ERTH20 Final Exam

Transform Boundary

Sliding past; San Andreas Fault, Alpine Fault.

Convergent Boundary

Colliding; mountains, volcanoes, trenches.

Southern California Plate Boundary

Transform boundary; Pacific Plate & San Andreas Fault.

Principle of Original Horizontality

Sedimentary rocks are originally deposited in horizontal layers.

Principle of Cross-Cutting Relationships

Faults & intrusions are younger than the rocks they cut.

Principle of Inclusions

Inclusions are older rock fragments inside younger rock.

Types of Unconformities

Disconformity, angular unconformity, nonconformity.

Radiometric Dating Formula

Age = (number of half-lives) × (half-life).

Parent Isotope

Decaying isotope.

Daughter Isotope

Product of radioactive decay.

Half-Life

Time for half of the isotope to decay.

Seawater Chemistry Equipment

Cylinder, test tubes, freshwater, saline, hot water, cold water.

Density Observation

Cold water = higher density; hot water floats, cold water sinks.

Saltwater Mixing & Density

More salt = higher density due to added mass.

Western Boundary Currents

Warm & fast currents (e.g., Gulf Stream, Brazil Current).

Eastern Boundary Currents

Cold & slow currents (e.g., California Current, Peru Current).

Northern Hemisphere Gyres

Rotate clockwise.

Southern Hemisphere Gyres

Rotate counterclockwise.

Southern California Currents

California Current flows southward.

El Niño conditions occur when?

Every 2–10 years, lasting 12–18 months.

El Niño Conditions

Pressure shifts result in weaker or reversed Tradewinds.

La Niña Conditions

Opposite of ENSO; strong Tradewinds and equatorial currents.

Wave Base Formula

L/2.

Depth of Breaking Waves

L/20.

Height of Breaking Wave

3/4 of wave height.

Wave Velocity Formula

C = L/T.

Shallow Water Waves

Occur where depth < wave base.

Deep Water Waves

Occur where depth > wave base.

Semidiurnal Tide

Two highs & two lows of equal height daily.

Mixed Semidiurnal Tide

Highs & lows differ in height.

Diurnal Tide

One high and one low per day.

Spring Tide

Sun + Moon reinforce tides → higher highs & lower lows.

Neap Tide

Sun & Moon at right angles → reduced tides.

Beach Drift

Zig-zag movement of sediment along the beach.

Longshore Currents

Waves hit at an angle → water & sediment move parallel to shore.

Direction of Longshore Drift

Determined by angle of incoming waves.

Sediment & Man-Made Structures

Structures block natural longshore transport causing erosion/deposition.

Erosional Coastline

High wave energy & fast longshore currents.

Depositional Coastline

Low wave energy & slow longshore currents.

Emergent Coasts

Features above sea level (marine terraces).

Submergent Coasts

Features below sea level (estuaries, drowned dunes).

Down current of spits

The end of the hook is the downcurrent.

Sediment deposits

The upcurrent side of groins & jetties.

Atmospheric Heating Radiation

Sunlight heats Earth.

Atmospheric Heating Process

Visible light warms Earth; Earth emits IR; IR absorbed by water vapor.

Composition of gases

Nitrogen and Oxygen.

Stratosphere

Ozone is trapped and builds up, making the temperature increase.

Average pressure of altitude

1013.

Earth's seasons

Angle of sunlight caused by Earth's axial tilt.

Adiabatic temperature

Rising air cools (pressure decreases); sinking air warms (pressure increases).

Cloud Cover Effect

Clouds reflect sunlight & trap infrared heat.

Vertical Air Temperature Change

Rising air cools; sinking air warms.

Reason Air Changes Temperature

Expansion cools rising air; compression warms sinking air.

Stratosphere vs Troposphere

Stratosphere warms with height; troposphere cools with height.

Lapse Rate Interpretation

Descending air compresses & warms.

Water Vapor Diagram Rule

Higher temperature → more water vapor capacity.

Highest salinity

In subtropical zone.

Frontal wedging

A clash of two air masses coming together; severe weather.

Orographic lifting

When mountain ranges get in the way of flowing air.

Convective lifting

Due to heating, air is rising.

Equinox Latitude & Dates

0°; March 20–21 & Sept 22–23.

Solstice Latitude & Dates

23.5°; June 20–22 & Dec 21–22.

Heat Capacity Results

Fastest heating = dry sand; slowest = water.

Warm Land Pressure

Low pressure.

Cool Land Pressure

High pressure.

Warm Water Pressure

Low pressure.

Cool Water Pressure

High pressure.

Sea Breeze

Cooler sea → wind blows from sea to land.

Land Breeze

Cooler land → wind blows from land to sea.

Summer Monsoon

Land heats up faster → moist air from ocean produces rain.

Winter Monsoon

Land cools quickly → dry air flows offshore.

Orographic Lifting

Air rises over mountains → cools & condenses.

Anticyclone

High pressure, sinking air, clear skies.

Cyclone

Low pressure, rising air, cloudy/stormy skies.

Cold Front

Heavy rain/thunderstorms; cold air wedges under warm air.

Warm Front

Warm temps; warm air glides over cold air.

Fast Winds on Maps

Closely spaced isobars.

Slow Winds on Maps

Widely spaced isobars.

Global Pressure Zones

Polar highs, subpolar lows, subtropical highs, equatorial lows.

Global Wind Belts

Tradewinds, Westerlies, Polar Easterlies.

Santa Ana Wind Location

Tight isobars, no fronts, coastal low pressure.

Thunderstorm Map Location

Cold front + low pressure + tight isobars.

Bermuda high

High pressure zone in North Atlantic.

Hurricane Map Location

Warm ocean water + tight isobars + low pressure center.

Hurricane Movement Direction

Glacial Period

Cold ice-age conditions.

Interglacial Period

Warm periods between glacials.

Greenhouse Gas Effect

More greenhouse gases → warmer temperatures.

CO₂-Temperature Relationship

If CO₂ rises, temperature rises.

Modern Greenhouse Trends

CO₂ & methane have risen since the 1800s.

Recent Ocean Temperature Trends

Oceans warming; sea level rising.

High Latitude Temperature Trend

High latitudes warming faster than global average.

CO₂ & Ocean pH

CO₂ dissolves in seawater → lowers pH (ocean acidification).