The stratigraphic significance of fission-track ages on volcanic ashes in the marine Late Cenozoic of Southern California

Fission-track and K-Ar ages of natural glasses

“…This result is in direct conflict with the findings of Boellstorff and Steineck (1975), who concluded that a reduction in diameter of the fossil tracks does not affect the age, and that annealing probably does not take place at ambient temperatures.…”

Chemical analyses, correlations, and ages of upper Pliocene and Pleistocene ash layers of east-central and Southern California

“…1, 2; Izett and others, 1974) and an age of about 1.2 ±0.3 m.y. obtained by the fission-track method on glass (Boellstorff and Steineck, 1975) are most compatible with other available ages, and stratigraphic and biostratigraphic information.…”

Neogene biostratigraphy of selected areas in the California Coast Ranges

“…This difficulty has been overcome in part through correlation of paleontologically identifiable paleoclimatic events within the California Current province (Ingle, 1977) along with important fission track ages within the Balcom Canyon section (Boellstorff and Steineck, 1976) and recent identification of major paleomagnetic events within Pliocene-Pleistocene strata of the South Mountain area (Blackie and Yeats, 1977). by Izett et al (1974) and Boellstorff and Steineck (1975).…”

“…old (Izett, Naeser, and Obradovich, 1974;Boellstorff and Steineck, 1975). Enclosing strata contain well-preserved upper bathyal Wheelerian benthic foraminiferal assemblages indicative of deposition on the shoaling Pliocene-Pleistocene slope.…”

“…In short, the Ventura Basin constitutes a premier area in which to study the character of lithofacies and biofacies changes in an ecologically, climatically, and tectonically dynamic Note that paleobathymetry is plotted in terms of maximum stratigraphic thickness of each formation and alternately in terms of estimated duration of each unit in time following the correlations presented by Ingle (in press). Chronostratigraphy incorporates fission track ages reported by Izett, Naeser, and Obradovich (1974) and Boellstorff and Steineck (1975) and the paleomagnetic data of Blackie and Yeats (1976). Estimated paleobathymetry is based on biofacies analysis of benthonic Foraminifera reported from these units by Natland (1933Natland ( , 1952Natland ( , 1957, Kuenen (1951), and.…”