REVIEWS 305 



Paleocene Deposits of the San Juan Basin, New Mexico. By W. J. 



Sinclair and Walter Granger. Bull. Am. Museum Nat. 



History, XXXIII, Art. XXII, June 3, 1914, pp. 297-316, 



Pis. XX-XXVII, figs. 2. 

 The Paleocene Puerco and Torrejon formations are exposed along 

 the south and southwest margin of the San Juan Basin in northwestern 

 New Mexico. There is an unconformity, shown both by erosion and 

 by an abrupt faunal change, at the base of the Puerco (unconsolidated 

 clays and channel sandstones) which appears "to be the dividing line 

 between Cretaceous and Tertiary in this region." The Torrejon suc- 

 ceeds the Puerco without lithologic or stratigraphic break. The bound- 

 ary between the two depends on fossil evidence, and is not exactly 

 determined. Basal Wasatch sandstone and in some places seemingly 

 younger sandstone unconformably overlies the Torrejon. A fluviatile 

 origin is indicated for both the Puerco and Torrejon. 



Two Puerco fossil levels, to the upper of which Polymastodon is 

 confined, were accurately located. Fossil plants were found in the 

 Puerco. Torrejon fossils were discovered much below previously located 

 horizons. The sections measured by the authors are compared with 

 Gardner's Rio Puerco and Arroyo Torrejon sections. The pre-Puerco 

 beds are, beginning with the oldest exposed, clays, conglomerate, clays, 

 conglomerate sandstone with silicified logs and pebbles of volcanic 

 rocks. Dinosaur remains occur in both clay horizons. "More or less 

 of this series of beds may be correctable with the Animas formation." 



V. O. T. 



Cement Materials and Industry in the State of Washington. By 

 Solon Shedd. Bull. No. 4, Washington Geol. Survey. 

 Pp. 268, figs. 10, pis. 21. Olympia, 1913. 



Increasing importations of cement from California and Europe have 

 led to investigation of the state's possibilities in cement production. 

 The results are given in this, the fourth of a series of bulletins on natural 

 resources. The work was directed by Solon Shedd, assistant state 

 geologist and professor of geology, Washington State College. 



More than one-third of the report is taken up with chapters on the 

 history of the cement industry, various kinds of cements, and origin and 

 composition of raw materials. Manufacturing processes are described 

 briefly and there is an excellent chapter on the factors to be considered 



