Ridges and tidal stress on Io

By: , and 



Sets of ridges of uncertain origin are seen in twenty-nine high-resolution Galileo images, which sample seven locales on Io. These ridges are on the order of a few kilometers in length with a spacing of about a kilometer. Within each locale, the ridges have a consistent orientation, but the orientations vary from place to place. We investigate whether these ridges could be a result of tidal flexing of Io by comparing their orientations with the peak tidal stress orientations at the same locations. We find that ridges grouped near the equator are aligned either north–south or east–west, as are the predicted principal stress orientations there. It is not clear why particular groups run north–south and others east–west. The one set of ridges observed far from the equator (52° S) has an oblique azimuth, as do the tidal stresses at those latitudes. Therefore, all observed ridges have similar orientations to the tidal stress in their region. This correlation is consistent with the hypothesis that tidal flexing of Io plays an important role in ridge formation.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Ridges and tidal stress on Io
Series title Icarus
DOI 10.1016/j.icarus.2004.01.003
Volume 169
Issue 1
Year Published 2004
Language English
Publisher Elsevier
Contributing office(s) Astrogeology Science Center
Description 16 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Icarus
First page 111
Last page 126