Jeffrey Kargel

ABSTRACT Since the Galileo NIMS sensor obtained the spectral data of the surface of Europa, several laboratory studies have been performed to ascertain the composition of the dark terrains. Some hydrated salts and acids have been proposed to explain the spectral signatures of these areas, but no single mineral fit is completely suitable. Until now, a flash frozen aqueous mixture of magnesium and sodium sulfate with sulphuric acid is the better match. The structural relationship of these materials to the geological features (such as fractures) and geochemical models of chondrite alteration indicate that they are originally endogenic. However, as some authors have already proposed, the high radiation environment has to modify these substances. The cryogenesis of the observed mineralogy may provide some clues about the compositional characteristics of the potential global water ocean of Europa, if this ocean constitutes the source. The crystallization path of the original cryomagmas will determine the final paragenesis observed on the surface. Fractional crystallization of the briny magmas may produce mineral differentiation, resulting in an enrichment of the acidic components as the temperature decreases due to the lower melting point of these materials. But if the solidification occurs as flash freezing, neutral to acidic mineral assemblages are possible. In this case, the original composition would be of Mg-Na sulphates-rich, and the acidic character would occur mainly by radiolysis. A sulphuric acid component should be a secondary product from the alteration of the sulfate paragenesis produced by radiolysis at low temperature, although endogenic acid brines should not be totally rejected. Terrestrial analogs to these chemistries are useful to constrain the habitability of the ocean environment and supply natural brines for new experiments. Several crystallization experiments have been done with brines from Tirez lake (central Spain), and the results show different final mineral assemblages and spectra depending on the P-T pathways used.

... GRS constraints on the character of possible ancient oceans on Mars: consistencies with Earth analogues ... 4) Space Science and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, United States, (5) West Coast and Alaska Tsunami Warning Center ...

In this talk, we will discuss objectives and preliminary results for a research effort that uses a combined experimental and theoretical approach to: 1) determine fundamental physical properties of icy moon materials (ices and candidate cryomagmas) at small scales through cryogenic laboratory experiments; and 2) through modeling, extend these experimental results to explain observations at planetary length scales. These data

We present new facilities that offer the capability to experimentally determine the thermophysical, rheological, mechanical, and chemical properties of icy materials at cryogenic temperatures that are applicable to outer solar system objects.

Changes in glaciers and ice caps provide some of the clearest evidence of climate change and have impacts on global sea level fluctuations, regional hydrological cycles and local natural hazard situations. Internationally coordinated collection and distribution of standardized information about glaciers and ice caps was initiated in 1894 and is today coordinated within the Global Terrestrial Network for Glaciers (GTN-G).

Jupiter's satellite Io is the most geologically dynamic solid body in the Solar System. Io undergoes severe tidal heating, induced by the orbital eccentricity forced by Jupiter and the 4:2:1 Laplace resonance between Io, Europa, and Ganymede. Io's high global heat flow (>2 W m-2, compared to the 0.06 W m-2 average for Earth) presages an extremely rich array of

ABSTRACT Global Land Ice Measurements from Space (GLIMS) is an international initia- tive to map the world’s glaciers and to build a geospatial database of glacier vector outlines that is usable via the World Wide Web. The GLIMS initiative includes glaciologists at 82 institutions, organized into 27 Regional Centers (RCs), who analyze satellite imagery to map glaciers in their regions of expertise. The results are collected at the U.S. National Snow and Ice Data Center (NSIDC) and ingested into the GLIMS Glacier Database. A concern for users of the database is data quality. The process of classifying multispectral satellite data to extract vector outlines of glaciers has been automated to some degree, but there remain stages requiring human interpretation. To quantify the repeatability and precision of data provided by different RCs, we designed a method of comparative image analysis whereby analysts at the RCs and NSIDC derived glacier outlines from the same set of images, chosen to contain a variety of glacier types. We carried out four such experiments. The results were compiled, compared, and analyzed to quantify inter-RC analysis consistency. These compar- isons have improved RCs’ ability to produce consistent data, and in addition show that in the lower reaches of a glacier, precision of glacier outlines is typically 3 to 4 pixels. Variability in the accumulation area and over parts of the glacier that are debris-covered tends to be higher. The ingest process includes quality control steps that must be passed before data are accepted into the database. These steps ensure that ingested data are well georeferenced and internally consistent. The GLACE experiments and ingest-time quality control steps have led to improved quality and consistency of GLIMS data. This chapter presents the GLACE experiments and the quality control steps incorporated into the data ingest process. More recent similar studies are referenced.

