This file is not intended to be read by humans. Please see the formatted index to item ref. cks140 - Volume 47(2)


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Contents List
The contents list, and downloads of individual papers will be available by Friday 28 August.
 
%2 £6.00 plus postage %J Cave and Karst Science %E John Gunn, David Lowe, Gina Moseley %D 2020 %C Buxton %I British Cave Research Association %P iv + 64 %Z A4, with photos, maps and diagrams %N 47(2),2020 (August),August 2020 %@ ISSN 1356-191X %3 The Transactions of the British Cave Research Association. %3
This is a special thematic issue of Cave and Karst Science, devoted to the expedition report of the Greenland Caves Project 2019. BCRA is grateful for the financial contribution from the Project, which has allowed publication of a larger than normal issue that is also available as Open Access %_ end # ===== ARTICLES SECTION %P i %T Front cover photo %X Gina Moseley and Chris Blakeley admiring large hoar frost crystals, some the size of dinner plates, inside Crystal Kingdom Cave in northeast Greenland. (Photo: Robbie Shone) %A Robbie Shone %Z openAccess %_ end %P ii %T Notes for Contributors %_ end %P 53 %T Contents %_ end %P 54 %T Editorial %A David Lowe, John Gunn, Gina Moseley %Z openAccess %_ end %T History of exploration in northeast Greenland %P 55-59 %A Gina E MOSELEY %X Solution caves in Greenland were first discovered in 1960 at Lat: +80° during Operation Groundhog – a programme to investigate emergency landing sites for aircraft, run by the United States Air Force Cambridge Research Laboratories Ice-Free Land Program and US Geological Survey. Subsequently, the first dedicated caving expedition to northeast Greenland took the form of a four-man land-based team in 1983. The next dedicated caving expeditions to the area were those of the Greenland Caves Project in 2015 and 2019, though there were attempts to locate a new cave region at Lat: +70° in 2018. In this report, the caving expeditions are put into context of the history of exploration in northeast Greenland, from the beginning – with the pre-Inuit people – to the present day. %8 Received: 24 May 2020; Accepted: 06 June 2020 %Z openAccess %9 paper %_ end %T The geology of the Centrumsø area of Kronprins Christian Land, northeast Greenland, and lithological constraints on speleogenesis %P 60-65 %A M Paul SMITH, Jan Audun RASMUSSEN %X The cave-bearing limestones of Kronprins Christian Land, northeast Greenland, were deposited on the Laurentian craton, on a sector of the margin referred to the Franklinian Basin. A 1.4km succession of Ordovician–Silurian carbonates rests unconformably on Lower Cambrian sandstones and Neoproterozoic sediments, and the carbonate succession is overlain conformably by late Llandovery (Silurian) turbidites that mark the collapse of the continental shelf at the onset of Caledonian tectonics, due to loading by thrust sheets and their erosional products. The cave-bearing limestones form a thin-skinned duplex that sits beneath the Vandredalen thrust sheet, which in turn lies in the footwall of a major fault that bounds exhumed, deep crustal rocks. Despite the thickness of the Lower Palaeozoic succession, most of the caves are concentrated in a thin interval comprising the subtidal–peritidal carbonates of the Odins Fjord Formation and the overlying reef limestones of the Samuelsen Høj Formation (both late Llandovery, Silurian). Caves are found only in the vicinity of the Samuelsen Høj reefs despite extensive exploration of the area as part of the regional mapping programme and the Greenland Caves Project, suggesting a possible genetic link even for those caves developed entirely within the Odins Fjord Formation. %K Franklinian Basin; Caledonian Orogeny; Silurian; North-East Greenland National Park %8 Received: 02 June 2020; Accepted: 13 June 2020. %Z openAccess %9 paper %_ end %T Investigations to constrain retreat of the Greenland Ice Sheet: glacial geomorphology and sampling for cosmogenic exposure dating of the Centrumsø area, Kronprins Christian Land, northeast Greenland %P 66-73 %A Andrew J SOLE, Ádam IGNÉCZI, M Paul SMITH, Chris D CLARK %X Over the last few decades atmospheric warming across the Arctic has been far more rapid than elsewhere in the world, contributing to an increase in the sea-level contribution from the Greenland Ice Sheet. Given predictions of continuing atmospheric warming during the 21st century and beyond, it is crucial to understand how the ice sheet