R. Fausto, D. As, Jens A. Antoft, J. Box, W. Colgan, S. Andersen, A. Ahlstrøm, M. L. Andersen, M. Citterio, Charalampos Charalampidis, K. Edelvang, K. Haubner, S. H. Larsen, M. Veicherts, A. Weidick
The Greenland ice sheet is an excellent observatory for global climate change. Meltwater from the 1.8 million km2 large ice sheet infl uences oceanic temperature and salinity, nutrient fl uxes and global sea level (IPCC 2013). Surface refl ectivity is a key driver of surface melt rates (Box et al. 2012). Mapping of diff erent ice-sheet surface types provides a clear indicator of where changes in ice-sheet surface refl ectivity are most prominent. Here, we present an updated version of a surface classifi cation algorithm that utilises NASA’s Moderateresolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite to systematically monitor ice-sheet surface melt (Fausto et al. 2007). Our aim is to determine the areal extent of three surface types over the 2000–2014 period: glacier ice, melting snow (including percolation areas) and dry snow (Cuff ey & Paterson 2010). Monthly 1 km2 resolution surface-type grids can be downloaded via the CryoClim internet portal (www.cryoclim.net). In this report, we briefl y describe the updated classifi cation algorithm, validation of surface types and inter-annual variability in surface types.
格陵兰冰盖是全球气候变化的绝佳观测站。180万平方公里大冰盖的融水影响海洋温度和盐度、营养物通量和全球海平面(IPCC 2013)。表面反射率是表面融化速率的关键驱动因素(Box et al. 2012)。不同冰盖表面类型的制图提供了一个明确的指标,表明冰盖表面反射率变化最显著的地方。在这里,我们提出了一种更新版本的地表分类算法,该算法利用NASA Terra卫星上的中分辨率成像光谱仪(MODIS)传感器系统地监测冰盖表面融化(Fausto et al. 2007)。我们的目标是确定2000-2014年期间三种地表类型的面积范围:冰川冰、融雪(包括渗透区域)和干雪(Cuff & Paterson 2010)。每月1平方公里分辨率的曲面型网格可通过CryoClim互联网门户网站(www.cryoclim.net)下载。在本报告中,我们简要介绍了更新的分类算法、地表类型的验证和地表类型的年际变化。
{"title":"Greenland ice sheet melt area from MODIS (2000–2014)","authors":"R. Fausto, D. As, Jens A. Antoft, J. Box, W. Colgan, S. Andersen, A. Ahlstrøm, M. L. Andersen, M. Citterio, Charalampos Charalampidis, K. Edelvang, K. Haubner, S. H. Larsen, M. Veicherts, A. Weidick","doi":"10.34194/GEUSB.V33.4498","DOIUrl":"https://doi.org/10.34194/GEUSB.V33.4498","url":null,"abstract":"The Greenland ice sheet is an excellent observatory for global climate change. Meltwater from the 1.8 million km2 large ice sheet infl uences oceanic temperature and salinity, nutrient fl uxes and global sea level (IPCC 2013). Surface refl ectivity is a key driver of surface melt rates (Box et al. 2012). Mapping of diff erent ice-sheet surface types provides a clear indicator of where changes in ice-sheet surface refl ectivity are most prominent. Here, we present an updated version of a surface classifi cation algorithm that utilises NASA’s Moderateresolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite to systematically monitor ice-sheet surface melt (Fausto et al. 2007). Our aim is to determine the areal extent of three surface types over the 2000–2014 period: glacier ice, melting snow (including percolation areas) and dry snow (Cuff ey & Paterson 2010). Monthly 1 km2 resolution surface-type grids can be downloaded via the CryoClim internet portal (www.cryoclim.net). In this report, we briefl y describe the updated classifi cation algorithm, validation of surface types and inter-annual variability in surface types.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75456973","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}
Pub Date : 2019-12-20DOI: 10.34194/geusb-201943-03-03
Rune J. Clausen, P. Kalvig, J. Nedenskov
The UN Sustainable Development Goal 12, regarding responsible production and consumption of raw materials, guides ongoing international efforts to enhance sustainability in all parts of the mineral sector. Of particular interest, is improving the recyclability of secondary waste streams and thereby increasing the efficiency of recycling end-of-life products. Municipal solid waste – residual waste from household and industry – constitutes one of these secondary streams. It is typically incinerated in waste-to-energy plants producing two types of waste streams that carry a raw material resource potential: incinerator bottom ash (IBA) and incinerator fly ash (IFA). IBA is of particular interest in the recycling industry, where it is commonly recycled to produce three main fractions: (i) ferrous material, (ii) non-ferrous material, and (iii) residual slag. In most cases the two metal fractions are separated further downstream in the value chain, prior to smelting. The residual, non-magnetic fraction (typically 0–45 mm) is used mainly as construction aggregate. Improvements in the efficiency of existing separation technologies are still being made, but less effort is focussed on characterising the fundamental composition and mineral resource potential of IBA. For this reason, the Urban-X project was launched by the Geological Survey of Denmark and Greenland (GEUS) to characterise the composition and resource potential of various waste streams at Amager Bakke waste-to-energy plant in Copenhagen, Denmark. This paper discusses some of the main outcomes of the Urban-X project with respect to IBA, and a full analysis of all waste streams analysed at Amager Bakke is available in Clausen et al. 2019.
