DOCSLIB.ORG

Early Paleozoic Rifting and Reactivation of a Passive-Margin Rift: Insights from Detrital Zircon Provenance Signatures of the Potsdam Group, Ottawa Graben: Comment

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Early Paleozoic Rifting and Reactivation of a Passive-Margin Rift: Insights from Detrital Zircon Provenance Signatures of the Potsdam Group, Ottawa Graben: Comment Comment and Reply Early Paleozoic rifting and reactivation of a passive-margin rift: Insights from detrital zircon provenance signatures of the Potsdam Group, Ottawa graben: Comment Ed Landing1,†, Osman Salad Hersi2, Lisa Amati1, Stephen R. Westrop3, and David A. Franzi4 1New York State Museum, 222 Madison Avenue, Albany, New York 12230, USA 2Department of Geology, University of Regina, Regina, Saskatchewan S4S 0A2, Canada 3Oklahoma Museum of Natural History and School of Geology and Geophysics, University of Oklahoma, Norman, Oklahoma 73091, USA 4Center for Earth and Environmental Sciences, State University of New York at Plattsburgh, Plattsburgh, New York 12901, USA This comment outlines fundamental prob- relief, much Quaternary cover, and many syn- ford and Arnott’s (2010) Covey Hill (Ausa ble) lems in Lowe et al.’s synthesis (2018) of the and post-depositional faults. As suggested, in Formation and is a different stratigraphic con- early Paleozoic stratigraphic architecture of part, above, problems in Lowe et al.’s (2018, also cept as they assigned the Chippewa Bay and the eastern Ottawa-Bonnechere aulacogen that 2017) OBa synthesis include: (1) a stratigraphic Edwardsville members of Sanford and Arnott preclude an accurate analysis of the region’s nomenclature that redefines, without comment, (2010) to their Keeseville Formation. Another geological and depositional history and even an a number of earlier defined units (e.g., their nomenclatural problem in Lowe et al. (2018, adequate stratigraphic provenance of the detrital “Potsdam” and “Hannawa Falls”); (2) exten- also 2017) is restriction and upgrading of San- zircons that they analyze. These problems in- sion of the “Potsdam Group” up into the Ordo- ford and Arnott’s (2010) Hannawa Falls Mem- clude: inaccurate lithostratigraphic and contra- vician; (3) correlations (e.g., their “Rivière aux ber (to 199 m of red fluvial siliciclastics and up- dictory biostratigraphic correlations that have Outardes Member”) that subvert the allostrati- per dune sand) within the Covey Hill (Ausable) also led to extension of the Potsdam “Group” graphic synthesis; (4) not relating the succession Formation to 0–25 m of aeolian sandstone of into the Lower Ordovician; a proposed allo stra- to eustatic signatures and sequence stratigraphy a “Hannawa Falls Formation” that overlies the tigraphy that contradicts itself when tested with elsewhere in east Laurentia; (5) biostratigraphic Ausable. NACSN (2005) recommendations on existing litho- and biostratigraphic data; redefi- errors in correlation; (6) misrepresentation of “redefinition” mean the Hannawa Falls of San- nitions of earlier defined lithostratigraphic units stratigraphic contacts and depositional facies ford and Arnott (2010) should have a different that lead to confusion on close reading; and er- (e.g., Altona and Theresa formations). name when “restricted” to the dune sandstone. rors in interpreted depositional environments The older rocks in the eastern OBa are termed Furthermore, the selection of different horizons and lithostratigraphic contacts. “Potsdam Formation” in the type area of north- for the Covey Hill (Ausable)–Keeseville contact Rodinia break-up and the early Paleozoic his- ern New York, and have a feldspar-rich, nonfos- leads to distinction of a “Potsdam Group” sensu tory of NE Laurentia are recorded by structural siliferous lower interval and an upper, generally Sanford and Arnott (2010), sensu Lowe et al. evidence, volcanics, and siliciclastic rocks asso- white-colored quartz arenite unit (respectively, (2017, 2018), and sensu Clark (1966). Such ciated with an ~700-km-long graben system that Ausable and