A Minimum Time for the Formation of Holden Northeast Fan, Mars

The recently discovered deposits of a channelized fan located northeast of Holden Crater preserve a history of vertical and lateral accretion and avulsion of many channels, indicating water flowed freely across the surface of the fan during its construction. These sedimentary deposits, however, do not unambiguously discriminate between a deltaic or purely riverine origin for the feature. By using a numerical model describing fan construction solely by river channels, we estimate a minimum formation time of several decades to centuries. A minimum value for the total volume of transporting fluid required to construct the fan is modest, 900 km3, and may not have required precipitation.