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The Greenland Analogue Project Yearly Report 2010 Working Report 2012-16 The Greenland Analogue Project Yearly Report 2010 Harper J., Hubbard A., Ruskeeniemi T., Claesson Liljedahl L., Lehtinen A., Booth A., Brinkerhoff D., Drake H., Dow C., Doyle S., Engström J., Fitzpatrick A., Frape S., Henkemans E., Humphrey N., Johnson J., Jones G., Joughin I., Klint KE., Kukkonen I., Kulessa B., Landowski C., Lindbäck K., Makahnouk M., Meierbachtol T., Pere T., Pedersen K., Pettersson R., Pimentel S., Quincey D., Tullborg E-L., van As D. April 2012 POSIVA OY FI-27160 OLKILUOTO, FINLAND Tel +358-2-8372 31 Fax +358-2-8372 3709 Working Report 2012-16 The Greenland Analogue Project Yearly Report 2010 Harper J., Brinkerhoff D., Johnson J., Meierbachtol T. University of Montana Hubbard A., Doyle S., Fitzpatrick A., Pimentel S., Quincey D. Aberystwyth University Ruskeeniemi T., Engström J., Kukkonen I. Geological Survey of Finland Claesson Liljedahl L. Svensk Kärnbränslehantering AB Lehtinen A., Pere T. Posiva Oy Booth A., Dow C., Jones G., Kulessa B. Swansea University Drake H. Linnéuniversitetet Frape S., Henkemans E., Makahnouk M. University of Waterloo Humphrey N., Landowski C. University of Wyoming Joughin I. University of Washington Klint KE., van As D. Geological Survey of Denmark and Greenland - GEUS Lindbäck K., Pettersson R. Uppsala University Pedersen K. Micans AB Tullborg E-L. Terralogica April 2012 Base maps: ©National Land Survey, permission 41/MML/12 Working Reports contain information on work in progress or pending completion. ABSTRACT A four-year field and modelling study of the Greenland ice sheet and subsurface conditions, Greenland Analogue Project (GAP), has been initiated collaboratively by SKB, Posiva and NWMO to advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository. The study site encompasses a land terminus portion of the Greenland ice sheet, east of Kangerlussuaq, and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project begins in 2009 and is scheduled for completion in 2012. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with cold climate conditions and glacial cycles, and their impact on the long-term performance of deep geological repositories for spent nuclear fuel, will be significantly improved by studying a modern analogue. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a better understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. This report was produced by the GAP team members and presents an overview of the activities within the GAP during the interval January 1 to December 31, 2010, as well as research results obtained during this time frame. Research for the GAP is ongoing, and additional results related to the data presented here may become available in the future and will be presented in subsequent annual reports. Keywords: Greenland, Kangerlussuaq, glaciology, geology, hydrogeology, nuclear waste management, natural analogue, glacial meltwaters. Grönlannin Analogia Projekti. Vuosiraportti 2010 TIIVISTELMÄ Neljävuotinen kenttä- ja mallinnustyö, Grönlannin Analogia Projekti (GAP) aloitettiin vuonna 2009 Länsi-Grönlannissa, Kangerlussuaqin läheisyydessä. Projekti toteutetaan yhteistyössä Posivan, SKBn ja NWMOn kanssa ja sen tarkoituksena on kehittää ymmärrystä jääkausien vaikutuksista ja niiden merkityksestä geologisen loppusijoituk- sen pitkäaikaisturvallisuuteen. Tutkimuksessa keskitytään erityisesti mannerjään liikkei- siin tutkimusalueella, sulavesien muodostumiseen jään pinnalla ja jäänalaisiin olosuh- teisiin sekä alueen pohjavesien esiintymiseen ja niiden kemialliseen laatuun. Tutkimus- alue havaittiin edustavaksi luonnonanalogia projektille jo esiselvityksien aikana vuonna 2005 ja 2008, jolloin alueella havaittiin olevan useita yhtäläisyyksiä Skandinavian ja Kanadan luonnonolosuhteille. Nykykäsitys hydrologisesta, hydrogeologisesta- sekä geokemiasta prosesseista kylmien ilmastojen alueella, jääkausisykleistä sekä niiden vaikutuksesta geologisen loppusijoi- tuksen pitkäaikaisturvallisuuteen, tulee merkittävästi kehittymään tämän projektin myötä. GAP -projekti tuo ensikäden tietoa mannerjään in situ vaikutuksista kallioperään sekä siinä esiintyviin prosesseihin ja parametreihin. Tätä tietoa käytetään hyväksi paran- tamaan käsitystä mannerjään vaikutuksista geologiseen loppusijoitukseen, parantamaan turvallisuusperustelukäsitystä sekä riskikartoitusta tulevien jääkausien osalta. Tämän raportin ovat kirjoittaneet GAP -projektin jäsenet, ja se pitää sisällään vuonna 2010 tehdyt kenttätyöt sekä alustavat tutkimustulokset. Kenttätyöt jatkuvat vuoteen 2012 saakka. Tulevat työt sekä tulokset käsitellään vuosittaisissa raporteissa. Avainsanat: Grönlanti, Kangerlussuaq, jäätikkö, geologia, hydrogeologia, käytetyn ydinpolttoaineen jätehuolto, luonnonanalogia, jäätikön sulavesi. PREFACE The report has been finished in cooperation with Svensk Kärnbränslehantering AB (SKB) and it has been published in the SKB's technical and social science report series as R-11-23. 