Unit 3- marine provinces and marine sediments

Most abundant features-

Abyssal hills or sea knolls

Passive margins have well developed-

Abyssal plains

Convergent active margins rarely have-

Abyssal plains bc the trenches act as gutters that trap sediment moved by turbidity currents

Greatest quantity of lithogenous sediment is found-

Around the margins of the continents where it is constantly moved by high energy currents along the shoreline and in deeper turbidity currents

Active margins-

Associated with lithospheric plate boundaries and have all of tectonic activity

Ocean floor can be divided into what 3 provinces

Continental margins, deep-ocean basins, and mid-ocean ridges

Types of active margins-

Convergent and transform

Passive margins-

Embedded within the interior of lithospheric plates, aren't close to any plate boundary. Lack tectonic activity

Abyssal Plains formed by

Fine particles of sediment slowly drifting onto the deep-ocean floor. Over millions of years a thick blanket of sediment is produced by suspension settling.

Continental shelf-

Flat zone extending from the shore to the shelf break

Pelagic deposits-

Found in deep-ocean basins; fine grained

Neritic deposits-

Found on continental shelves and shallow water near Islands; coarse grained

Continental borderland-

Land marked by a high degree of relief (islands, shallow banks, deep basins)

Continental slope-

Lies beyond shelf break, where the deep ocean basins begin

Bathymetry-

Measurement of ocean depths and the charting of its shape(topography)

Submarine canyons-

Narrow, deep,v-shaped valleys

The pacific ring of fire-

Occurs along the margin of the Pacific Ocean, has the majority of the earths active volcanoes and earthquakes bc of the prevalence of the convergent plates boundaries along the pacific rim

Smooth, rounded lobes of rock that resemble a stack of pillows

Pillow lavas

Majority of lithogenous sediment is composed of-

Quartz (SiO2)

Hypsographic curves show-

Relationship between the height of the land and the depth of the ocean

Hydrothermal vents-

Sea floor hot springs created when cold water seeps along cracks and fractures in the ocean crust and approaches underground magma chamber

The type of soundings we hardly use is-

Seismic reflection

Continental margins-

Shallow water areas close to continents

Mid-ocean ridges-

Shallower water area near the middle of an ocean

Graded bedding-

Suspended material settles in a distinctive type of layering. Large pieces first that get progressively smaller

How are submarine canyons formed-

Turbidity currents and mass wasting (slump,slides, debris flow)

Turbidity currents-

Underwater avalanches or muddy water mixed with rocks, etc.

Types of vents-

Warm water, white smokers, black smokers

White smoker-

Water temp 30 to 350 and emit water that is white bc of light colored compounds, like barium sulfide

Black smoker-

Water temp above 350 and emit black water bc of dark colored metal sulfides like iron, nickel ,copper and zinc

Warm-water vents-

Water temp below 30 and generally emit clear water

Pillow lavas/pillow basalts occur-

When hot basaltic lava spills into the sea floor and exposed to cold seawater that chills the margins of the lava

Deep-ocean basins-

Deep water areas farther from land

Deep-sea fans/ submarine fans-

Deposits at the mouths of submarine canyons. Creates the continental rise when they merge

Lithogenous sediment-

Derived from pre existing rock material that originates on the continents or islands from erosion, volcanic emotions or blown dust

Continental rise-

Transition zone between the continental margin and the deep-ocean floor made of huge pile of debris