Report of the Advisory Committee in Seismology

Abstract

The year 1925-26 has been one of noteworthy progress in the study of the zones of movement in California, undertaken by the Carnegie Institution of Washington and the powerful agencies co-operating with it. The purpose of these efforts and the definite plan which has been followed hitherto have been adequately set forth in the earlier reports of this Committee. It is appropriate that this report should indicate some of the more conspicuous results which have thus far been attained, for it is through these that the promise for the future is best appraised. All of the Annual Reports of the Committee have contained brief mention of the progress of the detailed study of the southern portion of the San Andreas rift, the master fault of California, undertaken by Dr. L. F. Noble, of the United States Geological Survey, and his associates. This deep fault, active, as Dr. Noble has shown, through long periods of geologic time, may prove to be the ultimate source and center of the widespread group of movements which this Committee has set itself to study. The report is therefore of fundamental importance to any study of earth movements in this region and of immediate interest to all American seismologists.