Linear features of the region of the northern Gulf of California as mapped from erts-1 satellite imagery

Abstract

Under a NASA contract, (Principal Investigator, J. R. Hendrickson) the University of Arizona is engaged in Oceanographic studies in the Northern. Golfo de California in cooperation with the. Secretaría .de Marina of México, the Consejo Nacional de Ciencia y Tecnología, the Universidad Autónoma de Baja California and Universidad Nacional Autónoma de México. During our oceanographic analyses of the imagery from the Earth Resources Technology Satellite, we discovered recurring plumes in the water near 114° 1ongitude, 31 o 30' latitude. These p1umes were sometimes as much as ten nautical miles in diameter and appeared to be bodies of clear water, contrasting to the sediment laden turbid water, and thus becoming visible as black spots during the late summer and fall when the waters of the Gulf in that region appeared to be quite heavily sedimented. These plumes were seen on imagery acquired by the Satellite on three different dates: 7 August and 29 and 30 September 1972 (see Figure 1, la). Although these features might be an indication of deep water upwelling from Wagner Basin, they also might arise from large submarine springs. In either case, they are important because they occur offshore of the Gran Deserto where 1) geothermal or fresh water resources are important for the energy or water resources of the, area and 2) knowledge of an area of upwelling is important to the fisheries of the region.