The table of decimal degrees (DD) longitude and latitude coordinates below is intended (1) for use in the GIS mapping of obsidian sources, and (2) for determining the distance from a source to an archaeological site or artifact location. When multiple coordinates are listed for the same geochemical source location, this indicates that characterized samples that were correlated with the source were collected at more than one locale. In the case of some sources associated with volcanic ashflows or with fluvial/pluvial systems, the geographic range and the boundaries of a source may be considerable and the calculation of a firm distance figure may be difficult to impossible. In this case, we suggest that you use the closest reported outcrop to calculate the distance. Please note that the locations recorded below are only those at which geologic source samples have been collected - the actual geographic range of any specific source may be incompletely represented by the sample locations. These data are the same ones used to create obsidian source location maps for the United States Obsidian Source Catalog. Can't find a source listed below? First, check the state source listings at the U.S. Obsidian Source Catalog to see if the source that you're looking for is listed below under another name. Many of the obsidian sources are in the Far West appear under a variety of different names. Still no luck? Contact us here at the lab and we'll attempt to clear things up.

If you have Google Earth (a free geographic viewer available from Google) installed on your computer, you can search for sources using the longitude-latitude coordinates posted below. In the search box of Google Earth, simply type in the decimal latitude and longitude coordinates (separated by a space). For example, the location of Oregon's Big Obsidian Flow as shown below is < -121.23 43.69 >. To enter these coordinates into Google Earth, type < 43.69N 121.23W > (latitude must be first).