Jim Budahn
Jim Budahn is a Scientist Emeritus with the Geosciences and Environmental Change Science Center
Science and Products
Filter Total Items: 61
Rare earth element contents and multiple mantle sources of the transform-related Mount Edgecumbe basalts, southeastern Alaska Rare earth element contents and multiple mantle sources of the transform-related Mount Edgecumbe basalts, southeastern Alaska
Pleistocene basalt of the Mount Edgecumbe volcanic field (MEF) is subdivided into a plagioclase type and an olivine type. Olivine basalt crops out farther inboard from the nearby Fairweather transform than plagioclase basalt. Th/La ratios of plagioclase basalt are similar to those of mid-ocean-ridge basalt (MORB), whereas those of olivine basalt are of continental affinity. The olivine...
Authors
J.R. Riehle, J. R. Budahn, M. A. Lanphere, D. A. Brew
Actualistic models of mantle metasomatism documented in a composite xenolith from Dish Hill, California Actualistic models of mantle metasomatism documented in a composite xenolith from Dish Hill, California
Major and trace-element whole rock and mineral variations in composite hornblendite-peridotite xenolith Ba-2-1, from Dish Hill, CA, are due to a single event of metasomatism in the mantle. The hornblendite is the crystallized selvage of a dike conduit charged with incompatible-element-enriched hydrous mafic magma. The magma infiltrated the refractory peridotite wallrock, reacted with its
Authors
J. E. Nielson, J. R. Budahn, D.M. Unruh, H. G. Wilshire
Back-arc with frontal-arc component origin of Triassic Karmutsen basalt, British Columbia, Canada Back-arc with frontal-arc component origin of Triassic Karmutsen basalt, British Columbia, Canada
The largely basaltic, ???4.5-6.2-km-thick, Middle to Upper Triassic Karmutsen Formation is a prominent part of the Wrangellian sequence. Twelve analyses of major and minor elements of representative samples of pillowed and massive basalt flows and sills from Queen Charlotte and Vancouver Islands are ferrotholeiites that show a range of 10.2-3.8% MgO (as normalized, H2O- and CO2-free) and...
Authors
F. Barker, Brown A. Sutherland, J. R. Budahn, George Plafker
Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range
The Angayucham Mountains (north margin of the Yukon-Koyukuk province) are made up of an imbricate stack of four to eight east-west trending, steeply dipping, fault slabs composed of Paleozoic (Devonian to Mississippean), Middle to Late Triassic, and Early Jurassic oceanic upper crustal rocks (pillow basalt, subordinate diabase, basaltic tuff, and radiolarian chert). Field relations and...
Authors
J.S. Pallister, J. R. Budahn, B.L. Murchey
Ocean plateau-seamount origin of basaltic rocks, Angayucham terrane, central Alaska Ocean plateau-seamount origin of basaltic rocks, Angayucham terrane, central Alaska
The Angayucham terrane of north-central Alaska (immediately S of the Brooks Range) is a large (ca. 500 km E-W), allochthonous complex of Devonian to Lower Jurassic pillow basalt, diabase sills, gabbro plutons, and chert. The mafic rocks are transitional normal-to-enriched, mid-ocean-ridge (MORB) type tholeiites (TiO2 1.2-3.4%, Nb 7-23 ppm, Ta 0.24-1.08 ppm, Zr 69-214 ppm, and light REE's...
Authors
F. Barker, D. L. Jones, J. R. Budahn, P.J. Coney
Evidence for equilibrium conditions during the partitioning of nickel between olivine and komatiite liquids. Evidence for equilibrium conditions during the partitioning of nickel between olivine and komatiite liquids.
Olivine-liquid partition coefficients for Ni(DNi), calculated from Ni vs MgO abundance variations in komatiite series basalts, compare favourably with experimentally determined values, if Ni variations in olivine-controlled basalts can be modelled with an equation that assumes equilibrium between the entire olivine crystal and its coexisting liquid.-J.A.Z.
