Geological Survey of Denmark and Greenland Bulletin最新文献

{"title":"The Greenland ice sheet – snowline elevations at the end of the melt seasons from 2000 to 2017","authors":"Robert S. Fausto And the PROMICE team*","doi":"10.34194/geusb.v41.4346","DOIUrl":"https://doi.org/10.34194/geusb.v41.4346","url":null,"abstract":"The Greenland ice sheet has experienced an average mass loss of 142 ± 49 Gt/yr from 1992 to 2011 (Shepherd et al. 2012), making it a significant contributor to sea-level rise. Part of the ice- sheet mass loss is the result of increased dynamic response of outlet glaciers (Rignot et al. 2011). The ice discharge from outlet glaciers can be quantified by coincident measurements of ice velocity and ice thickness (Thomas et al. 2000; van den Broeke et al. 2016). As part of the Programme for monitoring of the Greenland Ice Sheet (PROMICE; Ahlstrøm et al. 2008), three airborne surveys were carried out in 2007, 2011 and 2015, with the aim of measuring the changes in Greenland ice-sheet thicknesses. The purpose of the airborne surveys was to collect data to assess the dynamic mass loss of the Greenland ice sheet (Andersen et al. 2015). Here, we present these datasets of observations from ice-penetrating radar and airborne laser scanning, which, in combination, make us able to determine the ice thickness precisely. Surface-elevation changes between surveys are also presented, although we do not provide an in-depth scientific interpretation of these.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85682622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Base-metal and REE anomalies in lower Palaeozoic sedimentary rocks of Amundsen Land, central North Greenland: implications for Zn-Pb potential","authors":"D. Rosa, J. Slack, H. Falck","doi":"10.34194/geusb.v41.4338","DOIUrl":"https://doi.org/10.34194/geusb.v41.4338","url":null,"abstract":"During the 2013 field season, siliciclastic and carbonate rocks of the lower Palaeozoic sedimentary succession of the Franklinian Basin in Amundsen Land, central North Greenland, were collected for whole-rock geochemical analysis. These data are evaluated here in an attempt to identify possible hydrothermal signatures related to sediment-hosted Zn-Pb mineralisation, similar to that found in correlative strata at the large Citronen Fjord deposit located c. 100 km to the eastnorth-east. In this paper, we use the term Sedex in a broad sense to describe stratiform, sediment-hosted deposits that formed either by syngenetic (exhalative) processes or by subsea-floor replacement coeval with sedimentation (e.g. Emsbo et al. 2016); the term Mississippi Valley-type (MVT) is used for non-stratiform Zn-Pb deposits that formed epigenetically during late diagenesis or tectonism (e.g. Leach et al. 2010).","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88811264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shale fabric and organic nanoporosity in lower Palaeozoic shales, Bornholm, Denmark","authors":"Lucy Malou Henningsen, C. H. Jensen, N. Schovsbo, A. T. Nielsen, G. Pedersen","doi":"10.34194/geusb.v41.4332","DOIUrl":"https://doi.org/10.34194/geusb.v41.4332","url":null,"abstract":"In organic-rich shales, pores form during oil and gas genesis within organic matter (OM) domains. The porosity thus differs markedly from that of conventional reservoir lithologies. Here we present the first description of shale fabric and pore types in the lower Palaeozoic shales on Bornholm, Denmark. The pores have been studied using the focused ion beam scanning electron microscope (FIB-SEM) technique, which allows for high resolution SEM images of ion polished surfaces. Shale porosity is influenced by many factors including depositional fabric, mineralogical composition, diagenesis and oil and gas generation (Schieber 2013). Here we discuss some of these factors based on a study of lower Palaeozoic shale samples from the Billegrav-2 borehole on Bornholm (Fig. 1) undertaken by Henningsen & Jensen (2017). The shales are dry gas-mature (2.3% graptolite reflectance; Petersen et al. 2013) and have been extensively used as analogies for the deeply buried Palaeozoic shales elsewhere in Denmark (Schovsbo et al. 2011; Gautier et al. 2014). The Danish lower Palaeozoic shale gas play was tested by the Vendsyssel-1 well drilled in northern Jylland in 2015. Gas was discovered within a c. 70 m thick gas-mature, organicrich succession (Ferrand et al. 2016). However, the licence was subsequently relinquished, due to a too low gas content. The present study confirms a close similarity of pore development between the shales on Bornholm and in the Vendsys sel-1 indicating a high porosity within this stratigraphic level throughout the subsurface of Denmark. However, the rather different development of porosity in the different shale units presents a hitherto neglected aspect of the Palaeozoic gas play in Denmark.