Oceanography Chapter 5

Paleoceanography

the study of the oceans past

piston corer

A seabed-sampling device capable of punching through up to 25 meters of sediment and returning an intact plug of material

Hydrogenous Sediments

A sediment formed directly by precipitation from seawater

Well- sorted sediments

A sediment in which particles are of uniform size

Poorly-sorted sediments

A sediment in which particles of many sizes are formed

Cosmogenous Sediments

Sediment of extraterrestrial orgin

Pelagic Sediments

Sediments of the slope, rise and deep-ocean floor that originate in the ocean

Biogenous Sediment

Sediment of biological orgins

clamshell sampler

A sampling device used to take shallow samples of the ocean bottom

Turbidities

A terrigenous sediment deposited by a turbidity current' typically, coarse-grained layers of nearhsore origin interleaved with finer sediment

higher

Biological Productivity is _____ farther from land

Neritic Sediments

Continental shelf sediment consisting primarily of terrigenous material

Lithification

Conversion of sediment into sedimentary rock by pressure or by the introduction of a mineral cement

Evaporites

Deposits formed by the evaporation of ocean water or from landlocked seas or lakes

brought by rivers and dissolved in the ocean at oceanic ridges

How are biogenous sediments transported

Turbulent Flow

How are coarser sediments transported?

Streams Waves and Currents

How are smaller particles transported?

Through river runoff

How are these sediments transported to the ocean?

Oolite Sand

Hydrogenous sediment formed when calcium carbonate precipitates from warmed seawater as pH rises, forming rounded grains around a shell fragment or other particle

Calcareous Ooze

Ooze composed mostly of the hard remains of organisms containing calcium carbonate

Siliceous Ooze

Ooze composed mostly of the hard remains of silica-containing organisms

Sediment

Particles of organic or inorganic matter that accumulate in a loose, unconsolidated form.

Terrigenous Sediments

Sediment derived from the land and transported to the ocean by wind and flowing water

Ooze

Sediment of at least 30% biological origin

Stratigraphy

The branch of geology that deals with the definition and description of natural divisions of rocks; specifically, the analysis of relationships of rock strata.

Calcium Carbonate Compensation Depth

The point of depth where calcareous oozes no longer form

Microtekites

Translucent oblong particles of glass, a component of cosmogenous sediment

Quartz sand, clays, estuarine mud

What are 3 examples of terrigenous sediment?

Beach sands, muds of bays, mix of silt and tiny shells on continental margins, clay on deep ocean floor, oozes of abyssal plains and nodules and coatings

What are some examples of sediment

manganese nodules

What are the most famous type of hydrogenous sediments Solid mass of hydrogenous sediment

Interplanetary dust and rare impacts by large asteroids and comets.

What are the two main sources of cosmogenous sediments?

foraminifera an coccolithophores

What are two examples of calcareous oozes

radiolarian and diatoms

What are two examples of siliceous oozes

Terrigenous

What kind of sediments are neritic sediments?

Terrigenous and Biogenous

What two types of sediments make up most of the marine sediments in the ocean?

the top of Mount Everest

What's an example of a mountain that has marine limestone

where there is high biological productivity, such as continental margins and areas of upwelling

Where are biogenous sediments usually found

Gulf of California The Red Sea and the Persian Gulf

Where are evaporites forming today? (3 examples)

Continental margins, abyssal plains, polar ocean floors

Where is Terrigenous sediment found?

Pelagic Deposits

Which kind of deposits has a greater porportion of biogenous material

usually slowly, but can accumulate quickly (Ex: in a drying lake)

how fast do hydrogenous sediments collect?