OCE: Exam 1 - Study Guide

Polynesians

The first people to set off on marine expeditions for exploration and migration.

Shipbuilding Advances

Durable ships and navigational instruments like the sextant and compass that aided ocean exploration.

Lapita Culture

Known for using star paths and ocean swells for navigation.

Pre-20th Century Navigation

Mariners navigated using stars, landmarks, and ocean currents.

Major Periods of Ocean Exploration

Ancient, medieval, and modern periods.

Challenger Expedition

The first major scientific oceanographic expedition.

Oceanographic Tools

Sounding lines, sonar, GPS, and satellites used by past and modern oceanographers.

Earth's Spherical Shape

Determined by observing ships disappearing hull-first over the horizon.

Earth's Circumference Calculation

First calculated using shadow angles (Eratosthenes method).

Latitude and Longitude

Latitude is based on Earth's spherical shape; 1 nautical mile = 1 minute of latitude.

Celestial Navigation

Calculating latitude and longitude using sextants before the 20th century.

Unit Conversion

Converting nautical miles to kilometers or meters.

Scientific Method

A process of observation, hypothesis, testing, and conclusion.

Scientific Theory

A well-substantiated explanation of some aspect of the natural world.

Major Events of the Universe

Big Bang (~13.8 billion years ago), formation of Earth (~4.5 billion years ago), origin of life (~3.5 billion years ago).

Nebular Hypothesis

The solar system formed from a cloud of gas and dust.

Solar/Planetary Accretion

The process by which planets form from colliding dust particles.

Density Stratification

Earth's layers formed based on density differences.

Earth's Layers

Continental Crust, Oceanic Crust, Mantle, Outer core, Inner Core, with density increasing towards the core.

Ocean Water and Salt Sources

Originated from volcanic outgassing and comet impacts.

Earth's Past Atmospheres

Primordial (hydrogen and helium), secondary (volcanic gases), current (oxygen-rich).

Theories of Life Evolution

Include primordial soup and hydrothermal vent hypotheses.

First Life Organism

Likely simple prokaryotes.

Major Events of Life

Evolution of multicellular organisms, Cambrian explosion, vertebrates, mammals, humans.

Rock or Fossil Age Determination

Through radiometric dating and relative dating.

Wegner's Evidence for Continental Drift

Fossil distribution, rock formations, and the fit of the continents.

Hess' Seafloor Spreading Evidence

Mid-ocean ridges and symmetrical magnetic stripes on the ocean floor.

Plate Tectonic Theory

Earth's crust is divided into plates that move due to mantle convection.

Earth's Magnetic Field

Magnetic poles reverse over time, recorded in rocks, used to reconstruct past continental positions.

Magnetic Anomaly and Age Patterns

Symmetrical patterns of magnetic stripes on either side of mid-ocean ridges correspond to seafloor age.

Types of Plate Boundaries

Divergent (mid-ocean ridges), convergent (trenches), transform (faults).

Famous Plate Boundary Examples

San Andreas Fault (transform), Himalayas (convergent), Mid-Atlantic Ridge (divergent).

Hot Spot

A volcanic region fed by underlying mantle plumes, like Hawaii.

Spreading Rate Calculation

Rate = Distance / Time.

Earthquake and Volcano Locations

Common at convergent and divergent boundaries.

Continental Movement

Pangaea formed and broke apart over the past 600 million years.

Ocean Depth Measurement Tools

Echo sounders, sonar, satellite altimetry.

Hypsographic Curve

A graph showing the distribution of Earth's surface elevation and ocean depth.

Passive vs active

Passive margins are broad and shallow; active margins are narrow and tectonically active.

Slope Calculation

Slope = Rise/Run or Depth/Distance.

Ocean Basin Features

Continental shelves, slopes, rises, abyssal plains, mid-ocean ridges formed by erosion, sedimentation, and tectonic activity.

Organisms on the Seafloor

Corals, deep-sea fish, tube worms.

Ocean Basin Cross-Section Features

Includes continental shelf, slope, rise, abyssal plain, mid-ocean ridge.

Mid-Ocean Ridge Features

Hydrothermal vents and rift valleys.

Mid-Ocean Ridge vs rises

Ridges are steep and slow-spreading; rises are flatter and fast-spreading.

Deep-Water Coral Ecosystems

Slow-growing corals adapted to cold, dark environments.

Sediment Collection Methods

Dred