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The Earliest Bioturbators As Ecosystem Engineers
Downloaded from http://sp.lyellcollection.org/ by guest on September 27, 2021 Engineering the Cambrian explosion: the earliest bioturbators as ecosystem engineers LIAM G. HERRINGSHAW1,2*, RICHARD H. T. CALLOW1,3 & DUNCAN MCILROY1 1Department of Earth Sciences, Memorial University of Newfoundland, Prince Philip Drive, St John’s, NL, A1B 3X5, Canada 2Geology, School of Environmental Sciences, University of Hull, Cottingham Road, Hull HU6 7RX, UK 3Statoil ASA, Stavanger 4035, Norway *Correspondence: [email protected] Abstract: By applying modern biological criteria to trace fossil types and assessing burrow mor- phology, complexity, depth, potential burrow function and the likelihood of bioirrigation, we assign ecosystem engineering impact (EEI) values to the key ichnotaxa in the lowermost Cambrian (Fortunian). Surface traces such as Monomorphichnus have minimal impact on sediment properties and have very low EEI values; quasi-infaunal traces of organisms that were surficial modifiers or biodiffusors, such as Planolites, have moderate EEI values; and deeper infaunal, gallery biodiffu- sive or upward-conveying/downward-conveying traces, such as Teichichnus and Gyrolithes, have the highest EEI values. The key Cambrian ichnotaxon Treptichnus pedum has a moderate to high EEI value, depending on its functional interpretation. Most of the major functional groups of mod- ern bioturbators are found to have evolved during the earliest Cambrian, including burrow types that are highly likely to have been bioirrigated. In fine-grained (or microbially bound) sedimentary environments, trace-makers of bioirrigated burrows would have had a particularly significant impact, generating advective fluid flow within the sediment for the first time, in marked contrast with the otherwise diffusive porewater systems of the Proterozoic. -
Palaeobiological and Palaeonvironmental Significance of the Pliocene Trace Fossil Dactyloidites Peniculus
Palaeobiological and palaeonvironmental significance of the Pliocene trace fossil Dactyloidites peniculus ALFRED UCHMAN and PETER PERVESLER Uchman, A. and Pervesler, P. 2007. Palaeobiological and palaeonvironmental significance of the Pliocene trace fossil Dactyloidites peniculus. Acta Palaeontologica Polonica 52 (4): 799–808. The radial trace fossil Dactyloidites peniculus occurs in a deep tier in totally bioturbated shoreface sediments of Pliocene age in the Stirone Valley, N Italy, together with Thalassinoides isp. and Ophiomorpha nodosa. Long, narrow shafts run− ning from centre of the radiating structure and abundant faecal pellets in the radial structure were discovered. The trace maker of D. peniculus, probably a polychaete, deposited the pellets deeply in the sediment, probably for reinforcement of the tubes and a gardening of microbes for feeding. This trace fossil exclusively occurs within a narrow horizon at the top of a shallowing−up section interpreted as a high−stand system tract, below a discontinuity surface capped by finer sedi− ments. D. peniculus was formed in soft sandy sediments under stable conditions related to the latest phases of the high− stand system tract. Therefore, it is a candidate for indication of similar environmental situations having a soft sandy, but stable sea floor. Key words: Tracefossils,Dactyloidites, gardening, sequence stratigraphy, marine flooding, foredeep, Neogene, Pliocene. Alfred Uchman [[email protected]] Institute of Geological Sciences, Jagiellonian University, ul. Oleandry 2a, PL−30−063 Kraków, Poland; Peter Pervesler [[email protected]] Department of Palaeontology, University of Vienna, Althanstrasse 14, A−1090 Vienna, Austria. Introduction fill related to the Southern Alps and Apennines. The Late Pliocene sediments are interpreted as a regressive succession Dactyloidites peniculus, a radial trace fossil, has been de− deposited in the transition from outer to inner shelf (Domi− scribed by D’Alessandro and Bromley (1986) from Pleisto− nici 2001, 2004). -
MAY 2014 VOLUME 41, ISSUE 05 Canadian Publication Mail Contract – 40070050 MORE THAN MAPPING WANT to LIFT YOUR PETREL® WORKFLOWS to NEW HEIGHTS?
