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Erwin Formation

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Journal Article
Published: 01 January 1990
Journal of Sedimentary Research (1990) 60 (1): 84–100.
...Edward L. Simpson; Kenneth A. Eriksson Abstract Occurrence of both the Hampton and Erwin Formations within a number of thrust sheets provides an oblique cross section of the paleoslope permitting an across-strike reconstruction of the Early Cambrian passive margin. Five environmental settings...
Journal Article
Journal: GSA Bulletin
Published: 01 January 1989
GSA Bulletin (1989) 101 (1): 42–54.
...-flow deposits at the base of the Hampton Formation. Deepening may have been enhanced by continued movement along listric faults throughout the incipient phase of passive-margin development. Most of the Hampton Formation and the overlying Erwin Formation and Shady Dolomite record pro-gradation...
Journal Article
Journal: GSA Bulletin
Published: 01 May 1959
GSA Bulletin (1959) 70 (5): 619–636.
... by the Buffalo Mountain thrust sheet, which has been separated by two minor thrust faults into three imbricate thrust blocks. Cambrian and Precambrian (?) rocks in the Buffalo Mountain thrust sheet consist of the Unicoi, Hampton, and Erwin formations (Chilhowee group) and the Shady dolomite. Younger, Cambrian...
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(A) In the Shady Dolomite in the Iron Mountain location of the Mountain City window of Tennessee, interbedded Fe- and Mn oxide deposits are found in the fractured axes of existing folds. (B) Example of the interbedded Mn oxides and Fe oxyhydroxides showing porous and laminated morphologies (sample JC-10). (C) In the Erwin Formation, Mn and Fe oxides are deposited along existing bedding planes in quartzite. (D) Mn oxides in the Erwin Formation are frequently deposited as dendrites up to 1 mm in diameter (sample SH-1).
Published: 11 May 2017
morphologies (sample JC-10). (C) In the Erwin Formation, Mn and Fe oxides are deposited along existing bedding planes in quartzite. (D) Mn oxides in the Erwin Formation are frequently deposited as dendrites up to 1 mm in diameter (sample SH-1).
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Backscattered scanning electron microscope (SEM) photomicrographs from breccia fills and bedding planes of the Shouns Prospect and Erwin Formation showing (A) the surface of Erwin Formation sample SH-1 (hand sample shown in Fig. 5D) with Mn oxide dendrites surrounded by a rind of secondary quartz (gray) with imprints of gas bubbles (white arrows); (B) a porous network of nanometer-scale needles of a solid solution of cryptomelane-hollandite that forms the dendrite shown in A; (C) drusy coating of cryptomelane-hollandite Mn oxides on the interior surfaces of quartz geodes in Shouns Prospect sample JC-7A (hand sample shown in Fig. 4D), forming a network of interconnected strings of Mn oxide needles; (D) chains of Mn oxide needles showing acicular radiation from strands of montmorillonite clay spheres that form the interconnected strings shown in C; (E) Shouns Prospect sample JC-7D (field photo shown in Fig. 4C) showing porous and anastomosing root-like structures of hollandite-cryptomelane columns with square cross sections, showing increases in size from nucleation sites; and (F) rounded and interwoven lumps of hollandite-cryptomelane columns, also from Shouns Prospect sample JC-7D.
Published: 11 May 2017
Figure 7. Backscattered scanning electron microscope (SEM) photomicrographs from breccia fills and bedding planes of the Shouns Prospect and Erwin Formation showing (A) the surface of Erwin Formation sample SH-1 (hand sample shown in Fig. 5D ) with Mn oxide dendrites surrounded by a rind
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Backscattered scanning electron microscope (SEM) images of (A) romanèchite nodule sample JC-7B from the Shouns Prospect of the Mountain City window (as seen in Fig. 4H); (B) enlarged image of A showing cracked, angular Ba-rich orthoclase (dark gray) encased in romanèchite (white) sheets; (C) breccia matrix of sample SH-2 from the Erwin Formation showing goethite-coated filaments and (D) microlayered romanèchite interbedded with goethite.
Published: 11 May 2017
) sheets; (C) breccia matrix of sample SH-2 from the Erwin Formation showing goethite-coated filaments and (D) microlayered romanèchite interbedded with goethite.
