Science Topics term usage 2007-04-19

This analysis excludes the activity of search-engine spiders, USGS users, and transactions resulting in errors.

(Table shows only the 40 most frequently chosen terms.)

167	river systems
137	geographic information systems (GIS)
130	earthquakes
106	volcanoes
50	earthquake occurrences
33	water quality
30	geology
30	climate change
26	earth structure
26	stream discharge
25	geologic history
24	streamflow
23	surface water (non-marine)
23	tectonic processes
23	tsunamis
22	floods
21	ground-water flow
20	sediment transport
20	animals
20	acid deposition
20	contamination and pollution
19	map coordinate systems
19	geologic structure
19	ground water
19	hydrology
18	global warming
18	oil resources
18	rocks and deposits
18	sedimentation
17	maps and atlases
17	coastal zones
17	mineral resources
17	endangered species
16	water supply and demand
16	invasive species
16	human impacts
16	water resources
16	cartography
15	global change
15	geography

Science Topics term usage Thursday, 2007-04-19