The tectonic sequence in the anti-jovian area covered by regional
mapping images front Galileo's orbit E15 is determined from a study
of cross-cutting relationships among lineament features. The sequence
is used to test earlier results from orbit G1, based on lower resolution
images, which appeared to display a progressive change in azimuthal
orientation over about 90 degrees in a clockwise sense. Such a progression
is consistent with expected stress variations that would accompany
plausible non-synchronous rotation. The more recent data provide
a more complete record than the G1 data did. We find that to fit
the sequence into a continual clockwise change of orientation would
require at least 1000 degrees (> 5 cycles) of azimuthal rotation.
If due to non-synchronous rotation of Europa, this result implies
that we are seeing back further into the tectonic record than the
G1 results had suggested. The three sets of orientations found by
Geissler et al. now appear to have been spaced out over several cycles,
not during a fraction of one cycle. While our more complete sequence
of lineament formation is consistent with non-synchronous rotation,
a statistical test shows that it cannot be construed as independent
evidence. Other lines of evidence do support non-synchronous rotation,
but azimuths of crack sequences do not show it, probably because
only a couple of cracks form in a given region in any given non-synchronous
rotation period. (c) 2004 Elsevier Inc. All rights reserved.
%0 Journal Article
%1 Sarid2005
%A Sarid, A. R.
%A Greenberg, R.
%A Hoppa, G. V.
%A Brown, D. M.
%A Geissler, P.
%D 2005
%J Icarus
%K FEATURES; NONSYNCHRONOUS PATTERNS ROTATION; STRESSES; TIDAL
%N 2
%P 469--479
%T Crack azimuths on Europa: the G1 lineament sequence revisited
%V 173
%X The tectonic sequence in the anti-jovian area covered by regional
mapping images front Galileo's orbit E15 is determined from a study
of cross-cutting relationships among lineament features. The sequence
is used to test earlier results from orbit G1, based on lower resolution
images, which appeared to display a progressive change in azimuthal
orientation over about 90 degrees in a clockwise sense. Such a progression
is consistent with expected stress variations that would accompany
plausible non-synchronous rotation. The more recent data provide
a more complete record than the G1 data did. We find that to fit
the sequence into a continual clockwise change of orientation would
require at least 1000 degrees (> 5 cycles) of azimuthal rotation.
If due to non-synchronous rotation of Europa, this result implies
that we are seeing back further into the tectonic record than the
G1 results had suggested. The three sets of orientations found by
Geissler et al. now appear to have been spaced out over several cycles,
not during a fraction of one cycle. While our more complete sequence
of lineament formation is consistent with non-synchronous rotation,
a statistical test shows that it cannot be construed as independent
evidence. Other lines of evidence do support non-synchronous rotation,
but azimuths of crack sequences do not show it, probably because
only a couple of cracks form in a given region in any given non-synchronous
rotation period. (c) 2004 Elsevier Inc. All rights reserved.
@article{Sarid2005,
abstract = {The tectonic sequence in the anti-jovian area covered by regional
mapping images front Galileo's orbit E15 is determined from a study
of cross-cutting relationships among lineament features. The sequence
is used to test earlier results from orbit G1, based on lower resolution
images, which appeared to display a progressive change in azimuthal
orientation over about 90 degrees in a clockwise sense. Such a progression
is consistent with expected stress variations that would accompany
plausible non-synchronous rotation. The more recent data provide
a more complete record than the G1 data did. We find that to fit
the sequence into a continual clockwise change of orientation would
require at least 1000 degrees (> 5 cycles) of azimuthal rotation.
If due to non-synchronous rotation of Europa, this result implies
that we are seeing back further into the tectonic record than the
G1 results had suggested. The three sets of orientations found by
Geissler et al. now appear to have been spaced out over several cycles,
not during a fraction of one cycle. While our more complete sequence
of lineament formation is consistent with non-synchronous rotation,
a statistical test shows that it cannot be construed as independent
evidence. Other lines of evidence do support non-synchronous rotation,
but azimuths of crack sequences do not show it, probably because
only a couple of cracks form in a given region in any given non-synchronous
rotation period. (c) 2004 Elsevier Inc. All rights reserved.},
added-at = {2009-11-03T20:21:25.000+0100},
author = {Sarid, A. R. and Greenberg, R. and Hoppa, G. V. and Brown, D. M. and Geissler, P.},
biburl = {https://www.bibsonomy.org/bibtex/2241a348828697dbc373058435f974038/svance},
citedreferences = {GEISSLER PE, 1998, Icarus, V135, P107 ; GEISSLER PE, 1998, Nature, V391, P368 ; Greenberg R, 1984, Icarus, V58, P186 ; Greenberg R, 1998, Icarus, V135, P64 ; Greenberg R, 2002, CELEST MECH DYN ASTR, V83, P35 ; HELFENSTEIN P, 1985, Icarus, V61, P175 ; HOPPA G, 1999, Icarus, V137, P341 ; HOPPA G, 1999, Icarus, V141, P287 ; HOPPA GV, 1999, Science, V285, P1899 ; HOPPA GV, 2001, Icarus, V153, P208 ; SARID AR, 2002, Icarus, V158, P24 ; SARID AR, 2004, Icarus, V168, P144 ; ZAHNLE K, 2003, Icarus, V163, P263},
interhash = {9d541c738085d9c8a3125a14b1140b83},
intrahash = {241a348828697dbc373058435f974038},
journal = {Icarus},
keywords = {FEATURES; NONSYNCHRONOUS PATTERNS ROTATION; STRESSES; TIDAL},
number = 2,
owner = {svance},
pages = {469--479},
timestamp = {2009-11-03T20:22:12.000+0100},
title = {Crack azimuths on Europa: the G1 lineament sequence revisited},
volume = 173,
year = 2005
}