Experiments with different sulfates using conditions of the martian surface (T, P, radiation, atmospheric composition) have been performed to constrain the stability of the hydrated phases and detect any modification from their standard spectra.

Page 1. Automated Global Feature Analyzer - A Driver for Tier-Scalable Reconnaissance Wolfgang Fink('), Ankur Datta 2), James M. Dohm(3' 4), Mark A. Tarbell('), Farrah M. Jobling(5), Roberto Furfaro(6), Jeffrey S. Kargel(3), Dirk Schulze-Makuch(7), Victor R. Baker(3' 4) ...

Title: Spectral Diversity of Terrestrial Banded Iron Formations and Associated Rocks: Implications for Mars Remote Sensing. Authors: Crowley, JK; Hook, SJ; de Souza Filho, CR; de Pereira Silva, G.; Bridges, NT; Thomson, BJ; Kargel, JS; Brown, AJ; Ribeiro da Luz, B.; Baldwin, A ...

... Michel.Mayor@obs.unige.ch Dr. Christopher P. McKay NASA Ames Research Center Moffet Field, CA 94035, USA Prof. Dr. H. Stan-Lotter Institut für Genetik und Allgemeine Biologie Universität Salzburg Hellbrunnerstr. 34 5020 Salzburg, Austria Page 4. Giles M. Marion · Jeffrey ...

The early histories of Earth and Mars included some parallelism of aqueous environments. Oxides and carbonates from the Wittenoom formation (Western Australia) mark a revolution in Earth environmental history started but not completed by Mars.

ABSTRACT Satellite-based remote sensing is critical for monitoring highly dynamic environments that include rapidly changing alpine glaciers, melt-water production, and a variety of natural hazards. Multi-spectral and multi- temporal satellite data in conjunction with digital elevation models can be utilized to assess supraglacial and proglacial lakes, valley impoundment water volumes, and the potential for flood and debris-flow hazards. Advanced remote sensing and GIS-based methodologies represent the only effective approach for periodic assessment and detection of glacier hazards using spatio-temporal data and analysis. Such approaches, however, do not address all of the requirements needed for the development of hazard/disaster warning systems and the generation of unique information to help establish mitigation strategies. Consequently, our objectives are to introduce the methods of fuzzy logic as an additional level of analysis and interpretation to demonstrate how intelligent, knowledge-driven algorithms can be used to assess glacier dynamics and glacier-induced hazards. Operational monitoring of dynamic environments and natural hazards will require multiple levels of analysis and information production using on-board automation. These systems must autonomously assess the hazard potential related to surface processes and the topography, while being able to identify disaster conditions. Such systems should (1) include analytical capabilities to permit automated and comprehensive identification, characterization, and quantification of terrain features (e.g., via Automated Global Feature Analyzer "AGFA"); (2) permit operational multi-scale hazard potential assessment (e.g., automatic global, regional and local assessment capabilities); and (3) permit data integration that fuses existing data and real-time data acquisition into a spatio-temporal framework that facilitates intelligent assessment and monitoring. The fuzzy logic framework may be an ideal approach that serves to represent the intelligent analysis requirement of an operation system because application domain knowledge can be represented in linguistic and numeric form, and can be easily incorporated into a conceptual and numerical model. Such fuzzy systems recently have been proposed as the basis for intelligent, autonomous, science- driven planetary reconnaissance, including systems specifically designed to assess the potential for habitability on Mars and Titan. Here we demonstrate the utility of remote sensing, GIS and fuzzy systems for operational assessment of glacier dynamics and glacier-induced hazards, with an emphasis on design and implementation examples.

