Glossary of Terms used in MCBONES Research and
Education at the Coyote Canyon Mammoth Site


Alluvial Fan: A fan-shaped deposit of water-transported sediment (alluvium) deposited where a stream’s velocity is abruptly decreased, as at the mouth of a ravine or valley where it runs out onto a plain.

Alluvium:
Water-transported sediment (gravel, sand, and silt).

Bioturbation:
The churning and stirring of sediments by organisms (plants and animals).

Bone Scatter:
The distribution of bones scattered on the landscape or paleosurface (ancient land surface).

Calcium Carbonate Content:
The relative or numerical concentration of calcium carbonate (CaCO3) in sediments (often in the form of calcite), and used to infer pedogenesis (soil formation).

Clast:
An individual particle or rock fragment (e.g. sand, gravel, fossil).

Colluvium:
A general term for unsorted sediments that have been transported down a slope chiefly by gravity (mass wasting) often assisted by running water.

Dewatering Feature:
A soft sediment deformation structure caused by the expulsion of water during compaction of saturated sediment.

Drop Stones:
Isolated pebbles to boulders found within finer-grained water-deposited sediments inferred to have been dropped vertically through a body of water (such as from a floating iceberg).

Dry Sieve Analysis:
A particle size analysis method that separates sediments into different size fractions by shaking through a set of nested sieves (screens).

Erratic:
A rock fragment carried by floating ice, deposited at some distance from the outcrop from which it was derived and generally composed of a different type of rock than the local bedrock.

Extrusive Igneous Rock:
A rock formed from lava that erupted onto earth’s surface and solidified (volcanic rock).

Fanglomorate:
A heterogeneous mixture of gravel and sand sized clasts often fairly angular and cemented together as in a conglomerate, and inferred to have been originally deposited in an alluvial fan.

Fluidized Bed:
A geologic structure formed when a fluid is passed through granular solid material at high enough velocities to suspend the solids and cause the material to behave as though it were a fluid.

Glacial Till:
Unsorted sediment deposited directly by glacial ice.

Humerus:
Upper fore-leg bone.

Hydrofracking (Hydraulic Fracturing):
A process by which hydraulic pressure fractures (breaks) the rock/sediment.

Hydrometer:
An instrument used to measure the specific gravity (or relative density) of liquids.

Hydrometer Analysis:
A particle size analysis method that measures the density of a soil suspension using a hydrometer to incrementally determine the proportion of particle sizes that have settled out of suspension.

Ice Age Flood:
A generic term for cataclysmic glacial outburst floods (or jökulhlaup) that periodically swept across eastern Washington and down the Columbia River Gorge at the end of the last ice age.

Ice Age Flood Deposits:
Sedimentary materials deposited by an Ice Age Flood.

Ice Rafted:
Describes something that floated (rafted) in on an iceberg.

Injection Feature:
A geologic intrusion typically formed from a fluid-filled crack.

Lake Lewis:
A temporary lake, rising to a maximum elevation of 1,250 feet, that repeatedly formed as Ice Age flood waters ponded behind a hydraulic constriction at Wallula Gap.

Loess:
A wind-blown sedimentary deposit made mostly of silt-sized grains.

Lithic Fraction:
The fraction (relative percentage) of different rock fragment types.

Liquefaction:
A phenomenon whereby saturated or partially saturated sediment looses strength and stiffness in response to earthquake shaking or other rapid loading, causing the sediment to behave like a liquid (as in a fluidized bed).

Mandible:
Lower jaw bone.

Radiocarbon Dating:
The determination of the age (date) of a specimen from the relative proportions of its carbon isotopes carbon-12 and carbon-14.

Particle Size Analysis:
The measurement of sediment particle (clast) sizes to help classify the sediment and sedimentary environments.

Paleobiology:
The study of ancient life (as opposed to neobiology).

Paleoclimate:
Climatic conditions of the ancient past.

Paleoecology:
The study of the relationships of ancient organisms with each other and their environment.

Paleoenvironment:
The environment of the ancient past.

Paleosol: A former surface soil, now buried within the stratigraphy.

Slopewash: Sediments that have been transported down a slope by non-channeled running water, (i.e. sheet erosion).

Stable Isotope Analysis:
Laboratory measurement of stable isotopes (that do not change over time like radioactive isotopes) to determine the isotopic signature of key elements (e.g. carbon, nitrogen, sulfur, oxygen and hydrogen) within a specimen.

Stratigraphy:
The arrangement of geologic layers (or strata).

USGS:
United States Geological Survey — a Federal Agency that provides impartial information on the health of ecosystems and environment, natural hazards, natural resources, and impacts of climate and land-use change.

Wet Screening: Washing excavated sediments through a screen using a fine spray of water.

X-Ray Fluorescence (XRF) Analysis:
An analytical method for quantitative and qualitative analysis of elemental concentrations.