EARTH SCIENCE LAB STUDY GUIDE

Aerial photographs

important tools for studying earth's surface

stereogram

Overlapping images that allow you to see the earth's surface in 3D

Satellites

are used to study phenomena such as volcanic eruptions, hurricanes, and oil spills

satellites

help identify hidden features on earth's surface and in remote locations

topographic map

is a two dimensional flat representation of a three dimensional land surface

topographic maps show

-hills, valleys, streams, lakes, rivers, slopes, gullies, mountains
-elevations and depressions of hills and mountains
roads, buildings, parks

Quadrangle

is a rectangular section of the Earth’s surface that is bound by lines of latitude at the top/bottom and lines of longitude along the sides

Latitude

north / south

longitude

east / west

Prime meridian

GREENWICH, ENGLAND

Contour lines have

equal lines of elevation

Relief is

the difference in elevation between landforms (difference between the highest point and lowest point on the map)

Gradient is

the measurement of the steepness of a slope (finding the steepness of an incline or decline)
-Amount of rise or fall of points a and B divided by the
distance between points A and B

A topographic profile

is a cross section that shows the elevation and slopes along a given line

Vertical exaggeration

is larger than the horizontal scale of the map
-Divide the horizontal ratio scale by the vertical ratio scale

Valley

low lying land bordered by higher ground

hill

rounded elevation of land- a mound

ridge

linear or elongated elevation or crest of land

closed depression

low point/area in a landscape from which surface water cannot drain, contour lines with hachure marks

steep slope

closely spaced contour lines

gentle slope

widely spaced contour lines

PLSS

public land service system

GPS

global positioning satellite

UTM

Universal Transverse Mercator grid

Agents of Earth

water, wind, glacier, creatures

water cycle

Precipitation, evaporation, transpiration, runoff, infiltration

Infiltration

rain that falls on the ground and is absorbed, runoff happens when there is no more room for absorption

Rivers and streams

are responsible for creating erosion and deposition

An example of a stream valley

GRAND CANYON

Ground water fully soaks the soil in the

zone of saturation

Water table

Upper surface of the saturated zone

The unsaturated zone has pores that are mainly filled

AIR

Ground subsidence

is when ground water is removes and sediments and grains become compressed and the pores collapse so the land surface cracks and sinks

desert

arid

steepe

semiarid

desert covers ___% of earths surface

30%

alluvial fans

form as streams deposit sediments at a base of a mountain

playa lake

temporary feature that evaporates or infiltrates the ground in the center of a basin

bajadas

union of alluvial fans

playa

dry, flat lake bed

pediment

broad sloping bedrock surface, covered by thin layer of sediment

inselburg

continued erosion, leaving nearly flat surface dotted with isolated peaks

Sand dunes ripple because

of wind

Glacier forms

when yearly snow falls exceeds quantity of ice lost by melting

Valley and alpine glaciers form

on mountains and flow down through valleys

Ice sheet

is larger than a glacier and flows in all directions

GREENLAND

NORTHERN HEMISPHERE

ANTARCTICA

SOUTHERN HEMISPHERE

cirque

is a amphitheater shaped basin at the head of a glaciated valley

arete

is a narrow knifelife ridge that separates two adjacent glaciated valleys

horn

is a pyramid like peak

hanging valley

U shaped valley

Glacial drift

all glacial sediments

Till

is unsorted sediments deposited directly by a glacier

Moraines

are layers of till that form on outer margins of glaciers

Stratified drift

is sorted and deposited by glacial meltwater

drumlin

looks like an inverted spoon

kettle lake

lake depressions formed when blocks of ice become lodged in ground

eskers

are sinuous ridges made of sand/gravel deposited from meltwater near glacier terminus

tarn

is a small lake occupying a cirque

Paternoster lakes

is a chain of small lakes that occupy basins formed by glacial erosion

radioactive isotopes

-is used to calculate the ages of rocks
-emit particles from their nuclei that cause radiation
-The rate of decay is the half-life, the time it takes for half of the parent isotope to decay

Original horizontality

bedding originally deposited in horizontal sheets

lateral continuity

beds extend laterally out in all directions until pinched out by reaching edge of deposition basin

superposition

is the oldest layers at the bottom of sequence, youngest layers at the top

Inclusions

are a clast included in another rock must be older than the rock it is in

Cross cutting

is any feature that cuts through a body of rock is younger than the rock

conformable beds

Layers of rock that have been deposited without interruption

unconformity

represents a long period of time where no deposition occurred

Angular unconformity

is when adjacent beds are at an angle

disconformity

is a gap in rock record representing a period of erosion rather that deposition

Nonconformity

is younger sedimentary rocks overlying older metamorphic or igneous rocks

Fossils

are important tools for determining geological history and prehistoric environments

PETRIFICATION

internal pores/caveties of an organism are filled with precipitated mineral matter

CAST

the space once occupied by dissolved shell or other structure is filled with mineral matter

IMPRESSION

a replica of an organism left in fine-grain sedimentary rock

Carbonization

preservation that occurs when fine sediments encase a delicate plant or animal forms and leaves a residue of carbon

Amber

hardened resin of ancient trees that preserved delicate organisms such as insects

indirect evidence

traces of prehistoric life but not the organism itself

oceanography

Study of the physical and biological aspects of the ocean
-Ocean covers 71% of earth’s surface

Ocean Basins:

Pacific
Atlantic
Arctic
Indian
Southern

ocean basins form

where two tectonic plates diverge from one another

Continental shelf

flooded extension of continent, submerged surface that extend from the shoreline toward the ocean basin

Continental slope

the seaward edge of the continental shelf; a relatively steep zone that marks the boundary of continental crust and oceanic crust

Seamounts

are remnants of extinct volcanic activity

Bathymetry

mapping the ocean floor using sonar

Physical properties of the ocean

Salinity- amt of dissolved salts in water
Temperature
Density of seawater is influenced by salinity and temperature
Surface currents are primarily driven by prevailing global winds
Deep ocean currents are primarily driven by a gradient in water density
WHERE DO SURFICIAL WATERS SINK?

waves

is vibratory motion of water particles around their mean positions

currents

are unidirectional movement of a body of water

tides

are regular fluctuations in local sea levels which occur as a result of the moon’s gravitational pull on the Earth

Waves transfer energy from

one place in the ocean to another; most ocean waves derive energy from wind

Wave height

vertical distance between trough and crest

wavelength

horizontal distance between two crests

crest

water particles are at their highest point

trough

water particles at their lowest point

waves are ______ as they approach shoreline

refracted

Deposited sediments

accumulate to form beaches, spits,a nd baymouth bars

Breach drift

occurs when an uprush of water an angle to the shoreline causes sediments to move in a zigzag pattern along the beach

Longshore current

occurs when turbulent water in the surfzone moves in a zigzag motion, parallel to shore

Two coasts

US PACIFIC and US ATLANTIC