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 Age range of principal latest Mesoproterozoic to earliest Palaeozoic metasedimentary units within the Appalachian and Caledonian orogens, including the Argentine Precordillera. A/D, Ardvreck and Durness groups; BS, Brennevinsfjorden Group; CG, Chilhowie Group; CF, Cerro Totora Formation; Cnt. H.lands, Central Highlands; CV, Catoctin Formation; DS, Dalradian Supergroup; EF, Erwin Formation; ES, Eleonore Bay Supergroup; FdL, Fleur de Lys Succession; GBS, Glen Banchor Succession; KG, Kong Oscar Fjord Group; KS, Krummedal succession; LbG, Lynchburg Group; LG, Labrador Group; MR, Mount Rogers Formation; MS, Moine Supergroup; Mf, Murchisonfjorden Group; MF, Middle Run Formation; OS, Ocoee succession; Nth. H.lands, Northern Highlands; Pal., Palaeozoic; RF, Rome Formation; SG, Stoer Group; SlG, Sleat Group; SS, Sørøy Succession; Sth. Appal., Southern Appalachians; SvS, Svaerholt; TG, Torridon Group; TiG, Tillite Group; W., West. Brown square indicates units with detrital zircon data.
Published: 01 March 2007
; Cnt. H.lands, Central Highlands; CV, Catoctin Formation; DS, Dalradian Supergroup; EF, Erwin Formation; ES, Eleonore Bay Supergroup; FdL, Fleur de Lys Succession; GBS, Glen Banchor Succession; KG, Kong Oscar Fjord Group; KS, Krummedal succession; LbG, Lynchburg Group; LG, Labrador Group; MR, Mount
Journal Article
Journal: GSA Bulletin
Published: 01 January 2014
GSA Bulletin (2014) 126 (1-2): 201–218.
... Formations), and 3) an upper sandstone and shale (Nebo Quartzite, Murray Shale, Hesse Quartzite, and Helenmode, Erwin, and Antietam Formations). Sedimentary analyses show that boundaries of the newly defined facies assemblages transect the named stratigraphic units. Assemblage A consists of fluvial...
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First thumbnail for: Volcanic rift margin model for the rift-to-drift s...
Second thumbnail for: Volcanic rift margin model for the rift-to-drift s...
Third thumbnail for: Volcanic rift margin model for the rift-to-drift s...
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FIGURE 2—Paleogeographic reconstruction of the continents during the Early Triassic with approximate locations of Lower Triassic formations containing trace-fossil assemblages. (A, B) Locations of the Virgin limestone and Sinbad limestone, respectively, southwestern United States. (C) Dinwoody Formation, northwestern United States. (D) Montney Formation, British Columbia, Canada. (E) Toad Formation, southeastern Yukon Territory, Canada. (F) Werfen Formation, Dolomites, southern Italy. Modified from Pruss et al., 2004; after Erwin, 1993
Published: 01 December 2004
Formation, northwestern United States. (D) Montney Formation, British Columbia, Canada. (E) Toad Formation, southeastern Yukon Territory, Canada. (F) Werfen Formation, Dolomites, southern Italy. Modified from Pruss et al., 2004 ; after Erwin, 1993
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Figure 1. Late Permian–Early Triassic paleogeographic map (modified from Erwin, 1993) showing global distribution of Early Triassic wrinkle-structure–bearing strata. Numbers indicate approximate locations where Early Triassic wrinkle structures were formed and preserved: (1) western United States, Spathian Virgin Limestone Member, Moenkopi Formation; (2) western United States, Spathian upper member, Thaynes Formation; (3) northern Italy, Smithian Campil Member, Werfen Formation
Published: 01 May 2004
Figure 1. Late Permian–Early Triassic paleogeographic map (modified from Erwin, 1993 ) showing global distribution of Early Triassic wrinkle-structure–bearing strata. Numbers indicate approximate locations where Early Triassic wrinkle structures were formed and preserved: (1) western United States
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Figure 3
Published: 24 April 2015
in Waggoner ( 1999 ); ( 3 ) Quercus pollardiana -type leaf from the Trapper Creek Formation, Idaho (UCMP #8605); ( 4 ) Quercus pollardiana -type leaf from the Fingerrock Formation, Nevada (UCMP #191949). All scale bars=5 mm. Images courtesy of D. Erwin.
