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Research about San Nicolas Island

Source-linked reports with geographic coverage including San Nicolas Island.

23 records · Page 2Linked to original sources

Ground-water data for San Nicolas Island, California, 1989-90

In an effort to gain geohydrologic knowledge and to increase the availability of ground water to the U.S. Navy on San Nicolas Island, nine test wells were drilled by the U.S. Geological Survey in 1989 and one production well was drilled by the U.S. Navy in 1990. One of the nine test wells was dry, five produced less than 10 gallons of water per day, two produced between 20 and 30 gallons per day, and one produced 400 gallons per day. The production well produced about 900 gallons per day. Water samples were collected from eight wells during 1989-90 and analyzed for concentrations of major dissolved inorganic ions and nutrients. Five of the sampled wells were constructed in 1989, one was constructed in 1990, and two were constructed prior to 1989. Data from the study are presented in tables and graphs. Included are geophysical, lithologic, and well-construction data and results obtained from well-pumping tests and from the chemical analysis of water from selected wells.

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Pup production, abundance, and breeding distribution of northern elephant seals at San Nicolas Island, winter 1981

A major breeding colony of northern elephant seals, Mirounga angustirostris , occurs on San Nicolas Island, California. Due to commercial hunting, elephant seals were extinct on San Nicolas Island by the end of the 19th century. Subsequent recovery of the population has been well documented (Table 1). Census data collected since 1949 indicate that the colony has been growing rapidly in numbers after breeding began again in the late 1940s.

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Preliminary report on the geology of San Nicolas Island, California

The U. S. Geological Survey, at the request of the Director of Naval Petroleum Reserves, undertook a geologic investigation of San Nicolas Island, Ventura County California, in the spring of 1955. This preliminary report summarizes present knowledge concerning the general stratigraphy and structure of the island. Additional surface and underwater geologic studies are needed to further differentiate lithologic units within the complexly faulted Eocene sequence and to obtain additional data concerning the northwestward extension of the general anticlinal structure of the island.

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