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Cambridge University Press 978-0-521-86852-5 - Megaflooding on Earth and Mars Edited by Devon M. Burr, Paul A. Carling and Victor R. Baker Index More information Index abrasion 16 porosity 292 facies 249–258, 259, 260 accommodation space 41, 256, 262 temperature 292, 295 giant bars 38–40, 243, 244 adiabatic cooling 203 thermal conductivitiy 292 Katun valley bars 261 ages thermal gradient 292 Kezek-Jala bar 249, 251 channel ages 195–196 Aram Chaos 178, 179, 211, 291 Komdodj bar 247, 249, 251 exposure age 195 Ares Vallis 173, 174, 178–179, 211–213, Kuray Flood bars 147 formation age 195 216, 218, 221, 297 Inja bar 249, 254 age-dating (see also marine isotope Argyre basin 214, 215, 216, 218 Little Jaloman bar 248, 249–251, stages) 194–196 Argyre Planitia 174, 178, 179 254–256, 261 carbon-14 249 Armero, Columbia 131 Log Korkobi bar 249, 254 cosmogenic dating Aromatum Chaos 184, 291, 301 medial bars crater counting 195, 196, 198 Arsia Mons 267 Missoula bars 147, 261, 262 epoch boundaries Ascraeus Mons 194 morphology 247–248 isochrons 195 Asia 245 pendant bars 39 luminescence dating 249 association 36, 38 primary bars 262 secondaries 195 Athabasca Valles 36, 39, 42, 43, 44, 45, push bars 40 sediments 249 195, 198, 199, 201, 203, 205, 211, secondary bars 267 size-frequency distribution 194 293, 300, 305 sedimentary characteristics 248–258 Aktash 246, 249 age 196 streamlined bars (see bedforms, Alaska 227 discharge 204 streamlined) Allegheny Plateau morphology 199–201 basaltic ring structures 200 Allegheny Vallis 187–188 tectonism 200 bedding alluvial deposits, alluvial fans 209, 210, volcanism 200 cross-bedding 251, 254, 255, 256, 257 218, 220, 245 Auqukuh Vallis 220 plane-bedding 251, 255, 257, 258 alluvial architecture 227 avalanches bedforms 305 Alps, Europe 133 debris 131 antidunes 13, 19–20, 21–22, 40–44, Al-Qahira Vallis 220 rock 129, 277 230, 231, 300 Altai Mountains, Siberia 14, 23, 38, 43, butte-and-basin scabland 71 44, 243, 245, 262, 300 backwater (see also ponding) 281, 283, depositional forms 70–71, 73–74, Amazonian Epoch 194, 195, 204, 205, 285 145–147, 287 294 Baetis Chaos 183, 287 dunes 6, 8, 21, 22, 33, 36, 38, 40, 43, Amazonis Planitia 196, 198, 199 Basin and Range Province, North 44–45, 65, 73–75, 200, 229, 236, American Cordillera 130 America 134, 136 243, 247, 248, 256, 299, 300 American Falls Lake 150, 155 basins (see also lakes) erosional 15–16, 68–70, 71–73, 78, 80, anastomosis (see also morphology,plan Lake Superior basin 118 86, 89, 97, 114, 145–147, 285, 286, view) 14, 66–67, 68, 107, 110, Mediterranean basin 136 287, 304 115, 120 Millican basin, Oregon, USA 134 flutes 17, 84, 88 Aniakchak River 136 moraine basins 132–134, 144 furrows 16, 17–19, 20 Aniakchak Volcano, Alaska 136, 298 natural basins 128 irregularities 300 Antarctica 44 Pasco basin 145 lemniscate forms 70 antidunes (see bedforms) tectonic basins 134–136, 140, 141, 142 loess hills (see also streamlined Apollo seismic network (see seismic volcanic basins 140, 141, 142 forms) 71 networks) bars 33, 36, 38–40, 70–71, 80, 108, 114, longitudinal s-forms 84, 85 AQUARIVER model (see modelling) 116, 117, 120, 229, 230, 232, 244, longitudinal forms 17, 19, 26, 44, 45, aquifers 201, 202, 204, 205, 267, 291, 306 251, 286 71, 107, 110, 111, 196, 214 confined (Mars) 291 architecture 249–258 macroforms 33, 68–71, 95–96, convection in 292, 294 Bonneville Flood bars 146 229–230 flow rates 301 Chuja valley bars 261 megaforms 96–97 perched aquifers 197 eddy bars 39 mesoforms 33, 71–74, 85–95, 114 permeability/-ies 292, 301 expansion bars 38, 39, 230 microforms 33, 80–85 312 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-86852-5 - Megaflooding on Earth and Mars Edited by Devon M. Burr, Paul A. Carling and Victor