THE 
AMERICAN GEOLOGIST. 
Vol. XXV. JUNE, 1900. No. 6 
REPORT OF A GEOLOGICAL RECONNOISSANCE 
IN WESTERN SOCORRO AND VALENCIA 
COUNTIES, NEW MEXICO. 
By C. L. Hereick, President of the University of New Mexico. 
(Plates VIII and IX.) 
The time of elaborate journals of geological discovery has 
passed and there are few regions that are so inaccessible or 
little known that the casual record of what can be gathered 
by a rapid journey of exploration can prove of much real 
value. The following pages, however, while they present the 
geological work done along the route of a journey taken in 
the interests of the territorial university through a portion of 
the least known region of the territory of New Mexico, rest 
upon a foundation of more detailed study laid during the 
course of the work of the university geological survey for the 
past few years. 
The little party started by wagon from Albuquerque on 
the seventh day of December, 1899, and journeying westward, 
accomplished the traverse of the territory to its western 
boundary in five days, including stops and side trips. The 
return journey, by a different route, was made in the same 
time. Prior to this excursion several other shorter visits had 
been made to places along the route. The localities men- 
tioned may be identified by reference to the accompanying 
sketch maps. 
A part of the region covered in these excursions has been 
described by captain Button in his report on the Mount Tay- 