has responded to past variations in climate. Kronprins Christian Land lies in a climatically sensitive, yet sparsely studied part of northeast Greenland, in an inter-ice-stream region just north of Nioghalvfjerdsbrae. This paper presents the results of preliminary geomorphological mapping from a 2m spatial-resolution digital elevation model of a 5500km2; region around Centrumsø, as well as a report of sampling for cosmogenic exposure dating, and field observations concerning the extent and nature of palaeo-ice coverage and dynamics. Twenty-one 2kg samples were collected from carefully selected glacial erratics of various lithologies using a hammer and chisel as well as a small angle-grinder. %X In general, moraine ridges in the study area are relatively small (2–5m in height) and lack a prominent peak, reflecting limited sediment availability, and suggesting some post-glacial re-mobilization of sediment or deflation caused by melting of the moraines' ice cores. Striated cobbles and boulder-sized clasts were observed at up to 540m a.s.l., sub-rounded erratics (some of which were sampled) at up to 800m a.s.l. and streamlined bedrock at up to 360m a.s.l., all of which indicate sliding between the ice and the bedrock and temperate basal conditions. In addition, several proglacial spillways were noted, along with numerous terraces, commonly situated between lateral moraines and valley sides, which are probably kame terraces formed by glaciofluvial transport and deposition. The prevalence of these landforms indicates significant glaciofluvial action requiring large volumes of meltwater, suggesting this region experienced high-volume melt in short intensive summers during past ice-recession events. %K Greenland Ice Sheet; glacial geomorphology; climate change; cosmogenic exposure dating; Kronprins Christian Land; Northeast Greenland National Park %8 Received: 24 May 2020; Accepted: 23 June 2020 %Z openAccess %9 paper %_ end %T Cave discoveries and speleogenetic features in northeast Greenland %P 74-87 %A Gina E MOSELEY, Hazel A BARTON, Christoph SPÖTL, Paul TÖCHTERLE, M Paul SMITH, Stig Erick BJERKENÅS, Christopher BLAKELEY, Peter D HODKINSON, Robert C SHONE, Hans Christian SIVERTSEN, Mark WRIGHT %X Solution caves situated in the Centrumsø region of northeast Greenland (80°N) were first documented in 1960. Since then, there have been three dedicated caving expeditions to the area that have increased the numbers of cave observations and discoveries substantially. Here, the larger caves, as documented by the Greenland Caves Project during 2015 and 2019, are presented, including surveys and summaries of their key features. Additionally, smaller caves and potential leads, as documented during 2019, are also presented. %8 Received: 03 July 2020; Accepted: 07 July 2020 %Z openAccess %9 paper %_ end %T Microbiological observations in the caves of Grottedal, Kronprins Christian Land, northeast Greenland %P 88-92 %A Hazel A BARTON, George J BRELEY, M Paul SMITH %X The caves of Grottedal, Kronprins Christian Land, northeast Greenland were examined for microbial activity during the 2019 Northeast Greenland Caves Project. Given the freezing temperatures, desiccating conditions, and poor organic content of these caves, little microbial activity was expected. Nonetheless, field observation demonstrated a surprising level of microbial activity, dominated by photosynthetic species in near-entrance zones. This included the presence of extremophilic green algae (chlorophytes), along with cyanobacteria that formed photokarren. Other microbial activity that was observed indirectly included microbialites and iron-oxide deposits, which might indicate microbial contributions to speleogenesis when the region was warmer and cave development was ongoing. The Grottedal area and caves have several environmental features in common with Mars: a polar desert under desiccating, low-light conditions. Nonetheless, observations at Grottedal indicate that significant microbial activity, which can generate long-term geochemical and geomorphological signatures, is possible. Such data suggest that the Grottedal caves could provide an important testbed for future astrobiological investigations and instrument development. %K Grottedal caves; microbialites; microbial iron-oxidation; low temperature photosynthesis; photokarren; Northeast Greenland National Park %8 Received: 25 April 2020; Accepted: 27 May 2020 %Z openAccess %9 paper %_ end %T Cryogenic features of the permafrost ice