A Revised Chalk Lithostratigraphic Nomenclature
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The Lithostratigraphy and Biostratigraphy of the Chalk Group (Upper Coniacian 1 to Upper Campanian) at Scratchell’S Bay and Alum Bay, Isle of Wight, UK
Manuscript Click here to view linked References The lithostratigraphy and biostratigraphy of the Chalk Group (Upper Coniacian 1 to Upper Campanian) at Scratchell’s Bay and Alum Bay, Isle of Wight, UK. 2 3 Peter Hopson1*, Andrew Farrant1, Ian Wilkinson1, Mark Woods1 , Sev Kender1 4 2 5 and Sofie Jehle , 6 7 1 British Geological Survey, Sir Kingsley Dunham Centre, Nottingham, NG12 8 5GG. 9 2 10 University of Tübingen, Sigwartstraße 10, 72074 Tübingen, Germany 11 12 * corresponding author [email protected] 13 14 Keywords: Cretaceous, Isle of Wight, Chalk, lithostratigraphy, biostratigraphy, 15 16 17 Abstract 18 19 The Scratchell‟s Bay and southern Alum Bay sections, in the extreme west of the Isle 20 21 of Wight on the Needles promontory, cover the stratigraphically highest Chalk Group 22 formations available in southern England. They are relatively inaccessible, other than 23 by boat, and despite being a virtually unbroken succession they have not received the 24 attention afforded to the Whitecliff GCR (Geological Conservation Review series) 25 site at the eastern extremity of the island. A detailed account of the lithostratigraphy 26 27 of the strata in Scratchell‟s Bay is presented and integrated with macro and micro 28 biostratigraphical results for each formation present. Comparisons are made with 29 earlier work to provide a comprehensive description of the Seaford Chalk, Newhaven 30 Chalk, Culver Chalk and Portsdown Chalk formations for the Needles promontory. 31 32 33 The strata described are correlated with those seen in the Culver Down Cliffs – 34 Whitecliff Bay at the eastern end of the island that form the Whitecliff GCR site. -
Definition of Chalk
1.1: Introduction: 1.1.1: Definition of chalk: Chalk is a soft, white, porous sedimentary carbonate rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite shells (coccoliths) shed from micro-organisms called coccolithophores. Flint (a type of chert unique to chalk) is very common as bands parallel to the bedding or as nodules embedded in chalk. It is probably derived from sponge spicules or other siliceous organisms as water is expelled upwards during compaction. Flint is often deposited around larger fossils such as Echinoidea which may be silicified (i.e. replaced molecule by molecule by flint). Chalk as seen in Cretaceous deposits of Western Europe is unusual among sedimentary limestone in the thickness of the beds. Most cliffs of chalk have very few obvious bedding planes unlike most thick sequences of limestone such as the Carboniferous Limestone or the Jurassic oolitic limestones. This presumably indicates very stable conditions over tens of millions of years. Figure (1-1): Calcium sulphate 1 "Nitzana Chalk curves" situated at Western Negev, Israel are chalk deposits formed at the Mesozoic era's Tethys Ocean Chalk has greater resistance to weathering and slumping than the clays with which it is usually associated, thus forming tall steep cliffs where chalk ridges meet the sea. Chalk hills, known as chalk downland, usually form where bands of chalk reach the surface at an angle, so forming a scarp slope. Because chalk is well jointed it can hold a large volume of ground water, providing a natural reservoir that releases water slowly through dry seasons. -
Oregon Department of Human Services HEALTH EFFECTS INFORMATION