联合国可持续发展目标12关于负责任的原材料生产和消费,指导着国际社会为加强矿产部门所有部分的可持续性而正在进行的努力。特别令人感兴趣的是提高二级废物流的可回收性,从而提高回收寿命结束产品的效率。城市固体废物——来自家庭和工业的残余废物——构成了这些次级流之一。它通常在垃圾焚烧发电厂进行焚烧,产生两种具有原料资源潜力的废物流:焚化炉底灰(IBA)和焚化炉飞灰(IFA)。IBA对回收工业特别感兴趣,在那里它通常被回收生产三个主要部分:(i)含铁材料,(ii)有色材料,和(iii)残余渣。在大多数情况下,在冶炼之前,这两种金属馏分在价值链的下游进一步分离。剩余的非磁性部分(通常为0-45毫米)主要用作建筑骨料。目前仍在改进现有分离技术的效率,但较少着重于确定溴化钡的基本组成和矿物资源潜力。因此,Urban-X项目由丹麦和格陵兰地质调查局(GEUS)发起,旨在描述丹麦哥本哈根Amager Bakke废物能源厂各种废物流的组成和资源潜力。本文讨论了Urban-X项目在IBA方面的一些主要成果,并在Clausen et al. 2019中对Amager Bakke分析的所有废物流进行了全面分析。
{"title":"Characterisation of incinerator bottom ash from a Danish waste-to-energy plant: a step towards closing the material cycle","authors":"Rune J. Clausen, P. Kalvig, J. Nedenskov","doi":"10.34194/geusb-201943-03-03","DOIUrl":"https://doi.org/10.34194/geusb-201943-03-03","url":null,"abstract":"The UN Sustainable Development Goal 12, regarding responsible production and consumption of raw materials, guides ongoing international efforts to enhance sustainability in all parts of the mineral sector. Of particular interest, is improving the recyclability of secondary waste streams and thereby increasing the efficiency of recycling end-of-life products. Municipal solid waste – residual waste from household and industry – constitutes one of these secondary streams. It is typically incinerated in waste-to-energy plants producing two types of waste streams that carry a raw material resource potential: incinerator bottom ash (IBA) and incinerator fly ash (IFA). IBA is of particular interest in the recycling industry, where it is commonly recycled to produce three main fractions: (i) ferrous material, (ii) non-ferrous material, and (iii) residual slag. In most cases the two metal fractions are separated further downstream in the value chain, prior to smelting. The residual, non-magnetic fraction (typically 0–45 mm) is used mainly as construction aggregate. Improvements in the efficiency of existing separation technologies are still being made, but less effort is focussed on characterising the fundamental composition and mineral resource potential of IBA. For this reason, the Urban-X project was launched by the Geological Survey of Denmark and Greenland (GEUS) to characterise the composition and resource potential of various waste streams at Amager Bakke waste-to-energy plant in Copenhagen, Denmark. This paper discusses some of the main outcomes of the Urban-X project with respect to IBA, and a full analysis of all waste streams analysed at Amager Bakke is available in Clausen et al. 2019.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82225721","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}
Pub Date : 2019-08-07DOI: 10.34194/GEUSB-201943-00-01
F. Christiansen
Every four years the Geological Survey of Denmark and Greenland (GEUS) develops and implements new strategies to ensure that we are able to help meet the ever-changing challenges that face society. In 2018 these discussions were shaped by important issues like climate change and climate adaptation, and their consequences for our use of energy, minerals and water resources. As part of this strategic focus, GEUS introduced a new publication strategy in 2018 that seeks to increase our publication rate of high impact science, and to gain more visibility within the international scientific community and the media. Many different tools will be applied to make such a long-term cultural change possible, including modernisation of GEUS’ own publication series.
