Sediment Flashcards

Sediment Types and Definitions

• Authigenic sediment: Formed directly by precipitation from seawater, categorized as hydrogenous sediment.
• Biogenous sediment: Composed of biological materials; includes calcareous (calcium-based) and siliceous (silicon-based) residues deposited by organisms.
• Calcareous ooze: Comprised mainly of hard remains from organisms that contain calcium carbonate.
• Cosmogenous sediment: Originates from extraterrestrial sources.
• Diatom: Abundant single-celled phytoplankton with silica valves, contributing to biogenous sediments.
• Foraminiferan: Planktonic amoeba-like creatures with calcareous shells that add to biogenous sediment.
• Pteropod: Small planktonic mollusks with calcareous shells, contributing to biogenous sediment.
• Radiolarian: Planktonic organisms with siliceous shells that contribute to biogenous sediments.

Sediment Formation and Composition

• Carbonate Composition Depth (CCD): Depth where calcareous sediment accumulation matches dissolution rate; below this depth, calcium carbonate is scarce.
• Evaporate: Sediment formed by the evaporation of seawater.
• Ooze: Sediment with at least 30% biological material.
• Siliceous ooze: Mainly consists of hard remains of silica-containing organisms.
• Terrigenous sediment: Derived from land and transported to oceans via wind and water.

Sampling and Analysis Techniques

• Clamshell sampler: Device for collecting shallow ocean bottom samples.
• Piston corer: Device designed to penetrate up to 25 meters of sediment, retrieving an intact material plug.
• Well-sorted sediment: Consists of particles that are uniform in size, while poorly sorted sediment includes a variety of sediment sizes.

Sediment Characteristics

• Clay: Sediment with particles smaller than 0.004 millimeters; the smallest size category.
• Silt: Sediment particles ranging from 0.004 to 0.062 millimeters in diameter.
• Sand: Sediment particles that measure between 0.062 and 2 millimeters.
• Nodule: Solid mass formed from hydrogenous sediment, commonly manganese or ferromanganese nodules.
• Oolite sands: Hydrogenous sediment formed by calcium carbonate precipitation from warm seawater.

Geological Studies

• Paleoceanography: Study of historical ocean conditions.
• Stratigraphy: Focuses on defining and analyzing rock strata and their relationships.

Additional Information

• Lithification: The process where sediment is transformed into sedimentary rock through pressure and mineral cement introduction.
• Turbidite: Terrigenous sediment laid down by a turbidity current, characterized by coarse-grained layers mixed with finer sediment.

This quiz covers key concepts related to sediment types, including authigenic and biogenous sediments. Each term is explained with definitions to enhance your understanding of sedimentary processes. Ideal for students studying geology or marine science.