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Generalized distribution of chert from Late Archean time to present. Compiled from Maliva et al. (1989), Siever (1991, 1992), Kidder and Erwin (2001), Perry and Lefticariu (2003), Kidder and Mumma (2003), and Maliva et al. (2005). The estimated frequency distribution of iron formation occurrences in the geologic record is modified from Isley and Abbott (1999).
Published: 01 January 2009
Figure 1. Generalized distribution of chert from Late Archean time to present. Compiled from Maliva et al. (1989) , Siever (1991 , 1992) , Kidder and Erwin (2001) , Perry and Lefticariu (2003) , Kidder and Mumma (2003) , and Maliva et al. (2005) . The estimated frequency distribution
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Generalized model (Hofmann et al., 2013) illustrating the role of habitat saturation in recovery processes. The drop of alpha-diversity in course of an extinction (E) leads to a corresponding loss of beta-diversity and a highly reduced competition among species. A lag phase marks a time interval in which no significant radiation and increase in alpha-diversity is observed (Erwin 2001). After initial diversification (T1, start of recovery interval 1), competition within habitats increases following recovering alpha-diversity. Beta-diversity remains low throughout this interval because adding new species does not result in significant competition for resources. Eventually, alpha-diversity reaches a threshold value where a critical number of species competes for same, limited resources. The time when this habitat saturation is reached is herein referred to as T2. From this time onward (recovery interval 2), species are increasingly restricted to particular niches because of competitive exclusion from neighbouring habitats. Recovery interval 2 ends when all curves level off. Logistic growth of alpha-diversity is adopted from Erwin (2001). The data from the Dinwoody Formation suggest that alpha-diversity is lower than in the Virgin Formation (Hofmann et al., 2013) whereas beta-diversity is low in both units.
Published: 01 September 2013
onward (recovery interval 2), species are increasingly restricted to particular niches because of competitive exclusion from neighbouring habitats. Recovery interval 2 ends when all curves level off. Logistic growth of alpha-diversity is adopted from Erwin (2001 ). The data from the Dinwoody Formation
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Cr Isotope data from shale and iron-rich chemical sediments through time. Shown are Cr isotope data from shales (blue) of this study and Frei et al. (2011, 2013), Gueguen et al. (2016), and Wille et al., (2013), and Cr isotope data from iron formations and ironstones (red) of Frei et al. (2009, 2016), Crowe et al. (2013), and Planavsky et al. (2014). Gray bar indicates bulk silicate Earth (BSE) range. Green bar indicates interval of major eukaryotic diversification based on molecular clock estimates (Erwin et al., 2011) and appearance of early metazoan body fossils (Knoll, 2014).
Published: 01 July 2016
Figure 3. Cr Isotope data from shale and iron-rich chemical sediments through time. Shown are Cr isotope data from shales (blue) of this study and Frei et al. (2011 , 2013 ), Gueguen et al. (2016) , and Wille et al., (2013) , and Cr isotope data from iron formations and ironstones (red
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 Probability plots of latest Neoproterozoic to early Palaeozoic metasedimentary units from along the Appalachian–Caledonian orogen in East Laurentia. Sources of data: Central Appalachians (Unicoi, Erwin, Hardystron formations), Eriksson et al. (2004); Eastern Blue Ridge–Piedmont (including Eastern and Central Blue Ridge, Dahlonega gold belt, Sauratown Mountains window and Smith River Allochthon), Bream et al. (2004) and Carter et al. (2006); Hebridean Foreland (Eriboll Formation, Ardvreck Group), P. A. Cawood et al. (unpubl. data); Newfoundland (Bradore, Hawke Bay, Summerside, South Brook, Blow-Me-Down Brook formations), Cawood & Nemchin (2001); North Central Appalachians (Poughquag Quartzite), McLennan et al. (2001); Precordillera (Cerro Totora Formation), Thomas et al. (2004); Scottish Caledonides (Upper Dalradian Supergroup including Appin, Argyll and Southern Highlands groups), Cawood et al. (2003); Southern Appalachians (Rome Formation), Thomas et al. (2004); Western Blue Ridge, Bream et al. (2004). s, number of samples; n, number of analyses.
