Tutor profile: Patricia D.
How are sedimentary gold deposits formed?
Erosion and re-deposition. Free gold is eroded from hard rock deposits by turbulent surface and groundwater. The mobilized free gold is deposited in calmer water environments such as sandy lake beds. Over time these sandy lakebeds are compressed into sandstone.
Subject: Environmental Science
What is a method for removing hydrocarbon contamination from soils?
Soil Vapor Extraction. Lengths of horizontal and vertical perforated pipe are installed in the ground. A blower system is connected to the piping to force fresh air through the perforated pipes. This forced air removes the hydrocarbons from the soil by volatilization of the compounds.
Subject: Earth Science
What is the cause of earthquakes in western New York?
Glacial Rebound. The crust of the earth in this region is still rising due to the removal (as glaciers melted over 10,000 years ago) of surface weight associated with glaciers over 10,000 years ago. This movement of the earths layers can cause earthquakes.
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