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  • Volume 35 GEUS Bulletin front cover

    Review of Survey activities 2015
    Vol. 35 (2016)

    Editors Adam A. Garde, Ole Bennike, Kristine Thrane and W. Stuart Watt

    This issue of​ Review of Survey Activities presents a selection of 24 papers reflecting the wide spectrum of current activities of the Geological Survey of Denmark and Greenland, from the microscopic to the plate-tectonic level.

    The Survey’s activities in Denmark are illustrated by 11 papers covering widely different subjects including groundwater management, pesticide monitoring, 3D urban geology, the regional Danish potential for geothermal energy, Palaeozoic stratigraphy from borehole logs, enhancement of oil production by injection of ‘smart’ water and glacial geology.

    Activities in Greenland are illustrated by eight papers on Precambrian crustal evolution and mineralisation processes in South-East and northern West Greenland, fundamental magma processes in the Skaergaard intrusion, onshore and offshore seismological studies, and on long-term monitoring of the Greenland ice sheet and sea-ice variability.

    International studies by the Survey are represented by two papers describing a large Nordic CO2-storage project and a pilot study of burial and exhumation along the eastern passive margin of Labrador and Newfoundland using apatite fission track analysis.

    Finally, three papers describe new developments in the digital access to, and handling of Greenland-related geodata and presentation of a new smartphone- and tablet-based app for effective handling of geological and sample data during field work.

     

  • Volume 34 GEUS Bulletin front cover

    The ammonites of the Middle Jurassic Cranocephalites beds of East Greenland
    Vol. 34 (2015)

    John H. Callomon, Peter Alsen & Finn Surlyk

    The Mesozoic sedimentary succession of eastern Greenland is renowned for its Boreal Jurassic ammonite record. The marine Middle Jurassic deposits of the Jameson Land Basin in central East Greenland are particularly rich in ammonites and have been the subject of much detailed taxonomic and stratigraphic study since the first collections at the beginning of the 20th century. Over the last fifty years, much of the work on the Middle Jurassic ammonite faunas has been undertaken by John H. Callomon, working initially under Lauge Koch’s last expeditions and subsequently with the University of Copenhagen and the Geological Survey of Greenland (GGU, now GEUS).

    This bulletin presents the culmination of these endeavours, published after John H. Callomon’s death. It focusses on the so-called Cranocephalites beds of the Ugleelv area of Jameson Land where a detailed ammonite stratigraphy comprising thirty-four faunal horizons is established for the Borealis, Indistinctus and Pompeckji Standard Zones. The Pompeckji Zone is subdivided into four new subzones and four new species are described. This detailed taxonomic and stratigraphic analysis confirms the status of the Jameson Land succession as the key Boreal reference section for this time interval, and furthermore allows a high-resolution study of the evolution of the ammonites which on this time-scale appears to be continuous.

  • Volume 33 GEUS Bulletin front cover

    Review of Survey activities 2014
    Vol. 33 (2015)

    Editors Ole Bennike, Adam A. Garde and W. Stuart Watt

    This Review of Survey activities presents a selection of 20 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microscopic to the plate-tectonic level.

    The Survey’s activities in Denmark are illustrated by eight articles covering Palaeozoic stratigraphy, permeability of North Sea chalk, Quaternary geology, seismology, groundwater geology and an assessment of mineral raw materials.

    Activities in Greenland and the Faroe Islands are also covered by eight papers. One deals with the completed Continental Shelf Project, three with mineral resources and exploration and three papers describe the Survey’s monitoring of the Greenland ice sheet. One paper deals with applied glaciology in Kyrgyzstan, Greenland and Canada.

    The Survey’s international activities are the subject of three papers: two dealing with fingerprinting of heavy minerals in Labrador and Brazil and one dealing with carbon dioxide capture and storage in Europe.

    Finally, one paper describes a new method to develop digital models, e.g. for geological outcrops, based on images taken with a handheld camera.

  • Volume 32 GEUS Bulletin front cover

    A catalogue of Danian gastropods from the Baunekule facies, Faxe Formation, Denmark
    Vol. 32 (2014)

    Bodil W. Lauridsen and K.I. Schnetler

    Fossiliferous middle Danian limestones of the Faxe Formation, exposed in a large quarry on the Stevns peninsula, eastern Denmark, yield a detailed record of the complex ecosystem associated with cold-water coral mounds. A particular sedimentary–diagenetic facies, the Baunekule facies, preserves the faunal record in exceptional detail.