{"title":"Review of Survey activities 2018","authors":"F. Christiansen","doi":"10.34194/GEUSB-201943-00-01","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-00-01","url":null,"abstract":"Every four years the Geological Survey of Denmark and Greenland (GEUS) develops and implements new strategies to ensure that we are able to help meet the ever-changing challenges that face society. In 2018 these discussions were shaped by important issues like climate change and climate adaptation, and their consequences for our use of energy, minerals and water resources. As part of this strategic focus, GEUS introduced a new publication strategy in 2018 that seeks to increase our publication rate of high impact science, and to gain more visibility within the international scientific community and the media. Many different tools will be applied to make such a long-term cultural change possible, including modernisation of GEUS’ own publication series.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85410174","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}
Pub Date : 2019-07-29DOI: 10.34194/GEUSB-201943-03-02
B. Heincke, R. Jackisch, A. Saartenoja, Heikki Salmirinne, Sönke Rapp, R. Zimmermann, M. Pirttijärvi, Erik Vest Sörensen, R. Gloaguen, Lisa Ek, Johan Bergström, A. Karinen, S. Salehi, Y. Madriz, M. Middleton
The use of Unmanned Aerial Systems (UAS), also known as drones, is becoming increasingly important for geological applications. Thanks to lower operational costs and ease of use, UAS offer an alternative approach to aircraft-based and ground-based geoscientific measurements (Colomina & Molina 2014). Magnetic and hyperspectral UAS surveys hold particular promise for mineral exploration, and several groups have recently published studies of magnetic data collected by UAS for such applications (Malehmir et al. 2017; Cunningham et al. 2018), although equivalent studies using hyperspectral data are still rare (Kirsch et al. 2018). Combining both techniques is particularly useful. Magnetic measurements play an important role in mineral exploration, since magnetisation in rocks is mainly associated with magnetite and other iron minerals, which can be used in mapping and targeting of mineral deposits (Dentith & Mudge 2014). Hyperspectral imaging (HSI) is a powerful exploration and mapping technique in areas where the rock surface is well-exposed, and where geological units and mineral compositions can be estimated from spectral features of the electromagnetic spectrum in the visual and infrared range.
无人驾驶航空系统(UAS),也被称为无人机,在地质应用中变得越来越重要。由于操作成本较低且易于使用,无人机系统为基于飞机和地面的地球科学测量提供了一种替代方法(Colomina & Molina 2014)。磁性和高光谱UAS调查对矿产勘探具有特别的希望,最近有几个小组发表了UAS为此类应用收集的磁性数据的研究(Malehmir等人,2017;Cunningham et al. 2018),尽管使用高光谱数据的等效研究仍然很少(Kirsch et al. 2018)。结合这两种技术特别有用。磁性测量在矿产勘探中发挥着重要作用,因为岩石中的磁化主要与磁铁矿和其他铁矿物有关,可用于绘制和定位矿床(Dentith & Mudge 2014)。高光谱成像(HSI)是一种强大的勘探和测绘技术,用于岩石表面暴露良好的地区,在这些地区,地质单元和矿物成分可以从可见光和红外范围内的电磁波谱特征估计出来。
{"title":"Developing multi-sensor drones for geological mapping and mineral exploration: setup and first results from the MULSEDRO project","authors":"B. Heincke, R. Jackisch, A. Saartenoja, Heikki Salmirinne, Sönke Rapp, R. Zimmermann, M. Pirttijärvi, Erik Vest Sörensen, R. Gloaguen, Lisa Ek, Johan Bergström, A. Karinen, S. Salehi, Y. Madriz, M. Middleton","doi":"10.34194/GEUSB-201943-03-02","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-03-02","url":null,"abstract":"The use of Unmanned Aerial Systems (UAS), also known as drones, is becoming increasingly important for geological applications. Thanks to lower operational costs and ease of use, UAS offer an alternative approach to aircraft-based and ground-based geoscientific measurements (Colomina & Molina 2014). Magnetic and hyperspectral UAS surveys hold particular promise for mineral exploration, and several groups have recently published studies of magnetic data collected by UAS for such applications (Malehmir et al. 2017; Cunningham et al. 2018), although equivalent studies using hyperspectral data are still rare (Kirsch et al. 2018). Combining both techniques is particularly useful. Magnetic measurements play an important role in mineral exploration, since magnetisation in rocks is mainly associated with magnetite and other iron minerals, which can be used in mapping and targeting of mineral deposits (Dentith & Mudge 2014). Hyperspectral imaging (HSI) is a powerful exploration and mapping technique in areas where the rock surface is well-exposed, and where geological units and mineral compositions can be estimated from spectral features of the electromagnetic spectrum in the visual and infrared range.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87568306","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}
Pub Date : 2019-07-22DOI: 10.34194/GEUSB-201943-02-04
Graham J. Banks, S. Bernstein, S. Salehi, P. Guarnieri, D. Bird, Catherine Hamblett, D. Peacock, J. Foster
Basement highs are large structural features, commonly buried in sedimentary basins (Busby & Azor 2012). They are of interest for natural resources exploration and research because of their ability to influence migration and entrapment of petroleum (Trice 2014) and water, and the deposition of metals (Hitzman 2005; Borg et al. 2012). Three-dimensional (3D) reservoir models (e.g. Shepherd 2009) are built to evaluate and model fluid-filled basement reservoirs (Ringrose & Bentley 2015). However, subsurface data are expensive, difficult to obtain and are often widely spaced. Ideally, basement reservoir models would be constrained by rock, fracture and mineral vein data from appropriate outcrop analogues (acknowledging that subaerial basement rocks have, by definition, a different uplift history than subsurface basement). The Liverpool Land Basement High (LLBH) in Greenland is an uplifted and well-exposed basement high located between two sedimentary basins, and thus provides a valuable analogue for fractured basement-hosted mineral, oil and geothermal reservoirs. The Geological Survey of Denmark and Greenland (GEUS) conducted reconnaissance work on the LLBH in 2018 to assess the quality of the exposure of basement palaeo-weathering profiles and fault-fracture networks. Here, we introduce the LLBH, the concept of fractured basement reservoir modelling, and how studying the LLBH can help enhance reservoir modelling of fractured basement. We present some of our preliminary observations of LLBH fault-fracture networks and discuss how the exposed sediment-basement features and processes might aid industry and research in their top basement mapping activities. We propose that LLBH provides a particularly suitable analogue for industry and research to analyse: (a) multiscale fracture system connectivity, (b) fluid migration and fluid-rock reaction processes, (c) input parameters for basement reservoir modelling and (d) top basement geomorphologies and processes.
