The map, largest one one I could find in time to post, shows the major areas in exploration of the Eagle Ford Trend in South Texas. The trend runs further to the east. The map is from Ross Smith Energy Group . They do not sell maps to the public. For more information please contact Ross Smith directly.
This Eagle Ford shale map shows the trend from Mexico (where it obviously continues across the border as well) to East Texas and beyond into Southwest Louisiana. It shows the low pressure, oily section in the northern region, the condensate section in the middle and the dry gas section at the lower half. Although it is difficult to read, the gray areas are Austin Chalk producing areas. Wherever you find Austin Chalk production you are likely to find Eagle Ford oil as well.
Click image for the largest view.