caves of Grottedal, northeast Greenland %P 93-99 %A Hazel A BARTON, George J BRELEY, Paul TÖCHTERLE, Gina E MOSELEY %X The caves of Grottedal, Kronprins Christian Land, northeast Greenland, are found within the continuous Arctic permafrost zone. The caves contain several cryogenic features, including minerals and ice deposits. Convection loops within the air of the caves appear to create a sublimation horizon, above which increasing humidity leads to hoar frost formation. Below this sublimation horizon, dry and desiccating conditions lead to the leaching of CaCO3 and the formation of magnesian calcite and kutnohorite. Evidence of condensation corrosion in these caves may also be responsible for the formation of a new type of cryogenic speleothem (called cryogenic frostwork), which may form from freezing of this condensate on surfaces. Cave-air dynamics, driven by the cold temperatures (measured as low as -17.1°C) and climatic conditions of these permafrost caves, are considered to be responsible for the formation of these observed cryogenic features. %K Grottedal caves; permafrost; hoar frost; kutnohorite; cryogenic frostwork %8 Received: 25 April 2020; Accepted: 26 May 2020. %Z openAccess %9 paper %_ end %T Characterization of northeast Greenland cave sediments %P 100-103 %A Johannes TISCHLER, Paul TÖCHTERLE and Gina E MOSELEY %X Clastic sediments deposited in caves are useful archives of past hydrological and environmental conditions. Here we report the results of investigations into three samples of clastic sediments collected from caves in northeast Greenland. The samples have a mineralogical composition dominated by calcite, dolomite and quartz. Two of the samples are homogenous silts, whereas the third sample is laminated with couplets that begin with a pale grey silt, and fine upwards to a darker clayey-silt that is higher in organic carbon. All sediments were deposited in calm to stagnant conditions though the laminae in the one sample indicate pulsing in the depositional process, possibly caused by waxing and waning of an internal ice plug or external glacier. %8 Received: 25 April 2020; Accepted: 09 May 2020 %Z openAccess %9 paper %_ end %T Basic meteorological observations in the Centrumsø region of northeast Greenland %P 104-106 %A Anika DONNER, Paul TÖCHTERLE, Gina E MOSELEY %X In recent years, northeast Greenland has increasingly become a centre for palaeoclimate research; however, placing palaeoclimate observations in the context of present climatology has been hampered by the limited number of meteorological stations that exist in this remote region. During the 2015 and 2019 Greenland Caves Project expeditions in the Centrumsø/Grottedal region (Lat: +80°), basic spot measurements were taken to obtain observational knowledge about the meteorology of the area. The results show an air temperature range between 6.1°C and 18.9°C and low wind speeds up to 4m s–1. These observations are generally in agreement with previous studies, suggesting a more continental climate in the ice-free Centrumsø/Grottedal region as compared to measurements from meteorological stations on the Greenland ice sheet (part of the PROMICE project) and on the coast (Station Nord, Danmarkshavn). Reliable meteorological measurements operating over longer timescales would be helpful for palaeoclimate studies being conducted in the Centrumsø/Grottedal region. %8 Received: 24 May 2020; Accepted: 19 June 2020. %Z openAccess %9 paper %_ end %T Greenland Caves Project 2019 Expedition Report. Appendices %P 107-116 %X Appendix 1: Permission and Permitting Process (Gina E MOSELEY) %X Appendix 2: Logistics and Transport (Gina E MOSELEY) %X Appendix 3: Medical Report (Peter D HODKINSON) %X Appendix 4: Equipment (Gina E MOSELEY) %X Appendix 5: Rigging, Safe Access and Safety (Chris BLAKELEY) %X Appendix 6: Photography, Filming and Power (Robbie SHONE) %X Appendix 7: Structure-from-Motion Photogrammetry (Paul TÖCHTERLE) %X Appendix 8: Investigations of the entomologyof the Centrumsø area,Kronprins Christian Land, northeast Greenland (M Paul SMITH) %X Appendix 9: Remote Expedition Research Collaboration (Nathan SMITH) %X Appendix 10: Expedition Budget and Sponsors (Gina E MOSELEY) %Z openAccess %9 paper %_ end %P iii %T Research Fund and Grants %_ end %P iv %T Back cover photos %X A selection of images from the Centrumsø area of Kronprins Christian Land, northeast Greenland. See contents page for photo captions %A Robbie Shone, Paul Smith, Andrew Sole %Z openAccess %_ end