Week 2 Vocab: Death and Fossilization

Taphonomy

The study of all natural processes that involve

an organism after it dies -- this includes how it

decays, is scavenged by other organisms,

becomes fossilized, and erodes

Disarticulated

A skeleton that is separated into its various components

Plastic deformation

Taphonomic alteration to the shape of a fossil that does not result in fracture or breakage; usually the result of prolonged exposure to pressure

Fluvial deposits

Sediment deposited by rivers and

streams. Good for fossil preservation.

Lacustrine deposits

Sediment deposited in lake environments; excellent for preserving soft tissues like hair or feathers in the fossil.

Sedimentary rocks

Rocks that form when mineral and organic

particles accumulate and become either

cemented or compacted together.

Igneous Rocks

Rocks formed by cooling magma (under ground) or lava (above ground).

Metamorphic Rock

New rocks formed by the chemical or physical alteration of other rocks by extreme heat and pressure.

Coal

A combustible sedimentary rock that forms from dead vegetation (usually from wetland forests) that are deeply buried, heated, and pressurized

Limestone

A kind of sedimentary rock that is typically composed of skeletal fragments from marine organisms

Mudstone/shale

A type of fine-grained sedimentary rock that forms in slow-moving water; typical of a lake or floodplain deposit.

Sandstone

A type of sedimentary rock composed of sand-sized grains; typically forms in fast moving water such as in rivers, or in alluvial fans, lakes, deserts, beaches, or tidal flats.

Permineralization

Fossilization processes in which minerals are carried by water into the internal spaces of an organism and then solidify

Replacement

Fossilisation process in which the original bone

gradually decays and minerals fill the space that

the bone once occupied

Overburden

The earthen debris that overlays a bonebed

Long-bone alignment

The degree to which the axes of long bones (usually limb bones) share a similar orientation within a given deposit; in a fluvial context, long-bone alignment is often taken as an indicator of current direction and force