Marine Provinces

Question 1

Echo sounders

Answer 1

Device that sends a sound signal (called a long) into the ocean to produce echoes when the sound bounces off any density difference, such as marine organisms or the ocean floor

Question 2

Precision depth recorder (PDR)

Answer 2

Uses a focused high frequency sound beam to measure depths to a resolution of about 1 meter

Question 3

Sonar

Answer 3

Acronym for sound navigation and ranging

Question 4

SeaBeam

Answer 4

First multibeam echo sounder-made it possible for a survey ship to map the features of ocean floor along a strip up 60km

Question 5

Sea MARC and GLORIA

Answer 5

Side scan sonar systems that can be towed behind a survey ship to produce a strip map of ocean floor bathymetry

Question 6

Seismic reflection profiles

Answer 6

Low frequency sounds produced by explosions or air guns which penetrate beneath seafloor and reflect off boundaries between different rock or sediment layers

Used for mineral and petroleum exploration

Question 7

Hypsographic curve

Answer 7

Shows the relationship between the height of the land and the depth of the oceans

Question 8

Continental margins

Answer 8

Shallow water areas close to continents

Question 9

Deep-ocean basins

Answer 9

Deep water areas farther from land

Question 10

Mid-ocean ridge

Answer 10

Shallower areas near the middle of an ocean

Question 11

Passive continental margin

Answer 11

Imbedded within the interior of lithospheric plates and are therefore not in close proximity to any plate boundary. Therefore they usually lack major tectonic activity

Question 12

Active continental margins

Answer 12

Associated with lithospheric plate boundaries and are marked by a high degree of tectonic activity.
Two type: convergent and transform

Question 13

Convergent active margins

Answer 13

Associated with oceanic-continental convergent plate boundaries.

Question 14

Transform active margins

Answer 14

Less common and associated with transform plate boundaries

Question 15

Continental shelf

Answer 15

A generally flat zone extending from the shore beneath the ocean surface to a point at which a marked increase in slope angle occurs (shelf break)

Question 16

Shelf break

Answer 16

A point at which a marked increase in slope angle occurs

Question 17

Continental slope

Answer 17

Lies beyond the shelf break

Where deep-ocean basins begin

Question 18

Submarine canyons

Answer 18

The continental slope exhibit submarine canyons
V-shaped in profile view and have branches or tributaries with steep to overhanging walls
Resemble canyons formed on land that are carved by rivers and can be quite large

Question 19

Turbidity currents

Answer 19

Underwater avalanches of muddy water mixed with rocks and other debris

Question 20

Continental rise

Answer 20

A transition zone between the continental margin and the deep ocean floor comprised of a huge submerged pile of debris

Question 21

Graded bedding

Answer 21

Slowing turbidity currents causing suspended material to settle out in a distinctive type of layering. Grades in size upward.

Question 22

Turbidite deposits

Answer 22

Stacks of graded bedding that compose continental rise

Question 23

Deep sea fans

Submarine fans

Answer 23

Deposits at the mouths of submarine canyons that are fan shaped
Create continental rise when they merge together along base of continental slope

Question 24

Bathymetry

Answer 24

The measurement of ocean depths and the charting of the shape or topography the ocean floor

Question 25

Abyssal plains

Answer 25

Extending from the base of the continental rise into the deep ocean basins are flat depositional surfaces with slopes that average a small fraction of a degree and cover extensive portions of the Deep ocean basins

Question 26

Suspension settling

Answer 26

Where fine particles accumulate on the ocean floor

Question 27

Abyssal hills (or seaknolls)

Answer 27

Volcanic features on ocean floor that are less than 100m tall

Question 28

Continental flood basalts

Answer 28

Volcanic accumulations (igneous provinces) found in continents

Question 29

Ocean trench

Answer 29

Deep linear scars in the ocean floor, caused by collision of two plates along convergent plate margins

Question 30

Volcanic arc

Answer 30

The landward side of the trench that may produce islands (islands of Japan-island arc) or volcanic mountain range along margin of a continent (Andes-continental arc)

Question 31

Back arc spreading center

Answer 31

When an overriding plate gets pulled toward the trench, producing a spreading center behind (landward of) the volcanic arc

Question 32

Rift Valley

Answer 32

A central downdropped valley along the crest of a mid ocean ridge that is entirely volcanic

Question 33

Pillow basalts

Answer 33

Smooth rounded lobes of rock that resemble a stack of bed pillows created when hot basaltic lava spills into seafloor and is exposed to cold seawater that chills the margins of the lava.

Question 34

Ocean ridges

Answer 34

Segments of mid-ocean ridge

Have prominent Rift Valley and steep, rugged slopes

Question 35

Oceanic rises

Answer 35

Slopes that are gentler and less rugged