Chemical analyses used to compute the average chemical composition of rocks and glasses for geochemical units defined in the Yakima Basalt Subgroup, Columbia River Basalt Group, Washington, Oregon, and Idaho

1988 ◽  
Author(s):  
T.L. Wright
Keyword(s):  
Chemical Composition ◽  
Columbia River ◽  
Chemical Analyses ◽  
Average Chemical Composition ◽  
Columbia River Basalt ◽  
Columbia River Basalt Group

Ferro-andesites in the Grande Ronde Basalt: their composition and significance in studies of the origin of the Columbia River Basalt Group

1995 ◽  
Vol 32 (4) ◽  
pp. 424-436 ◽  
Author(s):  
R. StJ. Lambert ◽  
V. E. Chamberlain ◽  
J. G. Holland
Keyword(s):  
Chemical Composition ◽  
Columbia River ◽  
Special Consideration ◽  
Negative Slope ◽  
Magma Chambers ◽  
Uppermost Mantle ◽  
Average Value ◽  
Isotopic Compositions ◽  
Columbia River Basalt ◽  
Columbia River Basalt Group

Flows from the Grande Ronde Basalt of the Columbia River Basalt Group include several with the chemical composition of ferro-andesites. These flows have SiO2 > 55%, MgO < 4%, and also have higher Fe/Mg than the average value for Grande Ronde Basalt. They are also distinctly richer in Cs, Rb, K, Ba, La, Ce, Th, and U than the remainder of the Grande Ronde Basalt flows, and possess small negative Eu anomalies. Their Pb isotopic compositions define a mixing line with a negative slope on a 206Pb/204Pb versus 207Pb/204Pb plot. Their Nd isotopic compositions lie between 143Nd/144Nd = 0.51252 and 0.51264, and their Sr isotopic compositions lie between 87Sr/86Sr = 0.7055 and 0.7060. These values define the enriched end of the Columbia River Basalt Group spectrum on a Sr–Nd epsilon diagram (excluding the Saddle Mountains Basalt). These ferro-andesite flows also form a compositional end member of the Columbia River Basalt Group and are sufficiently distinctive to warrant special consideration. We compare them with lavas from other tholeiitic provinces. Petrogenetically, they can be related to the Grande Ronde Basalt low-Mg basalts by plagioclase fractionation, or by clinopyroxene fractionation in partially melted eclogites. However, the situation may not be that simple, as their unique isotopic compositions are closely related to those of parental mantle materials, perhaps thus requiring separate reservoirs and (or) sources. Extending this argument to other parts of the Columbia River Basalt Group suggests that the origin of these basalts may be in a system of comparatively small magma chambers in the uppermost mantle, frequently replenished from a variety of sources.

Temporally variable crustal contributions to primitive mantle-derived Columbia River Basalt Group magmas

2021 ◽  
pp. 120197
Author(s):  
James M.D. Day ◽  
Kimberley L.R. Nutt ◽  
Brendon Mendenhall ◽  
Bradley J. Peters
Keyword(s):  
Columbia River ◽  
Primitive Mantle ◽  
Columbia River Basalt ◽  
Columbia River Basalt Group

Imnaha Basalt, Columbia River Basalt Group

1984 ◽  
Vol 25 (2) ◽  
pp. 473-500 ◽  
Author(s):  
P. R. HOOPER ◽  
W. D. KLECK ◽  
C. R. KNOWLES ◽  
S. P. REIDEL ◽  
R. L. THIESSEN
Keyword(s):  
Columbia River ◽  
Columbia River Basalt ◽  
Columbia River Basalt Group

scholarly journals Supplemental Material: The Chief Joseph dike swarm of the Columbia River flood basalts, and the legacy data set of William H. Taubeneck

2020 ◽  
Author(s):  
M.C. Morriss ◽  
et al.
Keyword(s):  
Pacific Northwest ◽  
Large Scale ◽  
Columbia River ◽  
Flood Basalts ◽  
Data Set ◽  
Dike Swarm ◽  
Columbia River Basalt ◽  
Legacy Data ◽  
Columbia River Basalt Group ◽  
Columbia River Flood Basalts

Supplemental Plates. Plate S1: Large-scale map of entire extent of Chief Joseph dike swarm. Also incorporates dikes of Ice Harbor, Steens, and Monument swarms. Plate S1 represents the most complete record of dikes related to Columbia River Basalt Group (CRBG) event known. Plate S2: Simplified map of CRBG-related dikes across the inland Pacific Northwest. Dikes are colored by their orientation and dike line density is also shown. Plate S3: Simplified map of CRBG-related dikes across the inland Pacific Northwest.<br>

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