Sedimentary Rocks and Their Formation

These flashcards cover the key concepts, terms, and definitions related to sedimentary rocks and their formation as discussed in the lecture notes.

Clastic Sediment

Loose fragments of rocks or minerals that are produced by weathering.

Biochemical Sedimentary Rocks

Rocks made from sediments derived from the shells of once-living organisms.

Dissolution

The process where minerals dissolve into water, causing grain surfaces to become pitted.

Oxidation

A reaction during which an element loses electrons, often when combined with oxygen.

Lithification

The transformation of loose sediments into solid rock through processes of compaction and cementation.

Grain Size

The size of fragments or grains in sedimentary rocks, ranging from coarse to fine.

Maturity (in sedimentary rocks)

The degree to which sediment has evolved from the initial weathering event, characterized by sorting and rounding of grains.

Bedding

The layering of sediments that reflects changing conditions during deposition.

Clast

A fragment of rock or mineral.

Physical Weathering

A process that breaks rocks into unconnected clasts of variable sizes.

Differential Weathering

The process where weathering occurs faster at edges and corners of a block than on flat faces.

Glacial Till

A poorly sorted mixture of all grain sizes deposited by glacial ice.

Evaporites

Minerals formed from the evaporation of large volumes of water.

Transgression

A rise in sea level that shifts depositional environments landward.

Regression

A fall in sea level that shifts depositional environments toward the basin.

Sedimentary Structures

Features formed during the deposition of sediments, providing evidence of the depositional environment.

Mud Cracks

Features formed from alternate wet and dry conditions, found in terrestrial environments.

Turbidity Currents

Submarine flows of sediment-rich water that create graded beds.

Chert

A biochemical sedimentary rock made from silica derived from marine plankton.