This slide shows the different thicknesses of the sediments in the fore-deep basin. You can see that the thickest part of the basin is in the west, adjacent to the front of the fold and thrust belt. In the south you can see the paleo-Gulf of Mexico. This extension extends barely northward into southern Arizona. Sedimentary deposits were thickest in the west and thinning to the east. Courtesy of Prof. Burchfiel.