REPORT OF THE STATE GEOLOGIST. lxxxi 



surface toward the southeast is less than the dip of the strata in the 

 same direction, and as there have been no disturbances of sufficient 

 magnitude to complicate the geology, except the uplift which brought 

 up the Balcones (and that of Pilot Knob and similar areas if it be later, as 

 it possibly is), we find the outcropping edges of the beds of earlier and 

 earlier age as we pass from the coast to the interior. These various 

 beds are exposed in bands of less or greater width, which are, in a gen- 

 eral way, parallel with the present Gulf coast. The formations com- 

 prised in this belt are: 



1. Coast Clays, . . . Port Hudson — Quaternary. 



2. Orange Sands, . . . Quaternary. 



3. Fayette Beds, .... Grand Gulf — Miocene. 



4. Timber Belt Beds, ) ~, ., „ 



_ . „ J. Claiborne, etc. — Eocene. 



5. Basal Clays, ) 



6. Black Prairie, .... Upper Cretaceous. 



7. Grand Prairie, . . . Lower Cretaceous. 



The relative position of these formations is indicated upon the map 

 accompanying the First Annual Eeport. 



The Coast Clays, which are the most recent of these, and which form 

 a part of the present floor of the Gulf, are very impervious, variously 

 colored, calcareous clays, which often form bluffs along the bay shores 

 and river banks. The level belt of this formation varies from fifty to 

 one hundred miles in width. 



The Orange Sands underlying these are mottled red and white sands 

 which are well exposed below Willis, on the International and Great 

 Northern Kailroad, and at other places. 



The Fayette Beds, which underlie these, are made up also of sands 

 and clays, but of entirely different character and structure. The sand 

 greatly predominates, especially in the centre, where great beds of sand 

 and sandstone and millstone grit occur. 



The clays, instead of being massive, are usually thinly laminated and 

 of very light color wherever exposed to the air, and are found both un- 

 derlying and overlying the sands, as well as interbedded with them. 

 They extend along the line of the Houston and Texas Central Eailway 

 from Waller to near Giddings. A study of these beds in the vicinity 

 of Ledbetter showed nearly four hundred feet of sandy strata included 

 between the two series of clays. 



The dip of the strata toward the Gulf is not much greater than that 

 of the surface of the country. For this reason the exposure of the sand 



6-geol, 



