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Steens Basalt

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Series: GSA Special Papers
Published: 01 August 2013
DOI: 10.1130/2013.2497(04)
... The Steens Formation, or Steens Basalt, is formally recognized as the oldest lithostratigraphic unit of the Columbia River Basalt Group, with an estimated areal extent and volume of 53,000 km 2 and 31,800 km 3 , respectively. We integrate petrochemical, paleomagnetic, and 40 Ar- 39 Ar age...
Journal Article
Journal: Geosphere
Published: 26 September 2018
Geosphere (2018) 14 (6): 2505–2532.
...N.E. Moore; A.L. Grunder; W.A. Bohrson Abstract The Steens Basalt, southeast Oregon, USA, initiated at 17 Ma as the earliest pulse of the Columbia River Flood Basalt of the northwestern USA. New and existing stratigraphically controlled data reveal temporal changes in lava flow character, and whole...
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Series: GSA Special Papers
Published: 01 August 2013
DOI: 10.1130/2013.2497(03)
... The radiometric dating evidence for the timing and duration of volcanism for the Steens through Wanapum Basalt of the Columbia River Basalt Group is critically reviewed here. K-Ar dates generally underestimate the age of crystallization, though one important exception is detected, where excess...
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Ba versus Cr as a discriminant between lower and upper <b>Steens</b> <b>Basalt</b>, after...
Published: 26 September 2018
Figure 13. Ba versus Cr as a discriminant between lower and upper Steens Basalt, after Camp et al. (2013) . All lower B Steens samples from this study fall within the Lower Steens Tholeiitic field, whereas the lower A Steens and upper Steens samples fall in all three fields.
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Compositions of <b>Steens</b> <b>Basalt</b> (Tbs) and trachyte and trachyandesite lavas o...
Published: 23 June 2017
Figure 3. Compositions of Steens Basalt (Tbs) and trachyte and trachyandesite lavas of McDermitt volcanic field (Tt). Data are compared to all members of Steens Basalt at Steens Mountain, including capping basaltic andesite ( Johnson et al., 1998 ; Camp et al., 2013 ). Steens Basalt
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Ages of <b>Steens</b> <b>Basalt</b> compared to ages for High Rock caldera complex (HRCC)...
Published: 01 February 2016
Figure 26. Ages of Steens Basalt compared to ages for High Rock caldera complex (HRCC) rhyolites and postcaldera mafic and intermediate lavas. The lower panel shows individual ages and reported errors (2σ) recalculated using λ = 5.543e –10 yr –1 ( Steiger and Jäger, 1977 ) and referenced
Journal Article
Journal: GSA Bulletin
Published: 01 January 2003
GSA Bulletin (2003) 115 (1): 105–128.
...Victor E. Camp; Martin E. Ross; William E. Hanson Abstract The middle and south forks of the Malheur River provide a unique mapping corridor connecting two flood-basalt successions—Steens basalt to the south and the basalt of Malheur Gorge to the north. Each contains chemically defined subtypes...
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Journal Article
Journal: GSA Bulletin
Published: 01 January 2002
GSA Bulletin (2002) 114 (1): 43–50.
...P.R. Hooper; G.B. Binger; K.R. Lees Abstract Stratigraphic and chemical correlations of Tertiary volcanic units in eastern Oregon confirm that the Steens Basalt represents the earliest eruptions of the Columbia River flood-basalt province. Field correlations are supported by major and trace element...
FIGURES | View All (5)
Journal Article
Journal: GSA Bulletin
Published: 23 June 2017
GSA Bulletin (2017) 129 (9-10): 1027–1051.
...Figure 3. Compositions of Steens Basalt (Tbs) and trachyte and trachyandesite lavas of McDermitt volcanic field (Tt). Data are compared to all members of Steens Basalt at Steens Mountain, including capping basaltic andesite ( Johnson et al., 1998 ; Camp et al., 2013 ). Steens Basalt...
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Series: GSA Special Papers
Published: 07 February 2019
DOI: 10.1130/2018.2538(01)
EISBN: 9780813795386
... features include: Lewiston Basin (LB), Troy Basin (TrB), Devils Canyon (DC), Harney Basin (HB), Steens Mountain (SM), Dog Mountain (DM), and Portland Basin (PB). Figure 3. Compositional variation in the Umatilla Member, Saddle Mountains Basalt. Pattern shows the extent of the Umatilla Member...
