Topic
Ravine
About: Ravine is a research topic. Over the lifetime, 451 publications have been published within this topic receiving 9413 citations.
Papers published on a yearly basis
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Papers
TL;DR: It is shown that these gullies on Mars may result from the melting of water ice in the top few meters of the martian subsurface at high obliquity, and that above-freezing temperatures can occur in the near surface of Mars, but are only predicted at latitudes and for slope orientations corresponding to where the gullies have been observed on Mars.
Abstract: The observation of small gullies associated with recent surface runoff on Mars has renewed the question of liquid water stability at the surface of Mars. The gullies could be formed by groundwater seepage from underground aquifers; however, observations of gullies originating from isolated peaks and dune crests question this scenario. We show that these landforms may result from the melting of water ice in the top few meters of the martian subsurface at high obliquity. Our conclusions are based on the analogy between the martian gullies and terrestrial debris flows observed in Greenland and numerical simulations that show that above-freezing temperatures can occur at high obliquities in the near surface of Mars, and that such temperatures are only predicted at latitudes and for slope orientations corresponding to where the gullies have been observed on Mars.
436 citations
TL;DR: It is shown that gullies can form by the melting of water-rich snow that has been transported from the poles to mid-latitudes during periods of high obliquity within the past 105 to 106 years.
Abstract: The observation of gullies on Mars indicates the presence of liquid water near the surface in recent times1,2, which is difficult to reconcile with the current cold climate. Gullies have been proposed to form through surface runoff from subsurface aquifers1,3 or through melting of near-surface ice under warmer conditions4. But these gullies are observed to occur preferentially in cold mid-latitudes2, where the presence of liquid water is less likely, and on isolated surfaces where groundwater seepage would not be expected, making both potential explanations unsatisfactory. Here I show that gullies can form by the melting of water-rich snow that has been transported from the poles to mid-latitudes during periods of high obliquity within the past 105 to 106 years (refs 5, 6). Melting within this snow7 can generate sufficient water to erode gullies in about 5,000 years. My proposed model for gully formation is consistent with the age and location of the gullies, and it explains the occurrence of liquid water in the cold mid-latitudes as well as on isolated surfaces. Remnants of the snowpacks are still present on mid-latitude, pole-facing slopes, and the recent or current occurrence of liquid water within them provides a potential abode for life.
374 citations
TL;DR: In this article, the authors reviewed the history and principles of check-dams and discussed future theoretical and experimental studies which are needed for the further implementation of this system and showed that the amount of sediment retained by check-dam systems is the largest of all methods and the potential is promising.
278 citations
TL;DR: In this paper, the authors compared digital elevation models produced by airborne and ground-based LiDAR systems to determine their utility in quantifying volumetric soil loss due to gully erosion in a heavily degraded watershed on southwestern Santa Cruz Island in southern California.
260 citations
TL;DR: In this article, a high-resolution remote sensing system for aerial surveys by blimp or kite has been developed which meets spatial and temporal image resolutions required for short-term gully monitoring.
254 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 32 |
| 2024 | 63 |
| 2023 | 52 |
| 2022 | 88 |
| 2021 | 38 |
| 2020 | 20 |