John N Aleinikoff
John Aleinikoff is a Scientist Emeritus with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 109
Petrology and U-PB geochronology of the Robertson River Igneous Suite, Blue Ridge province, Virginia - Evidence for multistage magmatism associated witn an early episode of Laurentian rifting Petrology and U-PB geochronology of the Robertson River Igneous Suite, Blue Ridge province, Virginia - Evidence for multistage magmatism associated witn an early episode of Laurentian rifting
The Late Neoproterozoic (735-702 Ma) Robertson River Igneous Suite includes at least eight plutons ranging in composition from syenogranite to alkali feldspar granite to alkali feldspar syenite. These plutons intruded Mesoproterozoic (1.2-1.0 Ga) gneissic basement of the Blue Ridge anticlinorium in northern and central Virginia during an early episode of Laurentian rifting. Robertson...
Authors
Richard P. Tollo, John N. Aleinikoff
Metamorphic and structural history of continental crust at a Mesozoic collisional margin, the Ruby terrane, central Alaska Metamorphic and structural history of continental crust at a Mesozoic collisional margin, the Ruby terrane, central Alaska
The Ruby terrane is an elongate fragment of continental crustal rocks that is structurally overlain by thrust slices of oceanic crust. Our results from the Kokrines Hills, in the south‐central part of the Ruby terrane, demonstrate that the low‐angle schistose fabric formed under high‐P/low‐T conditions, at peak conditions of 10.8‐13.2 kbar and 425‐550° C, consistent with the rare...
Authors
S. M. Roeske, Cynthia Dusel-Bacon, John N. Aleinikoff, L.W. Snee, Marvin A. Lanphere
U-Pb ages of metarhyolites of the Catoctin and Mount Rogers formations, central and southern Appalachians: Evidence for two pulses of Iapetan rifting U-Pb ages of metarhyolites of the Catoctin and Mount Rogers formations, central and southern Appalachians: Evidence for two pulses of Iapetan rifting
No abstract available.
Authors
John N. Aleinikoff, Robert E. Zartman, Marianne Walter, Douglas W. Rankin, Peter T. Lyttle, William C. Burton
Isotopic tracers of gold deposition in Paleozoic limestones, southern Nevada Isotopic tracers of gold deposition in Paleozoic limestones, southern Nevada
Strontium isotopic analyses of barren and mineralized Paleozoic carbonate rocks show that hydrothermal fluids added radiogenic strontium (87Sr) to the mineralized zones. At Bare Mountain, samples collected from mineralized areas have ??87Srt values (per mil deviation from primary marine values) ranging from +3.0 to +23.0 (mean of this log-normal distribution is +7.0), whereas...
Authors
Z. E. Peterman, B.L. Widmann, B.D. Marshall, J. N. Aleinikoff, K. Futa, S. A. Mahan
Devonian volcanogenic massive sulfide deposits and occurrences, southern Yukon-Tanana Terrace, eastern Alaska Range, Alaska Devonian volcanogenic massive sulfide deposits and occurrences, southern Yukon-Tanana Terrace, eastern Alaska Range, Alaska
A belt of volcanogenic massive sulfide deposits extends for over 150 km along the southern margin of the Yukon-Tanana terrane of the eastern Alaska Range. Located north of the Denali fault, the Yukon-Tanana terrane forms a major basement unit in east-central Alaska. The volcanogenic massive sulfide deposits are primarily in the Jarvis Creek Glacier subterrane, one of the highest...
Authors
I. M. Lange, W. J. Nokleberg, S.R. Newkirk, J. N. Aleinikoff, S. E. Church, H.R. Krouse
Do ages of authigenic K-feldspar date the formation of Mississippi valley-type Pb-Zn deposits, central and southeastern United States?: Pb isotopic evidence Do ages of authigenic K-feldspar date the formation of Mississippi valley-type Pb-Zn deposits, central and southeastern United States?: Pb isotopic evidence
Pb concentrations and isotopic compositions have been determined for authigenic over-growths and detrital cores of K-feldspar from Cambrian sedimentary rocks in Texas, Tennessee, and Pennsylvania (referred to as group 1) and southeastern Missouri (referred to as group 2). Overgrowths and cores were separated by abrasion and analyzed separately. In three group 1 samples, cores have Pb...
