558 shaw: NEW AREA of carboniferous 



found nearby. Although the quality is fairly good and no other 

 sources of coal are within 20 or 30 miles, the facts now at hand 

 would not warrant extensive prospecting. A few tons of coal 

 have been mined and are reported to have burned very satis- 

 factorily. Most of it was used in houses, but some is said to 

 have been tested on a small river steamer. This coal should 

 not be confused with brownish lignite, such as occurs a few miles 

 to the south in the Cretaceous and Tertiary formations of the 

 Gulf embayment and is not at present of much economic value. 



Although the coal may not have a great extent or thickness, 

 it is worth noting that here is an area of Pennsylvanian coal not 

 described or included in any of the discussions of the coal resources 

 of the United States. The coal in places is no doubt workable 

 under present conditions, is almost certain to prove of some value 

 as the richer supplies of the country are exhausted, and may 

 lead to the discovery of more extensive concealed deposits. The 

 outcrop is about 7 miles northeast of Brookport, only 4 miles 

 from the Ohio River, and far south of the main coal-producing 

 region of Illinois. 



The new data show that the general structure of the Paleozoic 

 rocks in the southern end of Illinois is not monoclinal and north- 

 ward dipping, with faults and modifying folds here and there, 

 as one would infer from the available geologic maps. Instead it 

 approaches a general anticlinal form. Beds that at McLeans- 

 boro, near the middle of the great Eastern Interior coal basin, lie 

 2,000 feet below the surface and several hundred feet below the 

 formations containing the main coal beds, rise southward and 

 outcrop north of Massac County, and it has been supposed that 

 still older formations are concealed beneath the Gulf embayment 

 deposits. It is now found, however, that not only are the bed- 

 rocks under these Cretaceous and Tertiary deposits exposed in 

 eastern Massac County, but that they belong rather high among 

 Paleozoic rocks, being in part upper Mississippian and in part 

 basal Pennsylvanian. 



The finding of outliers of Paleozoic rocks in the upper end of 

 the Gulf embayment in Massac County and elsewhere, together 

 with the fairly definite determination of the slope of the Paleo- 