FIGURES | View All (9)
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Ternary plot comparing High Rock caldera complex (HRCC) mafic lavas with St...
Published: 01 February 2016
Figure 14. Ternary plot comparing High Rock caldera complex (HRCC) mafic lavas with Steens Basalt. Postcaldera lavas (Mm) are more alkalic and more evolved than most Steens Basalt. Postcaldera basalts MC434 and MC342 plot in the field for Steens Basalt, suggesting they represent Steens Basalt
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Comparison of the composition of mafic lavas in and around High Rock calder...
Published: 01 February 2016
Figure 13. Comparison of the composition of mafic lavas in and around High Rock caldera complex (HRCC) to the Steens Basalt and other Miocene basalts of northern Nevada. Postcaldera mafic lavas (Mm) have lower concentrations of high field strength elements than Steens Basalt. The two exceptions
Journal Article
Journal: Geosphere
Published: 17 July 2017
Geosphere (2017) 13 (4): 1066–1112.
... two episodes of Eocene intermediate volcanism at 47 and 39 Ma and major middle Miocene volcanism that led continuously to caldera formation. Eruption of the Steens Basalt, the oldest Miocene activity, began before 16.69 Ma. Exclusively mafic magmas erupted initially. Rhyolite lavas erupted as early...
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Figure 12. Total alkali vs. silica diagram ( LeBas et al., 1986 ) showing c...
Published: 01 January 2003
Figure 12. Total alkali vs. silica diagram ( LeBas et al., 1986 ) showing comparisons between tholeiitic rocks in the map area and those both north and south of the map area. (A) Steens basalt from the Steens Mountain section of Johnson et al. (1998a) . Analyses collected in the lower one-third
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Chemistry of northern McDermitt volcanic field mafic lavas. Tule Rims trach...
Published: 23 June 2017
caldera complex ( Coble and Mahood, 2016 ). Basalts from both volcanic centers have higher large ion lithophile to high field strength element ratios compared to Steens Basalt. Steens Basalt field follows definition of Steens Basalt by Camp et al. (2013) , encompassing lower Steens, upper Steens
Journal Article
Journal: Geosphere
Published: 01 February 2016
Geosphere (2016) 12 (1): 58–113.
...Figure 26. Ages of Steens Basalt compared to ages for High Rock caldera complex (HRCC) rhyolites and postcaldera mafic and intermediate lavas. The lower panel shows individual ages and reported errors (2σ) recalculated using λ = 5.543e –10 yr –1 ( Steiger and Jäger, 1977 ) and referenced...
FIGURES | View All (28)
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Geochemical data from Middle Miocene (16–14 Ma) Warner Range volcanic rocks...
Published: 01 June 2011
Figure 13. Geochemical data from Middle Miocene (16–14 Ma) Warner Range volcanic rocks (this study) plotted with analyses from the Steens Basalt ( Johnson et al., 1998 ). Warner Range volcanic rocks are prominently depleted in Nb, Ta, Zr, and Ti relative to Steens Basalt, with consistently lower
Journal Article
Journal: Economic Geology
Published: 01 January 2006
Economic Geology (2006) 101 (1): 33–57.
... that are high in Cu, Ni, and Zn and that appear to be related to the Steens Basalt. The other important factor is related to hydrothermal precious metal mineralization and is characterized by Sb, Ag, As, Pb, Au, and Zn. The map of the distribution of this factor is similar in appearance to the one for arsenic...
FIGURES | View All (15)
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Total alkalies versus silica (TAS) classification of rocks in and adjacent ...
Published: 01 February 2016
on the TAS diagram. Data for upper and lower Steens Basalt are from Johnson et al. (1998) ; Steens Basalt in areas around HRCC (shown as local Steens Basalt) are from Hart et al. (1989) , Colgan et al. (2006) , and this study.
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Figure 5. Stratigraphy and map distribution of main Columbia River <b>Basalt</b> G...
Published: 01 June 2008
as depicted in the cross-sectional diagrams of Figure 7 . Paleo-magnetic units R0–N2 correspond with sequential reverse and normal paleomagnetic intervals during the main-phase eruptions. The terms lower Steens and upper Steens Basalts are defined in Hooper et al. (2002) and Camp et al. (2003) . Imnaha