Possible Liquid-like Water Produced Seepage Features on Mars

Introduction: Various polar albedo features appear on Mars in springtime, like spiders [1, 2, 3, 4], dark spots [5, 6], Dalmatian spots [7], and Dark Dune Spots (DDSs) [8]. Some of them formed probably by CO2 jets [9] others possibly by flow-like process [8, 10, 11]. The seasonal behavior of polar frost may give insight into the type of ice on the cap [12], characteristics of waterice annulus [13], frost outliers [14], and even into the climate changes [15]. We studied the seasonal behavior of the flow-like process at the DDS-seepages [10, 11, 16]. In our previous works we analyzed the possible interfacial water related seepagelike features at south [17], then our team [18] and other groups [19] investigated their northern counterparts. characteristics “large” DDSs “small” DDSs diameter 5-25 m <5 m morphology Dark interior, diffuse ring-like halo on horizontal plains, and slope streaks on steep surfaces Simple spots, rarely with slope streaks and ring-like halo