ABSTRACT High spatial and spectral resolution electromagnetic imaging data from orbit is now routinely used within a variety of earth science disciplines, including geomorphology, to assess the effects and state of dynamic earth surface processes, as well as for basic geological and geographical mapping. Temporal sampling ranges from very frequent (e.g., multiple times per week for MODIS) at coarse spatial scales (e.g., 250m to 1km/pixel) to relatively infrequent (e.g., a few times per year for ASTER, or worse considering cloud cover constraints) at geomorphically very useful spatial scales (e.g.,

Salts in Melas Chasma should produce large positive thermal anomalies and warm hypersaline conditions at shallow depths. Dewatering may yield brine eruptions, and we argue that in Melas Chasma valley networks were produced this way, not by rainfall.

We use optical images of high-pressure phases of the MgSO4-H2O system, coupled with measurements of pressure, temperature, and volume changes, to report eutectic transitions for pressures up to 200 MPa, with implications for modeling Europa's ocean.

ABSTRACT Glaciers and ice sheets are among the largest unstable parts of the solid Earth. Generally, glaciers are devoid of resources (other than water), are dangerous, are unstable and no infrastructure is normally built directly on their surfaces. Areas down valley from large alpine glaciers are also commonly unstable due to landslide potential of moraines, debris flows, snow avalanches, outburst floods from glacier lakes, and other dynamical alpine processes; yet there exists much development and human occupation of some disaster-prone areas. Satellite remote sensing can be extremely effective in providing cost-effective and time- critical information. Space-based imagery can be used to monitor glacier outlines and their lakes, including processes such as iceberg calving and debris accumulation, as well as changing thicknesses and flow speeds. Such images can also be used to make preliminary identifications of specific hazardous spots and allows preliminary assessment of possible modes of future disaster occurrence. Autonomous assessment of glacier conditions and their potential for hazards would present a major advance and permit systematized analysis of more data than humans can assess. This technical leap will require the design and implementation of Artificial Intelligence (AI) algorithms specifically designed to mimic glacier experts' reasoning. Here, we introduce the theory of Fuzzy Cognitive Maps (FCM) as an AI tool for predicting and assessing natural hazards in alpine glacier environments. FCM techniques are employed to represent expert knowledge of glaciers physical processes. A cognitive model embedded in a fuzzy logic framework is constructed via the synergistic interaction between glaciologists and AI experts. To verify the effectiveness of the proposed AI methodology as applied to predicting hazards in glacier environments, we designed and implemented a FCM that addresses the challenging problem of autonomously assessing the Glacier Lake Outburst Flow Potential and Impound Water Upstream Flow Potential. The FCM is constructed using what is currently our understanding of how glacier lake outbursts occur, whereas the causal connection between concepts is defined to capture the expertise of glacier scientists. The proposed graph contains 27 nodes and a network of connections that represent the causal link between concepts. To test the developed FCM, we defined three scenarios representing glacier lake environmental conditions that either occurred or that are likely to occur in such highly dynamic environments. For each case, the FCM has been initialized using observables extracted from hypothesized remote sensing imagery. The map, which converges to a fixed point for all of the test scenarios within 15 iterations, shows reasoning consistent with that of glacier experts. The FCM-based cognitive approach has the potential to be the AI core of real-time operational hazards assessment and detection systems.

The landscape of the Argyre Planitia and adjoining Charitum and Nereidum Montes in the Martian southern hemisphere has been heavily modified since its formation. Major landforms in Argyre have previously been interpreted as glacial in origin. We re-examine morphologies in this region using MOLA topographic datasets and new details revealed in HiRISE images and discuss the implications for glacial processes.

