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CARBONIFEROUS ROCKS 



Rivers is more unequivocally displayed at St. Joseph's, than at any locality 

 previously examined on the Missouri. The colour of the deposit, its chemical 

 composition, the appearance and state of preservation of the shells, are so perfectly 

 analogous at the two localities, that, placed side by side in a collection, it would be 

 hardly possible to distinguish them. Both have, in all probability, been derived 

 from the destruction of the marly beds of the carboniferous formation. 



The barrier which arrested the waters in which this fine loamy sediment was 

 diffused, must have been at the narrows near the mouth of Little Tarkio River ; 

 where the distance across from bluff to bluff hardly exceeds two miles. 



Coal is reported to have been found some distance west of the Missouri River, 

 opposite St. Joseph's ; but as I had no opportunity of visiting the locality, I am not 

 able to vouch for the correctness of the statement. If the report, however, be true, 

 the coal will probably prove to be equivalent to the nine-inch seam, observed by 

 Mr. Jones three or four miles back from the river, between St. Joseph's and 

 Weston. 



Near Independence Creek, of Nicollet's map, the strata again rise, so that, below 

 its mouth, the buff Fusulina limestone has an elevation of one hundred and fifty 

 feet, resting, as usual, on a bench of cherty limestone, with a rugged surface. There 

 is a second bench of similar limestone in the lower third of the Section ; say from 

 thirty to forty feet above the bed of the river. The intervening space is occupied 

 by marls and shales, mostly concealed, and alternating with occasional bands of 

 limestone. Twenty-five feet above the water-level, is a bed of gritstone, lying 

 within a few feet of the lowest bench of limestone. (See Section No. 23, M.) 



In the vicinity of Cow Island, and above and below Weston, the benches of 

 limestone can be traced in long ranges of bluffs, first on one side of the river, and 

 then on the other. The principal bench of rugged limestone is usually from twenty 

 to forty feet above the water-level ; while, near the margin of the river, a band of 

 compact, hard limestone usually shows itself, which, as it cleaves very readily into 

 regular prismatic blocks, would make an excellent building material. (Section 

 No. 22, M.) At Fort Leavenworth, this bed lies partly under the water, covered with 

 layers of dark bituminous and gray argillaceous shales, over which is a regular wall 

 of limestone, forming a slight anticlinal axis below the Fort. The Fusulina lime- 

 stone is also here in its usual position. (Section No. 21, M.) 



Just below the mouth of Little Platte River, on the left bank of the Missouri 

 River, two principal limestone benches are traceable ; the most conspicuous lies 

 thirty feet above the water-level ; the other, from thirty to fifty feet higher. (Sec- 

 tion No. 20, M.) Towards the top of the exposure, we found five large specimens of 

 Productus cora and P. punctatus; also P. costatus (?) , Spirif&r fasciger (?) , and 

 Terebratula plano-sulcata. Of these, the Productus punctatus is the most abundant. 

 These calcareous beds can be traced, with little variation, as far as the Kansas or 

 Kaw River,* where the bench of rugged limestone comes down to the water-level. 

 The strata again rise, however, so that, three or four miles lower down the stream, 

 near Randolph, its base is from ten to twelve feet above the surface of the water. 



* The distance between the Little Platte and Kansas Rivers is represented too short on Nicollet's Map ; 

 it is ten miles, either by land or water. 



