Alfred-Wegener-Institut für Polar- und Meeresforschung Forschungsstelle Potsdam Arbeitsgruppe „Periglazialforschung“ Permafrost landform studies on Earth: Implications for periglacial landscape evolution and habitability on Mars Dissertation zur Erlangung des akademischen Grades "doctor rerum naturalium" (Dr. rer. nat.) in der Wissenschaftsdisziplin „Terrestrische Geowissenschaften“ als kumulative Arbeit eingereicht an der Mathematisch-Naturwissenschaftlichen Fakultät der Universität Potsdam von Mathias Ulrich Potsdam, 6. Juli 2011 “Given a phenomenon, A, whose antecedent we seek. First we ransack the memory for some different phenomenon, B, which has one or more features in common with A, and whose antecedent we know. Then we pass by analogy from the ancedent of B, to the hypothetical antecedent of A, solving the analogic proportion – as B is to A, so is the ancedent of B to the ancedent of A.” Grove Karl Gilbert, 1886. The inculcation of scientific method by example. Am. Jour. Sci. 3d(31), 284-299. "There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. - There is another theory which states that this has already happened." Douglas Adams, 1980. The Restaurant at the End of the Universe. Pan Book Ltd., London. Table of contents _______________________________________________________________________________ Table of contents Table of contents ................................................................................................................................. i Abstract ............................................................................................................................................. iv Kurzfassung ....................................................................................................................................... vi 1. Introduction ................................................................................................................................ 1 Preface .......................................................................................................................................... 1 1.1 Scientific background ......................................................................................................... 1 1.1.1 Permafrost, ground ice, and periglacial features on Earth and Mars ....................... 1 1.1.2 The Martian mid-latitude landscapes and Utopia Planitia ....................................... 3 1.1.3 Terrestrial periglacial landscapes as Martian environmental analogues: Introduction to the study sites in Siberia and on Svalbard ...................................... 6 1.1.4 Climatic and astrobiological relevance of potential Martian periglacial landscapes ................................................................................................................ 7 1.2 Aims and approaches .......................................................................................................... 9 1.3 Thesis organization ........................................................................................................... 10 1.3.1 Overview of chapters ............................................................................................. 10 1.3.2 Authors´ contribution ............................................................................................ 11 2. Thermokarst in Siberian ice-rich permafrost: Comparison to asymmetric scalloped depressions on Mars................................................................................................................. 13 Abstract ...................................................................................................................................... 13 2.1 Introduction and background ............................................................................................ 14 2.2 Regional setting ................................................................................................................ 16 2.2.1 Earth ...................................................................................................................... 16 2.2.2 Mars ....................................................................................................................... 18 2.3 Data and Methods ............................................................................................................. 20 2.3.1 Terrestrial data ....................................................................................................... 20 2.3.1.1 Field data ................................................................................................. 20 2.3.1.2 GIS and remote-sensing analyses ............................................................ 21 2.3.2 Martian data ........................................................................................................... 22 2.4 Results............................................................................................................................... 23 2.4.1 Terrestrial thermokarst depression morphometry, geomorphology, and surface features ...................................................................................................... 23 2.4.2 Insolation and thermal properties of terrestrial thermokarst depression................ 28 2.4.3 Morphological properties of scalloped depressions on Mars ................................ 31 2.4.4 Insolation and thermal properties of scalloped depressions within the Martian mantle terrain ......................................................................................................... 34 i Table of contents _______________________________________________________________________________ 2.5 Discussion ......................................................................................................................... 37 2.5.1 Terrestrial characteristics of slope asymmetry and spatially-directed thermokarst development ...................................................................................... 37 2.5.2 Implications for scalloped depression development on Mars ................................ 40 2.6 Conclusions ....................................................................................................................... 44 Acknowledgements .................................................................................................................... 45 3. Polygon pattern geomorphometry on Svalbard (Norway) and western Utopia Planitia (Mars) using high-resolution stereo remote-sensing data ...................................... 46 Abstract ...................................................................................................................................... 46 3.1 Introduction and background ............................................................................................ 47 3.2 Characterization of study areas ......................................................................................... 50 3.2.1 Svalbard (Adventdalen) ......................................................................................... 50 3.2.2 Mars (Utopia Planitia, UP) .................................................................................... 51 3.3 Methods and data .............................................................................................................. 53 3.3.1 Field work and laboratory analyses ....................................................................... 53 3.3.2 Remote sensing data .............................................................................................. 53 3.3.3 GIS analysis and polygon mapping ....................................................................... 54 3.3.4 Numerical analyses ................................................................................................ 55 3.4 Results............................................................................................................................... 57 3.4.1 Geomorphology and morphometry of Adventdalen polygons .............................. 57 3.4.2 Sedimentology of the Adventdalen polygons ........................................................ 62 3.4.3 Geomorphology and morphometry of Utopia Planitia (UP) polygons .................. 64 3.4.4 Results of the multivariate statistics ...................................................................... 69 3.5 Discussion ......................................................................................................................... 71 3.5.1 Relationship between geomorphometry and genesis for the terrestrial polygons ................................................................................................................ 71 3.5.2 Comparability of terrestrial and Martian polygonal structures .............................. 75 3.5.3 Genesis of Mars polygons and environmental implications .................................. 79 3.6 Conclusions ....................................................................................................................... 83 Acknowledgements .................................................................................................................... 84 4. Habitable periglacial landscapes in Martian mid-latitudes ................................................. 85 Abstract .....................................................................................................................................