{"title":"Liverpool Land Basement High, Greenland: visualising inputs for fractured crystalline basement reservoir models","authors":"Graham J. Banks, S. Bernstein, S. Salehi, P. Guarnieri, D. Bird, Catherine Hamblett, D. Peacock, J. Foster","doi":"10.34194/GEUSB-201943-02-04","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-02-04","url":null,"abstract":"Basement highs are large structural features, commonly buried in sedimentary basins (Busby & Azor 2012). They are of interest for natural resources exploration and research because of their ability to influence migration and entrapment of petroleum (Trice 2014) and water, and the deposition of metals (Hitzman 2005; Borg et al. 2012). Three-dimensional (3D) reservoir models (e.g. Shepherd 2009) are built to evaluate and model fluid-filled basement reservoirs (Ringrose & Bentley 2015). However, subsurface data are expensive, difficult to obtain and are often widely spaced. Ideally, basement reservoir models would be constrained by rock, fracture and mineral vein data from appropriate outcrop analogues (acknowledging that subaerial basement rocks have, by definition, a different uplift history than subsurface basement). The Liverpool Land Basement High (LLBH) in Greenland is an uplifted and well-exposed basement high located between two sedimentary basins, and thus provides a valuable analogue for fractured basement-hosted mineral, oil and geothermal reservoirs. \u0000The Geological Survey of Denmark and Greenland (GEUS) conducted reconnaissance work on the LLBH in 2018 to assess the quality of the exposure of basement palaeo-weathering profiles and fault-fracture networks. Here, we introduce the LLBH, the concept of fractured basement reservoir modelling, and how studying the LLBH can help enhance reservoir modelling of fractured basement. We present some of our preliminary observations of LLBH fault-fracture networks and discuss how the exposed sediment-basement features and processes might aid industry and research in their top basement mapping activities. We propose that LLBH provides a particularly suitable analogue for industry and research to analyse: (a) multiscale fracture system connectivity, (b) fluid migration and fluid-rock reaction processes, (c) input parameters for basement reservoir modelling and (d) top basement geomorphologies and processes.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78882970","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}
Pub Date : 2019-07-22DOI: 10.34194/GEUSB-201943-03-01
C. Knudsen, M. Sønderholm, Tjerk C. Heijboer, J. Kristensen, D. Bering
The amount of provenance information available for onshore and offshore sedimentary deposits in the North Atlantic Region is substantial and rapidly increasing. These data provide an improved understanding of reservoir geology (quality, diagenetic issues, regional source-to-sink relations and local stratigraphic correlations), and thereby can reduce hydrocarbon exploration risk. As such, the number of proprietary, industry-related and public research provenance studies has increased considerably in recent years, and the development and use of new analytical techniques has also caused a surge in the number of grains, isotopes and chemical elements analysed in each study. As a result, it is today close to impossible for the individual researcher or petroleum geologist to draw on all existing provenance data. And the vast expansion of data availability demands new and better methods to analyse and visualise large amounts of data in a systematic way To this end, the Geological Survey of Denmark and Greenland (GEUS) and the Norwegian Petroleum Directorate (NPD) have established a web-based database of provenance data for the North Atlantic area: the North Atlantic Provenance Database. Construction of the database was funded jointly by GEUS and NPD. Future maintenance and further development will be funded by the petroleum industry by subscription to the database. Here, we provide a brief introduction to the database and its future development and expansion. We highlight the current capabilities with an example from East Greenland.
