Change search
ReferencesLink to record
Permanent link

Direct link
Analysis of Gully Formations in the Martian Northern Hemisphere
2004 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

This thesis comprises a survey of the intriguing gully formations in the martian northern hemisphere. Data from the instruments onboard the satellite Mars Global Surveyor were downloaded and processed through different programming steps. Among 14722 images taken by the Mars Orbiter Camera 133 were found to reveal gully features. The different gully characteristics such as alcoves, channels and aprons were measured and the mean lengths were calculated to be, respectively, 570 m, 180 m and 996 m. Also, the gullies were found to be oriented in all directions, although preferentially on equator-facing slopes. The gullies appear to be more common in the mid-latitudes between 36°N and 45°N, but spread out over all longitudes, with some clustering in Acidalia Planitia and Utopia Planitia. Some 73% of the gullies in MOC images were found on crater walls, which are rather old geological features. Crater impacts could be seen on some of the gullies, suggesting that they are older than the gullies in the southern hemisphere, since the latter generally lack superposed impact craters. Additionally the gullies in the north appear to be more eroded than those in the south, which strengthens the theory that they are older than the southern ones. However, other mechanisms, such as different erosion rates in the north, or more or less dust mantling due to atmospheric conditions, could also explain this phenomenon. Some 87% of the gullies are associated with visible strata layers in their alcove regions suggesting that the fluid that carved out the gullies came from pockets within those layers in the subsurface. Different models of gully formations are discussed, and it is argued that the aquifer model is favoured due to the morphology found at the gully sites.

Place, publisher, year, edition, pages
2004.
Keyword [en]
Technology, gully, northern hemisphere, Mars, MGS, MOC
Keyword [sv]
Teknik
Identifiers
URN: urn:nbn:se:ltu:diva-46456ISRN: LTU-EX--04/203--SELocal ID: 4184e48e-93c5-4dc5-a24e-2457ebb2474eOAI: oai:DiVA.org:ltu-46456DiVA: diva2:1019770
Subject / course
Student thesis, at least 30 credits
Educational program
Space Engineering, master's level
Examiners
Note
Validerat; 20101217 (root)Available from: 2016-10-04 Created: 2016-10-04Bibliographically approved

Open Access in DiVA

No full text

Search outside of DiVA

GoogleGoogle Scholar

Total: 1 hits
ReferencesLink to record
Permanent link

Direct link