Keesville members; e.g., Fisher, awkward terms are simplified below by use of extends from the Sudbury, Ontario, region into 1968; Landing et al., 2009; Fig. 1). Clark (1966) the traditional “Potsdam Formation” (Fig. 1). the Appalachian orogen. This down-dropped elevated the Potsdam to group status, likely as he The generally unfossiliferous, lowest silici- Ottawa-Bonnechere aulacogen (OBa), a major wanted to subdivide the sandstones members, clastics in the eastern OBa (SE Ontario–north- cratonic graben terminating in an orogen, is one but did not then have the ability to name formal ern New York–SW Quebec) are regarded in of the oldest recognized aulocogens (Shatsky, submembers, as proposed by the North Ameri- many reports to record Ediacaran subsidence 1946, 1955; Burke, 1977; Landing et al., 2009). can Commission on Stratigraphic Nomenclature (e.g., Sanford and Arnott, 2010, their fig. 5; It may be the failed arm of a triple junction, sug- (NACSN, below; Brett et al., 2018). “Potsdam review in Landing et al., 2009). However, the gested by evidence of a mantle plume in north- Group” is not a uniform concept. Clark’s (1966) oldest sedimentary rocks of the eastern OBa ern Vermont (Fig. 1, Tibbet Hill volcanics), or a “Potsdam Group” included upper sandstones are surprisingly young and show abrupt late rift segment offset by transform faults (review and dolostones now brought to the Lower Ordo- Early Cambrian marine onlap with subsidence in Webster and Landing, 2016). The age(s) and vician Theresa Formation, and Sanford and of the “mouth” of the OBa south and SSW of vertical and lateral continuity of sedimentary Arnott (2010) and Lowe et al. (2017, 2018) Montreal, with coeval faulting and down-drop rocks are key to determining sediment and de- expanded the “Group” by including the litho- of the northern Vermont shelf ~80 km ESE to trital zircon provenance and paleogeography of logically dissimilar Altona Formation (Landing form the anoxic Franklin Basin (Landing, 2007, the OBa. Lowe et al. (2018, also 2017) combine et al., 2009) as a basal member, while defining 2012; Landing et al., 2007, 2009; Fig. 1). This outcrop with drill core data in an area with low nomenclaturally different “Potsdam” subdivi- rejuvenation of a passive margin (eastern OBa sions. Thus, the Ausable Formation sensu Lowe and on-strike Franklin Basin) persisted into †ed.landing@ nysed .gov et al. (2018) is up to 400 m thicker than San- the middle Cambrian with deposition of higher GSA Bulletin; March/April 2019; v. 131; no. 3/4; p. 695–698; https://doi.org/10.1130/B35104.1; 1 figure; published online 25 January 2019. For permission to copy, contact [email protected] Geological Society of America Bulletin, v. 131, no. 3/4 695 © 2019 Geological Society of America Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/131/3-4/695/4656042/695.pdf by guest on 25 September 2021 Comment and Reply Figure 1. Composite eastern OBa and Frank- of the Altona in its type area (Landing et al., lin Basin successions (modified from Land- 2009, their fig. 4). Almost all “Altona” localities ing et al., 2009, fig. 9). Covey Hill Ausable)( that yielded Proterozoic detrital zircons (Lowe of Sanford and Arnott (2010) to 400 m et al., 2018, their table 1, samples AS-2–5) are thicker than Ausable of Lowe et al. (2018); “braided fluvial.” This is not an Altona facies intra-Keeseville unconformity (Lowe et al., (Landing et al., 2009) and is better referred to 2018) not reported in equivalent Cairnside- as an “undifferentiated Ausable Formation.” Keeseville-Nepean Formation (Sanford and Reevaluation of Lowe et al.’s (2018) “Altona” Arnott, 2010). RaO is purported Rivière outcrops in Quebec and Ontario may be needed. aux Outardes Member of Keeseville For- The Altona Formation is an important unit mation of Lowe et al. (2017, 2018), but is in the OBa. It is relatively thick in its type area a siliciclastic-dolostone interval correlated (84 m) and the only Cambrian OBa unit that is herein with Tribes Hill Formation and iden- bracketed biostratigraphically. Upper lower and tical Saint-Clotilde Member. Figure divides middle Middle Cambrian trilobites from the Al- Cambrian into three global subseries (e.g., tona (Landing et al., 2009) indicate it brackets Landing et al., 2018, fig. 1 caption and ref- an ~7 m.y. interval (i.e., late Early and middle erences therein): Lower—Terreneuvian Middle Cambrian dates in Landing et al., 1998, Series + Series 2; Middle—Mialoingian 2015) that may exceed any other OBa Cambrian Series; Upper—Paibaian Series. Abbrevia- unit in duration. tions: C.