Marine bio test

Bathymetry

Multi-beam sonar (sounds to bottom of ocean)

-The depth, shape, and structure of the seafloor

Continental Shelf

a portion of a continent that is submerged under an area of relatively shallow water known as a shelf sea

Continental slope

the slope between the outer edge of the continental shelf and the deep ocean floor.

Continental Rise

the gently sloping accumulation of sediment at the bottom of the continental slope.

Canyons

-Made from erosion over time

-sea level can erode crust to form a canyon

abyssal plain

very level area of the deep-ocean floor, usually lying at the foot of the continental rise

reefs

-not always coral

-Form when coral larvae attach to rocks in the water/hard things along edges of islands

Mid-ocean ridges

-Underwater mountain range or ridgeline

-formed along divergent plate boundaries

Seamounts

An underwater mountain rising from the ocean floor and having a peaked or flat-topped summit that hasnt reached the surface yet

trenches

a long, narrow depressions on the seafloor

-always at least 1 oceanic plate subducting under a continental or oceanic plate

island

-almost always made from volcanic activity

-may still have active volcanoes

SONAR

-Sound navigation and ranging

-Side scan sonar=directs nonar waves at an angle

LiDAR

Light Detection and Ranging

uses lasers

submersibles

-deep diving submersible

SCUBA

self-contained underwater breathing apparatus

why do we have an ocean?

-from comets that had water rocks on them

-water vapor in atmosphere condenses into liquid rain and forms ocean

layers of the earth

crust, mantle, outer core (liquid), inner core

tectonic plates

Sections of the Earth's crust that move due to convection currents.

convection in the mantle

the movement of rock within the mantle where hot rock rises and cooler rock sinks

continental crust

The portion of the earth's crust that primarily contains granite, is less dense than oceanic crust,

-silica-rich

oceanic crust

-thin and rigid

-basalt and gabbro rock

-high density

plate boundaries

Earth's crust is broken (fault) and rocks slip past each other in one of 3 types of plate boundaries.

-results in mountains, volcanos, earthquakes

convergent plate boundary

where two plates collide, come together, or crash into each other.

subduction zone

The region where oceanic plates sink down into the asthenosphere.

-subducts under one another

ring of fire

A major belt of volcanoes that rims the Pacific Ocean

marinara trench

-in south pacific (between Australia and Japan)

-43 miles wide

-1,500 miles long

-36,000 feet deep

divergent plate boundary

an area beneath the ocean where tectonic plates move away from each other

continental rift

A linear belt along which continental lithosphere stretches and pulls apart

Oceanic rift: Mid-oceanic ridge (sites of seafloor spreading)

-seafloor spreading, magma oozes up through cracks in rift zones creating new lithospheric crusts

-most are unmapped

plate tectonic theory

the theory that the lithosphere is broken up into large plates that move and then rejoin

continental Drift hypothesis

The idea that continents have moved and are still moving slowly across the Earth's surface.

Marie Tharp

A geologist and an oceanographer who mapped the ocean floor and proved plate tectonics