Helium and neon isotopes in the Imnaha Basalt, Columbia River Basalt Group; evidence for a Yellowstone plume source.
Dodson, Allen; Kennedy, B Mack; DePaolo, Donald J (1997) Helium and neon isotopes in the Imnaha Basalt, Columbia River Basalt Group; evidence for a Yellowstone plume source. Earth and Planetary Science Letters. 150; 3-4, Pages 443-451. 1997.
| Authors | Dodson, Allen; Kennedy, B Mack; DePaolo, Donald J |
|---|---|
| Year | 1997 |
| Title | Helium and neon isotopes in the Imnaha Basalt, Columbia River Basalt Group; evidence for a Yellowstone plume source. |
| Source | Earth and Planetary Science Letters. 150; 3-4, Pages 443-451. 1997. |
| Publisher | Elsevier. Amsterdam, Netherlands. 1997. |
| Document type | Serial |
| ISSN | 0012-821X |
| GeoRef | 1997-076868 |
| Keywords | basalts-; Cenozoic-; central-Washington; Columbia-Plateau; Columbia-River-Basalt-Group; flood-basalts; geochemistry-; He-4-He-3; helium-; Idaho-; igneous-rocks; Imnaha-Basalt; isotope-ratios; isotopes-; large-igneous-provinces; lava-flows; mantle-plumes; Miocene-; Ne-22-Ne-20; Ne-22-Ne-21; Neogene-; neon-; noble-gases; stable-isotopes; Tertiary-; United-States; volcanic-rocks; Wanapum-Basalt; Washington-; western-Idaho; Yellowstone-Hot-Spot |
| DOI | 10.1016/S0012-821X(97)00090-3 |
Abstract
Helium, neon, and argon isotopic compositions were measured in two flows of the Columbia River flood basalt. The Imnaha Basalt has a super 3 He/ super 4 He ratio of 11.4 times atmospheric and super 20 Ne/ super 22 Ne and super 21 Ne/ super 22 Ne ratios characteristic of a plume component. The measured super 3 He/ super 4 He is a lower limit, due to possible preferential super 3 He loss and/or addition of radiogenic super 4 He. A Wanapum Basalt flow, erupted approximately 2 Ma later in the waning stages of volcanism, has more MORB-like noble gases. The He, Nd and Sr isotopic compositions of these lavas suggest that the Columbia River basalts were derived from the Yellowstone plume head which contained both high-helium plume material and entrained depleted mantle. As the eruptions progressed the plume component in the melting region was gradually diluted or replaced.
4 samples from this reference
| Sample | Rock name | Major | Trace | Isotope |
|---|---|---|---|---|
| s_CRB 6 | Basalt | yes | yes | |
| s_CRB 14 #1 | Basalt | yes | yes | |
| s_CRB 14 #2 | Basalt | yes | ||
| s_CRB 14 #3 | Basalt | yes |