Santiago Formation, California
| Santiago Formation | |
|---|---|
| Stratigraphic range: Late Eocene-Late Oligocene (Uintan-Duchesnean) | |
| Type | Formation |
| Lithology | |
| Primary | Siltstone, mudstone |
| Other | Sandstone |
| Location | |
| Coordinates | 33°06′N 117°18′W / 33.1°N 117.3°W |
| Approximate paleocoordinates | 33°18′N 104°06′W / 33.3°N 104.1°W |
| Region | Orange & NW San Diego County, California |
| Country |  United States |
  Santiago Formation, California (the United States)  Santiago Formation, California (California) | |
The Santiago Formation is a geologic formation in Orange and northwestern San Diego County, California. The siltstones, mudstones and sandstones of the formation preserve fossils of Walshina esmaraldensis, dating back to the Late Eocene to Late Oligocene periods (Uintan to Duchesnean in the NALMA classification).[1]
Depositional environment
The only paleoenvironmental interpretation based exclusively on specimens from the Santiago Formation is a study of land snails from SDSNH locality 3276 (Member C, Oceanside, San Diego County), which found the distribution of shell sizes and shapes to be consistent with interpretations of subtropical to tropical conditions and paleotemperatures in excess of 25 °C (77 °F).[2]
See also
References
- ^ Kelly Ranch Core at Fossilworks.org
- ^ López Torres et al., 2018, p.5
Bibliography
Further reading
- Prothero, D.R. 2001. Magnetic stratigraphy of the middle-upper Eocene Santiago Formation, Orange and San Diego Counties, California. Guidebook, Pacific Section, Society of Economic Paleontologists and Mineralogists, 91:107-118
Categories:
- Geologic formations of California
- Paleogene California
- Duchesnean
- Uintan
- Priabonian Stage
- Rupelian Stage
- Chattian Stage
- Siltstone formations
- Mudstone formations
- Sandstone formations
- Fluvial deposits
- Fossiliferous stratigraphic units of North America
- Paleontology in California
- Orange County, California
- San Diego County, California