    This bulletin presents a catalogue of the gastropod fauna from the Baunekule facies, providing the taxonomic status of 194 taxa; one new species (Zaclys? nuetzeli) is introduced. The catalogue is fully illustrated with a combination of detailed drawings and photographs, the former produced in the 1960s by Erna Nordmann, Gunni Jørgensen and Betty Engholm under the direction of Professor Alfred Rosenkrantz. The bulletin documents the high diversity of the gastropod fauna and the overwhelming dominance of small (millimetre-sized) carnivorous forms that browsed on the coral substrate. Over 80% of this unusual fauna may be endemic to the Faxe Formation, probably reflecting the specialised nature of the cold-water coral mound ecosystem.

  • Review of Survey activities 2013 Vol 31 cover

    Review of Survey activities 2013
    Vol. 31 (2014)

    Edited by Ole Bennike, Adam A. Garde and W. Stuart Watt

    This Review of Survey activities presents a selection of 22 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microscopic to the plate-tectonic level.

    The Survey's activities in Denmark and surrounding areas are illustrated by 11 articles covering mapping of fractures in Precambrian rocks, shale gas investigations, chalk architecture, a new technique for CO2-flooding experiments of chalk, Cretaceous and Palaeogene biostratigraphy, groundwater geology, Quaternary geology, stormwater management and geothermal energy.

    Activities in Greenland are covered by nine papers, four of which deal with mineral and petroleum exploration. One paper deals with seismology, three papers describe the Survey's monitoring of the Greenland ice sheet and one paper deals with long-term changes of the Upernavik Isstrøm.

    The Survey's activities in the new Center for Minerals and Materials (MiMa) are the subject of one paper, and finally on the occasion of its 125th anniversary in 2013, the Survey's history is briefly described.

     

  • Volume 30 cover page

    Stratigraphic landscape analysis, thermochronology and the episodic development of elevated, passive continental margins
    Vol. 30 (2013)

    Paul F. Green, Karna Lidmar-Bergström, Peter Japsen, Johan M. Bonow and James A. Chalmers

    The uplift histories of passive continental margins constitute an important area of research, first of all because of their worldwide economic importance. Uplift and exhumation control the maturation processes of petroleum in marginal sedimentary basins.

    The histories of subsidence and uplift of passive continental margins are challenging to study and not least to explain in satisfactory ways, and different approaches and schools of thought have developed among different research groups over time.

    The present volume applies stringent landscape analysis and state-of-the-art thermochronology to several passive continental margins around the world. The great importance of relict sedimentary covers in elevated and tilted continental margins is demonstrated, and the strengths and limitations of apatite fission track thermochronology are laid out in detail.

    The authors demonstrate with a pioneering study of the margin of West Greenland and several other case studies that elevated, passive continental margins are not the results of continuous denudation and slow uplift acting on permanent highs. Instead, many margins have experienced complex histories of repeated subsidence, deposition, uplift, tilting and erosion. The nature of these processes is not yet well understood, but the regional extent of the vertical movements documented here suggests a plate-scale control. 

     

  • Volume 29 cover page

    Tectono-magmatic evolution of the younger Gardar southern rift, South Greenland
    Vol. 29 (2013)

    Brian G.J. Upton

    The Mesoproterozoic Gardar province in South Greenland comprises some of the Earth's best exposed and best preserved alkaline intrusive complexes. The province was formed by continental rifting and associated magmatism during a long interval (1300–1140 Ma). Of the two parallel Gardar rift zones, the southern zone underwent a separate evolution during the younger Gardar period (1185–1140 Ma). This bulletin describes this mega-volcanic system with rifting, magma generation, emplacement and crystallisation in giant dykes and central intrusions. The primitive basic magmas evolved by fractionation into extreme compositions, and some intrusions, in particular the famous Ilímaussaq complex, contain accumulations of rare and exotic elements such as zirconium, niobium, rare earths and uranium. Many rocks show spectacular features of igneous layering and accumulation of crystals which recount the processes in the magma chambers. A modern analogue to the Gardar system is the Kenya Rift.

    The author, Brian Upton, has worked with the Gardar province for more than 50 years. His knowledge is based on extensive field work, laboratory studies and comparative studies in other alkaline provinces.

     

  • Volume 28 cover page

    Review of Survey activities 2012
    Vol. 28 (2013)

    Edited by Ole Bennike, Adam A. Garde and W. Stuart Watt

    This Review of Survey activities presents a selection of 17 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microscopic to the plate-tectonic level.