20 Fossils Hunting for Provinces 28 Go Take a Hike 34 GeoConvention 2014: Focus 36 Bringing the Cretaceous Sea to Mount Royal University: A Proposal to Fund the East Gate Entrance Fossil Display $10.00 MAY 2014 VOLUME 41, ISSUE 05 Canadian Publication Mail Contract – 40070050 MORE THAN MAPPING WANT TO LIFT YOUR PETREL® WORKFLOWS TO NEW HEIGHTS? Seamlessly bring more data into the fold. Dynamically present your insight like never before. SOFTWARE SERVICES CONNECTIVITY DATA MANAGEMENT The Petrosys Plug-in for Petrel® gives you access to powerful Petrosys mapping, surface modeling and data exchange from right where you need it – inside Petrel. Now you have the power to effortlessly and meticulously bring your critical knowledge together on one potent mapping canvas. Work intuitively with your Petrel knowledge and, should you so require, simultaneously aggregate, map and model data direct from multiple other sources – OpenWorks®, ArcSDE®, IHS™ Kingdom®, PPDM™ and more. Refine, enhance and then present your results in beautiful, compelling detail. The result? Decision-making is accelerated through consistent mapping and surface modeling as focus moves from regional overview through to the field and reservoir scale. To learn more go to www.petrosys.com.au/petrel. Petrel is a registered trademark of Schlumberger Limited and/or its affiliates. OpenWorks is a registered trademark of Halliburton. ESRI trademarks provided under license from ESRI. IHS and Kingdom are trademarks or registered trademarks of IHS, Inc. PPDM is a trademark of the Professional Petroleum Data Management (PPDM) Association. MAY 2014 – VOLUME 41, ISSUE 05 ARTICLES Fossils Hunting for Provinces ..................................................................................................... 20 CSPG OFFICE Tools to Tackle the Riddle of the Sands ............................................................................... -
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Index [Italic page numbers indicate major references] Abajo Mountains, 382, 388 Amargosa River, 285, 309, 311, 322, Arkansas River, 443, 456, 461, 515, Abort Lake, 283 337, 341, 342 516, 521, 540, 541, 550, 556, Abies, 21, 25 Amarillo, Texas, 482 559, 560, 561 Abra, 587 Amarillo-Wichita uplift, 504, 507, Arkansas River valley, 512, 531, 540 Absaroka Range, 409 508 Arlington volcanic field, 358 Acer, 21, 23, 24 Amasas Back, 387 Aromas dune field, 181 Acoma-Zuni scction, 374, 379, 391 Ambrose tenace, 522, 523 Aromas Red Sand, 180 stream evolution patterns, 391 Ambrosia, 21, 24 Arroyo Colorado, 395 Aden Crater, 368 American Falls Lava Beds, 275, 276 Arroyo Seco unit, 176 Afton Canyon, 334, 341 American Falls Reservoir, 275, 276 Artemisia, 21, 24 Afton interglacial age, 29 American River, 36, 165, 173 Ascension Parish, Louisana, 567 aggradation, 167, 176, 182, 226, 237, amino acid ash, 81, 118, 134, 244, 430 323, 336, 355, 357, 390, 413, geochronology, 65, 68 basaltic, 85 443, 451, 552, 613 ratios, 65 beds, 127,129 glaciofluvial, 423 aminostratigraphy, 66 clays, 451 Piedmont, 345 Amity area, 162 clouds, 95 aggregate, 181 Anadara, 587 flows, 75, 121 discharge, 277 Anastasia Formation, 602, 642, 647 layer, 10, 117 Agua Fria Peak area, 489 Anastasia Island, 602 rhyolitic, 170 Agua Fria River, 357 Anchor Silt, 188, 198, 199 volcanic, 54, 85, 98, 117, 129, Airport bench, 421, 423 Anderson coal, 448 243, 276, 295, 396, 409, 412, Alabama coastal plain, 594 Anderson Pond, 617, 618 509, 520 Alamosa Basin, 366 andesite, 75, 80, 489 Ash Flat, 364 Alamosa -