R. Baker Index More information Index 313 non-directional forms 84 Cerberus plains 195, 198, 199, 200, 201, circum-Chryse channels (see channels) obstacle marks 22–23, 230, 231, 236 204 Claritas Fossae 203 potholes 14, 16–17, 19, 26, 72, 84–85, Chagun–Uzun River 244 clasts (see also interclasts, rip-up clasts) 107, 119 Chakachatna River, Alaska 132 shape 277 scallops 16 Champlain/Hudson sub-lobe 120 Clearwater Lower Athabasca spillway scour 73, 107, 108, 110, 116, 117, 121, Channeled Scabland 1, 2, 3, 13–14, 17, climate change 134, 136, 138 195, 196, 248, 304 19, 22, 23, 38, 39, 65–74, 107, 108, clinoforms 249, 251 streamlined forms 14, 20, 22, 26, 39, 176, 177, 218 clinostratification 251 69–70, 78, 85–86, 95, 107, 108, channels CO2 (see carbon dioxide) 110, 114, 115, 116, 117, 196, 198, boulder dominated beds 296 cobble pods 254, 257, 259 199, 200, 299 circum-Chryse channels 194 collapse 201, 214, 301 transverse forms 22, 40–44, 85, 107, depths 196, 198, 199, 200, 290, 295, Collier Glacier, Oregon, USA 144 110, 111, 300 297, 298 Colorado River 14, 132, 134 transverse s-forms 84 flood 34 Columbia Plateau 66, 67 trenched-spur buttes 68 geometry 291 Columbia River Gorge 65, 74, 145 undulating features 178–179 gravel-dominated beds 296 Columbia Valles 175–177 bedload transport 248 inner channels 17, 19, 107, 110, 111, composite forms 80 Bhutan 133 117, 119, 121, 220, 286 concave features 80 Big Ilgumen River valley 247, 248 large-scale 17, 19, 295 Connecticut River 2, 9 Big Jaloman River 251 length 200 continuity equation 216 Big Stone moraine 114 Martian megaflood, outflow 23, 24, 27, convection 203 Black Sea 5, 7–8, 154 36, 297–298 convex features 80, 178 Bond crater 215 Missoula Flood 300 cooling 204 Bonneville flood (see floods, Bonneville) outflow channels 290, 306 Copernicus crater 219 Bosphorus Strait 8, 136 piping 137 Coprates Chasm 198 boulders roughness 295 Cordilleran Ice Sheet 3–4, 65 armour 106 sand-dominated beds 296 corrosion bars (see bedforms, bars) sapping Cottonwood spillway berm 248 sides 297 coulees 14, 67 clusters 276–281, 283, 286 slope 196, 198, 199, 200, 217, 276, Coulomb friction 268 lag 108, 115, 116 295, 297, 298, 299 Coveville level 122 braided morphology 196 small-scale 194 Crab Creek, Washington, USA 67 Bretz, J Harlen 1, 2, 65, 176 sources 290–291 crater counting British Columbia, Canada 133, 134 steep channels 296 Crater Lake, Oregon, USA Brule spillway subchannels 298 crater paleolakes (see lakes) burial 195 tunnel channels 86–88, 90, 91, 92–94, creationism 2 burst-and-sweep cycles 260 99 creation science 2 butte-and-basin scabland 71 water level 298 critical flow 21–22, 140 width 198, 199, 200, 218, 298 Crooked Creek, central Oregon, USA 134 C14 dating channelised flow cross-lamination (see lamination) caldera 52 chaos, chaotic terrain 23, 34, 197, 201, cross-stratification (see stratification) ice-filled 60 211, 213, 214, 216, 219, 290, 294 cryosphere 197, 201, 203, 204, 291, 293, calorimeter, natural 53 Chemal 247 294, 297, 301, 303, 305 Calumet level 116, 118 Cheney–Palouse Tract 66, 69 erosion of 303–304, 305 canyons 211, 213, 214 Chezy´ (friction) formula/coefficient 267, cut-and-fill structures 255, 257 ice 60 268, 269, 270 Capri Chasma 175–177, 214 Chia Crater 183 Dadu River, China 131 carbon dioxide 204, 205, 293–294 Chicago outlet 116, 117, 118 Daga Vallis 175–177 Cascade Range, Oregon, USA 134 Chile 227 dams Caspian Sea 134 China 130 beach berms (see also ice, dams) cataclysmic flooding 243, 244 Chryse Colles 186 compromised dams 211 cataracts (see dry cataracts, Chryse Planitia 172 constructed dams 129, 138, 143 waterfalls) 14, 20, 21 Chryse trough 213, 214 earthen dams 137, 211 catastrophism 1 Chuja basin 244, 246 experimental breaching 137 cavitation 174, 300–302, 306 Chuja palaeolake