Stable isotope record of late holocene salinity and river discharge in san francisco bay, california

Journal Article · Tue Jan 31 04:00:00 EST 1995 · Earth and Planetary Science Letters

OSTI ID:842261

Ingram, B L ^[1]; Ingle, J C; Conrad, M E

---

1. LBNL Library

Oxygen and carbon isotopic measurements of fossil mollusks from San Francisco Bay are used to derive a record of paleosalinity and paleostreamflow for the past 5,900 years. The delta(18)O and delta(13)C values of river water (-12 parts per thousand and -9 parts per thousand) are markedly different than seawater (0 parts per thousand and 1 parts per thousand), and vary systematically as a function of salinity in the estuary. The data show that annually averaged salinity in the south-central part of the Bay was very close to the modern ''diversion-corrected'' value of 26.8 parts per thousand over the past 2,700 years, and 4 parts per thousand lower than modern between 3,800 and 5,100 yr B.P. Based on those salinities, the average annual river inflow to San Francisco Bay is calculated to have been 1290 m(3)/s over the past 2,400 years, and 1990 m(3)/s between 3,800 and 5,100 yr B.P., 1.8 times greater than the modern ''diversion-corrected'' value of 1100 m(3)/s, assuming a constant bay volume. The inferred river discharge record generally corroborates independent paleohydrologic records in California, including tree-ring, treeline and lake level records.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: DOE
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 842261
• Report Number(s): LBNL--53994
• Journal Information: Earth and Planetary Science Letters, Journal Name: Earth and Planetary Science Letters Journal Issue: 1-4 Vol. 141; ISSN EPSLA2; ISSN 0012-821X
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
58 GEOSCIENCES
CARBON 13
ESTUARIES
FOSSILS
MOLLUSCS
OXYGEN 18
QUATERNARY PERIOD
RIVERS
SALINITY
SAN FRANCISCO BAY
SEAWATER