—Cambrian; carb.—carbonate; The Altona is not a “tidal flat” facies (i.e., Lowe Dap.—Dapingian; E.—Ehmaniella; Fm.— et al., 2018, fig. 3; also 2017). Trough cross-bed- Formation; Gp.—Group; Kees.—Kees- ded sandstone likely deposited under trade wind eville; l./low./Low.—lower/lower/Lower; control dominates in lower member 1, and hum- ls.—limestone; m—middle; Mbr.—Mem- mocky cross-stratified (HCS) sandstone occurs ber; O.—Olenellus; P.-P.—Prosaukia- in upper member 2 (Landing et al., 2009; Lowe Ptychaspis; phyll.—phyllite; RaO—“Rivière et al., 2017, their fig. 8A). As HCS has depths of aux Outardes”; ss.—sandstone; u.—upper; formation of 13–50 m (e.g., Dumas and Arnott, U.—Ulrichodina quadraplicatus, V.—Vari- 2006), assignment of the Altona to a tidal flat abiloconus bassleri. facies is incorrect. Thick dolostones with large burrows in the upper Altona do not reflect inter- tidal, evaporitic facies (Lowe et al., 2017, p. 7) but record the hydrothermal dolomitization marine deposits of the Altona Formation and with minor sulphide mineralization common in their upward replacement by Ausable Formation eastern New York (Landing et al., 2007, 2009). fluviatile arkoses (Landing et al., 2009). Thinner dolostones with planar laminae (e.g., Sanford and Arnott (2010, p. 26) substituted Lowe et al., 2017, their figs. 8B and 8C) likely “Jericho Member” for Landing et al.’s (2009) show downslope(?) transport of carbonate and Altona Formation and noted the latter “were quartz silt, and the dolomite–organic-rich lami- presumably unaware of the term “Jericho Mem- nae figured by Lowe et al. (2017, figs. 8B, 8C) ber” previously proposed for the same strata” in are not intertidal “microbial mats” but horizontal a 2004 technical report for the New York State stylolites.
Load more

Recommended publications
  • Geochemistry This
    TORONTOTORONTO Vol. 8, No. 4 April 1998 Call for Papers GSA TODAY — page C1 A Publication of the Geological Society of America Electronic Abstracts Submission — page C3 Antarctic Neogene Landscapes—In the 1998 Registration Refrigerator or in the Deep Freeze? Annual Issue Meeting — June GSA Today Introduction The present Molly F. Miller, Department of Geology, Box 117-B, Vanderbilt Antarctic landscape undergoes very University, Nashville, TN 37235, [email protected] slow environmental change because it is almost entirely covered by a thick, slow-moving ice sheet and thus effectively locked in a Mark C. G. Mabin, Department of Tropical Environmental Studies deep freeze. The ice sheet–landscape system is essentially stable, and Geography, James Cook University, Townsville, Queensland 4811, Australia, [email protected] Antarctic—Introduction continued on p. 2 Atmospheric Transport of Diatoms in the Antarctic Sirius Group: Pliocene Deep Freeze Arjen P. Stroeven, Department of Quaternary Research, Stockholm University, S-106 91 Stockholm, Sweden Lloyd H. Burckle, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964 Johan Kleman, Department of Physical Geography, Stockholm University, S-106, 91 Stockholm, Sweden Michael L. Prentice, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824 INTRODUCTION How did young diatoms (including some with ranges from the Pliocene to the Pleistocene) get into the Sirius Group on the slopes of the Transantarctic Mountains? Dynamicists argue for emplacement by a wet-based ice sheet that advanced across East Antarctica and the Transantarctic Mountains after flooding of interior basins by relatively warm marine waters [2 to 5 °C according to Webb and Harwood (1991)].
