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?