Oregon Department of Human Services Office of Environmental Public Health (503) 731-4030 Emergency 800 NE Oregon Street #604 (971) 673-0405 Portland, OR 97232-2162 (971) 673-0457 FAX (971) 673-0372 TTY-Nonvoice TECHNICAL BULLETIN HEALTH EFFECTS INFORMATION Prepared by: Department of Human Services ENVIRONMENTAL TOXICOLOGY SECTION Office of Environmental Public Health OCTOBER, 1998 CALCIUM CARBONATE "lime, limewater” For More Information Contact: Environmental Toxicology Section (971) 673-0440 Drinking Water Section (971) 673-0405 Technical Bulletin - Health Effects Information CALCIUM CARBONATE, "lime, limewater@ Page 2 SYNONYMS: Lime, ground limestone, dolomite, sugar lime, oyster shell, coral shell, marble dust, calcite, whiting, marl dust, putty dust CHEMICAL AND PHYSICAL PROPERTIES: - Molecular Formula: CaCO3 - White solid, crystals or powder, may draw moisture from the air and become damp on exposure - Odorless, chalky, flat, sweetish flavor (Do not confuse with "anhydrous lime" which is a special form of calcium hydroxide, an extremely caustic, dangerous product. Direct contact with it is immediately injurious to skin, eyes, intestinal tract and respiratory system.) WHERE DOES CALCIUM CARBONATE COME FROM? Calcium carbonate can be mined from the earth in solid form or it may be extracted from seawater or other brines by industrial processes. Natural shells, bones and chalk are composed predominantly of calcium carbonate. WHAT ARE THE PRINCIPLE USES OF CALCIUM CARBONATE? Calcium carbonate is an important ingredient of many household products. It is used as a whitening agent in paints, soaps, art products, paper, polishes, putty products and cement. It is used as a filler and whitener in many cosmetic products including mouth washes, creams, pastes, powders and lotions. -
Geologic Models and Evaluation of Undiscovered Conventional and Continuous Oil and Gas Resources— Upper Cretaceous Austin Chalk, U.S
Geologic Models and Evaluation of Undiscovered Conventional and Continuous Oil and Gas Resources— Upper Cretaceous Austin Chalk, U.S. Gulf Coast Scientific Investigations Report 2012–5159 U.S. Department of the Interior U.S. Geological Survey Front Cover. Photos taken by Krystal Pearson, U.S. Geological Survey, near the old Sprinkle Road bridge on Little Walnut Creek, Travis County, Texas. Geologic Models and Evaluation of Undiscovered Conventional and Continuous Oil and Gas Resources—Upper Cretaceous Austin Chalk, U.S. Gulf Coast By Krystal Pearson Scientific Investigations Report 2012–5159 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2012 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Pearson, Krystal, 2012, Geologic models and evaluation of undiscovered conventional and continuous oil and gas resources—Upper Cretaceous Austin Chalk, U.S. -
Flint and Chert
61 FLINT AND CHERT. By WILLIAM HILL. F.G.S. (Presidential Address, delivered February Srd, 19/1.) CONTE:'l"TS. PAGE I. !)lTRODUCTION. 61 2. T\'PES OF FLINT AND CHERT (CRHACEOUS) 64- 3. VARIETIES OF FLINT FROM FORMATIONS OTHER THAN THE CHALK 69 4. VARIETIES OF CHERT •••" 71 Cherts of the Upper and Lower Greensand. 71 Chert of the Portland Beds. 73 Carboniferous Chert • 76 Chalcedony in Flint . 80 Chert of the Culm Measures 82 5. IMMATURE FLINT AND CHERT 83 6, GENERAL SUMMARY 85 7 CLASSIFICATION OF SILICIOUS CONCRETIONS 93 1. INTRODUCTION. VE RYONE familiar with the White Chalk of England is E also familiar with the nodules of a different substance which are scattered through it. Break one, the fracture will be conchoidal, and it will be found that within a white rind of greater or less thickness is a hard, black, translucent material, possibly with some cloudy patches, which we recognise as flint. How and when the term flint became applied to these nodules in the Chalk is a matter of some obscurity. We know that Early Man recognised the value of flint for offensive, defensive and domestic purposes, and until quite recent years it played no unimportant part in the economies of mankind. The word probably came to us from the Saxon "flinta." It is used six times by the translators of the Authorised Version of the Old and New Testament, though it seems to be applied to rocks of exceptional hardness, and not to be confined to what we know as flint. Virgil, Pliny, and Lucretius use the word silex in connec tion with striking fire. -
A Contribution to the Sheet Explanation of the Ipswich District (Sheet 207): Cretaceous