    [Show full text]
  • GSA TODAY December Vol
    Vol. 10, No. 12 December 2000 INSIDE • Northeastern Section Meeting, p. 11 GSA TODAY • Southeastern Section Meeting, p. 15 A Publication of the Geological Society of America • GeoCorps America™, p. 36 Beneath Yellowstone: Evaluating Plume and Nonplume Models Using Teleseismic Images of the Upper Mantle Eugene D. Humphreys, Department of Geological Sciences, University of Oregon, Eugene, OR 97403-1272, USA Kenneth G. Dueker, Department of Geology, University of Wyoming, Laramie, WY 82071-3006, USA Derek L. Schutt, Department of Geological Sciences, University of Oregon, Eugene, OR 97403-1272, USA Robert B. Smith, Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112-1183, USA ABSTRACT swell provide insight on the origin of ing teleseismic data in the greater Yellow- hotspots. The upper mantle beneath this stone area should answer most questions The Yellowstone hotspot commonly swell now is one of the most seismically currently deemed important about this is thought to result from a stationary resolved regions on Earth, and the physi- hotspot. mantle plume rooted in the lower man- cal state of the upper mantle is accord- Hotspots are defined by their anoma- tle over which North America moves. Yet ingly well understood. However, interpre- lous surface manifestations, in particular, Yellowstone’s initiation and its associa- tation of our findings in terms of hotspot the time-transgressive propagation of vol- tion with the “backward” propagating processes remains ambiguous. Where once canism over hundreds of kilometers, often Newberry hotspot across eastern Oregon a plume origin seemed natural, we now pose difficult questions to those explain- consider a nonplume explanation to be at ing Yellowstone as a simple consequence least as attractive.
    [Show full text]
  • (Re)Proposal of Three Cambrian Subsystems and Their Geochronology
    Article 273 by Ed Landing1*, Gerd Geyer2, Mark D. Schmitz3, Thomas Wotte4, and Artem Kouchinsky5 (Re)proposal of three Cambrian Subsystems and their Geochronology 1 New York State Museum, 222 Madison Avenue, Albany, NY, USA; *Corresponding author, E-mail: [email protected] 2 Lehrstuhl für Geodynamik und Geomaterialforschung, Institut für Geographie und Geologie, Bayerische Julius-Maximilians Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany 3 Department of Geosciences, Boise State University, 1910 University Drive, Boise, Idaho 83725, USA 4 Department of Palaeontology, TU Bergakademie Freiberg, Bernhard-von-Cotta-Straße, D-09599 Freiberg, Germany 5 Department of Palaeontology, Swedish Museum of Natural History, Box 50007, SE-104 05, Stockholm, Sweden (Received: April 29, 2020; Revised accepted: September 24, 2020) https://doi.org/10.18814/epiiugs/2020/020088 The Cambrian is anomalous among geological systems 2018). Following work by the International Subcommission on Cam- as many reports divide it into three divisions of indetermi- brian Stratigraphy (ISCS), these key biotic developments can be related nate rank. This use of “lower”, “middle”, and “upper” has to the chronostratigraphic subdivision of the Cambrian System into been a convenient way to subdivide the Cambrian despite four global series and ten stages (e.g., Babcock, 2005; Babcock and agreement it consists of four global series. Traditional divi- Peng, 2007) complemented by an increasingly precise U-Pb (numeri- sions of the system into regional series (Lower, Middle, cal) geochronology (Fig. 1). This decision at the 2004 ISCS meeting Upper) reflected local biotic developments not interpro- meant that the traditional subdivisions of the Cambrian into regional “Lower,” “Middle,” and “Upper” series (discussed below) were no lon- vincially correlatable with any precision.
