%0 Journal Article %1 Greenberg2003a %A Greenberg, R. %A Leake, M. A. %A Hoppa, G. V. %A Tufts, B. R. %D 2003 %J Icarus %K CHAOTIC FAULTS; FEATURES; ICE REGION SHELL; STRIKE-SLIP TERRAIN; %N 1 %P 102--126 %T Pits and uplifts on Europa %V 161 %X A survey of depression and uplift features on Europa, based on Galileo regional mapping images, shows that these features come in a wide range of sizes, with numbers increasing greatly with decreasing size, down to the limits of resolution. Size distributions are similar in the northern leading and southern trailing hemispheres, where they are distinctly different from the southern leading and northern trailing hemispheres, suggesting an oblique, antipodal symmetry pattern, similar to that of chaotic and tectonic terrain. This pattern is suggestive of polar wander. Uplifts are usually polygonal or irregular in shape and rarely are cracked. Patches of chaotic terrain, which we had surveyed earlier, are not included in the current study because their topography is generally unclear, and because there is no a priori known genetic linkage with the pits and uplifts. These results contradict generalizations based on the earlier "pits, spots, and domes" (PSD) taxonomy. Most of the type examples for PSDs were simply patches of chaotic terrain selected from a limited portion of their full size range. The use of the term lenticula to collectively describe PSDs is inconsistent with the IAU definition of lenticula: a small dark spot seen at low resolution. Pits and uplifts do not correlate with lenticulae, although chaos often does. Properties of PSDs that have been widely cited as primary evidence for convective upwelling in thick ice (e.g., that uplifts are generally dome-shaped and often cracked; that pits and domes are regularly spaced; that there is a typical diameter of similar to10 km) were premature and not supported by subsequent data. Most pits and uplifts are less than 10 km across so, if they formed by diapirism or convective upwelling, the sources must have been very shallow, less than 5 km deep. How they actually formed remains unknown. (C) 2003 Elsevier Science (USA). All rights reserved.

@article{Greenberg2003a, abstract = {A survey of depression and uplift features on Europa, based on Galileo regional mapping images, shows that these features come in a wide range of sizes, with numbers increasing greatly with decreasing size, down to the limits of resolution. Size distributions are similar in the northern leading and southern trailing hemispheres, where they are distinctly different from the southern leading and northern trailing hemispheres, suggesting an oblique, antipodal symmetry pattern, similar to that of chaotic and tectonic terrain. This pattern is suggestive of polar wander. Uplifts are usually polygonal or irregular in shape and rarely are cracked. Patches of chaotic terrain, which we had surveyed earlier, are not included in the current study because their topography is generally unclear, and because there is no a priori known genetic linkage with the pits and uplifts. These results contradict generalizations based on the earlier "pits, spots, and domes" (PSD) taxonomy. Most of the type examples for PSDs were simply patches of chaotic terrain selected from a limited portion of their full size range. The use of the term lenticula to collectively describe PSDs is inconsistent with the IAU definition of lenticula: a small dark spot seen at low resolution. Pits and uplifts do not correlate with lenticulae, although chaos often does. Properties of PSDs that have been widely cited as primary evidence for convective upwelling in thick ice (e.g., that uplifts are generally dome-shaped and often cracked; that pits and domes are regularly spaced; that there is a typical diameter of similar to10 km) were premature and not supported by subsequent data. Most pits and uplifts are less than 10 km across so, if they formed by diapirism or convective upwelling, the sources must have been very shallow, less than 5 km deep. How they actually formed remains unknown. (C) 2003 Elsevier Science (USA). All rights reserved.}, added-at = {2009-11-03T20:21:25.000+0100}, author = {Greenberg, R. and Leake, M. A. and Hoppa, G. V. and Tufts, B. R.}, biburl = {https://www.bibsonomy.org/bibtex/26941123401b4aeeb767d0863dce5a9ce/svance}, citedreferences = {*INT ASTR UN, 1997, GAZ PLAN NOM ; BELTON MJS, 1996, Science, V274, P377 ; CHAPMAN CR, 1996, EUR OC C SAN JUAN CA, P19 ; CHAPMAN CR, 1997, LUNAR PLANET SCI, V28 ; FAGENTS SA, 2000, Icarus, V144, P54 ; Greeley R, 2000, J GEOPHYS RES-PLANET, V105, P22559 ; Greenberg R, 1998, Icarus, V135, P64 ; Greenberg R, 1999, Icarus, V141, P263 ; HOPPA G, 1999, Icarus, V141, P287 ; HOPPA G, 2000, J GEOPHYS RES-PLANET, V105, P22617 ; HOPPA GV, 2001, Icarus, V151, P181 ; KADEL SD, 1998, LUNAR PLANET SCI, V29 ; OBRIEN DP, 2001, IN PRESS Icarus ; Ojakangas GW, 1989, Icarus, V81, P242 ; PAPPALARDO RT, 1998, Nature, V391, P365 ; PAPPALARDO RT, 1999, J GEOPHYS RES, V104, P24105 ; PAPPALARDO RT, 2000, LUNAR PLANET SCI, V31 ; PAPPALARDO RT, 2001, LUNAR PLANET SCI, V32 ; PROCKTER LM, 1999, J GEOPHYS RES-PLANET, V104, P16531 ; RATHBUN JA, 1998, GEOPHYS RES LETT, V25, P4157 ; RILEY J, 2000, J GEOPHYS RES-PLANET, V105, P22599 ; SARID AR, 2002, IN PRESS Icarus ; SCHENK PM, 2001, LUNAR PLANETARY SCI, V32 ; SHOEMAKER EM, 1996, EUR OC C SAN JUAN CA, P65 ; SPAUN NA, 1998, MOTTLED TERRAIN EURO ; SPAUN NA, 1999, LUNAR PLANETARY SCI, V30 ; THOMSON RE, 2001, J GEOPHYS RES-PLANET, V106, P12355 ; TUFTS R, 1998, THESIS U ARIZONA TUC ; WILLIAMS KK, 1998, GEOPHYS RES LETT, V25, P4273}, interhash = {77b7e26cc513697b53f9dc3b48866bdb}, intrahash = {6941123401b4aeeb767d0863dce5a9ce}, journal = {Icarus}, keywords = {CHAOTIC FAULTS; FEATURES; ICE REGION SHELL; STRIKE-SLIP TERRAIN;}, number = 1, owner = {svance}, pages = {102--126}, timestamp = {2009-11-03T20:21:50.000+0100}, title = {Pits and uplifts on Europa}, volume = 161, year = 2003 }