Paleo-oceanographic reconstruction from radiolarian-bearing strata, Baja California and adjacent sections
Middle to upper Miocene radiolarian-bearing strata from Baja California, two adjacent islands (Maria Madre and Maria Cleofas), and the Experimental Mohole were interpreted paleo-oceanographically via radiolarian faunas. Modern distributional and environmental parameters of extant, and paleogeographical and paleoenvironmental reconstruction of extinct radiolarians were used to reconstruct paleotemperatures, paleocirculation, paleo-upwelling, and paleodepth. Results include the recognition that anti-El Nino-like conditions were probably responsible for the pulse of siliceous deposition in Baja California waters during and surrounding the time interval of the Didymocyrtis antepenultima zone (10.1-7.8 Ma). These almost pervasive conditions were interrupted by El Nino conditions around 11-10 Ma and at the top of the Didymocyrtis antepenultima zone (best represented in Tortugas and Arroyo Hondo sections), which might coincide with the 8 and 9 Ma warm events of J.A. Barron and G Keller. Radiolarian evidence from the upper Gulf of California (San Felipe sections) suggests a deep gulf open to the Pacific by 7.8 Ma.
- Research Organization:
- Universidad Nacional Autonomas de Mexico, Mexico City
- OSTI ID:
- 6931298
- Report Number(s):
- CONF-8604187-
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Vol. 70:4; Conference: American Association of Petroleum Geologist Pacific Section convention, Bakersfield, CA, USA, 16 Apr 1986
- Country of Publication:
- United States
- Language:
- English
Similar Records
Paleo-oceanographic circulation as determined from radiolarian populations in Humboldt basin
Reconstruction of California Current at 5, 8, and 10 Ma using radiolarian indicators