Earth and Planetary Sciences ETDs

Publication Date

Spring 5-18-1953


The San Juan Basin is located in northwestern New Mexico and southern Colorado and is physiographically a part of the Colorado Plateau province.

The Upper Cretaceous Pictured Cliffs sandstone is exposed around the perimeter of the San Juan Basin and is present throughout the greater part of the Basin in the subsurface. This economically important gas-bearing sandstone is situated in the structural basin in which the strata are upturned on the basinward flanks of the nearby Laramide cliffs.

Five possible origins for the Pictured Cliffs gas are presented: from the underlying Lewis shale, from within the Pictured Cliffs sandstone, from the overlying Fruitland formation, from formation below the Lewis shale, and from formations above the Fruitland Formation.

Degree Name

Earth and Planetary Sciences

Level of Degree


Department Name

Department of Earth and Planetary Sciences

First Committee Member (Chair)

Sherman Alexander Wengerd

Second Committee Member

Stuart Alvord Northrop

Third Committee Member

Vincent Cooper Kelley

Project Sponsors

Standard Oil and Gas Company




Pictured Cliffs, San Juan County, Lewis Shale, Fruitland Formation

Document Type


caldwell_fig_12a.tif (68642 kB)
Electric Log and Lithologic Cross Sections

caldwell_fig_12b.jpg (26706 kB)
Electric Log and Lithologic Cross Section

caldwell_fig_13.tif (1705911 kB)
Subsurface Structure-Contour Map

caldwell_fig_14.tif (1705109 kB)
Pressure-Contour Map