American Geophysical Union, Journal of Geophysical Research: Planets, 3(119), p. 395-403
DOI: 10.1002/2013je004526
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[1] Crosscutting relationships of tectonic lineaments on Europa record the history of surface deformation. We mapped the displacement and orientation of older features crosscut by two types of lineaments: bands and double ridges. These measurements allow us to determine both the strike-perpendicular and strikeparallel displacement along investigated features. Double ridges record both ridge-perpendicular contraction and expansion, with a mean of 0.16 ± 0.06 km of contraction based on the analysis of sixteen double ridges. Bands record expansion, with a mean of 3.33 ± 0.27 km for the six bands analyzed, but with perpendicular displacement less than their apparent morphologic widths of 324 km. The implied global surface strain for double ridges (including those that expand) and bands is 2.22 ± 0.76% contraction and 7.60 ± 3.7% expansion, respectively. Double ridges thus may accommodate part of the surface expansion recorded by bands. Most current models for double ridges do not predict contraction. The models that satisfy the observations for bands are “slow spreading” models, cryovolcanism, and folding.