{"title":"The North Atlantic Provenance Database: an introduction","authors":"C. Knudsen, M. Sønderholm, Tjerk C. Heijboer, J. Kristensen, D. Bering","doi":"10.34194/GEUSB-201943-03-01","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-03-01","url":null,"abstract":"The amount of provenance information available for onshore and offshore sedimentary deposits in the North Atlantic Region is substantial and rapidly increasing. These data provide an improved understanding of reservoir geology (quality, diagenetic issues, regional source-to-sink relations and local stratigraphic correlations), and thereby can reduce hydrocarbon exploration risk. As such, the number of proprietary, industry-related and public research provenance studies has increased considerably in recent years, and the development and use of new analytical techniques has also caused a surge in the number of grains, isotopes and chemical elements analysed in each study. As a result, it is today close to impossible for the individual researcher or petroleum geologist to draw on all existing provenance data. And the vast expansion of data availability demands new and better methods to analyse and visualise large amounts of data in a systematic way \u0000To this end, the Geological Survey of Denmark and Greenland (GEUS) and the Norwegian Petroleum Directorate (NPD) have established a web-based database of provenance data for the North Atlantic area: the North Atlantic Provenance Database. Construction of the database was funded jointly by GEUS and NPD. Future maintenance and further development will be funded by the petroleum industry by subscription to the database. Here, we provide a brief introduction to the database and its future development and expansion. We highlight the current capabilities with an example from East Greenland.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"1974 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90225558","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}
Pub Date : 2019-07-22DOI: 10.34194/GEUSB-201943-01-03
M. T. Nielsen, R. Weibel, J. Therkelsen, H. Friis
High porosity is a key factor for good reservoir sandstones for both hydrocarbon and geothermal energy exploitation. The porosity of sandstones generally decreases with increased burial depth due to compaction and cementation. However, some sandstones in the North Sea show higher porosity than expected for their burial depth, due to the presence of microquartz coatings (e.g. Aase et al. 1996; Hendry & Trewin 1995; Jahren & Ramm 2000; Maast et al. 2011). Siliceous sponge spicules have been documented to be an internal source of silica that promotes microquartz coatings (e.g. Hendry & Trewin 1995; Aase et al. 1996). Siliceous sponge spicules, the solid ‘skeleton’ of sponges, consist of opal-A and will dissolve when exposed to higher temperatures, thereby causing supersaturation of the formation water with respect to opal-CT and quartz, resulting in nucleation of numerous small (1–5 µm) quartz crystals (Williams et al. 1985; Hendry & Trewin 1995). To predict reservoir quality it is important to understand the distribution of porosity-preserving microquartz in clastic deposits, and yet this is still poorly understood. To address this, our study presents petrographical analyses of cored sandstone sections from wells of various depositional environments, including back-barrier, estuarine, shoreface and gravity flows, as well as various present-day burial depths across the Danish Central Graben.
高孔隙度是油气和地热能开发的关键因素。由于压实作用和胶结作用,砂岩孔隙度一般随埋深的增加而减小。然而,由于存在微石英涂层,北海的一些砂岩显示出比其埋藏深度更高的孔隙度(例如Aase等人,1996;Hendry & Trewin 1995;Jahren & Ramm 2000;Maast et al. 2011)。硅海绵针状体已被证明是促进微石英涂层的二氧化硅的内部来源(例如Hendry & Trewin 1995;Aase et al. 1996)。硅质海绵微粒是海绵的固体“骨架”,由蛋白石- a组成,在高温下会溶解,从而导致地层水相对于蛋白石- ct和石英的过饱和,导致许多小的(1-5微米)石英晶体成核(Williams et al. 1985;Hendry & Trewin 1995)。为了预测储层质量,了解碎屑沉积中保持孔隙度的微石英的分布是很重要的,但这方面的了解仍然很少。为了解决这个问题,我们的研究展示了从不同沉积环境的井中提取的岩心砂岩剖面的岩石学分析,包括后屏障、河口、滨面和重力流,以及跨越丹麦中央地堑的各种现代埋藏深度。
{"title":"Distribution of porosity-preserving microquartz coatings in sandstones, Upper Jurassic Danish Central Graben","authors":"M. T. Nielsen, R. Weibel, J. Therkelsen, H. Friis","doi":"10.34194/GEUSB-201943-01-03","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-01-03","url":null,"abstract":"High porosity is a key factor for good reservoir sandstones for both hydrocarbon and geothermal energy exploitation. The porosity of sandstones generally decreases with increased burial depth due to compaction and cementation. However, some sandstones in the North Sea show higher porosity than expected for their burial depth, due to the presence of microquartz coatings (e.g. Aase et al. 1996; Hendry & Trewin 1995; Jahren & Ramm 2000; Maast et al. 2011). Siliceous sponge spicules have been documented to be an internal source of silica that promotes microquartz coatings (e.g. Hendry & Trewin 1995; Aase et al. 1996). Siliceous sponge spicules, the solid ‘skeleton’ of sponges, consist of opal-A and will dissolve when exposed to higher temperatures, thereby causing supersaturation of the formation water with respect to opal-CT and quartz, resulting in nucleation of numerous small (1–5 µm) quartz crystals (Williams et al. 1985; Hendry & Trewin 1995). To predict reservoir quality it is important to understand the distribution of porosity-preserving microquartz in clastic deposits, and yet this is still poorly understood. To address this, our study presents petrographical analyses of cored sandstone sections from wells of various depositional environments, including back-barrier, estuarine, shoreface and gravity flows, as well as various present-day burial depths across the Danish Central Graben.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81413339","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}
Pub Date : 2019-07-17DOI: 10.34194/GEUSB-201943-02-05
S. Salehi, Christian Mielke, C. B. Pedersen, S. D. Olsen
Spaceborne remote sensing is a suitable tool for early mineral exploration and surveying large areas of high Arctic environment in a fast and cost-effective manner. While spaceborne data have been used widely to map geology in arid areas, similar approaches for remotely-sensed geological mapping of Arctic environments is yet to be developed. Freely available spaceborne optical data provides detailed information of high-quality that could potentially reduce resource exploration risk in remote regions. To this end, this study compares the use of two different multispectral spaceborne datasets (i.e. the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Sentinel-2) to map geological units in and around Wollaston Forland, North-East Greenland – an area rich in Jurassic and Cretaceous sedimentary rocks and important targets for offshore petroleum exploration. Multispectral image sensors simultaneously capture image data within multiple wavelength ranges (bands) across the electromagnetic spectrum. Each band is commonly described by the band number and the band wavelength centre position. Here, we identify the bands most suitable for geological mapping in an Arctic setting, using the Wollaston Forland area as an example. We compare the results obtained by processing spaceborne data with a published geological map for the area (Henriksen 2003).
