Geomorphology Midterm UGA October 8th

Glacial Interglacial Cycles

Periods during during the Quaternary period where the Earth would enter glacial periods and interglacial periods. Glacial periods had glaciers going oftern to illinois and wisconsin, currently in an interglacial.

Quaternary Period

the latest 2.6 million years, very important period for landscape development

radiocarbon

dating method used carbon 14

cosmogenic nuclides

dating method showing how long a surface has been exposed for

Luminescence

dating method based on how long quartz/feldspar has NOT been exposed to light (how long has this sand been buried and stable)

dendrochronology

based on rings of tree (VERY FUCKING ACCURATE AND AWESOME)

Potassium Argon Dating

dating lava flows and tephra (similar to radiocarbon cause of the radio part)

Weathering rinds

ring of weathered rock around rock that indicate exposure

cesium 137

only started existing when they dropped the first atomic bomb, shows if something was formed before or after 1963

18 oxygen

proxy for global average temperature, but represents global ice volume

2 parts of the quarternary

pleistocene and holocene (last 11,700 years of 2.6 million years)

eccentricity, obliquity, precission

3 extraterrestrial drivers of climate change

eccentricity

obliquity

precision

lake bog marine sediments, ice cores, stalagmites

continous long term records of a changing climate

loess

periglacial or windborne sediment (deposits can show record of glaciers)

true

true or false:

Many parts of the world are forecast to have increased landslides, largely because warmer air

silicates

silicon + oxygen

Carbonates

calcite, dolomite, agricultural lime and concrete

Sulfates

gypsum, drywall

sulfides

pyrite and metals

halides

SALT

Oxides

hematite

magnetite

rutile

metals adn paint

Intrusive Igneous

cooled below surface cooled slowly, coarse

Extrusive igneous rock

Cooled above the surface

cooled quickly ; fine grained

FELSIC

rich in FELDSPAR and SILICA

MAFIC

rich in MAGNESIUM and IRON

Batholith

MASSIVE intrusive body (stone mountain)

Stock

smaller intrusive body

sill

intrusive LAYER concordant with strata

Dike

intrusive layer that CUTS THROUGH strata

Laccolith

intrusive layer that pushes overlying strata to form a dome (think big pimple

columbia plateau

basalt lava plateau (pacific northwest)

Lithification

process of sediments turning into rocks

clastic sedimentary

rock made from particles of other rocks

nonclastic sedimentary

formed from evaporation of chemical solution or from organic deposition (coal

conglomerate

poorly sorted clastic rock

shale

fine grained muds and clays

stratification

layering of sedimentary rock

landforms of flat lying sedimentary rocks

plateus mesas buttes pinnacles

contact metamorphism

rock changed by ONLY heat

foliated

layered

quartzite og form

sandstone

gneiss og form

granite

radon

gas sneaking into your house to kill you

continental crust

the crust that is thick and felsic

oceanic crust

thin crust that is mafic

lithosphere

rigid and made of crust and uppermost mantle

asthenosphere

plastic and flows readily

orogeny

wegener

guy who made pangea, wasnt believed until the 1960s

earthquakes volcanoes and mountain ridges MOSTLY happen on plate boundaries

where does volcanoes and earthquakes mostly happpen?

Isostasy

equilibrium between floating landmasses and denser rock beneath them, think iceburg. thicker the crust, deeper its roots and higher it stands.

isostatic readjustment

erosion of mountain will make crust thinner and then mountain readjust upward

glacio-static rebound

icebergs on canada melted, but the lands adjusting upwards anyhow

fault scarp

exposed cliff-lake face

sand blows

how to know about evidence about those weird ass new madrid and charleston earthquakes

lahars

viscous mudflows of pyroclastic debris and water

pahoehoe

smooth and ropy lava

aa

blocky and pocky lava

maars

craters (no volcano) from violent eruptions under the surface into groundwater so it explodes

caldera

collapsed magma chamber

trap

word used for the big ass flood plains

columner basalt

when basalt CRACKS into this

landscape inversion

when lava flows into a valley and the surrounding rock erodes leaving the lava around.

Batholith

what is the sierra nevada mountain range

jointing

fractures in bedrock without apparent movement

exfoliation

outer layes peel away releasing confining pressure

inselberg

prominent steep-sided hills of resistant rock rising abruptly

Bornhardt

dome shaped steep sided hills

tors and nubbins

medium scale residual hills

corestones and boulders

smallest type of landform from exhumed intrusive igneous rocks

stone mountain

inselberg in Georgia

talus

the shit that falls at the bottom of a rock cause it missed its fucking mouth

strike

compass direction og rock layer

dip

angle of tilted bed

anticlines

ARCH

syclines

TROUGH

plunging anticline

surface rocks are younger at nose

plunging syncline

surface rocks are older at nose

hogback

greater than 30 degree ridge (the flatirons)

cuesta

asymmetric ridge with gentle dip slope and STEEP cliff

homoclinal ridge

10 degrees to 30 degrees

dome

ridges with cliffs facing center, oldest strata in the middle, youngest in the outside

basin

ridges with cliffs facing outwards, middle is youngest strata, oldest strata on the outside

fault

displacement of rock on one side of fracture with respce to rock on other side

joint

fracture in earth’s crust, but no displacement of rock bodies

hanging wall

block of rocks above fault line

footwall

block of rocks below the fault line

compressional reverse fault

hanging wall moves up, fault plane angle MORE than 45 degrees

compressional thrust fault

hanging wall moves, but the angle is LESS than 45 degrees

tensional normal fault

hanging wall moves down relative to footwall

nevada

place where there is a basin and range ( horsts and valleys)

horst

upfaulted block

graben

downfaulted block

rift valleys

long narrow band of downdropped blocks caused by plated being pulled apart (IE east africa valley system)

east african rift valley

strike slip fault

blocks of crustal rock move laterally