Introduction: Current temperature and pressure conditions on Mars suggest that liquid water is unstable at the surface with respect to boiling and freezing. However, gully features, generally consisting of alcoves , channels, and debris aprons and existing in a band at mid latitudes mainly in the southern hemisphere with a possible preference for pole-facing orien-tations [1, 2], suggest liquid...

A gully is an excavation cut in the immediate footwall or hangingwall of the reef for the purpose of enabling the removal of rock from the face or providing access to the face for mining personnel or material1. The gully sidewalls and hangingwall often pose a serious stability problem in the gold and platinum mines in South Africa, since records of fatal rock-related injuries show that they are...

Intense gully erosion has sculptured remarkable channels into the Moldavian Plateau of eastern Romania, especially in its most representative subunit, Bârlad covering >8000 km2. The permanent types are: (1) discontinuous gullies, mostly located on hillslopes and (2) large continuous gullies valley bottoms. This study seeks to improve our understanding development over variable time-scales (most...

Gully erosion is a major environmental threat on the Moldavian Plateau (MP) of eastern Romania. The permanent gully systems consist two main types. These are: (1) discontinuous gullies, which are mostly located hillslopes and (2) large continuous gullies in valley bottoms. Very few studies have investigated evolution over medium to longer term. objective this study was quantitatively analyse de...

Martian gullies are geologically recent small-scale features characterised by an alcove-channel-apron morphology associated on Earth with liquid water. Since their discovery by Malin and Edgett (1), several theories have been advanced to explain their formation. These typically emphasise either groundwater processes (1, 2) or melting of ground ice or snowpack (3). The former approach has been c...

Introduction: A stereo pair of HiRISE images of a pole-facing crater slope at 38S, 218E shows many fresh looking gullies. After measuring slopes using the stereo viewing geometry, we estimate the expected fluvial discharge rates using theory from Kleinhans [1] and Ikeda [2]. We also develop a numerical model of sediment transport based on theory presented in Kleinhans [1] to determine the time ...

Liquid water is not stable under current martian surface conditions, but the presence of small gullies on the polewardfacing slopes of midto highlatitude martian surfaces suggests that erosion by liquid water might have occurred. Costard et al. (p. 110) developed a global climate model for Mars when it had a higher obliquity (about 300,000 years ago). Their model shows that more melting of the ...

Introduction: The discovery of gullies on Mars [1,2] resulted in a wide variety of proposed candidate mechanisms for formation but ensuing analyses have shown very strong latitude and orientation dependencies on their distributions [3-6]. These constraints have been interpreted to require: 1) a volatile on or near the surface as a source of liquid water, and 2) insolation and slope orientation ...