20 abstracts: geology 



the north is recorded in northward splitting and divergence of breaches 

 and the relatively rapid rate of the uplift is shown by a wide interval 

 in the north below the upper group of Algonquin beaches. 



The opening of the outlet at North Bay marks the final disappearance 

 of the ice sheet from the Great Lakes region and the end of its influence 

 in lake history. At this stage the upper lakes, known as Nipissing 

 Great Lakes, were not very different from the present Great Lakes 

 except that their outlet was eastward through the Mattawa and Ottawa 

 rivers to the sea near Ottawa. Uplift of the land finally changed the 

 outlet of these post-glacial lakes from North Bay to Port Huron and 

 established the present system. 



In the closing chapter the possible causes of the deformation of 

 shore lines, such as resilience with ice removal following depression by 

 ice weight, eustatic movements, and crustal creep are considered, but 

 final conclusions are not reached. 



F. B. T. 



GEOLOGY. — Contributions to Economic Geology, 1918, Part II, Min- 

 eral Fuels. M. R. Campbell, and David White. U. S. Geo- 

 logical Survey Bulletin 581. Pp. 187, 11 plates, 6 text figures. 

 1915. 

 This volume contains two classes of reports on occurrences of oil and 

 coal: (a) Short reports giving comparatively detailed descriptions of 

 fuel resources that have economic interest but are not of sufficient impor- 

 tance to warrant a lengthy report; (b) preliminary reports on econo- 

 mic investigations, the results of which are to be published later in 

 more detailed form. The papers included in the volume are the fol- 

 lowing: 



Woodruff, E. G., and Day, D. T. Oil shale in northwestern Colorado and 

 northeastern Utah. 



Lupton, C. T. Oil and gas in the western part of the Olympic Peninsula , Wash- 

 ington. 



Barnett, V. H. The Moorcroft oilfields, ("rook County, Wyoming. 



Barnett, V. H. Possibilities of oil in the Big Muddy Dome, Converse and Na- 

 trona Counties, Wyoming. 



Pack, R. W., and English, W. A. Geology and oil prospects in Waltham, Priest, 

 Bitterwater , and Peachtree Valleys, California. 



Wegemann, C. H. The Coalville coalfield, Utah. 



E. S. B. 



