REVIEWS 203 



The Coalville Coal Field, Utah. By Carroll H. Wegemann. 

 U.S. Geol. Survey, Bull. 581-E, 1915. Pp. 24, pis. 6. 



The Coalville coal field lies about 30 miles northeast of Salt Lake 

 City, in the valley of Weber River. High-grade sub-bituminous coal 

 has been mined here for more than fifty years. 



The report covers four townships. The rocks of the district include 

 some 8,000 feet of shales and sandstones of Colorado and Montana ( ?) 

 age, which are folded into a slightly overturned and pitching anticline, 

 and are unconformably overlain by 1,000 feet or more of Wasatch con- 

 glomerate. Several transverse and nearly vertical faults of small dis- 

 placement cut the gently dipping limb of the fold. Both the folding 

 and the faulting took place chiefly in pre- Wasatch time, when consider- 

 able erosion was likewise accomplished; but weaker movement of both 

 types appears to have followed the deposition of the Wasatch beds. 



The one productive coal bed, known as the "Wasatch" bed, varies 

 from 5 to 12 feet in thickness. This coal compares favorably in quality 

 with several Wyoming coals. Coal occurs in thinner seams at two other 

 horizons, 2,000 feet above and 850 feet below the "Wasatch" bed, 

 respectively. All three horizons are in the Cretaceous system. 



C. W. T. 



Preliminary Report on the Clay and Shale Deposits of the Province 



of Quebec. By J. Keele. Canada Dept. of Mines, Memoir 



64. Ottawa, 1915. Pp. 280+iv, pis. XXXIV, figs. 13, map 1. 



Describes the clay-bearing horizons and groups producing localities 



by the age of the clay produced. Particular emphasis is laid on the 



Pleistocene clays. A considerable portion of the memoir is devoted to 



the technologic aspects of the clay industries. 



A. D. B. 



"The Pebble Phosphates of Florida." By E. H. Sellards. Florida 

 Geol. Survey, Seventh Annual Report, 1915, pp. 25-116. 

 In an earlier report this writer has discussed the origin of hard-rock 

 phosphates, and this paper extends the study to land-pebble and river- 

 pebble deposits. The land-pebble phosphates are found in the Bone 

 Valley formation of late Miocene or early Pliocene age. They form a 

 portion of a basal conglomerate laid down by a sea advancing over the 

 Alum Bluff formation, a phosphatic marl of late Oligocene age. In this 



