A "LOST CONTINENT" IN MEXICO

Evening Post, Volume CXXVI, Issue 44, 20 August 1938, Page 27

A "LOST CONTINENT" IN MEXICO

Discovery of a "lost continent" in northern Mexico has been reported tb the Geological Society of America, says the "Christian Science Monitor." The area, was buried 100,000,000 years ago beneath the sediments of an ancient sea that divided North and South America. Evidence of the missing land and sea was uncovered by Dr. Lewis B. Kellum, Associate Professor of Geology at the University of Michigan, and Dr, Ralph Imlay, of the University Museum of Palaeontology. A grant by the society will enable them to complete their studies this summer in the Mexican State of Sonora. . As traced by the geologists, the continent had the shape of a bear's paw pointing east and projecting 250 miles from the southern border of Texas into an ocean that lay in what is how Central Mexico. Layers of different types of rock, each with fossilised marine creatures found during previous expeditions, gave the men their first clues to the discovery. *A shoreline in the southern section of Coahuila, exposed by erosion, gave added information. "Although these studies have no direct economic application," says Dr. Imlay, "they are of interest to both petroleum and mining geologists, be-

cause of their regional scope and bearing on the nature and reflection in overlying strata of a continental margin, and their possible contribution to knowledge of' the factors which control ore deposition. "In geologic exploration for petroleum, the present trend is towards search for buried shorelines. In southern Coahuila erosion has exposed an old shoreline. This- can be examined on the surface over a broad area-and its relation to the structure of the enclosing rocks can be seen. Its projection to the north-east beneath overlying strata may well lead to the disclosure of a reservoir in areas where source beds of petroleum interfinger with,, or overlie j the shore face. "In ore prospecting, knowledge of horizons in which ore deposition commonly occurs may be of prime importance. If mineralisation has been found to be limited to one ,or two horizons in the stratigraphic column, accurate mapping of the area- will narrow the belt to be intensely prospected." Dr. Imlay's project is.part of a programme of geological . studies in northern Sonora outlined to the Geor logical Society of America in 1934 by Dr. Kellum, who suggested that the work be carried out by geologists from several American universities. Dr. Kellum and Dr. Imlay Were asso--ciated in an earlier expedition to southern " Coahuila ahd eastern Durango, which was supported jointly by the Geological Society of America and the University of Michigan.