A contribution to the Sheet Explanation of the Ipswich district (Sheet 207): Cretaceous Integrated Geosurveys (Southern England) Programme Internal Report IR/05/007 BRITISH GEOLOGICAL SURVEY INTEGRATED GEOSURVEYS (SOUTHERN ENGLAND) PROGRAMME INTERNAL REPORT IR/05/007 A contribution to the Sheet Explanation of the Ipswich district (Sheet 207): Cretaceous M A Woods The National Grid and other Ordnance Survey data are used with the permission of the Controller of Her Majesty’s Stationery Office. Ordnance Survey licence number Licence No:100017897/2004. Keywords Cretaceous, Gault Formation, Chalk Group, Lithostratigraphy, Biostratigraphy, Chronostratigraphy. Bibliographical reference WOODS, M A. 2004. A contribution to the Sheet Eplanation of the Ipswich district (Sheet 207): Cretaceous. British Geological Survey Internal Report, IR/05/007. 10pp. Copyright in materials derived from the British Geological Survey’s work is owned by the Natural Environment Research Council (NERC) and/or the authority that commissioned the work. You may not copy or adapt this publication without first obtaining permission. Contact the BGS Intellectual Property Rights Section, British Geological Survey, Keyworth, e-mail [email protected] You may quote extracts of a reasonable length without prior permission, provided a full acknowledgement is given of the source of the extract. © NERC 2004. All rights reserved Keyworth, Nottingham British Geological Survey 2004 BRITISH GEOLOGICAL SURVEY The full range of Survey publications is available from the BGS British Geological Survey offices Sales Desks at Nottingham, Edinburgh and London; see contact details below or shop online at www.geologyshop.com Keyworth, Nottingham NG12 5GG The London Information Office also maintains a reference ? 0115-936 3241 Fax 0115-936 3488 collection of BGS publications including maps for consultation. -
The Skælskør Structure in Eastern Denmark – Wrench-Related Anticline Or Primary Late Cretaceous Seafloor Topography?
The Skælskør structure in eastern Denmark – wrench-related anticline or primary Late Cretaceous seafloor topography? FINN SURLYK, LARS OLE BOLDREEL, HOLGER LYKKE-ANDERSEN & LARS STEMMERIK Surlyk, F., Boldreel, L.O., Lykke-Andersen, H. & Stemmerik, L. 2010-11-11. The Skælskør structure in eastern Denmark – wrench-related anticline or primary Late Cretaceous seafloor topography? © 2010 by Bulletin of the Geological Society of Denmark, Vol. 58, pp. 99–109. iSSn 0011–6297. (www.2dgf.dk/publikationer/bulletin) https://doi.org/10.37570/bgsd-2010-58-08 Sorgenfrei (1951) identified a number of NW–SE oriented highs in the Upper Cretaceous – Danian Chalk Group in eastern Denmark, including the Skælskør structure and interpreted them as anticlinal folds formed by wrenching along what today is known as the Ringkøbing-Fyn High. Recent reflection seismic studies of the Chalk Group in Øresund and Kattegat have shown that similar highs actually represent topographic highs on the Late Cretaceous – Danian seafloor formed by strong contour- parallel bottom currents. Reflection seismic data collected over the Skælskør structure in order to test the hypothesis of Sorgenfrei show that the Base Chalk reflection is relatively flat with only very minor changes in inclination and cut by only a few minor faults. The structure is situated along the northern margin of a high with roots in a narrow basement block, projecting towards the northwest from the Ringkøbing Fyn High into the Danish Basin. The elevated position is maintained due to reduced subsidence as compared with the Danish Basin north of the high. The hypothesis of wrench tectonics as origin can be refuted. -
Identification of Karst Features in the Portsdown Chalk Fm. from Aerial Photography, Dorset, UK
