The subsurface database has been completed for the project. An ACCESS database converted to PC-Arcview is being used to manage and interpret the data. Well data and base map data have been successfully imported into Arcview and customized to meet the needs of this project. Log tops and other data from all of the exploration wells in the area have been incorporated into the database, except for some wells that have no available logs or other information. All of the four 30? X 60? geologic quadrangles have been scanned to produce a digital surface geologic database for the Crow Reservation and all are nearing completion. Formal technical review prior to publication has been completed for all the quadrangles; Billings, Bridger; Hardin, and Lodge Grass. All four quadrangles have been received from the printer and are nearly ready for distribution. Field investigations were completed during the third quarter, 1997. With the help of a student field assistant from the Crow Tribe, the entire project area was inventoried for the presence of valley-fill deposits in the Kootenai Formation. Field inventory has resulted in the identification of nine exposures of thick valley-fill deposits. These appear to represent at least four major westward-trending valley systems. All the channel localities have been measured and described in detail and paleocurrent data has been collected from all but one locality. In addition, two stratigraphic sections were measured in areas where channels are absent. One channel has bee traced over a distance of about 60 miles and exhibits definite paleostructural control. An abstract describing this channel was submitted and the paper was presented at the Williston Basin Symposium in October, 1998. Surface occurrences of channels have been correlated with subsurface occurrences and subsurface valley-fill isopach maps and structural maps have been completed. These maps identified several potential exploration leads that were evaluated using soil gas geochemistry. The initial sampling program was completed early in early August, 1999. Of three geologic leads identified, one, the Crow Agency prospect, resulted in a significant butane and propane soil geochemical anomaly. Some follow-up sampling was necessary to fully delineate the anomaly. The follow-up sampling is now complete and better defines the extent of the anomaly. Statistical evaluation indicates that surface and soil conditions can not explain the anomaly, and that therefore, it most likely indicates the presence of a subsurface hydrocarbon accumulation.