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The AAPG/Datapages Combined Publications Database

AAPG Bulletin


Volume: 49 (1965)

Issue: 10. (October)

First Page: 1768

Last Page: 1768

Title: Some Paleoecologic Aspects of Recent Ecology of Mugu Lagoon, California: ABSTRACT

Author(s): John E. Warme

Article Type: Meeting abstract


Shallow-water marine research is being conducted at the Pacific Missile Range Headquarters of the U. S. Navy, Point Mugu, California. This area was chosen because of its relatively natural state, ecologic variation, and large populations of invertebrates that may be preserved in the geologic record. Consent and aid for this project has been given by the Navy.

Mugu Lagoon contains varied sediments exhibiting abrupt vertical and lateral changes in texture, color, bedding, and organic content. Hydrography is tidally controlled. Grain-size generally decreases with distance from the lagoon inlet. A typical column of sediment 8.8 ft. thick (the range of intertidal sedimentation within the lagoon) grades from nearshore sands at the base through channel and tide-flat deposits to peaty and fine-grained salt-marsh soils. Most of the plants and animals present are endemic to coastal lagoons, and their specificity for given habitats within this area is being investigated. Tidal level and substrate type exercise strong control on distribution and density of the benthos.

Of paleoecologic interest is the extent to which environment is impressed on the sediments. Macro-organisms such as pelecypods, gastropods, burrowing crustaceans, and worms tend to obliterate bedding and construct diverse biogenic structures. Populations of living shelled invertebrates are being surveyed and compared with shell remains from the same quadrants to show effective transportation of shells before burial. Microfaunal assemblages characteristic of habitats within this area also are being studied.

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Copyright 1997 American Association of Petroleum Geologists