Identification of Karst Features in the Portsdown Chalk Fm. from Aerial Photography, Dorset, UK Morena N Hammer1, Paul D Burley2, Howard D Mooers1 1Department of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN 2Department of Earth Sciences, University of Minnesota, Minneapolis, MN (email: [email protected]) Introduction Cranborne Chase hosts a unique geological and archaeological landscape in south central England. The Chase occupies the chalk downlands underlain by the cretaceous White Chalk Subgroup plateau that extends from the northern Chalke Escarpment, southward across the counties of Dorset, Wiltshire, and Hampshire (Hopson, 2005). In this region, there is extensive archaeological evidence supporting a large Neolithic population in southern central England from approximately 3600-3440 BC (Woodbridge et al., 2013). During the transition from the Mesolithic to the Neolithic at about 4000 BC, there was a significant change in the tools, farming technique, and cultural tradition. Though archaeologically these transitions are significant, there is little to no data available recording the environment that the Neolithic people were living in and how they influenced the landscape through cultivation and related impacts. One site that has yielded an extensive collection of animal and cultural remains during this time period is the excavation of Fir Tree Field Shaft doline (Allen & Green, 1998). Other typical data archives that would be used for paleoenvironmental reconstruction of the Neolithic period, such as lakes or peat fens, do not exist in Cranborne Chase because of the well-drained karst landscape. These karst features developed in the chalk can be excellent paleoenvironmental archives. Chalk, a form of limestone, is developed by the accumulation and lithification of calcium carbonate shells from marine organisms. -
Calcium Carbonate
Right to Know Hazardous Substance Fact Sheet Common Name: CALCIUM CARBONATE Synonyms: Calcium Salt of Carbonic Acid, Chalk CAS Number: 1317-65-3 Chemical Name: Limestone RTK Substance Number: 4001 Date: July 2015 DOT Number: NA Description and Use EMERGENCY RESPONDERS >>>> SEE LAST PAGE Calcium Carbonate is a white to tan odorless powder or Hazard Summary odorless crystals. It is used in human medicine as an antacid, Hazard Rating NJDOH NFPA calcium supplement and food additive. Other uses are HEALTH 1 - agricultural lime and as additive in cement, paints, cosmetics, FLAMMABILITY 0 - dentifrices, linoleum, welding rods, and to remove acidity in REACTIVITY 0 - wine. REACTIVE Hazard Rating Key: 0=minimal; 1=slight; 2=moderate; 3=serious; 4=severe Reasons for Citation When Calcium Carbonate is heated to decomposition, it Calcium Carbonate is on the Right to Know Hazardous emits acrid smoke and irritating vapors. Substance List because it is cited by OSHA, NIOSH, and Calcium Carbonate is incompatible with ACIDS, EPA. ALUMINUM, AMMONIUM SALTS, MAGNESIUM, HYDROGEN, FLUORINE and MAGNESIUM. Calcium Carbonate mixed with magnesium and heated in a current of hydrogen causes a violent explosion. Calcium Carbonate ignites on contact with FLUORINE. Calcium Carbonate contact causes irritation to eyes and skin. SEE GLOSSARY ON PAGE 5. Inhaling Calcium Carbonate causes irritation to nose, throat and respiratory system and can cause coughing. FIRST AID Eye Contact Immediately flush with large amounts of water for at least 15 Workplace Exposure Limits minutes, lifting upper and lower lids. Remove contact OSHA: The legal airborne permissible exposure limit (PEL) is lenses, if worn, while flushing. -
NERR080 Edition 1 Natural England Marine Chalk Characterisation Project
Natural England Research Report NERR080 Natural England marine chalk characterisation project www.gov.uk/natural -england Natural England Research Report NERR080 Natural England marine chalk characterisation project Authors: Charlotte Moffat, Heidi Richardson, Georgina Roberts Published March 2020 This report is published by Natural England under the pen Government Licence - OGLv3.0 for public sector information. You are encouraged to use, and reuse, information subject to certain conditions. For details of the licence visit Copyright. Natural England photographs are only available for non commercial purposes. If any other information such as maps or data cannot be used commercially this will be made clear within the report. ISBN 978-1-78354-527-8 © Natural England 2019 Project details This report should be cited as: MOFFAT, C., RICHARDSON, H., ROBERTS, G. 2019. Natural England marine chalk characterisation project. Natural England Research Reports, Number 080. Project manager Charlotte