Virtual Mars Globes

LHB (lowland-highland boundary) mensae


LHB mensae


Origin of name:
Deuteronilus: Second Nile (canal)
Protolinus: Fist Nile (canal)
Nilosyrtis: From Syrtis to Protonilus, an invented name
Nilokeras: The horn of the Nile
A név eredete:
Deuteronilus: második Nílus  (csatorna)
Protolinus: Első 
Nílus  (csatorna)
Nilosyrtis: A Syrtistől a Protonilusig (Schiaparelli névtalálmánya)
Nilokeras: A Nílus szarva

Geologic description and interpretation: 

Deuteronilus Mensae are primarily characterised by glacial features. It is believed that these valleys may have originated due to intense flooding by melted water ice.[1] Within Deuteronilus Mensae, polygonal mesas are prominent along with features diagnostic of Martian ‘fretted’ terrain, including lobate debris aprons, lineated valley fill, and concentric crater fill. Lobate debris aprons, as well as the valley and crater fill deposits, are considered to be geomorphic indicators of ground ice. [2] The Nilosyrtis Mensae valley system is characterised by lineated valley fill and lobate debris aprons in association with fretted terrain and fretted channels in the northern part of Arabia Terra. Fretted valleys display a multitude of characteristics typical of integrated valley glacial systems on Earth (multiple theater-headed, alcove-like accumulation areas; sharp arete-like ridges typical of glacial erosion; converging patterns of downslope valley flow; valley lineation patterns typical of folding and shear; wrap-around features indicative of flow around obstacles; and broad piedmont-like lobes as the valley fill extends out into the northern lowlands).[3]

The aprons [of Deuteronilus Mensae] likely result from mass wasting of the walls of the Noachis Terra unit, which suggests that the Noachis Terra unit is vola tile rich in this area. The young unit age may indicate that the mass-wasting process remains relatively active; initial development of the unit, however, is uncertain and may extend as far back in time as the Late Hesperian.[4]

Geológiai leírás és magyarázat:
A Deuteronilus Mensae-t glaciális formakincs jellemzi. "Ősfolyamvölgyeit" olvadékvizek alakították ki. Táblahegyei a marsi "kimart" területek legfőbb jellemzői, a maguk lebenyes törmelékszoknyáival, vonalas völgykitöltő üledékeikkel és koncentrikus kráterbelseji üledékekkel. Ezeket mind a talajjéggel hozzák kapcsolatba. 


[1] ESA website: Breathtaking views of Deuteronilus Mensae on Mars 21 May 2007  http://www.esa.int/esaSC/SEMBS5V681F_index_0.html

[2] GEOLOGIC MAP OF MTM 35337, 40337, AND 45337 QUADRANGLES, DEUTERONILUS MENSAE REGION OF MARS. Frank C. Chuang and David A. Crown, Abstracts of the Annual Meeting of Planetary Geologic Mappers, Tucson, AZ 2007 Open-File Report 2007–1233

[3] Head, J. W., A. L. Nahm, D. R. Marchant, and G. Neukum (2006), Modification of the dichotomy boundary on Mars by Amazonian mid-latitude regional glaciation, Geophys. Res. Lett., 33, L08S03, doi:10.1029/2005GL024360.  http://www.planetary.brown.edu/pdfs/3240.pdf

[4] Tanaka, Kenneth L.; Skinner, James A., Jr.; Hare, Trent M. 2005: Geologic Map of the Northern Plains of Mars. Scientific Investigations Map Report Number 2888 USGS  ftp://ftpflag.wr.usgs.gov/dist/pigpen/mars /geology/NPlains_geology_SIM2888_2005_pamphlet.pdf

Deuteronilus Colles is interpreted to be the eroded remnant of a crater interior structure, includes individual and clustered, irregularly-shaped, rounded knobs and smooth to hummocky deposits with lobate margins adjacent to knobs (lobate debris aprons). [1]

[1] GEOLOGIC MAPPING OF HIGHLAND/LOWLAND BOUNDARY ZONES: EASTERN HELLAS PLANITIA AND DEUTERONILUS MENSAE, MARS. David A. Crown, Leslie F. Bleamaster, III, and Frank . Chuang,

2006: Abstracts of the Annual Meeting of Planetary Geologic Mappers, Nampa, Idaho 2006 Open-File Report 2006-1263