failure 129, 137–138, 209, 210, 213, Cedar Buttes lava flow 132 Chuja River valley 23, 34, 246, 247, 248, 220 Cenozoic 244, 245 249, 251, 262 glacial dams 209, 211 Ceraunius Fossae 194 Chuja–Kuray floods Gros Ventre landslide dam failure 137 Cerberus Fossae 198, 199, 200, 201, 204, Chuja–Kuray palaeolake 5 hyaloclastite dam 132 291, 293 chute–pool 20, 21 incision 214 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-86852-5 - Megaflooding on Earth and Mars Edited by Devon M. Burr, Paul A. Carling and Victor R. Baker Index More information 314 Index dams (cont.) peak 138–144, 145, 210–211, 213, Europe 130 Kuray ice dam 141 214, 275, 290, 298 evaporation, Mars 294, 302, 303, 305 landslide dams 129–131, 132, 137, rate(s) 201, 218, 291–292, 301 exhumation 195 138, 140, 141, 142, 143, 144, 145 dissolution 15, 16 explosive boiling 54 lava-flow dams 129, 132 downcutting, episodic outlet 106 Eyjafjallajokull¨ (ice cap) 265, 266, 267, Missoula ice dam 140 downstream fining 248 268, 270 moraine dams 50, 134, 137, 138, 144, drainage density 220 145, 146 drainage integration 134, 136 facies natural dams 128 drop-stones 261 fall and pool structure 296 Nurek rockfill dam, Tajikistan 129 drumlins 78, 80, 85–88, 89, 92, 94, 95, fans 67–68 rock-material dams 128 96, 97–98 Ephrata Fan 67, 73–74 stability 131, 137, 138, 143 dry cataracts terraced fan 198 unconsolidated dams 209 Dry Falls 72 faults, faulting (see also graben) 195, Usoi landslide dam, Tajikistan 129, Martian 176, 181, 182–183 202, 203, 246 145 Potholes 65 fault blocks 199 volcanogenic 131–132, 142 dunes (see bedforms, giant current Fauskheiði 269 Dana, James D.
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  • Explosive Lava‐Water Interactions in Elysium Planitia, Mars: Geologic and Thermodynamic Constraints on the Formation of the Tartarus Colles Cone Groups Christopher W

    Explosive Lava‐Water Interactions in Elysium Planitia, Mars: Geologic and Thermodynamic Constraints on the Formation of the Tartarus Colles Cone Groups Christopher W

    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, E09006, doi:10.1029/2009JE003546, 2010 Explosive lava‐water interactions in Elysium Planitia, Mars: Geologic and thermodynamic constraints on the formation of the Tartarus Colles cone groups Christopher W. Hamilton,1 Sarah A. Fagents,1 and Lionel Wilson2 Received 16 November 2009; revised 11 May 2010; accepted 3 June 2010; published 16 September 2010. [1] Volcanic rootless constructs (VRCs) are the products of explosive lava‐water interactions. VRCs are significant because they imply the presence of active lava and an underlying aqueous phase (e.g., groundwater or ice) at the time of their formation. Combined mapping of VRC locations, age‐dating of their host lava surfaces, and thermodynamic modeling of lava‐substrate interactions can therefore constrain where and when water has been present in volcanic regions. This information is valuable for identifying fossil hydrothermal systems and determining relationships between climate, near‐surface water abundance, and the potential development of habitable niches on Mars. We examined the western Tartarus Colles region (25–27°N, 170–171°E) in northeastern Elysium Planitia, Mars, and identified 167 VRC groups with a total area of ∼2000 km2. These VRCs preferentially occur where lava is ∼60 m thick. Crater size‐frequency relationships suggest the VRCs formed during the late to middle Amazonian. Modeling results suggest that at the time of VRC formation, near‐surface substrate was partially desiccated, but that the depth to the midlatitude ice table was ]42 m. This ground ice stability zone is consistent with climate models that predict intermediate obliquity (∼35°) between 75 and 250 Ma, with obliquity excursions descending to ∼25–32°.