Late Miocene and early Pliocene basaltic rocks and their implications for crustal structure, northeastern California and South-central Oregon
McKee, Edwin H; Duffield, Wendell A; Stern, Robert J (1983) Late Miocene and early Pliocene basaltic rocks and their implications for crustal structure, northeastern California and South-central Oregon. Geological Society of America Bulletin, vol.94, no.2, pp.292-304, Feb 1983
| Authors | McKee, Edwin H; Duffield, Wendell A; Stern, Robert J |
|---|---|
| Year | 1983 |
| Title | Late Miocene and early Pliocene basaltic rocks and their implications for crustal structure, northeastern California and South-central Oregon |
| Source | Geological Society of America Bulletin, vol.94, no.2, pp.292-304, Feb 1983 |
| Publisher | Geological Society of America GSA, Boulder, CO, United States USA |
| ISSN | 0016-7606 |
| GeoRef | 1983-025631 |
| Keywords | absolute age; alkaline earth metals; andesites; basalts; California; Cenozoic; crust; dates; Devils Garden lava field; extension tectonics; genesis; geochemistry; geochronology; igneous rocks; isotopes; K/Ar; Klamath County Oregon; Lake County Oregon; lava; lava fields; lower Pliocene; major elements; metals; Miocene; Modoc County California; Neogene; Northern California; olivine tholeiite; Oregon; Pacific Coast; Pliocene; rare earths; rhyolites; Sr-87/Sr-86; stable isotopes; strontium; tectonics; tectonophysics; Tertiary; trace elements; United States; upper Miocene; volcanic features; volcanic rocks; Western U.S. |
| DOI | 10.1130/0016-7606(1983)94<292:LMAEPB>2.0.CO;2 |
Abstract
More than 12,400 km super 2 of Modoc County, California, and Klamath and Lake counties, Oregon, termed the Devils Garden, is underlain by basalt with a total volume of about 850 km super 3 . Olivine tholeiite, characterized by high Al content; low K, Rb, and Cs content; and high K/Rb and K/Cs ratios. Resembles mid-oceanic-ridge basalt but differs in high concentration of Ba and Sr, low K/Ba, and higher super 87 Sr/ super 86 Sr 0.7036-0.7039 ratios. Little or no contamination by sialic crustal material. The basalts originated in the upper mantle and were erupted through crust thinned by tectonic extension behind the Cascade Range volcanic arc.--Modified journal abstract.
33 samples from this reference
| Sample | Rock name | Major | Trace | Isotope |
|---|---|---|---|---|
| Alt 20 | Basalt | |||
| DG 1 | Basalt | |||
| Alt 4 | Basalt | |||
| Alt 18 | Basalt | |||
| Alt 19 | Basalt | yes | yes | yes |
| Alt 6 | Basalt | |||
| Alt 12 | Basalt | |||
| PRM-2-70 | Basalt | |||
| Alt 11 | Basalt | yes | yes | yes |
| Alt 8 | Basalt | |||
| Alt 1 | Basalt | yes | yes | yes |
| Jul-78 | Basalt | |||
| Alt 10 | Basalt | yes | ||
| Alt 9 | Basalt | yes | yes | yes |
| Alt 26 | Basalt | yes | yes | yes |
| Alt 21 | Andesite | |||
| Alt 22 | Andesite | |||
| Alt 13 | Andesite | |||
| Oct-78 | Andesite | |||
| Alt 15 | Andesite | |||
| M-3-106 | Rhyolite | |||
| M-5-2 | Rhyolite | |||
| M-3-35 | Rhyolite | |||
| M-3-34 | Rhyolite | |||
| S-5 | Rhyolite | |||
| M-3-37 | Rhyolite | |||
| M-3-36 | Rhyolite | |||
| M-3-40 | Rhyolite | |||
| M-3-39 | Rhyolite | |||
| KFE-11 | Rhyolite | |||
| 39-78 | Rhyolite | |||
| KFW-6 | Andesite | |||
| Alt 23 | Andesite |