Geo 2400 Exam 1

Uniformitarianism

The principle that the present is the key to the past, and the past is the key to the future. Events that happen today also happened in the past.

Catastrophism

Idea that landscapes are mostly shaped by major catastrophic events.

Constructional processes

Geological processes that create new landforms and add material

Erosional processes

Geological processes that remove material and destroy landforms

Endogenic processes

Processes driven by internal forces deep within the earth with internal heat and radioactive decay.

constructive

Endogenic processes are constructive/erosional?

Exogenic processes

Processes that operate at/near the earth’s surface and are driven by external energy such as solar energy and gravity.

erosional

Exogenic processes are constructive/erosional?

The sun

Major source of energy in the geomorphic system

Insolation

Solar energy is also called…

30

___% of incoming solar energy is directly reflected

rotational

source of energy: earth’s forces responsible for the coriolis effect

gravity

source of energy: attraction of one object to another

tides

source of energy: involved the moon and sun

geothermal

source of energy: heat generated by radioactive decay

orogenic

source of energy: work against gravity to build mountains

meter

Si unit for length

kilogram

Si unit for mass

second

Si unit for time

mass x acceleration

Force equals…

Newtons

Force is measured in …..

Weight

Force of gravity acting on mass is known as _____

mass times gravity

Weight equals …..

Work

When a force moves an object a distance, this is known as …..

Joules

Work is measured in _____

force times distance

Work equals …..

Energy

The capacity to do work

9.81 m/s²

acceleration due to gravity amount

mass times gravity times height

potential energy formula

(1/2)mv²

kinetic energy formula

Power

rate at which work is done

work/time

Power equals …..

F/v

another formula for Power

Watts

Power is measured in _____

1 Joule/second

1 watt is also equal to …..

746 Watts

1 horsepower equals ….

4.18 Joules

1 calorie equals …..

cause and effect

the rational approach to geomorphology mostly involves looking at ________

field studying

stadia rod, hand level, and compass are common tools used during _____________

optical surveying

field surveying methos done with an auto level, alidade, and transit. Gives a precise measurement but is bulky.

passive

Type of satellite imagery that involves noting what is already visible/present

active

Type of satellite imagery where an instrument shoots out a laser/light/sound and measures the response

laser ranging

fieldwork observation method that sends a laser to a reflector and measures travel time to calculate distance

drones

observation method where a hovering device collects overlapping images and used Structure from Motion software to create a 3d model

GPS

system where a reciever determines exact position using at least 4 satellite signals

remote sensing

the act of collecting information without directly touching or measuring anything

radar

a system that uses radio waves to find and track distant objects, can map large areas and technology using sonar can map the ocean floor

SAR/synthetic aperture radar

sends radar pulses and measures return, used for very large areas.

inSAR

comparing radar images taken at different times to detect changes

Lidar

light detection and ranging, using laser pulses to measure earth’s surface.

roughness

radar can also measure surface ________

dark

smooth surface=less reflection=area appears _____

bright

rough surface=more reflection=surface appears ______

landsat

first launched in 1972, provided a global collection of multispectral imagery

DEM/digital elevation map

map where each pixel/block represents a different elevation

GIS

computer based system to store, analyze, and display geographic data

relative dating

dating methos that determines older vs younger rather than a specific age of materials

superposition

law of ________ states that in a horizontal bed, the top layer is the youngest

cross-cutting relationships

law of ____________ states that a feature cutting through another is younger

absolute dating

dating method where age values are found/estimated

calibrated relative dating

relative dating method where an object with a known age is used to get an estimate of another object

lichenometry

using mosses and lichen growth to estimate age

amino acid racemization

dating method used when shell/bone is preserved

dendrochronology

using tree rings to determine age

radiocarbon dating

using carbon14 to determine age of once-living material

5730 years

carbon14 half life

calibration

radio carbon dating requires ______ because a radio carbon year does not equal our calendar year

50,000

radio carbon dating is only accurate for about _____ years into the past

potassium-argon dating

absolute dating method useful for volcanic rocks

uranium-thorium dating

absolute dating method useful for calcium carbonate deposits, limestone caves, and coral reefs

uranium-thorium

which absolute dating method takes a long time and is only useful for very large time periods?

quaternary

period from today to about 2.58 million years ago

luminescence dating

absolute dating method useful when there’s no organic matter. Determines when a mineral was last exposed to light/heat.

cosmogenic nuclide dating

absolute dating method that dates the time of burial by noting presence of cosmogenic nuclides, special isotopes produced when cosmic rays interact with earth’s surface

integration time

period over which a measured rate is averaged

sediment generation

rate at which sediment is produced and eroded from parent material

sediment yield

rate at which sediment actually leaves a landscape/drainage area

Q

variable that represents discharge, amount per unit time

Cesium 137

Isotope useful for studying erosion/deposition over decades from nuclear weapons testing

30.1 years

half life of Cesium 137

thermochemistry

using temperature-dependent processes in minerals to reconstruct the history of rock cooling and exhumation (using isotopes and fission tracks)

Suess effect

effect which shows a decrease in atmospheric carbon 14 as a result of burning fossil fuels. Co2 dilutes c14

open system

system in which there is free exchange with surroundings

closed system

system where there is little/no energy exchange with surroundings

geomorphic threshold

critical condition when a system changes state

field

applying water, grain-size analysis, placing sensors, and pebble count are examples of ____ techniques for geomorphology experiments

lab

using a flume, and artificial stream, is an example of a ___ technique for geomorphology experiments

proxy record

indirect evidence of age such as tree rings, corals, and ice cores.

regolith and organic matter

to a geoscientist, soil is defined as vertically layered residue of ___________________

addition

soil development process that includes adding organic matter, dust, bedrock, or sediment

loss

soil development process that removes material through erosion or dissolution

translocation

soil development process which is the movement of material from one part of the soil profile to another

leaching

dissolved material leaving the soil through water

colloid

small soil particle that can be picked up and redeposited by water

eluviation

process of transporting clays an mobile ions out of a layer of soil

illuviation

washing of material into a layer of soil

residual

______ soils form in place from weathered parent material

colluvial

______ soils move downslope and are well turbated

cumulic

_______ soils accumulate slowly out of dust or ash

Climate

soil forming factor that is mostly concerned with temperature and precipitation