ABSTRACT On January 4, 2010, a landslide blocked the Hunza River at Attabad, northern Pakistan (36.308°N, 74.820°E). The landslide destroyed the village of Attabad killing 19 people, and formed a dam approximately 1200m long, 350 meters wide, and 125 meters high. The flow of the Hunza river was blocked for 144 days, forming Lake Gojal. In addition to inundating several villages and submerging 22 km of the regionally critical Karakoram Highway, >25,000 people have been displaced or remain cut off from overland connection with the rest of the country. Lake overtopping began on May 29 via a 15m deep spillway excavated through the saddle of the dam. Remarkably, the slowly eroding natural structure remains largely intact and currently represents a new geologic feature, although a threat remains from possible catastrophic outburst flooding. We have monitored growth of the lake with multi-temporal satellite imagery collected from ASTER (Advanced Spaceborne Thermal and Reflection Radiometer) and ALI (Advanced Land Imager) sensors. We applied NASA’s ASTER Global Digital Elevation Model (GDEM) and SRTM-3 digital terrain data, along with field data obtained onsite by Schneider, and by Pakistan’s NDMA to derive volumes of the growing lake. Lake size peaked during mid-summer when it was ~22 km long, 12 km2, 119m deep, and contained 540 to 620 Mm3 water (SRTM-3 and GDEM +5m global correction estimates respectively). Our estimates indicated lake volumes three to four times higher than media quotes, and before spillover, were used to improve predictions of possible flood discharge and disaster management planning. Estimates of valley inflow based on a 31-year hydrographic history (Archer, D., 2003, Jour. Hydrology 274, 198-210) are consistent with our volume infilling estimates. As early as April 14 our volume assessments, coupled with hydrographic and seepage data were used to project a spillover date range of May 28-June 2, bracketing the actual overflow date. Additionally, we have applied vegetation indices (NDVI), landcover classifications, and image differencing change detection techniques to obtain reconnaissance level characterizations of lake-flood affected areas, including flooding of agricultural lands. Our successful prediction of lake growth and initial estimates of affected lands highlights the effectiveness of GIS methods applied to modern satellite datasets, and indicates the importance of monitoring natural hazard events with remote sensing, which can provide rapid assessments and augment onsite observations for disaster management support.

We use optical images of high-pressure phases of the MgSO4-H2O system, coupled with measurements of pressure, temperature, and volume changes, to report eutectic transitions for pressures up to 200 MPa, with implications for modeling Europa's ocean.

ABSTRACT Global trends of glacier response in many mountain environments suggest extensive backwasting and downwasting patterns, with some recent acceleration in the last few decades. Glaciers in the Western Himalaya are perhaps more complicated than other regions due to their complex topography, extensive supraglacial debris cover, and climate system coupling involving the winter westerlies, Indian summer monsoon and possibly the East Asian monsoon. Consequently, we investigated glacier retreat/advance pattern of ten major glaciers in and around the Nanga Parbat massif. Specifically, we used high-quality topographic maps, and Keyhole, SPOT, Landsat and ASTER satellite imageries from 1934-2010. Our results indicate no uniform response of these glaciers to climate change. Some glaciers are retreating and/or maintaining their frontal position whereas others have advanced at different time periods. Average retreat rates, however, are not nearly as large as those reported in the nearby region, and average advance rates are not surge-type. Glacier advances in this region have neither been reported as surge-type glaciers in the past, nor have shown surge-type patterns; therefore, these advances may be due to positive mass balance, or could be an indication of major dynamical change in future. Overall, results indicate that Nanga Parbat glaciers are oscillating and may be responding differently to the current climatic conditions than in the eastern Himalaya (east of the study area), or the Wakhan Pamir/Hindu Kush (northwest of the study area), or Tien Shan region (north of the study area).