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88905780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Miocene oil-bearing diatom ooze from the North Sea","authors":"E. Sheldon, E. Rasmussen, K. Dybkjær, T. Eidvin, F. Riis, R. Weibel","doi":"10.34194/geusb.v41.4335","DOIUrl":"https://doi.org/10.34194/geusb.v41.4335","url":null,"abstract":"In recent years there has been an increased interest in Neogene hydrocarbon accumulations in the North Sea. The production of gas from Pliocene–Quaternary deposits in the Dutch sector, the discovery of oil-bearing Miocene sands in the Lille John area and oil accumulation in middle Miocene deposits in the T-1 well in the northern part of the Danish Central Graben area, have documented Neogene hydrocarbon accumulations. Some of these deposits are of economic interest. This study presents an oil-bearing, middle Miocene diatom ooze in the Valhall Field (well 2/8-G-2), within the Norwegian sector (Fig. 1). The Valhall Field is located just north of the Danish–Norwegian sector boundary.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82605094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential for brine storage near the gas storage facility at Lille Torup, northern Jylland, Denmark","authors":"Morten Leth Hjuler, M. Andersen, C. M. Nielsen, A. Mathiesen, L. Kristensen, N. Skaarup, L. Nielsen","doi":"10.34194/geusb.v41.4331","DOIUrl":"https://doi.org/10.34194/geusb.v41.4331","url":null,"abstract":"This study is based on a feasibility study for the Danish Energinet. dk to identify potential formations for brine storage near the gas storage facility at Lille Torup, northern Jylland, Denmark (Fig. 1; Hjuler et al. 2017). Located on top of a salt structure, the gas storage facility comprises seven caverns, which have been washed out by circulating water in the salt dome. One cavern contains c. 520.000 m3 of intrusive brine that must be disposed of in order to increase the storage volume for gas. One option is to inject the brine into the subsurface if a target with appropriate storage properties can be identified, but it is a prerequisite that the stored brine does not compromise freshwater reservoirs. Due to cost considerations, the brine storage should be situated within a radius of 50 km of the gas storage facility and at a depth not exceeding 2000 m. Based on the national geothermal research conducted during the last decade, a number of sandy formations are considered potential storage reservoirs (Fig. 2; e.g. Mathiesen et al. 2009; Vosgerau et al. 2016). Around Lille Torup, these include the Bunter Sandstone/Skagerrak, Gassum, Haldager Sand and Frederikshavn formations where the two former formations are discarded due to present-day burial depths exceeding 2000 m. In addition, the Chalk Group is considered a potential storage formation due to its importance as a hydrocarbon reservoir in the North Sea, however, due to risk of leakage to the younger sediments and risk of environmental issues, the chalk was discarded as potential storage zone.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"164 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84273664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentological and glaciotectonic interpretation of georadar data from the margin of the Vig ice-push ridge, NW Sjælland, Denmark","authors":"Cecilie Skovsø Andersen, P. Jakobsen","doi":"10.34194/geusb.v41.4334","DOIUrl":"https://doi.org/10.34194/geusb.v41.4334","url":null,"abstract":"Glaciotectonic deformations often result in a high degree of variability, including glaciotectonic and sedimentary variability. Redeposition of sediments during deformation increases the variability. Ground-penetrating radar (GPR) has proven to be a good method to determine sedimentary structures in glaciofluvial deposits (Olsen & Andreasen 1994; Van Overmeeren 1998) as well as glaciotectonic structures (Busby & Merrit 1999; Overgaard & Jakobsen 2001). Reflection facies analysis (radar facies) is a useful tool in the characterisation and interpretation of deformed sediments (Van Overmeeren 1998; Jakobsen & Overgaard 2002; Lerche et al. 2014). A GPR survey was carried out at Jyderup Skov in Odsherred in north-west Sjælland (Fig. 1). The presence of parallel ridges in the area indicates glaciotectonic deformation. The aim of the GPR study was to map the interior of the ridge complex and to interpret the genesis of the ridges.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"154 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73471379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Initial field activities of the Camp Century Climate Monitoring Programme in Greenland","authors":"W. Colgan, Allan Ø. Pedersen, D. Binder, H. Machguth, J. Abermann, Mike Jayred","doi":"10.34194/geusb.v41.4347","DOIUrl":"https://doi.org/10.34194/geusb.v41.4347","url":null,"abstract":"Camp Century was a military base constructed by the US Army Corps of Engineers in 1959 in the near-surface layers of the Greenland ice sheet at 77.13°N, 61.03°W and 1886 m above sea level (Clark 1965; Fig. 1). The base housed up to 200 military personel and was continuously occupied until 1964. After three years of additional seasonal operation, the base was abandoned with minimal decommissioning in 1967. Recent Danish scholarship has documented the political and military history of Camp Century in detail (Nielsen & Nielsen 2016). In 2016, the Geological Survey of Denmark and Greenland (GEUS) participated in a multi-nation study that presented regional climate simulations that suggested the icesheet surface mass balance at Camp Century may change from net accumulation to net