    The Survey's activities in Denmark and surrounding areas are illustrated by nine articles covering Miocene geology, groundwater geology, marine geology, geological mapping, seismology, disposal of radioactive waste and the use of satellite radar data to detect elevation changes.

    Activities in Greenland are covered by seven papers dealing with mineral and petroleum exploration. One paper describes lineament mapping and another describes the Survey's monitoring of the Greenland ice sheet. The Survey's international activities are the subject of a paper dealing with titanium minerals in Cameroon. 

  • Volume 27 cover page

    Neoglacial and historical glacier changes around Kangersuneq fjord in southern West Greenland
    Vol. 27 (2012)

    Anker Weidick, Ole Bennike, Michele Citterio and Niels Nørgaard-Pedersen

    The Greenland ice sheet is losing mass at an accelerating rate due to climate change. Prediction of the future behaviour of the ice sheet depends on our understanding of the links between climatic variations and glacial fluctuations in the distant and recent past. This bulletin presents an overview of glacier fluctuations in south-western Greenland over the last 300 years, with particular focus on the inner parts of Nuup Kangerlua. The early record is based on written descriptions, paintings, photographs and maps of the area from the 1700s and 1800s, together with archaeological data from Norse ruins; aerial photographs and satellite images from the 1900s provide a link to the present.

    The lowland marine outlets from the Inland Ice in south-western Greenland were mainly characterised by large amplitude changes during the Late Holocene, as illustrated in this bulletin by the Kangiata Nunaata Sermia glacier system which has receded over 20 km during the last two centuries, demonstrating a marked response to climatic fluctuations during and since the Little Ice Age. Other examples of such behaviour are provided by the Eqalorutsit Killiit Sermiat glacier at the head of Nordre Sermilik fjord in southern Greenland, and by Jakobshavn Isbræ in Disko Bugt in central West Greenland. In contrast, where uplands and highlands extend below the marginal parts of the Inland Ice, the outlets have been advancing almost up to the present, so that the position of the glacier front around AD 2000 broadly coincides with the Little Ice Age maximum. It is notable, however, that the number of advancing outlets has decreased markedly in recent years.

  • Volume 26 cover page

    Review of Survey activities 2011
    Vol. 26 (2012)

    Edited by Ole Bennike, Adam A. Garde and W. Stuart Watt

    This Review of Survey activities presents a selection of 20 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microscopic to the plate-tectonic level.

    The Survey's activities in Denmark and surrounding areas are illustrated by 11 articles covering petroleum geology, groundwater geology, geomorphology, marine geology, geothermal energy, seismology and monitoring of an underground gas storage.

    Activities in Greenland are covered by five papers dealing with mineral and petroleum exploration. Two other papers describe the Survey's monitoring of the Greenland ice sheet and the testing of an automatic earthquake detection method on data from Station Nord, North Greenland.

    The Survey's international activities are the subject of two papers: one dealing with petroleum geology in Vietnam, one with agrominerals in Tanzania.

  • Volume 25 cover page

    Upper Cretaceous chalk facies and depositional history recorded in the Mona-1 core, Mona Ridge, Danish North Sea
    Vol. 25 (2011)

    ​Kresten Anderskouv and Finn Surlyk

    Upper Cretaceous – Danian chalks form important hydrocarbon reservoirs in the North Sea, contributing significantly to the national economies of Denmark, Norway and the United Kingdom. Understanding the process of chalk sedimentation thus has implications not only for charting the evolution of the Cretaceous chalk sea, but also for predicting the distribution and nature of potential reservoir chalks in the subsurface. In particular, North Sea chalk reservoirs commonly include a range of redeposited chalk facies types, yet rigorous documentation of such facies is scarce in the published literature.

    This bulletin presents a detailed analysis of chalk deposits from an exceptionally well-cored borehole (Mona-1) in the northern Danish Central Graben. Chalk sedimentation in this area in the Late Cretaceous was strongly influenced by active intrabasinal tectonics, controlling sea-floor morphology and the location of depocentres. Chalk ooze was commonly remobilised, creating a wide spectrum of chalk facies types that record processes ranging from suspension settling to slumping and debris flow.

  • Volume 24 cover page

    The East Greenland rifted volcanic margin
    Vol. 24 (2011)

    C. Kent Brooks

    The East Greenland sector of the Palaeogene–Recent North Atlantic Igneous Province is one of the Earth's largest and best exposed igneous manifestations, and it includes the Skaergaard intrusion, probably the most studied igneous body worldwide. This volume contains an introductory historical review, descriptions of the igneous activity and related mineralisation processes in the regions throughout its rifting, spreading, stabilisation and uplift history. Finally, the underlying, plate-tectonic mantle processes are discussed. The text is accompanied by an extensive reference list and an appendix with selected age data from several sources.

