Context: I have a postgres table with > 110K rows of permitted wells. Among the columns are lat, lon, utm_easting, and utm_northing; for example:
latitude | longitude | utm_easting | utm_northing -----------+------------+---------------+----------------
41.040000 | 117.310000 | 473829.030000 | 4543648.900000 40.980000 | 117.410000 | 465323.370000 | 4537116.040000 40.930000 | 117.450000 | 462092.370000 | 4531365.620000 40.890000 | 117.080000 | 492442.050000 | 4526893.330000 40.890000 | 117.080000 | 492442.050000 | 4526893.330000 40.910000 | 117.160000 | 485988.390000 | 4529277.070000 40.920000 | 117.150000 | 487182.810000 | 4530107.450000 40.920000 | 117.160000 | 485989.150000 | 4529677.930000 40.970000 | 117.140000 | 488103.560000 | 4535409.570000 41.650000 | 118.520000 | 373435.960000 | 4612467.900000 Because these data come from a Nevada state agency I can safely assume UTM Zone 11, but I'd like to determine if the datum is NAD83 (in meters) which I suspect it is, or NAD27 (in feet). What is the most simple way of determing the datum and units. Once I know the datum and units I'll learn how to associate these data with GRASS. My purpose is to produce maps of the depth to bedrock and static water level depth by county and basin. Since this is all new to me I need to learn it one step at a time. All pointers, suggestions, recommendations, and other advice is welcomed. Rich _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
