This sub-series contains files related to Bartle's employment and consulting in oil and gas exploration. Files include correspondence, reports, maps, data, and photographs of drilling sites. Additional files about oil and gas exploration can be found in the map sets sub-series.

This sub-series contains files related to Bartle's employment and consulting in oil and gas exploration. Files include correspondence, reports, maps, data, and photographs of drilling sites. Additional files about oil and gas exploration can be found in the map sets sub-series.

This sub-series contains files related to Bartle's employment and consulting in oil and gas exploration. Files include correspondence, reports, maps, data, and photographs of drilling sites. Additional files about oil and gas exploration can be found in the map sets sub-series.

This sub-series contains files related to Bartle's employment and consulting in oil and gas exploration. Files include correspondence, reports, maps, data, and photographs of drilling sites. Additional files about oil and gas exploration can be found in the map sets sub-series.