358 CARNEGIE INSTITUTION OF WASHINGTON. 



Vaughan, T. Wayland, U. S. Geological Survey, Washington, District of 

 Columbia. Study of the stratigraphic geology and of the fossil corals and 

 associated organisms in several of the smaller West Indian Islands. 



The expedition to the northern Leeward and the Virgin Islands was 

 undertaken with three objects in view, all of which are closely related. 

 These were (1) to study the stratigraphic geology of the islands and 

 to make paleontologic collections with special reference to the strati- 

 graphic occurrence of the fossils, so as to establish a proper basis for 

 correlating the geologic formations in the islands with those of the 

 southeastern United States and of Panama; (2) to make additional col- 

 lections of fossil corals in order to present a more comprehensive and 

 exact account of the successive coral faunas antecedent to the living 

 fauna than was possible with the material already available, and thus 

 trace the history of the development of the coral faunas through Ter- 

 tiary time up to and including the Recent fauna; (3) to studj^ the 

 physiography of the islands in order to get a basis for making deduc- 

 tions as to how the conditions were brought about under which the 

 living coral reefs have formed. As all of these are subjects to which 

 I had already devoted many years of stud}^, the results were expected 

 merely to supplement those of previous work. 



The expedition was rendered possible through a grant from the 

 Carnegie Institution of Washington and through authority given me 

 by the Director of the U. S. Geological Survey to make the studies as a 

 part of my official duties. 



I left New York on January 24, 1914, and visited in succession St. 

 Thomas, St. Croix, St. Christopher, Antigua, St. Bartholomew, St. 

 Martin, and Anguilla. I took steamer for New York from St. Chris- 

 topher and arrived at my destination on March 20. The examinations 

 in the first three of the islands mentioned were cm-sory, but those in 

 Antigua, St. Bartholomew, St. Martin, and Anguilla were careful and 

 should be classed as detailed geologic reconnaissance. Throughout 

 my journey I was the recipient of much courteous assistance and hospi- 

 tality, all of which is gratefully acknowledged. 



As there is already a valuable literature on most of the islands 

 visited, I did not go into unknown territory. It was expected that the 

 general succession of rocks as described by previous investigators 

 would be found to be correct, and this expectation was realized, except in 

 certain instances some of the igneous rocks are geologically younger 

 than appears from the literature; yet as there are igneous rocks bearing 

 the relations attributed to them, this is only a refinement of detail. 



The geologic succession in Antigua, beginning with the oldest rocks, 

 is as follows: (1) old igneous rock, represented by pebbles in the base 

 of (2) stratified volcanic tufifs, sandstones, and clays, with interbedded 

 layers of fresh-water chert; (2) a deposit, at least 400 feet thick, of 

 calcareous clay marl and whitish limestone, which are abundantly fos- 

 siliferous, with an extraordinarily rich coral-reef fauna in the lower part; 



