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By Alex GorskyMy internship at the Environmental Protection Agency was a whirlwind of excitement and opportunity. I was able to meet so many interesting and important people. Not only did I meet directors of each of the EPA’s program offices, I also got to meet Administrator Lisa Jackson. At the…
A landslide is defined as, the movement of a mass of rock, debris, or earth down a slope. (Cruden, 1991). Landslides are a type of "mass wasting" which denotes any down slope movement of soil and rock under the direct influence of gravity. The term "landslide" encompasses events…
You can purchase topographic maps several ways: Download or online from the USGS Store at http://store.usgs.gov Click on Maps in the left margin or click on the Map Locator near the center of the screen. Topographic maps in GeoPDF format are available for free download by using the Map…
Not specifically. Our charge is to understand characteristics of the earth, especially the earth's surface, that affect our Nation's land, water, and biological resources. That includes quite a bit of environmental monitoring. Other agencies, especially NOAA and NASA, are specifically funded…
An earthquake is caused by a sudden slip on a fault . The tectonic plates are always slowly moving, but they get stuck at their edges due to friction. When the stress on the edge overcomes the friction, there is an earthquake that releases energy in waves that travel through the earth's crust…
Sometimes, yes. A few historic large regional earthquakes (>M 6) are considered by scientists to be related to a subsequent eruption or to some type of unrest at a nearby volcano. The exact triggering mechanism for these historic examples is not well understood, but the volcanic activity probably…
During the three giant caldera-forming eruptions that occurred between 2.1 million and 640,000 years ago, tiny particles of volcanic debris ( volcanic ash ) covered much of the western half of North America, likely a third of a meter deep several hundred kilometers from Yellowstone and several…
Lava and Lava Flows The temperature of basalt lava at Kilauea reaches 1,160 degrees Celsius (2,120 degrees Fahrenheit). -- USGS/VHP Website, 1998 The tube system (lava tubes) of episode 53 (Pu'u O'o eruption, Hawaii) carried lava for 10 kilometers (6 miles) from the vent to the sea. So…
The short answer is - a rolling motion means you are probably far away from the earthquake; a sharp jolting motion means you are probably close to the earthquake. Three factors primarily determine what you feel in an earthquake: Magnitude (you feel more intense shaking from a big earthquake than…
Mussels are also called 'bivalves'. This means they have two shells or valves (a right valve and a left valve). The zebra mussel gets its name because of the dark, striped pattern on each valve. Usually the shell is a light color (tan, beige) with the zig-zag stripes. However, some are…
Yes. The main body of subsurface water is found in the saturated zone of aquifers. Aquifers can be only a few feet below the surface or more than a thousand feet deep. Aquifers are the primary source of drinking water in arid and semi-arid parts of the United States where the amount of surface water…
As an unbiased, multidisciplinary science organization that focuses on biology, geography, geology, geospatial information, and water, the U.S. Geological Survey (USGS) is dedicated to the timely, relevant, and impartial study of the landscape, our natural resources, and the natural hazards that…