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Research about Imperial Valley

Source-linked reports with geographic coverage including Imperial Valley.

23 records · Page 2Linked to original sources
USGS1975

Earthquakes, active faults, and geothermal areas in the Imperial Valley, California

A dense seismograph network in the Imperial Valley recorded a series of earthquake swarms along the Imperial and Brawley faults and a diffuse pattern of earthquakes along the San Jacinto fault. Two known geothermal areas are closely associated with these earthquake swarms. This seismicity pattern demonstrates that seismic slip is occurring along both the Imperial-Brawley and San Jacinto fault systems.

California↗
USGS1969

A system of regional agricultural land use mapping tested against small scale Apollo 9 color infrared photography of the Imperial Valley (California)

Interpretation results of the small scale ClR photography of the Imperial Valley (California) taken on March 12, 1969 by the Apollo 9 earth orbiting satellite have shown that world wide agricultural land use mapping can be accomplished from satellite ClR imagery if sufficient a priori information is available for the region being mapped. Correlation of results with actual data is encouraging although the accuracy of identification of specific crops from the single image is poor. The poor results can be partly attributed to only one image taken during mid-season when the three major crops were reflecting approximately the same and their ClR image appears to indicate the same crop type. However, some incapacity can be attributed to lack of understanding of the subtle variations of visual and infrared color reflectance of vegetation and surrounding environment. Analysis of integrated color variations of the vegetation and background environment recorded on ClR imagery is discussed. Problems associated with the color variations may be overcome by development of a semi-automatic processing system which considers individual field units or cells. Design criteria for semi-automatic processing system are outlined.

California↗
USGS1964

Barchan-dune movement in Imperial Valley, California

The movement of 47 barchan dunes on the west side of Salton Sea, California, ranged from 325 to 925 feet over the 7 years between 1956 and 1963, an average of 82 feet per year. During the 15 years between 1941 and 1956, the movement of 34 of these dunes ranged between 350 and 1200 feet, an average of 50 feet per year. This difference in average movement during the two intervals is attributed primarily to increased sand supply. Movement ( D ) plotted against height of slip face ( H ) for the Salton dunes fits reasonably well with Finkel's reciprocal curve (1 /D = n + k H ) or with a law of the type D = Pe rH . Factors other than height affect the rate of movement, one of the more important being the state of the dune, whether growing or steady state. Barchan shape, whether fat or slim, may also influence the rate of movement of growing dunes. None of these dunes needs be more than 300 years old.

California↗