    The author, C. Kent Brooks, has an intimate knowledge of the entire region from numerous expeditions and research projects in close collaboration with Danish and international scientists and research students, including three major expeditions of the Danish Lithosphere Centre in 1994–2000.

     

  • Volume 23 cover page

    Review of Survey activities 2010
    Vol. 23 (2011)

    Edited by Ole Bennike, Adam A. Garde and W. Stuart Watt

    This Review of Survey activities presents a selection of 19 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microscopic to the plate-tectonic level.

    The Survey's activities in Denmark and surrounding areas are illustrated by 12 articles covering petroleum geology, groundwater geology, applied marine geology, Quaternary stratigraphy, sea-level changes, disposal of radioactive waste and the use of satellite radar data to detect elevation changes. The depth of two earthquakes has been determined using data from array stations in Canada and Niger.

    Activities in Greenland are covered by six papers dealing with mineral and petroleum exploration. One paper comes with further evidence that the controversial Wegener Fault is a myth. The influence of recent climate change on the Greenland ice sheet is the subject of another article; 2010 was the warmest year ever recorded in Greenland, and the ice sheet is losing mass at an accelerating rate.

    The Survey's international activities are the subject of a paper dealing with quality control of geophysical data in Ghana.

  • Volume 22 cover page

    Lithostratigraphy of the Upper Oligocene – Miocene succession of Denmark
    Vol. 22 (2010)

    Erik Skovbjerg Rasmussen, Karen Dybkjær and Stefan Piasecki

    The Upper Oligocene – Miocene succession of onshore Denmark is about 250 m thick and is composed of interdigitating, coarse-grained fluvio-deltaic and mud-rich marine sediments; it is best exposed in coastal cliffs in eastern and northern Jylland but is also seen locally inland. These sediments contain important natural resources such as brown coals, clays, and sand and gravel deposits (locally rich in heavy minerals), and thus have been the focus of study since the 19th century. In recent years, the growing demand for a reliable source of drinking water has led to renewed interest in the succession. The resultant intensive drilling campaign – over 100 boreholes now penetrate the succession – and high-resolution seismic surveys have made it possible to reconstruct in detail the subsurface architecture of the sedimentary basin and to chart the evolution of the landscape between 25 and 8 million years ago.

    This bulletin presents a revised lithostratigraphy of the Upper Oligocene – Miocene succession of onshore western Denmark. The Upper Oligocene is referred to the Brejning Formation, which is subdivided into two members, one of which is new. The Miocene is subdivided into two new groups: the Ribe and Måde Groups. The former (Lower–Middle Miocene) comprises six formations (two new, four revised) and eight members, six of which are erected here. The Måde Group (Middle–Upper Miocene) consists of four formations, of which two are new lithostratigraphic units.

  • Volume 21 cover page

    Exploration history and place names of northern East Greenland
    Vol. 21 (2010)

    Anthony K. Higgins

    This Bulletin records the exploration history of northern East Greenland in three phases: the pioneer exploration and discovery from c. 2400 BC to 1912; commercial activities, early mountaineering and geological mapping from 1919 to 1960; and modern scientific investigations, adventure and sporting expeditions from 1961 to 2008. The catalogue of place names that forms the bulk of this volume gives the location and origin of more than 5650 approved and unapproved names.

    The early exploration of northern East Greenland was carried out by many different nations, whose objectives varied from seeking a route to the North Pole, searching for missing polar explorers, commercial whaling and sealing to primary exploration and mapping. After the Norwegian–Danish dispute over the sovereignty of parts of East Greenland was settled at the International Court of Justice in The Hague in 1933, the Place Name Committee for Greenland (Stednavneudvalget) was established, and the place names used on existing published maps of Greenland were systematically reviewed and with few exceptions approved in danicised form.

    More than 3000 place names were officially approved by the Place Name Committee for use in northern East Greenland up to the end of 1984, after which responsibility passed to the Home-Rule government at Nuuk in Green- land. More than a third of these place names were proposed by members of the expeditions led by the Danish geologist Lauge Koch. The post-war expeditions led by Lauge Koch were almost entirely geological in nature, and the place names given reflect in part geological characteristics of the features named, the animals encountered and events during the expeditions, as well as commemorating the mountains, lakes and other features of the home countries of the participants. 

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