|Description||The geologic and structure map of Choteau 1 x 2 degree quadrangle (Mudge and others, 1982) was originally converted to a digital format by Jeff Silkwood (U.S. Forest Service and completed by the U.S. Geological Survey staff and contractor at the Spokane|
|Originators||Mudge, Melvill R.; Earhart, Robert L.; Whipple, James W.; Harrison, Jack E.; Munts, Steven R.; and Silkwood, Jeffery T.|
|Publication||U.S. Geological Survey Miscellaneous Investigations Series Map I-1300|
The 'Geologic and structure map of the Choteau 1 x 2 degree quadrangle, Montana: a digital database' report (chot250k.pdf) contains a detailed description of each attribute code and a reference to the associated map symbols on the map source materials. The GIS includes a geologic line work arc attribute table, chot250k.aat, that relates to the chot250k.con (contact look-up table), chot250k.st2 (structure look-up table), chot250k.lgu (linear geologic units table), and the chot250k.ref (source reference look-up table) files; and a rock unit polygon attribute table, chot250k.pat, that relates to the chot250k.ru (rock unit look-up table) and chot250k.ref (source reference look-up table) files; and a point attribute table, chot250kp.pat, that relates to the chot250p.sym (symbol description look-up table) and the chot250p.ref (source reference look-up table).