{"title":"Comparison of ASTER and Sentinel-2 spaceborne datasets for geological mapping: a case study from North-East Greenland","authors":"S. Salehi, Christian Mielke, C. B. Pedersen, S. D. Olsen","doi":"10.34194/GEUSB-201943-02-05","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-02-05","url":null,"abstract":"Spaceborne remote sensing is a suitable tool for early mineral exploration and surveying large areas of high Arctic environment in a fast and cost-effective manner. While spaceborne data have been used widely to map geology in arid areas, similar approaches for remotely-sensed geological mapping of Arctic environments is yet to be developed. Freely available spaceborne optical data provides detailed information of high-quality that could potentially reduce resource exploration risk in remote regions. To this end, this study compares the use of two different multispectral spaceborne datasets (i.e. the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Sentinel-2) to map geological units in and around Wollaston Forland, North-East Greenland – an area rich in Jurassic and Cretaceous sedimentary rocks and important targets for offshore petroleum exploration. Multispectral image sensors simultaneously capture image data within multiple wavelength ranges (bands) across the electromagnetic spectrum. Each band is commonly described by the band number and the band wavelength centre position. Here, we identify the bands most suitable for geological mapping in an Arctic setting, using the Wollaston Forland area as an example. We compare the results obtained by processing spaceborne data with a published geological map for the area (Henriksen 2003).","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75276653","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}
Pub Date : 2019-07-17DOI: 10.34194/GEUSB-201943-01-04
H. Holmslykke, N. Schovsbo, L. Kristensen, R. Weibel, L. Nielsen
The Danish subsurface contains several sandstone units, which represent a large geothermal resource (Vosgerau et al. 2016). Currently, only three geothermal plants are operating in Denmark, but several exploration licences are expected to be awarded in 2019. Geothermal energy is exploited from deeply buried porous sandstones by bringing warm formation water (brine) to the surface, extracting the heat and returning the cooled water to the same sandstones. The reduced temperature of the brine during this process implies a risk of scaling, which may reduce reservoir permeability and hence injectivity. Predicting the chemical composition of formation waters, however, could help to reduce the risk associated with scaling in planned geothermal facilities. Here, we present a regional overview of the geochemistry of brines from deep Mesozoic sandstones in the Danish Basin and North German Basin that supplements previous studies, notably by Laier (2002, 2008). The brine composition at shallow burial typically reflects the original (connate) formation water chemistry, which is determined by the original depositional environment of the sandstone, for example fluvial or marine. However, the mineralogical composition of the sandstone changes during burial, whereby some minerals may dissolve or precipitate when exposed to higher temperatures. These mineral changes are reflected in the brine composition, which typically becomes more saline with increased burial (e.g. Laier 2008; Kharaka & Hanor 2003). The brine chemistry reported here shows a distinct depth trend, which reflects original connate formation waters that are modified through burial diagenesis. We have classified the brines into brine types, which are shown to be related to their depositional environment, depth, geological formation and geographical domains.