    [Show full text]
  • Summer 2008 Issue
    PRISCUM The Newsletter of the Paleontological Society Editor: Lisa Amati, Department of Geology, State University of New York, Potsdam ([email protected]) Summer 2008 Table of Contents Schedule of PS Sponsored Events at 2008 GSA 2 President’s Report 5 Spotlight on Research 6 2007 Paleontological Society Student Awards 7 2007 Paleontological Society Student Poster Award 8 Winners New Student Joins the PS Council 8 Actions of the 2008 Midyear Council Meeting 9 Education and Outreach Report 10 News from the Sections 11 International Rudist Conference 11 Book Reviews 12 Mystery Fossil - Ezekiel’s Wheel 17 Notices 20 PRISCUM 1 Sequoia Club mid-career leaders to address the spectrum of research questions that are motivating their research. New ap- Paleontological Society proaches to issues ranging across all of paleontology, each with new results, are on the program. Geobiology, evolu- Sponsored Events tion, vertebrate paleontology, systematics, isotope studies, paleobiogeography, paleoecology, paleobotany and more Centennial Celebration are represented. This will be a day to connect with the "new" multidisciplinary paleontology. Join us and expand GSA 2008 your horizons. Speakers include: Abigail Allwood, Kevin October 4-9th, Houston, Texas Boyce, Christopher Brochu, Andrew Bush, Gregory Dietl, Gene Hunt, Hope Jahren, Rowan Lockwood, Gordon Love, Ryosuke Motani, Shanan Peters, Kevin Peterson, David Sepkoski, Alycia Stigall, Colin Sumrall, Leif Tapa- This schedule lists only events sponsored by the Paleon- nila, Peter Wilf, and Shuhai Xiao. tological Society. A full meeting schedule is available on the meeting website: https://www.acsmeetings.org/. Please note that all sessions will be held in the Brown Convention Center unless otherwise noted.
    [Show full text]
  • Legacy of the Locust—Dudley and Its Famous Trilobite Calymene Blumenbachii
    LEGACY OF THE LOCUST—DUDLEY AND ITS FAMOUS TRILOBITE CALYMENE BLUMENBACHII DONALD G. MIKULIC AND JOANNE KLUESSENDORF Illinois State Geological Survey, Champaign, IL 61820, [email protected], and Weis Earth Science Museum, University of Wisconsin-Fox Valley, Menasha, Wisconsin 54952, [email protected] ABSTRACT—The trilobite Calymene blumenbachii from the Silurian at Dudley, England, had a fundamental role in the early study of this prominent group of extinct arthropods. Discovered during the mid-1700s, this was the first trilo- bite known from numerous complete and well-preserved fossils anywhere in the world. Commonly known as the Dudley Fossil or Dudley Locust, exceptional specimens of this trilobite became widely distributed in collections throughout Europe. As a result, they were central to the most influential trilobite papers of the time including those of Walch (1771) and Brongniart (1822). Many basic characteristics of the group, including their ability to enroll, were first established through the study of these fossils. In turn, this information provided the key evidence used to estab- lish the arthropod affinities of this group. During the late eighteenth century, all trilobites were commonly referred to as Dudley Fossils, and demonstrate the initial importance and prominence of this species. It became the standard of comparison in trilobite research, as well as the textbook example for these fossils. No other trilobite contributed as much to the early understanding of these ancient animals. The scientific prominence of Calymene blumenbachii derived from geologic and economic factors. The limestones at Dudley contained an exceptionally rich biota of well-preserved Silurian fossils, of which this trilobite was the most notable.
