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Rak Tuff

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Journal Article
Journal: GSA Bulletin
Published: 01 April 1990
GSA Bulletin (1990) 102 (4): 459–477.
... chron C5C. The uppermost breccias of the Pickhandle Formation are younger than 19.3 m.y. and are likely older than 16.3 m.y., the age of the Rak Tuff that locally caps the Owl Conglomerate Member. The middle member of the Barstow Formation lies stratigraphically above the Owl Conglomerate Member...
Journal Article
Journal: GSA Bulletin
Published: 01 April 1990
GSA Bulletin (1990) 102 (4): 478–493.
... conventional 40 K- 40 Ar and 40 Ar/ 39 Ar single-crystal laser-fusion methods. Multiple analyses on minerals from 5 superposed tuffs yielded the following mean 40 K- 40 Ar ages: Rak Tuff at 16.3 ± 0.3 m.y., Oreodont Tuff at 15.9 ± 0.2 m.y., Dated Tuff at 14.8 ± 0.2 m.y., Hemicyon Tuff at 14.0 ± 0.1 m.y...
Journal Article
Journal: GSA Bulletin
Published: 01 March 2005
GSA Bulletin (2005) 117 (3-4): 276–287.
... the U-Pb systematics of Cenozoic nearsurface deposits including organicrich peat (Rowe et al., 1997), speleothem calcite ( Richards et al., 1998 ), secondary silica ( Neymark et al., 2000 , 2002 ), and coral aragonite ( Getty et al., 2001 ). The Rak Tuff lies at the base of the middle member...
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Figure 2. Schematic stratigraphic sections. All age uncertainties are shown as 2σ. (A) The composite section of Woodburne (1996) compiled from the 40Ar/39Ar and K-Ar ages of smaller dated sections in MacFadden et al. (1990). See Table 1 for description of ages. The Skyline Tuff is in bold because it is an important marker bed for basinwide correlation. The underscored ages for the Oreodont and Valley View Tuffs are considered the most robust because they are 40Ar/39Ar ages of sanidines. (B) Carnivore Canyon section and preferred age of the Hemicyon Tuff (MacFadden et al., 1990). (C) Hell Gate Basin section and preferred age of the Lapilli Sandstone (MacFadden et al., 1990). (D) Steep-side Quarry section from Coon Canyon and preferred age of the Oreodont Tuff (MacFadden et al., 1990). (E) Rainbow Basin section and preferred ages of the Red, Rak, and Dated Tuffs (MacFadden et al., 1990). The (diagenetic) age of the Skyline Tuff is from this section as well (WoldeGabriel et al., 1996). (F) Our measured section from the south limb of the syncline in Owl Canyon. Tufas are exposed on a ridge southwest of Owl Canyon Campground (loc. 1, Fig. 1). This locality is 260 m below the Skyline Tuff and is marked with a star. U-Pb ages for three tufas in italics. (G) The section between Owl and Solomon Canyons is the lithostratigraphic type section for the Barstow Formation and was measured on the north limb of the Barstow syncline (Durrell, 1953). The position of the phytoherm tufa locality (sample OCE-1) on the north limb of the syncline is estimated on this section with a star (loc. 2, Fig. 1). U-Pb tufa age in italics. The stratigraphic position of the final tufa locality (loc. 3, Fig. 1) cannot be estimated on these sections because its current location is covered by Quaternary alluvium
Published: 01 March 2005
) Hell Gate Basin section and preferred age of the Lapilli Sandstone ( MacFadden et al., 1990 ). (D) Steep-side Quarry section from Coon Canyon and preferred age of the Oreodont Tuff ( MacFadden et al., 1990 ). (E) Rainbow Basin section and preferred ages of the Red, Rak, and Dated Tuffs ( MacFadden et
Journal Article
Published: 01 July 2010
Journal of the Geological Society (2010) 167 (4): 817–825.
... provided a basis for geochronology ( Woodburne et al . 1990 ). The base of the ‘Middle' Member is locally defined by the Rak Tuff (16.3 ± 0.3 Ma). The concretions that bear ostracodes with soft tissues occur 62.5 m above the Rak Tuff, and approximately halfway between it and the Oreodont Tuff (15.8 ± 0.3...
FIGURES
Journal Article
Published: 19 February 2016
Journal of the Geological Society (2016) 173 (4): 628–633.
... ), globally correlated to the international Middle Ordovician Darriwilian Stage ( Fortey et al . 2000 ). The Llanfallteg Formation contains siliciclastic and volcaniclastic sediments interbedded with welded lapilli-tuffs. The siliciclastic units comprise massive lenticular or discontinuously laminated...
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Journal Article
Published: 30 January 2018
The Canadian Mineralogist (2018) 56 (1): 15–37.
... subducted beneath the Iranian plate (Stöcklin 1968, Alavi 1994). The regional stratigraphy ( Fig. 1 ) involves: (1) Eocene volcanosedimentary rocks, consisting of intercalated tuff, rhyolite, and limestone; (2) Miocene granitoids (diorite-quartz diorite and granodiorite); and (3) nummulite-bearing Upper...
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Journal Article
Journal: GSA Bulletin
Published: 01 November 2004
GSA Bulletin (2004) 116 (11-12): 1529–1544.
.... The total thickness of the Kada Hadar Member is 20 m along the Ounda Gona and Kada Gona and ∼30 m to the southwest, along the Dana Aouli, Busidima/Asbole drainages. The base of the lower Kada Hadar Member is marked by the Kada Hadar Tuff, 40 Ar/ 39 Ar dated at 3.18 Ma ( Walter, 1994 ). The Kada Hadar Tuff...