Authors
J. N. Aleinikoff, M. Walters, Michael J. Kunk, P.P. Hearn
Science and Products
Filter Total Items: 109
Petrology and U-PB geochronology of the Robertson River Igneous Suite, Blue Ridge province, Virginia - Evidence for multistage magmatism associated witn an early episode of Laurentian rifting Petrology and U-PB geochronology of the Robertson River Igneous Suite, Blue Ridge province, Virginia - Evidence for multistage magmatism associated witn an early episode of Laurentian rifting
The Late Neoproterozoic (735-702 Ma) Robertson River Igneous Suite includes at least eight plutons ranging in composition from syenogranite to alkali feldspar granite to alkali feldspar syenite. These plutons intruded Mesoproterozoic (1.2-1.0 Ga) gneissic basement of the Blue Ridge anticlinorium in northern and central Virginia during an early episode of Laurentian rifting. Robertson...
Authors
Richard P. Tollo, John N. Aleinikoff
Metamorphic and structural history of continental crust at a Mesozoic collisional margin, the Ruby terrane, central Alaska Metamorphic and structural history of continental crust at a Mesozoic collisional margin, the Ruby terrane, central Alaska
The Ruby terrane is an elongate fragment of continental crustal rocks that is structurally overlain by thrust slices of oceanic crust. Our results from the Kokrines Hills, in the south‐central part of the Ruby terrane, demonstrate that the low‐angle schistose fabric formed under high‐P/low‐T conditions, at peak conditions of 10.8‐13.2 kbar and 425‐550° C, consistent with the rare...
Authors
S. M. Roeske, Cynthia Dusel-Bacon, John N. Aleinikoff, L.W. Snee, Marvin A. Lanphere
U-Pb ages of metarhyolites of the Catoctin and Mount Rogers formations, central and southern Appalachians: Evidence for two pulses of Iapetan rifting U-Pb ages of metarhyolites of the Catoctin and Mount Rogers formations, central and southern Appalachians: Evidence for two pulses of Iapetan rifting
No abstract available.
Authors
John N. Aleinikoff, Robert E. Zartman, Marianne Walter, Douglas W. Rankin, Peter T. Lyttle, William C. Burton
Isotopic tracers of gold deposition in Paleozoic limestones, southern Nevada Isotopic tracers of gold deposition in Paleozoic limestones, southern Nevada
Strontium isotopic analyses of barren and mineralized Paleozoic carbonate rocks show that hydrothermal fluids added radiogenic strontium (87Sr) to the mineralized zones. At Bare Mountain, samples collected from mineralized areas have ??87Srt values (per mil deviation from primary marine values) ranging from +3.0 to +23.0 (mean of this log-normal distribution is +7.0), whereas...
Authors
Z. E. Peterman, B.L. Widmann, B.D. Marshall, J. N. Aleinikoff, K. Futa, S. A. Mahan
Devonian volcanogenic massive sulfide deposits and occurrences, southern Yukon-Tanana Terrace, eastern Alaska Range, Alaska Devonian volcanogenic massive sulfide deposits and occurrences, southern Yukon-Tanana Terrace, eastern Alaska Range, Alaska
A belt of volcanogenic massive sulfide deposits extends for over 150 km along the southern margin of the Yukon-Tanana terrane of the eastern Alaska Range. Located north of the Denali fault, the Yukon-Tanana terrane forms a major basement unit in east-central Alaska. The volcanogenic massive sulfide deposits are primarily in the Jarvis Creek Glacier subterrane, one of the highest...
Authors
I. M. Lange, W. J. Nokleberg, S.R. Newkirk, J. N. Aleinikoff, S. E. Church, H.R. Krouse
Do ages of authigenic K-feldspar date the formation of Mississippi valley-type Pb-Zn deposits, central and southeastern United States?: Pb isotopic evidence Do ages of authigenic K-feldspar date the formation of Mississippi valley-type Pb-Zn deposits, central and southeastern United States?: Pb isotopic evidence
Pb concentrations and isotopic compositions have been determined for authigenic over-growths and detrital cores of K-feldspar from Cambrian sedimentary rocks in Texas, Tennessee, and Pennsylvania (referred to as group 1) and southeastern Missouri (referred to as group 2). Overgrowths and cores were separated by abrasion and analyzed separately. In three group 1 samples, cores have Pb...
Authors
J. N. Aleinikoff, M. Walters, Michael J. Kunk, P.P. Hearn