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Geology topics

Elliott C. Spiker

Publications and source records attributed to Elliott C. Spiker.

6 recordsLinked to original sources
USGS2016

The behavior of 14 C and 13 C in estuarine water: Effects of In situ CO 2 production and atmospheric exchange

The effects of nonconservative sources (inputs) and sinks (outputs) of carbon are indicated by the behavior of Δ 14 C and δ 13 C of the total dissolved inorganic carbon (ΣCO 2 ) in San Francisco Bay and Chesapeake Bay. Isotopic distributions and model calculations indicate that in North San Francisco Bay the net CO 2 flux to the atmosphere and carbon utilization in the water column are balanced by benthic production. Municipal waste appears to be a dominant source in South San Francisco Bav. In Chesapeake Bay, atmospheric exchange has increased the Δ 14 C and δ 13 C in the surface water. Decomposition of organic matter in the water column is indicated to be the dominant source of excess ΣCO 2 in the deep water.

Radiocarbon↗
USGS1984

Carbon isotope fractionation of sapropelic organic matter during early diagenesis

Study of an algal, sapropelic sediment from Mangrove Lake, Bermuda shows that the mass balance of carbon and stable carbon isotopes in the major organic constituents is accounted for by a relatively straightforward model of selective preservation during diagenesis. The loss of 13 C-enriched carbohydrates is the principal factor controlling the intermolecular mass balance of 13 C in the sapropel. Results indicate that labile components are decomposed leaving as a residual concentrate in the sediment an insoluble humic substance that may be an original biochemical component of algae and associated bacteria. An overall decrease of up to about 4‰ in the δ 13 C values of the organic matter is observed as a result of early diagenesis.

Mangrove Lake↗
USGS1980

Upper Wisconsinan till recovered on the continental shelf southeast of New England

Basal till was identified in two sediment cores collected about 69 kilometers southeast of Nantucket Island on the east and west sides of Great South Channel. These are the first samples of till collected on the outer continental shelf off the northeastern United States. The carbon-14 age of the total organic carbon in the tills provides a "no older than" age of about 20,000 years before present and suggests that the tills were deposited during the late Wisconsinan glaciation. This conclusion is in support of the hypothesis of an extensive Laurentide ice sheet that extended to the northern side of Georges Bank.

Science↗
USGS1979

Water and sediment measurements in San Francisco Bay, California

Water samples collected in San Francisco Bay, the Gulf of the Farallones, and the delta of the Sacramento and San Joaquin rivers were analyzed for salinity, temperature, partial pressure of carbon dioxide (pCO 2 ), chlorophyll a, alkalinity, particulate organic carbon (POC), and the stable carbon isotope ratio ( δ 13 C) of the POC and total CO 2 . Water sampling occurred between January 1976 and March 1977. Bottom sediments for total organic carbon isotopic analyses ( δ 13 C(TOC)) were collected during August 1973. Numerical values are tabulated, sampling locations are identified, and the analytical methods are briefly described.

California↗