Sediments and Sedimentary Rocks

These flashcards cover key vocabulary and concepts related to sediments and sedimentary rocks, including definitions, processes, and types of sediments.

Sediment

Unconsolidated matter transported by surficial processes and deposited on the Earth's surface.

Sedimentary Rock

Rock formed from the lithification of sediment through compaction and cementation.

Lithification

The process of converting sediment into rock through compaction and cementation.

Clastic Sediment

Sediments composed of particles that are physically deposited by agents like water, wind, or ice.

Chemical Sediment

Sediment formed from the precipitation of minerals from supersaturated solutions.

Biogenic Sediment

Sediment formed from organic materials, such as shells of organisms.

Sorting

The segregation of sediment by size due to variations in current velocity.

Roundness

A measure of how smooth and rounded the edges of sediment grains are due to transport.

Compaction

The process whereby sediment grains are pressed together, reducing pore spaces.

Cementation

The process where minerals precipitate from solution and fill spaces between sediment grains.

Ripple Marks

Sedimentary structures formed by the action of water or wind on sediment.

Fossils

Remains or traces of ancient life preserved in sedimentary rocks.

Sedimentary Facies

Distinct units of sedimentary rock that reflect different depositional environments.

Diagenesis

The physical and chemical changes occurring in sediments after sedimentation.

Maturation

The process whereby organic matter transforms into oil or gas due to heat and pressure.

Aquifer

A geological formation that can store and transmit water natural reservoirs.

Evaporite

Minerals formed by the evaporation of water, leaving behind solid deposits.

Limestone

A sedimentary rock primarily composed of calcite, often formed from biological activity.

Chert

A hard, compact sedimentary rock composed primarily of silica.

Iron Formations

Sedimentary rocks rich in iron minerals, often formed in ancient oceans.

Halite

A type of evaporite mineral commonly known as rock salt (NaCl).

Banded Iron Formation (BIF)

Sedimentary rocks consisting of alternating layers of iron-rich minerals and silica.

Photosynthesis

The process by which green plants and some organisms use sunlight to synthesize foods with CO2 and water.

Diatom

A microscopic algae with silica shells, contributing to siliceous sediments.

Foraminifera

Single-celled organisms with calcium carbonate shells, important in biological sediments.

Stromatolites

Layered bio-chemical accretions formed by the activity of microorganisms, especially cyanobacteria.

Sedimentary Structures

Features that develop during sediment deposition including layers, ripple marks, and cross-beds.

Granularity

The size of mineral or rock particles in sedimentary rocks.

Supersaturation

A condition in which a solution contains more dissolved material than it can normally hold.

Porosity

The ratio of void spaces in a material, crucial for understanding rock permeability.

Carbonate Platforms

Large, shallow marine areas where carbonates are deposited and often form reefs.

Coccolithophore

A type of microscopic algae that produces calcium carbonate plates, contributing to carbonate sediments.

Transportation

The process through which eroded material is moved from one location to another by natural forces.

Deposition

The accumulation of sediments when the energy of the transporting medium decreases.

Consolidation

Process where loose sediments are compressed and transformed into solid rock.

Groundwater

Water located beneath the Earth's surface in soil pore spaces and fractures of rock.

Current Velocity

The speed of flow of water, affecting sediment transport and deposition patterns.

Bentonite

A type of clay derived from volcanic ash, known for its high absorption capacity.

Metamorphic Rock

Rock that has undergone transformation due to heat, pressure, and chemically active fluids.

Oxygenic Photosynthesis

The process that produces oxygen as a byproduct, crucial for life on Earth.

Biochemical Sediments

Sediments formed from biological materials, like shells or skeletons of organisms.

Fossil Fuels

Natural fuels formed from the decomposition of organic matter, including coal, oil, and gas.