Earth

Three primary sources of information can be used to answer the question "Could It Happen Here? Tsunamis That Have Struck U.S. Coastlines": (1) tsunami catalogs of historical events, (2) the age of geologic deposits left by great earthquakes and tsunamis...
Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot, mineral...
The Palmer Drought Severity Index was developed by Wayne Palmer of the U.S. Weather Bureau (now the National Weather Service) in the 1960's and uses temperature and rainfall information in a formula to determine dryness. It has become the semi-official...