The Geology of the Southeastern Portion of the Glendale Quadrangle and the Northeastern Portion of the Los Angeles Quadrangle

The area described in this report is that part of the Glendale and Los Angeles Quadrangles bounded on the north by York Boulevard, on the west by the Los Angeles River, and on the south by North Broadway. This area is about six square miles. The maps used are the U.S.G.S. sheets of recent publication which have a scale of 2000 feet to the inch. The contour interval is 5 feet up to elevations of 500 and then it is 25 feet. The map is very satisfactory and is up to date except for very recent streets and buildings. This area was included in Ralph Arnold's report, U.S.G.S. Bulletin 103, on the Los Angeles Oil fields. However, his report was only of a reconnaissance nature and was made on a map with a scale of one inch to the mile. Hence very little of the detailed structure of this area was shown. In 1928 Hampton Smith of the California Institute of Technology did some work of a detailed nature, but no finished report was made. The hills to the east of the Southern part of this area, lying in the Alhambra Quadrangle, were works of Mr. Lewis Gazin of the California Institute of Technology. His report was accessible to the writer, and consequently, as some of the same formations occur in both areas, the writer has used the same names for the formations as are used in Mr. Gazin's report. The writer and his classmate, John Daly worked together, in doing the field work, however each kept separate complete notes and maps in order to make independent reports. The writer benefited from many discussions which arose over the questionable parts of the area. He is also indebted to Dr. J. P. Buwalda for many suggestions on the execution of the work. The geological mapping was carried on with the aid of a Brunton compass. The mapping of locations was facilitated by the fact that the numerous streets and roads in the area are almost all shown on the map and are easily recognizable. The problem was worked with a view toward mapping the aerial extent of the formations, deciphering thus underground and geological history. The area was worked in as much detail as the map scale and the available time permitted. The evidence of the underground structure was principally obtained from the numerous road cuts existing in most of the area. Natural exposures, due to erosion, are not plentiful, but are the only ones present in certain localities. The numerous buildings and retaining walls also hindered the collecting of data.