    [Show full text]
  • United States Department of the Interior Geological
    UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY CONODONT BIOSTRATIGRAPHY AND THERMAL COLOR ALTERATION INDICES OF THE UPPER ST. CHARLES AND LOWER GARDEN CITY FORMATIONS, BEAR RIVER RANGE, NORTHERN UTAH AND SOUTHEASTERN IDAHO by Ed Landing Open-File Report 81-740 1981 CONODONT BIOSTRATIGRAPHY AND THERMAL COLOR ALTERATION INDICES OF THE UPPER ST. CHARLES AND LOWER GARDEN CITY FORMATIONS, NORTHERN UTAH AND SOUTHEASTERN IDAHO by Ed Landing1 ABSTRACT The contact between the St. Charles and Garden City Formations in the Bear River Range, Bannock thrust sheet in northern Utah and southeastern Idaho, is a diachronous disconformity within the Lower Ordovician. Middle or, possibly, upper Cordylodus proavus Zone (Clavohamulus elongatus to, possibly, C. hintzei Subzones) conodonts indicate that lowermost Canadian Series (Lower Ordovician in North American usage) strata equivalent to the Missisquoia Zone and, possibly, lower Symphysurina Zone (trilobites) are present in the upper part of the St. Charles Formation. The boundary between the Trempealeauan Stage and Canadian Series (Cambrian-Ordovician boundary) is located within the upper part of the St. Charles Formation. Basal beds of the Garden City Formation contain conodonts representing Fauna B (upper part) in two Idaho sections and Fauna C at two Utah localities. At least 12 m (40 feet) of erosional relief was Present address: New York State Geological Survey, State Education Department, Albany, New York 12230 developed on the dolostones of the St. Charles Formation prior to deposition of the Garden City Formation. Trilobite Zone A of Ross from the lower part of the Garden City Formation correlates with the upper part of the Symphysurina Zone (S_.
    [Show full text]
  • GSA TODAY • Stealth Attack on Science, P
    Vol. 7, No. 3 March 1997 INSIDE GSA TODAY • Stealth Attack on Science, p. 37 • Award Citations, Responses, p. 13 A Publication of the Geological Society of America • Employment Service, p. 41 Debating the Environmental Factors in Hominid Evolution Craig S. Feibel, Department of Anthropology, Douglass Campus, Rutgers University, New Brunswick, NJ 08903-0270 ABSTRACT Environmental factors, particularly climatic fluctu- ations, are widely viewed as important controls on the path of evolution. The broad coincidence of two adaptive transitions in hominid evolution with major climatic milestones supports models in which these evolutionary shifts are climatically driven. In the first, the origin of the Hominidae is tied to the Messinian desiccation of the Mediterranean. A second, more convincing case, involves the origin of the genus Homo and the first appearance of stone-tool technology, which occur in broad contem- poreneity with the onset of Northern Hemisphere glacia- tion in the Pliocene. Detailed analysis, however, encoun- ters difficulties in tying large-scale forcing phenomena to the terrestrial evidence for hominid evolution, and in resolving the effects of interacting environmental factors. The influences of climate, tectonics, volcanism, and community evolution all act at varying scales, and are reflected in different ways in the geologic record. Current research is tying detailed studies from the African conti- nent to records of global change, and to better under- Figure 1. The hominid cranium standing of the interactive effects of various environ- KNM-ER 1470, attributed to Homo mental factors with human evolution. rudolfensis (Wood, 1992), illustrates the enlarged braincase that chatacter- izes the genus Homo. Photo courtesy INTRODUCTION of the National Museums of Kenya.