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Journal Article
Published: 01 July 2001
Journal of Paleontology (2001) 75 (4): 890–894.
..., containing the Red division fauna of fossil mammals ( Woodburne et al., 1990 ). The middle comprises coarse-grained fluvial and flood deposits from sources to the south and southwest. It contains fossil mammals of the Rak Division Fauna and Green Hills Fauna ( Woodburne et al., 1990 ). The nodules containing...
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Journal Article
Published: 19 June 2015
Geological Magazine (2015) 152 (5): 942–948.
... and welded lapilli-tuffs. Volcaniclastic material likely derives from the rhyolitic arc volcanoes of Eastern Avalonia (Brenchley et al. 2006 ). The Cat's Hole Quarry biota is dominated by graptolites, particularly Didymograptus artus , and includes expansograptids...
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Journal Article
Published: 01 March 1972
Jour. Geol. Soc. India (1972) 13 (1): 39–50.
... metavolcanics within the shear zone such as the chlorite schists and chlorite-biotite-muscovite schists 'Vhich are considered to be related to the Dhanjori lavas (and tuffs). The primary source of uranium is uncertain. It may have been partly derivec through the partial melting of the granitic rocks at depth...
Journal Article
Published: 01 February 2020
Clays and Clay Minerals (2020) 68 (1): 38–49.
... (Rasouli et al. 2012 ; Chen et al. 2018 ). Clinoptilolite, as a natural zeolite, has many advantages for industrial and environmental applications. It is abundant and occurs in high-purity tuffs, it possesses inherent inorganic binders which impart suitable mechanical properties, and it is amenable...
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Journal Article
Journal: GSA Bulletin
Published: 14 October 2019
GSA Bulletin (2020) 132 (5-6): 1066–1082.
... Ma in both Minbu and Chindwin sub-basins. The Paleocene slope environment Paunggyi Formation, which overlies the Kabaw Formation, mainly consists of conglomerate, sandstone, mudstone, and tuff beds in the Minbu sub-basin. In contrast, the Paunggyi Formation in the Chindwin sub-basin is composed...
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Journal Article
Published: 16 June 2023
Journal of Sedimentary Research (2023) 93 (5): 309–326.
... Mtelela et al. (2017) informally divided into a basal member A and overlying member B ( Fig. 2 ). Generally, member A of the LLB unit comprises a basal quartz-rich conglomerate, an intermediate interval of tuffaceous conglomerates, bentonitic mudstones and tuffs, and an upper part of quartz-rich...
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Journal Article
Published: 01 July 2020
Journal of Paleontology (2020) 94 (4): 681–695.
...., 2014 ). The Karazhirik horizon is represented by green-colored various-grained sandstones, siltstones, argillites, shales, bluish-gray ashy tuffs, and lens-like layers of light reef-related limestones of very uneven thickness. The total thickness of the Karazhirik horizon ranges from 500 to 2,400 m...
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Journal Article
Journal: PALAIOS
Published: 30 April 2020
PALAIOS (2020) 35 (4): 175–190.
... dated through biostratigraphy ( Woodburne et al. 1990 ; Pagnac 2009 ), magnetostratigraphy ( MacFadden et al. 1990 ; Woodburne 1996 ), and radiometric dating of airfall tuffs ( Woodburne et al. 1990 ; Miller et al. 2010 ; Miller et al. 2013 ). In the Mud Hills, the Barstow Formation ranges in age...
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Journal Article
Published: 01 November 2021
American Mineralogist (2021) 106 (11): 1852–1859.
... on the moonstone was carried out using a Micromass MM-5400 spectrometry at CUGB. The J factor was estimated by repeated analyses of Fish Canyon Tuff sanidine, with an age of 27.55 ± 0.08 Ma and of the ZBH biotite, a Chinese standard with an age of 133.3 ± 0.24 Ma ( Wang et al. 2011 and references therein), with 1...
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Journal Article
Journal: GSA Bulletin
Published: 08 January 2025
GSA Bulletin (2025) 137 (5-6): 2565–2595.
... reply by highlighting distinct welded tuffs in Otter Point conglomerates—lithologies not present in the Klamath Mountains ( Bourgeois and Dott, 1987 ). Additionally, the reply addresses limitations of using conglomerate clast compositions in regional provenance studies, as well as flaws...
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Journal Article
Journal: GSA Bulletin
Published: 26 April 2022
GSA Bulletin (2023) 135 (1-2): 81–103.
... ; McQuarrie and DeCelles, 2001 ; McQuarrie, 2002 ; Elger et al., 2005 ; Arriagada et al., 2006 ; Ege et al., 2007 ; Barnes et al., 2008 ; Pearson et al., 2013 ; DeCelles et al., 2015a ; Eichelberger et al., 2015 ; Anderson et al., 2017 , 2018 ; Rak et al., 2017 ; Henriquez et al., 2019 , 2020...
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Journal Article
Journal: GSA Bulletin
Published: 01 July 2005
GSA Bulletin (2005) 117 (7-8): 846–864.
... of rhyolitic centers at least 400 m thick: the Insertu formation. The Insertu formation overlies the lower Miocene Birkitu basalt formation. The Insertu formation intrudes and is overlain by further ignimbrite and tuff units of the Shewa Robit formation (Fig. 10) . The western side of Profile F–F...
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