丹麦地下包含几个砂岩单元,代表着巨大的地热资源(Vosgerau et al. 2016)。目前,丹麦只有三个地热发电厂在运营,但预计2019年将颁发几个勘探许可证。地热能是从深埋的多孔砂岩中开采的,通过将温暖的地层水(盐水)带到地表,提取热量并将冷水返回到相同的砂岩中。在此过程中,盐水温度的降低意味着结垢的风险,这可能会降低储层的渗透率,从而降低注入能力。然而,预测地层水的化学成分可以帮助减少与计划中的地热设施结垢有关的风险。本文对丹麦盆地和北德盆地中生代深部砂岩的卤水地球化学进行了区域综述,补充了以往的研究,特别是莱尔(2002年、2008年)的研究。浅埋层的卤水组成通常反映原始(合生)地层水化学,这是由砂岩的原始沉积环境(如河流或海洋)决定的。然而,砂岩的矿物组成在埋藏过程中发生了变化,因此,当暴露于较高的温度时,一些矿物质可能会溶解或沉淀。这些矿物变化反映在盐水组成中,通常随着埋藏的增加而变得更咸(例如,Laier 2008;Kharaka & Hanor 2003)。本文报道的卤水化学显示出明显的深度变化趋势,反映了原始的合生地层水经过埋藏成岩作用的改造。根据其沉积环境、沉积深度、地质构造和地理域的不同,将其划分为不同的卤水类型。
{"title":"Characterising brines in deep Mesozoic sandstone reservoirs, Denmark","authors":"H. Holmslykke, N. Schovsbo, L. Kristensen, R. Weibel, L. Nielsen","doi":"10.34194/GEUSB-201943-01-04","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-01-04","url":null,"abstract":"The Danish subsurface contains several sandstone units, which represent a large geothermal resource (Vosgerau et al. 2016). Currently, only three geothermal plants are operating in Denmark, but several exploration licences are expected to be awarded in 2019. Geothermal energy is exploited from deeply buried porous sandstones by bringing warm formation water (brine) to the surface, extracting the heat and returning the cooled water to the same sandstones. The reduced temperature of the brine during this process implies a risk of scaling, which may reduce reservoir permeability and hence injectivity. Predicting the chemical composition of formation waters, however, could help to reduce the risk associated with scaling in planned geothermal facilities. \u0000Here, we present a regional overview of the geochemistry of brines from deep Mesozoic sandstones in the Danish Basin and North German Basin that supplements previous studies, notably by Laier (2002, 2008). The brine composition at shallow burial typically reflects the original (connate) formation water chemistry, which is determined by the original depositional environment of the sandstone, for example fluvial or marine. However, the mineralogical composition of the sandstone changes during burial, whereby some minerals may dissolve or precipitate when exposed to higher temperatures. These mineral changes are reflected in the brine composition, which typically becomes more saline with increased burial (e.g. Laier 2008; Kharaka & Hanor 2003). \u0000The brine chemistry reported here shows a distinct depth trend, which reflects original connate formation waters that are modified through burial diagenesis. We have classified the brines into brine types, which are shown to be related to their depositional environment, depth, geological formation and geographical domains.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90838754","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}
Pub Date : 2019-07-17DOI: 10.34194/GEUSB-201943-02-06
O. Bennike, J. Jensen, F. N. Sukstorf, M. Rosing
Global population has increased rapidly in recent decades. So far, it has been possible to feed the growing population by using more and more land for agriculture, using irrigation and artificial fertilisers and by improving the efficiency of agriculture. Recently the growth of the global agricultural area has slowed. However, the need for food will continue to grow markedly in coming years. This demand can no longer be met by using increasingly more land for agriculture, and in many areas it is not possible to increase crop production by irrigation (Wise 2013). Large areas in the tropics are characterised by strongly depleted soils with low concentrations of nutrients such as nitrogen, phosphorous and potassium. In such areas, the yield of crop per hectare is much lower than the theoretical yield using optimal fertilising (Ray et al. 2013). Reducing the gap between real and potential crop productivity offers the best solution to achieve food security for the world’s rapidly growing population. Poor soil quality in the tropics is largely due to the rapid weathering of minerals and leaching of dissolved nutrients in the warm and humid climate. If weathered minerals are not replaced by new minerals, for example due to volcanic activity, then soil fertility continues to decline over time. Therefore, it is necessary to use increasing amounts of fertilisers to feed growing populations in the tropics. Most nutrients come from geological deposits; the only exception is nitrogen, which can be extracted from the atmosphere. Nutrients that are mined constitute a limited resource. Hence the known occurrences of phosphorous can only cover the current demand for a few decades (van Vuuren et al. 2010). In recent years, investigations have been conducted to see if the productivity of nutrient-poor soils can be improved by the application of glacial rock flour from Greenland. Rock flour in southern West Greenland consists of fine-grained silt, formed by the grinding of bedrock by stones and boulders embedded in the basal part of glaciers. Preliminary results indicate that plants cultivated in soils with rock flour can achieve increased growth (M.T. Rosing, unpublished data 2019). However, the research is still in its early days and many questions remain. We do not know why adding rock flour to soil results in increased growth. Maybe the silt fraction improves the soil properties. Also we do not know if it is feasible to mine rock flour and transport it to the tropics. As a first step towards answering some of these questions, our aim here was to simply map and sample the glacial rock flour in Tasersuaq, a large proglacial lake in southern West Greenland, c. 105 km north-east of Nuuk.