Moffat Marine Lead Adviser Norfolk Coast and Marine Team Natural England Area 5A, Nobel House, 17 Smith Square London SW1P 3JR [email protected] Acknowledgements We would like to thank all those that helped us by providing site specific information, attending the workshop and providing comments on the report. In particular we would like to thank Dr David H Evans for his invaluable help in developing the geology sections. NATURAL ENGLAND MARINE CHALK CHARACTERISATION PROJECT Executive Summary Chalk is a sedimentary rock largely composed of the skeletons of calcareous nanoplankton, deposited between approximately 100 and 65 million years ago during the Late Cretaceous period. Chalk can be heterogenous, with local conditions and the proportion of clay present at time of deposition responsible for the diversity. -
Geologic Time
MUSEUMS of WESTERN COLORADO EDUCATION Lesson1: Geologic Time This introductory lesson will give students an understanding of geologic time. The goal is to provide a context for the following lessons in terms of when events happened in relation to each other and present day. Student objectives: Students will be able to: Explain how the geologic time scale is used to organize the Earth’s history Design their own geologic time scales Describe major events in Earth’s history Determine how different events in Earth’s history relate to each other NGSS: MS-ESS1-4 Materials: Measuring tape, Sidewalk Chalk, Art Supplies, Major Events in Earth’s History handout, Geologic Timeline Quiz Time: 2-3 class periods Information relevant to geologic time for teachers: Geologic Time Scale Much has happened during the Earth’s 4.6-billion-year history. The geologic time scale is a way to organize the Earth’s past into different units based on events that have taken place. This is done by relating the stratigraphy (rock layers) to radiometric ages (see below). Absolute vs. Relative Dating The numerical (absolute) ages for certain rock layers obtained by using radiometric dating—a method that looks at the proportions of certain radioactive isotopes remaining in a sample. Samples can be either rocks or the fossils themselves. Radiometric dating is a reliable method because the unstable radioactive elements have a known half-life, which is the amount of time it takes for half of the radioactive isotopes to decay. During radioactive decay, the original isotope, called the parent isotope spontaneously converts to a new isotope called the daughter. -
Chalk and Groundwater
Chalk Links in the North Wessex Downs “Chalk Links” Fact Sheets: Geology groups across the region have produced a series of fact sheets explaining how the underlying chalk affects other characteristic features of this unique area including landscape, soils, land use, industry, hydrology & archaeology. Other fact sheets in this series can be downloaded from: www.northwessexdowns.org.uk FACT SHEET: CHALK AND GROUNDWATER What is chalk? Much of the North Wessex Downs is underlain by Chalk. Chalk is a soft white limestone traversed by layers of flint. It consists of minute calcareous shells and shell fragments which are the remains of plankton which floated in clear, sub-tropical seas covering most of Britain during the Upper Cretaceous, between 95 and 65 million years ago. Chalk is a highly porous rock. The microscopic spaces or pores between these particles can soak up enormous quantities of water. We can think of chalk as a giant sponge soaking up rainfall before it has a chance to run off into streams and rivers. Thus, over much of the upland Downs, there is no surface water in the form of ponds or streams. A high resolution image of the tiny chalk particles Chalk and groundwater and the spaces between them. A chalk well can yield more than 10 million litres of water per day, Chalk is the most important aquifer (underground sufficient to provide the needs of about 70,000 storage water system) in southern Britain. The total people at 150 litres per person per day. abstraction of groundwater in the UK, including that used by industry and agriculture, is some 2400 million cubic metres per year.