Weathering/Erosion and uplift are two examples of surficial Earth processes.

true

T or F: an extrusive rock is an igneous rock that occurs at Earths surface

true

T or F: sills are igneous intrusive bodies that form parallel to bedding

true

____________ is a collective term for all of the chemical, physical, and biological changes that take place after sediments are deposited and during and after lithification.

Diagenesis

Igneous rock composition is categorized as:

Mafic (basaltic), intermediate (andesitic), felsic (granitic)

What is the first or uppermost soil horizon

O

The primary basis for classifying detrital rocks is ________ whereas the primary basis for classifying chemical rocks is ________.

Particle size; mineral composition

What is the difference between marble and quartzite?

Quartzite is composed of the mineral quartz; marble is composed of the mineral calcite

A rock with a gneissic texture is characterized by __________.

a banding of light and dark minerals in a metamorphic rock

the 3 major components of magma include

a liquid, a solid, and a gaseous component.

In terms of silica context, ___________ basaltic lava has a more complex structure

a'a

An igneous rock/magma with a mafic composition will be characterized by __________.

abundant ferromagnesian minerals

All of the following are means of melting rocks on earth except __________.

addition of organic matter to rock

wind blown deposits of sediment are

aeolian

The chemical formula Al2SiO5 can form any of these three minerals, given different combinations of temperature and pressure conditions:

andalusite, kyanite, and sillimanite

Which of the following is a soft, black coal that forms when organic matter (plants) experience significant burial and compaction?

bituminous

Confining pressure dominates in areas where ____________ is happening.

burial metamorphism

__________________decomposition of rock from exposure to atmospheric gases (oxygen, water vapor and carbon dioxide)

chemical weathering

_________________________ small, steeply sloping, and composed of a pile of loose cinders.

cinder cone volcano

Which of the following textures defines a slate?

cleavage

Volcanoes associated with a subduction zone are likely to be _________________

composite volcanoes

what differentiates a conglomerate from a breccia?

conglomerates have rounded grains of gravel, indicating a long transport distance

__________________describes the tendency for different types of rock to weather at different rates

differential weathering

___________ involves the changing of magma composition by the removal of denser early-formed ferromagnesian minerals by crystal settling

differentiation

_________________the chemical breakdown of rocks due to acidic water/solution

dissolution

Violence of eruptions is controlled by

dissolved gases

________________physical picking up of rock particles by water, ice, or wind

erosion

The minerals gypsum and halite form in lake or lagoon environments that are subject to arid conditions. Which variety of chemical sedimentary rock do they form?

evaporites

Dark, poorly sorted sandstones with angular clasts are called arkose and are often associated with turbidity currents.

false

T or F: Divergent plate boundaries are where we find most felsic volcanism.

false

T or F: Extrusive igneous rocks are coarse grained.

false

T or F: Intrusive, phaneritic, and glassy are all terms that describe volcanic textures

false

T or F: Partial melting of andesite generates a magma with an ultramafic composition

false

T or F: There greatest hazard associated with volcanoes is the risk of getting caught up in a lava flow

false

Which texture forms in areas of mountain-building?

foliated

Sedimentary rocks are the main family of rocks that contain ____________.

fossils

Which of the following methods of transportation will result in the poorest sorting?

glaciers

Which primary sedimentary structure is most closely associated with turbidity currents?

graded bedding

the intrusive and extrusive, felsic igneous rocks are

granite and rhyolite

What is the driving force behind pyroclastic flows?

gravity

Rates of chemical weatering are fastest in regions characterized by __________.

high temperatures and high humidity

The complex process whereby silicate minerals such as feldspar are broken down to make clay minerals by reacting with water molecules is ___________________________________.

hydrolysis

What type of metamorphism would be most likely occur adjacent to a hot spring?

hydrothermal metamorphism

Serpentinite is a metamorphic rock that results from the __________.

hydrothermal metamorphism of oceanic crust

sedimentary rocks form

in horizontal layers on Earth surface

Metamorphism of a rock can result from __________.

