136 H. E. Gregory — Geologic Reconnaissance of the 



ground mass reveals the presence of plagioclase feldspar, bio- 

 tite and magnetite in addition to much hornblende and a limited 

 amount of pyroxene. Fragments of calcite and of an unde- 

 termined zeolite were observed in one of the three sections 



Fig. 8. 



THE PERUVIAN EXPEDITION OF 1912 



UNDER THE AUSPICES OF 



YALE UNIVERSITY &. THE NATIONAL GEOGRAPHIC SOCIETY 



HIRAM BINGHAM. DIRECTOR 



APPROXIMATE 

 POSTION 

 LAT. 13° 42* S 

 LONG. 72*2 



MAP OF A PORTION OF THE PROVINCE OF PARURO, PERU 

 SHOWING FOSSIL LOCALITY NEAR AYUSBAMBA 



Topography by K.C. Heald Ct 



and Carlos Duque 

 Geology by Herbert E Gregory 



interval, 20 feet. Doutajru sea. Level (levels 

 brou.gh,t from, Cazco by asteroid) 



Shaded area indicates 

 Lacustrine deposits 



examined. The rock is therefore to be classed with dioritic 

 or andesitic porphyries. The relative abundance and localiza- 

 tion of these diorite bowlders suggest the possibility that an 

 intrusive mass now covered by superficial debris exists to the 

 west of Calvo brook. 



The structural relations of the sandstones were not studied 

 in sufficient detail to permit of a definite statement regarding 