1 TABLE OF CONTENTS ABSTRACT TIIVISTELMÄ PREFACE 1 INTRODUCTION ................................................................................................... 3 1.1 Overview of the GAP sub-projects ............................................................. 4 2 SUB-PROJECT A ACTIVITIES 2010 .................................................................... 7 2.1 Introduction and objectives ........................................................................ 7 2.2 Remote sensing ......................................................................................... 9 2.3 Meteorology, climate and surface melt / run off ....................................... 14 2.4 Ice dynamics and kinematic-GPS ............................................................ 20 2.5 Ice radar ................................................................................................... 28 2.6 Active seismics ........................................................................................ 34 2.7 Passive seismics ..................................................................................... 40 2.8 Coupled meltwater production – ice flow modelling ................................. 50 2.9 Summary ................................................................................................. 54 2.10 2011 plans ............................................................................................... 55 3 SUB-PROJECT B ACTIVITIES 2010 .................................................................. 57 3.1 Introduction and objectives ...................................................................... 57 3.2 Activities ................................................................................................... 59 3.2.1 Deep-Ice hot water drill design and fabrication ............................ 59 3.2.2 Radar reconnaissance of drilling sites .......................................... 60 3.2.3 Transport of drill ........................................................................... 61 3.2.4 Sensor design and manufacture .................................................. 61 3.2.5 Field logistics planning ................................................................. 61 3.2.6 2010 summer field campaign ....................................................... 61 3.2.7 2010 fall field campaign................................................................ 61 3.2.8 Modelling activities ....................................................................... 62 3.3 Field equipment and methods.................................................................. 62 3.3.1 Hot water drill ............................................................................... 62 3.3.2 Borehole sensors ......................................................................... 62 3.3.3 GPS surface velocity .................................................................... 64 3.3.4 Ice penetrating radar .................................................................... 65 3.3.5 Water sampling ............................................................................ 65 3.4 Results, 2010 field campaigns ................................................................. 66 3.4.1 Water level impulse experiments ................................................. 67 3.4.2 Basal water pressure.................................................................... 70 3.4.3 Borehole video/photography ........................................................ 71 3.4.4 Ice temperature ............................................................................ 75 3.4.5 Ice penetrating radar measurements of ice depth ....................... 76 3.4.6 GPS surface velocity .................................................................... 76 3.4.7 Basal water and sediment sampling ............................................. 76 3.5 Field campaign preliminary interpretations and conclusions ................... 84 3.6 2011 plans ............................................................................................... 84 4 SUB-PROJECT C ACTIVITIES 2010 .................................................................
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