Types of rocks & Sediment KL Oceanography

Rock V. Mineral Rock= hard, solid substance composed of one or more minerals 3 Types: Igneous Metamorphic sedimentary

Rock V. Mineral Mineral= naturally occurring inorganic (non-living) solids composed of one or more elements naturally occurring in the earth’s crust…they make up rocks. Ex> quartz, garnet, olivine, magnetite, feldspar

3 Types of Rock Igneous= come from hot fluid magma (the mantle) that cools and hardens If it cools fast extrusive= small grains Ex> Basalt, obsidian If it cools slowly and inside the continental plate intrusive=large grains EX>rhyolite, andesite, granite

3 Types of Rock Metamorphic= formed under very intense heat and pressure over long periods of time forms deep in the earth’s crust subduction zones. Ex> marble, schist, gneiss

3 Types of Rock Sedimentary= Compacted sediment from other rocks or minerals already present on or near the Earth’s surface. Ex> sandstone, limestone Sediment= particles of rocks carried along and deposited by water, wind or glaciers. Small pieces of rock or shell that are broken down over time by erosion Sand on our beaches is sediment of various types Depends on the origin of the parent rock

4 Types of Ocean Sediment Lithogenous comes from weathering and erosion in the mountains and contains lots of Quartz, Feldspar and Clay Rivers carry 15 billion tons of Lithogenous sediment to the ocean the most abundant type of sediment found in the ocean

4 Types of Ocean Sediment Biogenous Comes from biological organisms’ shells &/or skeletons contain silica or calcium carbonate Creates “Ooze” as it accumulates into layers on the sea floor Calcareous- Calcium carbonate secretors Siliceous- from diatoms Ooze turns into petroleum and natural gas over millions of years.

4 Types of Ocean Sediment Hydrogenous result from chemical reactions in seawater which cause minerals to come out of solution and form particles that settle to the bottom Comes from dissolution of submerged rock, new crust formation and hydrothermal vents Manganese Nodules Metallic Sulfides

4 Types of Ocean Sediment Cosmogenous sediment that comes from outer space, usually in cosmic dust that results from collisions of asteroids, comets, meteorites, etc. Rarest form of sediment (least abundant)