Modern and ancient mineralization in the Salton Trough Rift

Conference · Wed Jan 01 00:00:00 EST 1992 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:6097636

McKibben, M A ^[1]

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1. Univ. California, Riverside, CA (United States). Dept. Earth Sciences

The Salton Trough of SW North America is an active continental rift, the landward extension of the divergent tectonics of the Gulf of California. Shallow magmatic heat sources, thick porous sediments, tectonic activity and saline lakes interact to yield a variety of Pleistocene to modern hydrothermal systems. The oldest mineralization, the fish Creek evaporite, is a CASO[sub 4] deposit formed by a pre-rift Tertiary marine incursion. 4--5 million years ago the prograding Colorado River delta bisected the Trough, influencing the character of Pliocene and younger hydrothermal activity. The northern part of the Trough became a closed basin filled intermittently by large freshwater lakes. Along the W margin of the rift lies the Modoc hot spring gold deposit. This deposit occurs at the intersection of a range-front growth fault with fossil lake levels, suggesting paleohydrologic control by ancient lakes. Active geothermal systems within the Trough include low-T systems such as Heber and East Mesa, localized along high-angle faults where shallow groundwaters are conductively heated above basement highs. These blind systems have no surface expression and only moderate geophysical anomalies. High-T (> 250 C) active systems occur in sediment filled pull-apart basins developed over spreading center fragments (e.g., Salton Sea, Brawley, Cerro Prieto). These systems exhibit high heat flow, strong gravity and magnetic anomalies, and often have surface manifestations such as Quaternary volcanoes and thermal features. Many contain hot metalliferous brines that have evolved in the saline lake environment of the northern Trough.

• OSTI ID: 6097636
• Report Number(s): CONF-921058-; CODEN: GAAPBC
• Journal Information: Geological Society of America, Abstracts with Programs; (United States), Vol. 24:7; Conference: 1992 annual meeting of the Geological Society of America (GSA), Cincinnati, OH (United States), 26-29 Oct 1992; ISSN 0016-7592
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
CALIFORNIA
GEOLOGIC FORMATIONS
MINERALIZATION
MEXICO
BRAWLEY GEOTHERMAL FIELD
CALCIUM SULFATES
CERRO PRIETO GEOTHERMAL FIELD
COLORADO RIVER
EAST MESA GEOTHERMAL FIELD
GEOLOGIC HISTORY
GEOLOGY
HEBER GEOTHERMAL FIELD
RIFT ZONES
SALTON SEA GEOTHERMAL FIELD
TECTONICS
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
DEVELOPED COUNTRIES
DEVELOPING COUNTRIES
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GEOTHERMAL FIELDS
LATIN AMERICA
NORTH AMERICA
OXYGEN COMPOUNDS
RIVERS
STREAMS
SULFATES
SULFUR COMPOUNDS
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USA
150200* - Geology & Hydrology of Geothermal Systems