ablation by 2100 under the UN Intergovernmental Panel on Climate Change RCP8.5 ‘business-as-usual’ climate scenario. However, according to Colgan et al. (2016), net accumulation would persist beyond 2100 at Camp Century under the climate-change mitigation characterised by RCP4.5, an approximately ‘Paris Agreement’ climate scenario. In 2017, in response to concerns from the Government of Greenland over the potential to remobilisation of contaminants from Camp Century within the next century, the Government of Denmark established a programme for long-term climate monitoring and detailed one-time surveying of the debris field at Camp Century (Colgan et al. 2017). This report describes the initial field activities of the Camp Century Climate Monitoring Programme in the context of the four programme goals: 1. To continuously monitor relevant climate variables, including the depth to which meltwater percolates, at the Camp Century site. 2. To regularly update annual likelihoods of meltwater interacting with abandoned materials at the Camp Century site over the next century. 3. To map the estimated spatial extent and vertical depth of abandoned wastes across the Camp Century site. 4. To publicly report all findings from the Camp Century Climate Monitoring Programme in a timely manner.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73887944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Initial observations of the shallow geology in Tannis Bugt, Skagerrak, Denmark","authors":"M. Owen, N. H. Witt, Z. Al-Hamdani, N. Nørgaard‐Pedersen, K. Andresen, J. Leth","doi":"10.34194/geusb.v41.4336","DOIUrl":"https://doi.org/10.34194/geusb.v41.4336","url":null,"abstract":"During August 2017, as part of the habitat mapping of Natura2000 areas, a geophysical survey of a large area within the Skagerrak was undertaken by the Geological Survey of Denmark and Greenland. In this article, we use the acquired data to discuss the geology of Tannis Bugt (Fig. 1), a large shallow bay at the north-west coast of Vendsyssel. The bay extends 40 km between Hirtshals in the west and Skagen in the east forming the northern-most Danish Skagerrak coast.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80731746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagenetic impact on reservoir sandstones of the Heno Formation in the Ravn-3 well, Danish Central Graben","authors":"S. Pedersen, R. Weibel, P. Johannessen, N. Schovsbo","doi":"10.34194/geusb.v41.4330","DOIUrl":"https://doi.org/10.34194/geusb.v41.4330","url":null,"abstract":"Oil and gas production from siliciclastic reservoirs has hitherto been in the Danish Central Graben mostly from Palaeogene and Middle Jurassic sandstone. The Ravn field was the first Upper Jurassic field to start operation. The reservoir is composed of sandstone of the Heno Formation. Production takes place at a depth of 4000 m, which makes Ravn the deepest producing field in the Danish North Sea. The Heno Formation mainly consists of marine shoreface deposits, where foreshore, middle and lower shoreface sandstones constitute the primary reservoir. The results of this study of the diagenetic impact on the mineralogical composition, porosity and permeability are presented here. Microcrystalline quartz has preserved porosity in the sandstone, whereas illite, quartz overgrowth and carbonate cement have reduced both porosity and permeability.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"108 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81523758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New programme for climate monitoring at Camp Century, Greenland","authors":"W. Colgan, S. Andersen, D. As, J. Box, S. Gregersen","doi":"10.34194/geusb.v38.4415","DOIUrl":"https://doi.org/10.34194/geusb.v38.4415","url":null,"abstract":"Camp Century was a military base constructed by the US Army Corps of Engineers (USACE) in 1959 in the nearsurface layers of the Greenland ice sheet at 77.13°N and 61.03°W and 1910 metres above sea level (Clark 1965). The c. 55 ha base housed between 85 and 200 soldiers and was continuously occupied until 1964 (Fig.1). Camp Century primarily served as an experimental facility for the USACE to test ice-sheet construction concepts. Recent Danish scholarship has documented the political and military history of Camp Century in substantial detail (Petersen 2007; Nielsen & Nielsen 2016). To summarise, Project Iceworm, the US Army ambition to deploy offensive missiles within the ice sheet, was never realised. After three years of seasonal operation, Camp Century was finally abandoned with minimal decommissioning in 1967. The Government of Denmark has now established a GEUS-led programme for long-term climate monitoring, as well as one-time waste mapping, at Camp Century. Here, we briefly review the historical scientific activities at Camp Century and introduce the future goals of the Camp Century Climate Monitoring Programme. Finally, we discuss the challenges and outlook of climate monitoring and waste mapping at the former military site.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"29 1","pages":"57-60"},"PeriodicalIF":0.0,"publicationDate":"2017-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86476779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}