Authors
J. R. Budahn
Science and Products
Filter Total Items: 61
Rare earth element contents and multiple mantle sources of the transform-related Mount Edgecumbe basalts, southeastern Alaska Rare earth element contents and multiple mantle sources of the transform-related Mount Edgecumbe basalts, southeastern Alaska
Pleistocene basalt of the Mount Edgecumbe volcanic field (MEF) is subdivided into a plagioclase type and an olivine type. Olivine basalt crops out farther inboard from the nearby Fairweather transform than plagioclase basalt. Th/La ratios of plagioclase basalt are similar to those of mid-ocean-ridge basalt (MORB), whereas those of olivine basalt are of continental affinity. The olivine...
Authors
J.R. Riehle, J. R. Budahn, M. A. Lanphere, D. A. Brew
Actualistic models of mantle metasomatism documented in a composite xenolith from Dish Hill, California Actualistic models of mantle metasomatism documented in a composite xenolith from Dish Hill, California
Major and trace-element whole rock and mineral variations in composite hornblendite-peridotite xenolith Ba-2-1, from Dish Hill, CA, are due to a single event of metasomatism in the mantle. The hornblendite is the crystallized selvage of a dike conduit charged with incompatible-element-enriched hydrous mafic magma. The magma infiltrated the refractory peridotite wallrock, reacted with its
Authors
J. E. Nielson, J. R. Budahn, D.M. Unruh, H. G. Wilshire
Back-arc with frontal-arc component origin of Triassic Karmutsen basalt, British Columbia, Canada Back-arc with frontal-arc component origin of Triassic Karmutsen basalt, British Columbia, Canada
The largely basaltic, ???4.5-6.2-km-thick, Middle to Upper Triassic Karmutsen Formation is a prominent part of the Wrangellian sequence. Twelve analyses of major and minor elements of representative samples of pillowed and massive basalt flows and sills from Queen Charlotte and Vancouver Islands are ferrotholeiites that show a range of 10.2-3.8% MgO (as normalized, H2O- and CO2-free) and...
Authors
F. Barker, Brown A. Sutherland, J. R. Budahn, George Plafker
Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range
The Angayucham Mountains (north margin of the Yukon-Koyukuk province) are made up of an imbricate stack of four to eight east-west trending, steeply dipping, fault slabs composed of Paleozoic (Devonian to Mississippean), Middle to Late Triassic, and Early Jurassic oceanic upper crustal rocks (pillow basalt, subordinate diabase, basaltic tuff, and radiolarian chert). Field relations and...
Authors
J.S. Pallister, J. R. Budahn, B.L. Murchey
Ocean plateau-seamount origin of basaltic rocks, Angayucham terrane, central Alaska Ocean plateau-seamount origin of basaltic rocks, Angayucham terrane, central Alaska
The Angayucham terrane of north-central Alaska (immediately S of the Brooks Range) is a large (ca. 500 km E-W), allochthonous complex of Devonian to Lower Jurassic pillow basalt, diabase sills, gabbro plutons, and chert. The mafic rocks are transitional normal-to-enriched, mid-ocean-ridge (MORB) type tholeiites (TiO2 1.2-3.4%, Nb 7-23 ppm, Ta 0.24-1.08 ppm, Zr 69-214 ppm, and light REE's...
Authors
F. Barker, D. L. Jones, J. R. Budahn, P.J. Coney
Evidence for equilibrium conditions during the partitioning of nickel between olivine and komatiite liquids. Evidence for equilibrium conditions during the partitioning of nickel between olivine and komatiite liquids.
Olivine-liquid partition coefficients for Ni(DNi), calculated from Ni vs MgO abundance variations in komatiite series basalts, compare favourably with experimentally determined values, if Ni variations in olivine-controlled basalts can be modelled with an equation that assumes equilibrium between the entire olivine crystal and its coexisting liquid.-J.A.Z.
Authors
J. R. Budahn