Published: 01 March 2007
Fig. 8.  Probability plots of latest Neoproterozoic to early Palaeozoic metasedimentary units from along the Appalachian–Caledonian orogen in East Laurentia. Sources of data: Central Appalachians (Unicoi, Erwin, Hardystron formations), Eriksson et al . (2004) ; Eastern Blue Ridge–Piedmont
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FIGURE 1—Late Permian/Early Triassic paleogeographic map (modified from Erwin, 1993) showing the global distribution of Lower Triassic strata bearing abundant microgastropods. Data are from the literature. Numbers on the map indicate the approximate location where numerous microgastropod-dominated shell beds were deposited during the Early Triassic. The numbered sections are listed below according to where they are exposed today: (1) western United States: Griesbachian Dinwoody Formation (Paull et al., 1989); Nammalian Sinbad Limestone Member, Moenkopi Formation (this study); Smithian Thaynes Formation (Collinson et al., 1976); Smithian Union Wash Formation (Stone et al., 1991); Spathian Virgin Limestone Member, Moenkopi Formation (Jenson, 1984); (2) Greenland: Griesbachian Wordie Creek Formation (Twitchett et al., 2001); (3) Italy: Griesbachian–Smithian Werfen Formation (Broglio Loriga et al., 1986; Broglio Loriga et al., 1990; Wignall and Hallam, 1992; Twitchett and Wignall, 1996); Dienerian Servino Formation (Assereto and Rizzini, 1975); (4) Hungary: Griesbachian Arács Marl and Alcsútdoboz Limestone Formations (Broglio Loriga et al., 1990); (5) Russia: Smithian Zhitkov Formation (T. Oji, pers. comm., 2003); (6) China: Griesbachian Feixianguan Formation (Kershaw et al., 1999); Griesbachian Nanpanjiang Basin (Lehrmann et al., 2003); (7) Japan: Griesbachian Kamura Formation (Sano and Nakashima, 1997); (8) Oman: Griesbachian Wasit block (Krystyn et al., 2003)
Published: 01 June 2004
FIGURE 1 —Late Permian/Early Triassic paleogeographic map (modified from Erwin, 1993 ) showing the global distribution of Lower Triassic strata bearing abundant microgastropods. Data are from the literature. Numbers on the map indicate the approximate location where numerous microgastropod
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Archaeichnium haughtoni Glaessner, 1963, Huns Member, Urusis Formation, UCLA 7309, Arimas farm (1), UCLA 7325, Holoog River (2), and Neiderhagen Member, Nudaus Formation, Kyffhauser farm (3–6). (1) Four longitudinally striated individuals with pointed terminations (arrows), presumed to be the origins of growth, on the base of a 3 cm thick sandstone bed with “old elephant skin” texture, GSN F 1906. (2) Two specimens from the Holoog River, one of which is severely kinked (insert), GSN F 1962 and GSN F 1975, respectively. (3) Superb bed base, GSN F 1939, found by D.E. Erwin in 1995, with at least eight tethered and current-oriented individuals, six facing right and two facing left, with the three best-preserved ones indicated by arrows and shown in (4). (4) Three panels enlarged from (3) to show left-facing (top, GSN F 1939A) and right-facing individuals (middle, GSN F 1939B, bottom GSN F 1939C). (5) External mold, GSN F 1949. (6) An external mold, photographed in the field and then discarded, figured as a pseudofossil by Buatois and Mángano (2016, fig. 2.7c) that clearly shows the pleated nature of the body wall; image kindly provided by Luis Buatois, rotated through –90° so that it appears in positive rather than negative relief. (1) Scale bar = 2 cm; (2, 2 insert, 3, 5, 6) scale bars = 1 cm; (4) scale bar = 5 mm.
Published: 01 October 2024
Figure 21. Archaeichnium haughtoni Glaessner, 1963 , Huns Member, Urusis Formation, UCLA 7309, Arimas farm ( 1 ), UCLA 7325, Holoog River ( 2 ), and Neiderhagen Member, Nudaus Formation, Kyffhauser farm ( 3–6 ). ( 1 ) Four longitudinally striated individuals with pointed terminations (arrows
Journal Article
Journal: GSA Bulletin
Published: 11 May 2017
GSA Bulletin (2017) 129 (9-10): 1158–1180.
... morphologies (sample JC-10). (C) In the Erwin Formation, Mn and Fe oxides are deposited along existing bedding planes in quartzite. (D) Mn oxides in the Erwin Formation are frequently deposited as dendrites up to 1 mm in diameter (sample SH-1). ...
FIGURES
First thumbnail for: New insight into the origin of manganese oxide ore...