    [Show full text]
  • Landing Et Al., 2007.Pdf
    287 by Ed Landing1, Shanchi Peng2, Loren E. Babcock3, Gerd Geyer4, and Malgorzata Moczydlowska-Vidal5 Global standard names for the Lowermost Cambrian Series and Stage 1 New York State Museum, Madison Avenue, Albany, New York 12230, USA. Email: [email protected] 2 State Key Laboratory of Stratigraphy and Palaeobiology, Nanjing Institute of Geology and Palaeontology, 39 East Beijing Road, Nanjing 210008, China. Email: [email protected] 3 School of Earth Sciences, The Ohio State University, Columbus, Ohio 43210, USA. Email: [email protected] 4 Institut für Paläontologie, Bayerische Julius-Maximillians-Universität, Pleicherwall 1, D97070 Würzburg, Germany. Email: [email protected] 5 Department of Earth Sciences, Uppsala University, Norbyvägen 22, Sweden. Email: [email protected] The GSSP marking the base of the Cambrian System was ratified by the IUGS in 1992. Ratification of the GSSP Terreneuvian Series point at the base of the Trichophycus pedum Ichnozone Name of the series in the Fortune Head section, eastern Newfoundland, Canada, automatically defined the conterminant base of The name “Terreneuvian Series” replaces the provisional name “Cambrian Series 1.” The base has been defined at a point 2.3 m the lowermost series and stage of the Cambrian although above the base of what was referred to as “member 2” of the Chapel names for those subdivisions were not proposed at the Island Formation (Figures 1, 2) in the measured section of Narbonne time of the decision. In 2007, the IUGS ratified the names et al. (1987) of the Fortune Head section, Burin Peninsula, New- foundland, Canada. The units earlier termed members 1 and 2 of the Terreneuvian Series and Fortunian Stage for these previ- Chapel Island Formation now comprise the lower part of the Mys- ously unnamed chronostratigraphic subdivisions.
    [Show full text]
  • Terreneuvian Stratigraphy and Faunas from the Anabar Uplift, Siberia
    Terreneuvian stratigraphy and faunas from the Anabar Uplift, Siberia ARTEM KOUCHINSKY, STEFAN BENGTSON, ED LANDING, MICHAEL STEINER, MICHAEL VENDRASCO, and KAREN ZIEGLER Kouchinsky, A., Bengtson, S., Landing, E., Steiner, M., Vendrasco, M., and Ziegler, K. 2017. Terreneuvian stratigraphy and faunas from the Anabar Uplift, Siberia. Acta Palaeontologica Polonica 62 (2): 311‒440. Assemblages of mineralized skeletal fossils are described from limestone rocks of the lower Cambrian Nemakit-Daldyn, Medvezhya, Kugda-Yuryakh, Manykay, and lower Emyaksin formations exposed on the western and eastern flanks of the Anabar Uplift of the northern Siberian Platform. The skeletal fossil assemblages consist mainly of anabaritids, molluscs, and hyoliths, and also contain other taxa such as Blastulospongia, Chancelloria, Fomitchella, Hyolithellus, Platysolenites, Protohertzina, and Tianzhushanella. The first tianzhushanellids from Siberia, including Tianzhushanella tolli sp. nov., are described. The morphological variation of Protohertzina anabarica and Anabarites trisulcatus from their type locality is documented. Prominent longitudinal keels in the anabaritid Selindeochrea tripartita are demon- strated. Among the earliest molluscs from the Nemakit-Daldyn Formation, Purella and Yunnanopleura are interpreted as shelly parts of the same species. Fibrous microstructure of the outer layer and a wrinkled inner layer of mineralised cuticle in the organophosphatic sclerites of Fomitchella are reported. A siliceous composition of the globular fossil Blastulospongia
    [Show full text]
  • First Evidence for Cambrian Glaciation Provided By
    Palaeogeography, Palaeoclimatology, Palaeoecology 285 (2010) 174–185 Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo First evidence for Cambrian glaciation provided by sections in Avalonian New Brunswick and Ireland: Additional data for Avalon–Gondwana separation by the earliest Palaeozoic Ed Landing a,⁎, Breandán Anraoi MacGabhann b a New York State Museum, 222 Madison Avenue, Albany, New York 12230, United States b Department of Earth and Ocean Sciences, School of Natural Sciences, National University of Ireland, University Road, Galway, Ireland article info abstract Article history: The first evidence for Cambrian glaciation is provided by two successions on the