Faint Dark Halo
A type of crater-associated radar-dark diffuse feature on Venus that is relatively small, is patchy, and has irregular planform.
A type of crater-associated radar-dark diffuse feature.
Patchy radar-dark areas around impact craters of Venus. Faint halos seem to be certainly visible but do not differ significantly in darkness from the neighboring plains (Basilevsky and Head 2002). Some very faint remnants of dark deposits can be found on stretched images on many craters classified as having no dark halo, so the boundary between the craters with no halo and with faint halo sometimes may be disputable.
Faint dark halos (FH), like other crater-associated radar-dark diffuse features on Venus, are apparent on radar images due to the presence of fine-grained material on the surface. These mantles are expected to be rather thin (Bondarenko and Head 2004). They, supposedly, are remnants of dark halos or radar dark parabolas...
KeywordsRadar Image Impact Crater Mantle Material Chemical Weathering Dark Halo
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