Sedimentary Rocks & Weathering Processes

shale

the type of sedimentary rock that makes up the most of the earths crust

shale sandstone limestone dolomite

types of sedimentary rocks that make up the earths crust

clastic nonclastic

sedimentary rocks are broken up into 2 types of rocks

clastic

composed of pre-exsiting rocks

non clastic

formed by chemical or biological precipitates

conglomerate

Clastic rock made from gravel

sandstone

clastic rock made from Sand

siltstone

clastic rocks made from silt

limestone

this type of sedimentary rock forms sinkholes

shale

clastic rock that is made from clay

limestone and gypsum

non clastic rocks formed by chemical precipitate

coal and limestone

non clastic rock formed by biological precipitates

mechanical weathering

type of forming process for clastic rock, includes the physical breakdown of rocks

mechanical weathering

earthquakes, human/animal activity, water freezing in rocks are examples of

chemical weathering

type of forming process for clastic rock, is focused on the reaction with water

chemical weathering

carbonation, oxidation and hydrolysis are examples of

transportation

A clastic rock forming process that involves natural energies like gravity and wind

gravity water wind

3 main factors of the transportation clastic forming process

deposition

the transformation forming process results in _______ (clastic rock)

Colluvium

Gravity causes this kind of deposition

Alluvial

River causes this kind of deposition

glacial

Ice causes this kind of deposition

aeolian

Wind causes this kind of deposition

compaction cementation crystallization

the 3 lithification transformations of sediments into sedimentary rocks

compaction

individual particles, deposition one on top of another caused by over burden pressure (type of transformation of sediments)

cementation

the individual particles that are deposited and water seeps through and cements minerals (silica, CaCO3) is called

cyrstallization

this transformation of sediments occurs in non-clastic rocks

weathering

the mechanical breakdown and chemical alteration of rock material during exposure to air, moisture and organic matter

dry

mechanical weathering occurs in ____ climates

humid

chemical weathering occurs in _____ climates

structural stability

an engineering importance of weathering

frost wedging

when water expands when freezing resulting in stress increase; promotes mechanical weathering

stress relief

loading causes settlement; stress release causes heaving; also known as exfoliation (type of mechanical weathering)

thermal events

fire or lighting that can cause localized heating (type of mechanical weathering)

biological activity

humans, animals, plants (type of mechanical weathering)

salt weathering

type of mechanical weathering as a result of Na

Abrasions

particle movements that cause this is a type of mechanical weathering

chemical

this type of weathering requires the presence of water

hydrolysis

when the presence of water changes one mineral into another; a type of chemical weathering

hydration

adsorption of water with in the lattice structure; type of chemical weathering

carbonation

reaction with CO2; type of chemical weathering

oxidation

combining with oxygen; type of chemical weathering

leaching

infiltration of meteoric water and weathering of minerals; type of chemical weathering

water

____ makes a great solvent for chemical weathering

arid

from mechanical weathering —> sharp angular featured topography

humid

from chemical weathering —> rounded topography due to this climate type

humid

Rock: Granite → Mineral: quartz → weathering: XX → product: clay, oxides, pieces of quartz

arid

Rock: Granite → Mineral: quartz → weathering: XX → product: pieces of quartz

humid

chemical weathering climarte condition that requires water

porosity, permeability

weathering increases the ______ and ______

strength, density

weathering decreases the ______ and ______

gravity

agent of erosion/transportation the deposits COLLOVIUM

wind

agent of erosion/transportation the deposits AEOLIAN

Dunes

example of Aeolian deposit

River

agent of erosion/transportation the deposits ALLUVIAL

Lake

agent of erosion/transportation the deposits LACUSTRINE

Till

example of glacial deposit

river delta

example of erosion/transportation from stream to shallow part of ocean

shallow

river delta is due to the transportation of a river/stream to what part of the ocean

lithification

the transformation of sediments (individual particles) into rocks

lithification

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occurs in 3 ways: compaction, cementation, crystallization

compaction

occurs due to overburden pressure from material above (lithification)

shale

clay turns into ____ ; due to compaction

siltstone

silt turns into ____ ; due to compaction

sandstone

sand turns into ____ ; due to compaction

limestone

lime mud turns into ____ ; due to compaction

bituminous coal

peat turns into ____ ; due to compaction

conglomerate

gravel turns into ____ ; due to compaction

cementation

deposition/precipitation of soluble material from ground water (bind the particles together)

silica caco feo

these are typical cementing agents

crystallization

due to high pressures the original mineral can redevelop into new minerals which are more stable under the new conditions

crystallization

this type of lithification is more common in non-clastic rocks and has an interlocking structure

texture

particle size, particle shape, particle arrangement, way to identify sedmentary rocks

composition

mineralogy, type of identification that is useful for non clastic rocks because its made up of only one mineral

USC

the classification system we use to identify particle size

particle size

the unified soil classification helps us determine

far away

if the particle shape is rounded, the source was

closeby

if the particle shape is angular, the source was

layered

the particle arrangement for clastic rocks are usually

clastic

_____ rocks are layered because they are deposited from erosion products

non clastic

particle arrangement for _______ rocks are grains of interlocking

sorting internal

2 ways to identify sedimentary rock features

sorting

refers to the range of particle sizes

poorly

if well sorted then _____ graded

well

if poorly sorted then _____ graded

well

if sedimentary rocks are wind laid then it is considered to be ____ sorted

wind

environmental factor that usually results in well sorted

glaciers

environmental factor that usually results in poorly sorted

poorly

if water laid —→ rapid fluctuation in velocity = ______ sorted

well

if water laid —> slow fluctuation in velocity = _____ sorted

bedding planes

sedimentary internal structure, most predominant feature of sedimentary rocks

parallel

type of bedding plane that results due to deposition in standing water; transports sediments by currentsc

cross

type of bedding plane formed due to currents and shows current direction

graded

type of bedding plane with gradual change in grain size

currents

cross bedding is formed due to

ripple marks

sedimentary internal feature formed by action of currents and waves

current

ripple marks can show the type and direction of ______

wave and current

the types of ripple marks

wave

ripple mark formed by back and forth sloshing

current

ripple mark that can tell you the _______ direction