Glossary

A few useful definitions...

chert

a sedimentary rock made of microcrystalline quartz, it forms from the skeletons of microscopic marine organisms

discharge

the rate of flow, discharge is usually measured in cubic feet per second (cfs) or cubic meters per second (cms)

ecosystems

(Greek, oikos, house + systema, that which is put together)

a major interacting system involving both organisms and their physical environment

geographic information system (GIS)

a system used to input, store, retrieve and analyze spatial data; click here for an example GIS

geomorphology

(Greek, geo, earth + morphe, form + ology, study of)

the systematic description, analysis, and understanding of landscapes and the processes that change them; this is the wing of geology that studies topics like how rivers work and what triggers landslides

habitat

(Latin, habitare, to inhabit)

the environment where an organism lives and is usually found; examples of stream habitats are riffles, runs, and pools

karst topography

rugged, hilly landscape formed by the underground dissolution of limestone and dolostone, karst landscapes have springs, caves, and sinkholes; click here for links to other web pages about karst landscapes

Paleozoic

the era of geologic time between 570 and 245 million years ago

run

a segment of the channel with depths and velocities intermediate between the rough, shallow water of riffles and the slow, deep water of pools; runs usually have a rectangular or trapezoidal cross section and lack a focused current

radiocarbon dating

a method of calculating the age of organic material based on the number of carbon atoms that have undergone radioactive decay

stratigraphy

the study of layers of rock or sediment to learn about the geologic history of an area and past environmental conditions