Avalon microcontinent. The Received 8 May 2009 middle lowest Cambrian (middle Terreneuvian Series and Fortunian Stage–Stage 2 boundary interval) has an Received in revised form 31 October 2009 incised sequence boundary overlain by a fluvial lowstand facies and higher, olive green, marine mudstone on Accepted 5 November 2009 Hanford Brook, southern New Brunswick. This succession in the lower Mystery Lake Member of the Chapel Available online 11 November 2009 Island Formation may be related to melting of an ice sheet in Avalon. The evidence for this interpretation is a muddy diamictite with outsized (up to 10 cm in diameter), Proterozoic marble and basalt clasts that Keywords: Cambrian penetrated overlying laminae in the marine mudstone. That eustatic rise was associated with the mudstone Glaciation deposition is suggested by an approximately coeval rise that deposited sediments with Watsonella crosbyi Diamictite Zone fossils 650 km away in Avalonian eastern Newfoundland. A sea-level rise within the Watsonella crosbyi Sequence stratigraphy Chron, at ca.
    [Show full text]
  • Ediacaran–Ordovician of East Laurentia— S
    EDIACARAN–ORDOVICIAN OF EAST LAURENTIA— S. W. FORD MEMORIAL VOLUME THE UNIVERSITY OF THE STATE OF NEW YORK Regents of The University ROBERT M. BENNETT, Chancellor, B.A., M.S. .......................................................................................................... Tonawanda MERRYL H. TISCH, Vice Chancellor, B.A., M.A. Ed.D. ........................................................................................... New York SAUL B. COHEN, B.A., M.A., Ph.D. ........................................................................................................................ New Rochelle JAMES C. DAWSON, A.A., B.A., M.S., Ph.D. ........................................................................................................... Peru ANTHONY S. BOTTAR, B.A., J.D. .............................................................................................................................. Syracuse GERALDINE D. CHAPEY, B.A., M.A., Ed.D. ............................................................................................................ Belle Harbor ARNOLD B. GARDNER, B.A., LL.B. .......................................................................................................................... Buffalo HARRY PHILLIPS, 3rd, B.A., M.S.F.S. ....................................................................................................................... Hartsdale JOSEPH E. BOWMAN,JR., B.A., M.L.S., M.A., M.Ed., Ed.D. ................................................................................. Albany
    [Show full text]
  • Darwin's Lost World
    DARWIN’SLOSTWORLD This page intentionally left blank DARWIN’S LOST WORLD .......................t ....................... The Hidden History of Animal Life Martin Brasier 1 3 Great Clarendon Street, Oxford ox26dp Oxford University Press is a department of the University of Oxford. It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide in Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi New Delhi Shanghai Taipei Toronto With offices in Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore South Korea Switzerland Thailand Turkey Ukraine Vietnam Oxford is a registered trade mark of Oxford University Press in the UK and in certain other countries Published in the United States by Oxford University Press Inc., New York # Martin Brasier 2009 The moral rights of the author have been asserted Database right Oxford University Press (maker) First published 2009 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, or under terms agreed with the appropriate reprographics rights organization. Enquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above You must not circulate this book in any other binding or cover and you must impose the same condition on any acquirer British Library Cataloguing in Publication Data Data available Library of Congress Cataloging in Publication Data Data available Typeset by SPI Publisher Services, Pondicherry, India Printed in Great Britain on acid-free paper by Clays Ltd., Bungay, SuVolk ISBN 978–0–19–954897–2 13579108642 ................................................
    [Show full text]