71

DETAILS OF SECTION.

The line of section has been separated into six divisions corresponding to the different railways along which it extends.

1. FROM TERRELL TO MINEOLA, ALONG THE TEXAS AND PACIFIC
RAILWAY.

This line of sections runs in a nearly east and west course, while the dip of the various beds passed across are within a few degrees of south-east.

From Terrell eastward, to within a few miles of the village of Elmo, the country is comparatively level and covered with the yellow clayey marls of the Ponderosa beds of the Upper Cretaceous.

At mile post 186, or three and one-half miles east of Terrell, the marls are overlaid by a series of thinly laminated dark blue or almost black sandy clays and sands, containing in many places small broken Tertiary fossils. These are altogether bivalves, and are in such a condition that it is difficult to recognize them. No fossils occur close to the line of contact, but are found in a, cut one mile further east, where they are associated with a thin line of small calcareous nodules.

The clays are overlaid by a deposit of brownish gray sands containing numerous calcareous bowlders mixed through the sands, and which are occasionally fossiliferous, containing fragments of gasteropods.

A cut on the railway at the line of contact shows the following section:

Going eastward from this place to Elmo the gray sands and clays of the above section are seen near Muddy Cedar creek. Half a mile north of the road the same class of calcareous bowlders are found forming the bed of the creek, and the same dark clays form the base of the material seen on Walnut creek half a mile east of Elmo station, at which place they are overlaid by a grayish brown sand enclosing bowlders of limestone of the same character as those found in the sands west of Elmo.

About a half mile northwest of Elmo station there is a hill a section of which gives: