A gravity survey was performed through a portion of the southern Elsinore fault zone where the fault has been obscured by a thick accumulation of alluvium. The purpose of this survey was to try to delineate the exact location of the Elsinore fault as it crosses old highway. 80, east of Ocotillo, California. One traverse consisti11g of 55 stations was performed, beginning 0.6 miles sout!:west of ths town of Ocotillo, following old highway 80 4.2 miles to the northeast. The resulting rofile shows a marked increase of 17 milligals from west to east, suggesting a normal step-fault structure. The profile was not carried out far enough to the east to determine the exact amount of throw and the exact position of the fault, but a western-most limit and a minimum throw of 3300 feet can be concluded from the available data.