Second thumbnail for: New insight into the origin of manganese oxide ore...
Third thumbnail for: New insight into the origin of manganese oxide ore...
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Coarsely and regularly annulated tubes, cf. Calyptrina striata Sokolov, 1967 (2–6), smooth tubes (1, 7), and two important specimens of Archaeichnium haughtoni Glaessner, 1963 (8, 9) from the Neiderhagen Member, Nudaus Formation, UCLA 7320, Kyffhauser farm (1–4), the Huns Member, Urusis Formation, UCLA 7325, Holoog River (5, 7), and UCLA 7309, Arimas farm (5, 8, 9). (1) Bed base with sandstone casts of numerous small, short, conical tubes plus one wider, coarsely annulated, kinked tube (arrow), GSN F 1941. (2) Base of gutter with sandstone cast of one coarsely annulated tube, GSN F 1944. (3) Top of tube-filled gutter cast, found by D.H. Erwin in 1995, with one annulated tube indicated by the arrow, GSN F 1943. (4) Top, end, and base of small section of a gutter cast with one enclosed coarsely annulated tube indicated by the arrow, GSN F 1945. (5) Cast of irregular annulated tube on bed base, Holoog River, GSN F 1973. (6) A somewhat similar structure, Arimas, GSN F 1934. (7) Small sandstone slab with casts, many presumably current-aligned smooth tubes, GSN F 1976. (8) Recognizable specimen of Archaeichnium haughtoni that is on the same surface as the “Arimas lycopod” (Fig. 14.5), thus demonstrating co-occurrence of these two taxa, GSN F 1910. (9) Quartz filling of Archaeichnium haughtoni that gives some information about its cross-sectional shape before burial and compaction, GSN F 1919. (1, 3, 4, 7) Scale bars = 2 cm; (2, 5, 6, 8, 9) scale bars = 1 cm.
Published: 01 October 2024
Figure 22. Coarsely and regularly annulated tubes, cf. Calyptrina striata Sokolov, 1967 ( 2–6 ), smooth tubes ( 1, 7 ), and two important specimens of Archaeichnium haughtoni Glaessner, 1963 ( 8, 9 ) from the Neiderhagen Member, Nudaus Formation, UCLA 7320, Kyffhauser farm ( 1–4
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FIGURE 6—Comparison of abundance of microgastropod species in Permian, Early Triassic, and Middle Triassic examples. Only adult gastropod measurements were included in all counts. (A) The Permian gastropod fauna of the southwestern United States that was examined was described by Chronic (1952), Yochelson (1956), Batten (1958), Winters (1963), Erwin (1988 a, b, c), and Batten (1989). This fauna includes fossils of Wolfcampian, Leonardian, and Guadalupian ages. Larger gastropod and microgastropod species from 18 superfamilies (Pleurotomariacea, Euomphalacea, Trochonematacea, Trochacea, Subulitacea, Cerithiacea, Loxonematacea, Pseudophoracea, Anomphalacea, Craspedostomatacea, Platyceratacea, Portlockiellidae, Phymatopleuridae, Eotomariidae, Acteonacea, Pyramidellacea, Patellacea, and Microdomatoidea) were counted and the percentage of microgastropod species was calculated. (B) Data for the Sinbad Limestone Member gastropod species were obtained from Batten and Stokes (1986). In the Sinbad Limestone Member, Coelostylina angulifera, Zygopleura haasi, and Battenizyga eotriassica are not microgastropod species. Larger gastropod and microgastropod species from 6 superfamilies were tallied and the percentage of microgastropod species was calculated. (C) The gastropod fauna of the early Middle Triassic (Anisian) Qingyan Formation in south China used was described by Yin and Yochelson (1983 a, b, c). Larger gastropod and microgastropod species from 6 superfamilies (Pleurotomariacea, Murchisoniacea, Trochacea, Neritacea, Euomphalacea, and Loxonematacea) were tallied and the percentage of microgastropod species was calculated
Published: 01 June 2004
) , Yochelson (1956) , Batten (1958) , Winters (1963) , Erwin (1988 a , b , c ), and Batten (1989) . This fauna includes fossils of Wolfcampian, Leonardian, and Guadalupian ages. Larger gastropod and microgastropod species from 18 superfamilies (Pleurotomariacea, Euomphalacea, Trochonematacea, Trochacea