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J.A. Barron

Publications and source records attributed to J.A. Barron.

39 records · Page 3Linked to original sources
USGS1977

Descriptions of pre-Quaternary samples, R/V Ellen B. Scripps, September 1976, Patton Ridge to Blake Knolls, California continental borderland

A sampling cruise under the joint sponsorship of Scripps Institution of Oceanography and the U. S. Geological Survey was completed in early October 1976 as part of the Survey's resource and environmental studies on the California Continental Borderland. J. K. Crouch was Chief Scientist for the cruise aboard R/V ELLEN B. SCRIPPS. Samples were taken entirely by means of dart corers, and navigation for sample sites was done using the LORAC system supported by shipboard radar. Depths were corrected for sound-velocity variations in water (Matthews, 1939). In some instances, recorded depths in the table may not match bathymetric contours on published maps because of imprecise navigation on pre-1940 surveys.

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USGS1976

Revised Miocene and Pliocene diatom biostratigraphy of Upper Newport Bay, Newport Beach, California

North Pacific diatom zones XXIII through IX of Schrader are recognizable in the middle Miocene to lower Pliocene stratigraphic section exposed around Upper Newport Bay in Newport Beach, California. Correlation with DSDP Site 173 and other stratigraphic sections in California allows the selection of diatom datums that are the most reliable for long-distance correlation. Individual diatom datums are proposed as markers for North Pacific diatom zones XXIII through IX. Correlations with DSDP Site 173 reveal a hiatus in the lower part of Core 15 that corresponds with a distinct lithologic and floral change in the core. Preliminary silicoflagellate data for the Upper Newport Bay stratigraphic section supports the diatom correlations. Correlation with calcareous nannofossil, radiolarian, and silicoflagellate zones at Upper Newport Bay and at DSDP Site 173 suggests that the boundary between North Pacific diatom zones XVII and XVI approximates the middle Miocene/upper Miocene boundary. The Miocene/Pliocene boundary is estimated to be in North Pacific diatom zone X. One new stratigraphically useful diatom species is described, Lithodesmium reynoldsii .

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