近几十年来,全球人口增长迅速。到目前为止,通过将越来越多的土地用于农业、使用灌溉和人工施肥以及提高农业效率,养活不断增长的人口已经成为可能。最近,全球农业面积的增长已经放缓。然而,未来几年对粮食的需求将继续显著增长。这种需求不能再通过使用越来越多的土地用于农业来满足,而且在许多地区,通过灌溉来增加作物产量是不可能的(Wise 2013)。热带大片地区的特点是土壤严重枯竭,氮、磷和钾等养分浓度低。在这些地区,每公顷作物的产量远低于使用最佳施肥的理论产量(Ray et al. 2013)。缩小作物实际生产力与潜在生产力之间的差距是实现世界快速增长人口粮食安全的最佳解决方案。热带地区土壤质量差在很大程度上是由于矿物的快速风化和淋溶的溶解营养素在温暖和潮湿的气候。如果风化的矿物质没有被新的矿物质取代,例如由于火山活动,那么土壤肥力会随着时间的推移而继续下降。因此,有必要使用越来越多的肥料来养活热带地区不断增长的人口。大多数营养物质来自地质沉积物;唯一的例外是氮,它可以从大气中提取。被开采出来的营养物质是一种有限的资源。因此,已知的磷储量只能满足当前几十年的需求(van Vuuren et al. 2010)。近年来,人们进行了调查,以了解是否可以通过使用格陵兰岛的冰川岩粉来提高营养贫乏土壤的生产力。西格陵兰岛南部的岩粉由细粒度的泥沙组成,这些泥沙是由嵌入冰川基部的石头和巨石磨碎基岩形成的。初步结果表明,在含有岩粉的土壤中种植的植物可以促进生长(M.T. Rosing, 2019年未发表的数据)。然而,这项研究仍处于早期阶段,还存在许多问题。我们不知道为什么在土壤中加入石粉会促进生长。也许泥沙部分改善了土壤的性质。我们也不知道如果它是可行的,我的石粉和运输到热带地区。作为回答这些问题的第一步,我们的目标是简单地绘制和取样塔瑟瓦克的冰川岩石粉。塔瑟瓦克是西格陵兰岛南部的一个大型前冰川湖,位于努克东北约105公里处。
{"title":"Mapping glacial rock flour deposits in Tasersuaq, southern West Greenland","authors":"O. Bennike, J. Jensen, F. N. Sukstorf, M. Rosing","doi":"10.34194/GEUSB-201943-02-06","DOIUrl":"https://doi.org/10.34194/GEUSB-201943-02-06","url":null,"abstract":"Global population has increased rapidly in recent decades. So far, it has been possible to feed the growing population by using more and more land for agriculture, using irrigation and artificial fertilisers and by improving the efficiency of agriculture. Recently the growth of the global agricultural area has slowed. However, the need for food will continue to grow markedly in coming years. This demand can no longer be met by using increasingly more land for agriculture, and in many areas it is not possible to increase crop production by irrigation (Wise 2013). \u0000Large areas in the tropics are characterised by strongly depleted soils with low concentrations of nutrients such as nitrogen, phosphorous and potassium. In such areas, the yield of crop per hectare is much lower than the theoretical yield using optimal fertilising (Ray et al. 2013). Reducing the gap between real and potential crop productivity offers the best solution to achieve food security for the world’s rapidly growing population. \u0000Poor soil quality in the tropics is largely due to the rapid weathering of minerals and leaching of dissolved nutrients in the warm and humid climate. If weathered minerals are not replaced by new minerals, for example due to volcanic activity, then soil fertility continues to decline over time. Therefore, it is necessary to use increasing amounts of fertilisers to feed growing populations in the tropics. Most nutrients come from geological deposits; the only exception is nitrogen, which can be extracted from the atmosphere. Nutrients that are mined constitute a limited resource. Hence the known occurrences of phosphorous can only cover the current demand for a few decades (van Vuuren et al. 2010). \u0000In recent years, investigations have been conducted to see if the productivity of nutrient-poor soils can be improved by the application of glacial rock flour from Greenland. Rock flour in southern West Greenland consists of fine-grained silt, formed by the grinding of bedrock by stones and boulders embedded in the basal part of glaciers. Preliminary results indicate that plants cultivated in soils with rock flour can achieve increased growth (M.T. Rosing, unpublished data 2019). However, the research is still in its early days and many questions remain. We do not know why adding rock flour to soil results in increased growth. Maybe the silt fraction improves the soil properties. Also we do not know if it is feasible to mine rock flour and transport it to the tropics. As a first step towards answering some of these questions, our aim here was to simply map and sample the glacial rock flour in Tasersuaq, a large proglacial lake in southern West Greenland, c. 105 km north-east of Nuuk.","PeriodicalId":49199,"journal":{"name":"Geological Survey of Denmark and Greenland Bulletin","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87964680","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}