increase of pressure and temperature, exposure to reactive chemical fluids

Mechanical weathering can increase the rate of chemical weathering by ___________.

increasing the exposed surface area of a rock

When magma solidifies (cools) it hardens to form an igneous rock. Igneous rocks like all other rocks can be classified in terms of their texture and composition. Texture for igneous rocks can be classified as either ________________________ or _________________________. Each of these textures is determined by how fast or slow the magma cooled.

intrusive, extrusive

The name for a volcanic mudflow is:

lahar

The worst type of soil is found in the tropics is:

laterite

Materials extruded by eruptions are categorized as:

lava, gases, and pyroclastic (solid fragments)

What is the protolith of marble?

limestone

Flood basalts would have _________________ viscosity.

low

Igneous rock composition however is dictated by the amount of silica present in the rock. Low silica content results in a _________________________ or dark composition.

mafic (basaltic)

Lavas erupting from composite volcanoes are generally ________-rich, making them very viscous

silica

A metamorphic rock whose parent rock was a limestone is referred to as __________.

marble

____________________physical disintegration via frost action, pressure-release fracturing, plant growth, burrowing animals, salt wedging, thermal cycling

mechanical/physical weathering

An extremely hot metamorphic rock may begin to ___________, producing the rock called _______.

melt; migmatite

An igneous rock with an aphanitic texture will be characterized by __________.

minerals that can only be observed with the aid of a microscope

Which primary sedimentary structure would indicate exposure to the air?

mud cracks

topsoil is composed of which soil horizons?

o and a horizons

___________ are tiny inorganic particles created when small sediments or shell fragments are rolled by waves in warm water supersaturated with calcium carbonate. Layers of CaCO3 accumulate around this "nucleus" to make a concentrically-zoned structure, like a hailstone or a jawbreaker.

ooids

___________________describes the process of chemically active oxygen from the atmosphere combining with a rock surface material resulting in the formation of iron oxides

oxidation

the runniest/fastest/least viscous type of lava is

pahoehoe

Dikes are igneous intrusive bodies that form __________________ to bedding

perpendicular

Metamorphism of a shale at a low metamorphic grade produces which of the following metamorphic rocks?

phyllite

A sedimentary rock that contains a mixture of large and small particles is __________.

poorly sorted

________ is the name given to the mix of pulverized rock, lava fragments, and ash erupted from a volcano

pyroclastic materials

Which sedimentary rock is most likely to represent deposition on a beach?

quartz sandstone

Which group of three minerals are the most common minerals in sedimentary rocks?

quartz, clay, calcite

One type of non-foliated metamorphic rock is __________.

quartzite

Pillow basalts are most likely to be associated with a(n) _________________________

seamount

Which of the following can contain fossils?

sedimentary rocks

Oolitic limestone forms in what depositional setting?

shallow marine

Which of the following lists puts metamorphic rocks in the order of increasing grain size (and increasing grade of metamorphism)?

slate, phyllite, schist

What are the three major components of all magma?

solid, melt, and volatiles

_______ describes the range in particle sizes in a detrital sedimentary rock.

sorting

________________________ occurs where rock has been rounded by weathering from an initial blocky shape

spheroidal weathering

What tectonic process is implied by blueschist?

subduction

Which environment would be likely to produce a black shale?

swamp

Small glass droplets produced as a result of meteorite impact melting are _____.

tektites

Foliation is a common texture in many metamorphic rocks. What is foliation?

the preferred allignment of elongate or platy minerals, or the banding of mafic and felsic minerals

What is the name for the holes in this basalt? How did they form?

vesicles, they form when the lava degasses upon eruption, forming bubbles

________ is a material's resistance to flowing

viscosity

________________________ is a type of eruption with low viscosity, large volume, and creates lava plateaus.

volcanic dome

Which of the following sequences of processes is the correct order that would lead to the formation of a sedimentary rock?

weathering, erosion, transportation, deposition, lithification