Resurfacing history of the northern plains of Mars based on geologic mapping of Mars Global Surveyor data

Abstract

Geologic mapping of the northern plains of Mars, based on Mars Orbiter Laser Altimeter topography and Viking and Mars Orbiter Camera images, reveals new insights into geologic processes and events in this region during the Hesperian and Amazonian Periods. We propose four successive stages of lowland resurfacing likely related to the activity of near‐surface volatiles commencing at the highland‐lowland boundary (HLB) and progressing to lower topographic levels as follows (highest elevations indicated): Stage 1, upper boundary plains, Early Hesperian, <−2.0 to −2.9 km; Stage 2, lower boundary plains and outflow channel dissection, Late Hesperian, <−2.7 to −4.0 km; Stage 3, Vastitas Borealis Formation (VBF) surface, Late Hesperian to Early Amazonian, <−3.1 to −4.1 km; and Stage 4, local chaos zones, Early Amazonian, <−3.8 to −5.0 km. At Acidalia Mensa, Stage 2 and 3 levels may be lower (<−4.4 and −4.8 km, respectively). Contractional ridges form the dominant structure in the plains and developed from near the end of the Early Hesperian to the Early Amazonian. Geomorphic evidence for a northern‐plains‐filling ocean during Stage 2 is absent because one did not form or its evidence was destroyed by Stage 3 resurfacing. Remnants of possible Amazonian dust mantles occur on top of the VBF. The north polar layered deposits appear to be made up of an up to kilometer‐thick lower sequence of sandy layers Early to Middle Amazonian in age overlain by Late Amazonian ice‐rich dust layers; both units appear to have outliers, suggesting that they once were more extensive.

Comparison of geophysical investigations for detection of massive ground ice (pingo ice)

“…Delineating massive ice from frozen ground is useful information for Martian permafrost studies. A wide variety of pingo forms have been tentatively identified on Mars [Lucchitta, 1981;Cabrol et al, 2000;Rice et al, 2002;Tanaka et al, 2003;Sakimoto, 2005;Soare et al, 2005]. An analogue study and geophysical investigations of terrestrial pingos would provide support in correct identification of pingos on Mars.…”

The stratigraphy and history of Mars' northern lowlands through mineralogy of impact craters: A comprehensive survey

“…The Vastitas Borealis Formation (VBF), a widespread sedimentary unit on the surface of the northern lowlands, probably represents one of the final stages of water-related sedimentary activity. The VBF has been suggested to have resulted from either volatile expulsion from the compaction of a fluid-laden sedimentary unit [Salvatore and Christensen, 2014b], local periglacial processes acting on outflow channel sediments and other older plain materials [Tanaka et al, 2003], sublimation residues , or ocean sediments [Parker et al, 1989[Parker et al, , 1993Baker et al, 1991]. On the surface of the Vastitas Borealis Formation many geomorphic features that could be related to aqueous activity have been identified, including polygonal troughs for ice/volatile-related processes [McGill and Hills., 1992;Hiesinger and Head, 2000;Yoshikawa, 2003;Mangold et al, 2004] and conical and domical features hypothesized to be mud volcanoes or springs [Farrand et al, 2005;Oehler and Allen, 2010].…”

“…The northern lowlands of Mars preserve a long-term record of Mars' geologic history, including heavily cratered Noachian basement [Frey et al, 2002], Hesperian outflow channels and/or possible ocean deposits [Tanaka et al, 2003;Parker et al, 1993], widespread Hesperian lava flows , and Amazonian surface sedimentary/volcanic geomorphic structures (cones, knobs, polygons, etc. ) [Frey et al, 1979;Lucchitta et al, 1986;Farrand et al, 2005;Oehler and Allen, 2012].…”

Arecibo radar imagery of Mars: The major volcanic provinces

“…Perhaps the most striking radar feature is the large bright wedge (29-A) centered at 206°E, 18°N. The feature corresponds to a flat-floored topographic depression that is mapped by Tanaka et al (2003b) as being older than the surrounding higher units. Orbiter imagery shows this floor to be covered with platy-ridged lava flows (Tanaka et al, 2005).…”