Geology Big Quiz - Sedimentary Rocks

10.How big are gravel-sized particles?

( >2mm)

11.How big are sand-sized particles?

(1/16mm to 2 mm)

How big are silt-sized particles?

(1/256 to 1/16 mm)

How big are clay-sized particles?

(< 1/256 mm)

9.What is the type of sedimentary rock that is composed primarily of gravel-size particles

Conglomerate/Breccia

8.What is the category of sedimentary rocks that are composed of the broken and worn particles of older geologic materials that have been deposited by wind or water?

Detrital

Sedimentary layers can be formed by:

[a] clastic or detrital particles (e.g., sand grains, shells, bones, clay mud and so on), [b] minerals that have precipitated out of a water-based solution, or [c] materials erupted from a volcano

Ice occupies more ____ when it is ____ than when it is ____, and can exert a tremendous _____ on any rock crack as it passes from ____ to _____ ice.

Volume; frozen; liquid; stress; liquid; solid

Siliciclastic sediments

broken fragments of silicate rocks and mineral grains

How might sediment be transported?

by suspension in the transporting medium (air or water) if the particles are very small, or saltation, or by rolling and sliding along the bed surface.

Common minerals in carbonate sediments

calcite, dolomite, clay (a silicate mineral family), and various iron, magnesium or aluminum oxides.

Chemical Weathering

dissolving calcite-rich rock by exposure to acids in the environment

common non-marine depositional environment

dunes, mountains

16.What is the general name of sedimentary deposits formed under conditions of high evaporation?

evaporites

7.Does the volume of a mass of water stay the same, contract or expand as it passes from the liquid to the solid state?

expands

How do Sedimentary rocks form?

from particles accumulated in sedimentary layers

What do Sedimentary layers contain?

geohistorical information

Gravel grain size ranges from small to large:

granules to pebbles to cobbles to boulders

15.What is the name of a sedimentary deposit formed under conditions of high evaporation and composed of hydrous calcium sulfate (CaSO4.2H2O)?

gypsum

14.What is the name of a sedimentary deposit formed under conditions of high evaporation and composed of sodium chloride?

halite

Shale

has a layered fabric (shaley cleavage or shaley parting) and is composed of silt and clay

What indicates that a grain has not been transported a significant distance

if they're Angular grains (sand size and larger) compared to rounded grains

When is ice wedging most active?

in the spring and fall, when daytime temperatures are above freezing and nighttime temperatures are below freezing.

What does Jointing or cracking of a rock do?

increases it's surface area

What is the economic importance of sedimentary rock?

it's the source of valuable commodities such as [a] building materials such as sand, gravel, decorative stone, clay for bricks; [b] energy resources such as oil, gas, coal and uranium; and [c] economic minerals such as iron, placer gold, bauxite and so on.

a common marine depositional environment.

ocean floor, rivers, lakes

How do cross-beds form and what do they allow us to do?

on the steep down-current face of a ripple mark or dune, and allow us to interpret the direction of (paleo-)current flow.

Common minerals in siliciclastic sediments in order of importance

quartz, clay, mica, minor feldspar, rock fragments, and dark "ferromagnesian" minerals like biotite, amphibole and pyroxene.

17.What sort of bedding develops as particles move in wind or water currents, forming ripple marks or dunes?

sand beds

20.What is the type of sedimentary rock that is composed primarily of sand-size particles?

sandstone

Mechanical Weathering

separating rock particles from the source through frost wedging

21.What is the type of sedimentary rock that is composed primarily of silt-size particles?

shale

18.What sort of bedding develops as particles of different sizes settle out of turbulent sediment-laden water as it loses velocity?

shale beds

depositional environment along the coastline of an ocean.

shoreline, lagoon, reefs

22.Which is bigger: clay-sized or silt-sized particles?

silt

Ripple marks and dunes are created as a result of?

the flow of sediment-laden wind or water

Breccia

type of conglomerate with mostly angular gravel sized particles

5.What geologic process involves the breakdown and alteration of rocks at Earth's surface through interaction with water and the atmosphere?

weathering

1.What are the major steps in the development of a typical clastic sedimentary formation?

weathering, erosion, transportation, deposition, burial, compaction and cementation. Compaction and cementation are the primary processes in the lithification of a sedimentary rock.

Conglomerate

A sedimentary rock composed largely of gravel sized

Carbonate sediments are composed primarily of the minerals:

Calcite & Dolomite

Calcite

Calcium Carbonate

Dolomite

Calcium Magnesium Carbonate

2 types of weathering processes:

Mechanical & Chemical

Why is sedimentary rock important?

[a] it forms the interface between the solid Earth and the biosphere, hydrosphere and atmosphere; [b] it contains much of the evidence of Earth's biological and climatological history; and [c] it is economically important.

Factors affecting chemical weathering include:

[a] temperature; [b] precipitation; [c] vegetation; and [d] industrial pollution.

The composition of clastic sediment is primarily a function of

[a] the composition of the source material from which the sediment was derived, [b] the distance the sediment has been transported -- the greater the distance, the higher percentage of quartz and other chemically stable minerals

The history of a sedimentary grain includes:

a] physical or chemical weathering, [b] dissolution or erosion -- separating the compound or particle from its original source material; [c] transportation by wind, water, ice; [d] precipitation or deposition; [e] burial and possible lithification.

12.What is the name of the sedimentary rock formed by micro-crystalline quartz?

chert

minor feldspar weathers easily to

clay minerals, silica in solution, and various salts

grain sizes from small to large:

clay, silt, sand, gravel

rock sizes from small to large: (corresponds w/ grains)

claystone, siltstone, sandstone, conglomerate

Mudstone

composed of silt and clay, but doesn't necessarily have the obvious layered fabric of shale.