{"type": "FeatureCollection", "features": [{"id": "10.1029/2018JE005899", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:17:25Z", "type": "Journal Article", "created": "2020-03-09", "title": "Initiation and Flow Conditions of Contemporary Flows in Martian Gullies", "description": "

<p>Understanding the initial and flow conditions of contemporary flows in Martian gullies, generally believed to be triggered and fluidized by CO<sub>2</sub> sublimation, is crucial for deciphering climate conditions needed to trigger and sustain them. We employ the RAMMS (RApid Mass Movement Simulation) debris flow and avalanche model to back-calculate initial and flow conditions of recent flows in three gullies in Hale crater. We infer minimum release depths of 1.0–1.5 m and initial release volumes of 100–200 m<sup>3</sup>. Entrainment leads to final flow volumes that are 2.5–5.5 times larger than initially released, and entrainment is found necessary to match the observed flow deposits. Simulated mean cross-channel flow velocities decrease from 3–4 m s<sup>-1</sup> to ~1 m s<sup>-1</sup> from release area to flow terminus, while flow depths generally decrease from 0.5–1 m to 0.1–0.2 m. The mean cross-channel erosion depth and deposition thicknesses are _0.1–0.3 m. Back-calculated dry-Coulomb friction ranges from 0.1 to 0.25 and viscous turbulent friction between 100–200 m s<sup>-2</sup>, which are values similar to those of granular debris flows on Earth. These results suggest that recent flows in gullies are fluidized to a similar degree as are granular debris flows on Earth. Using a novel model for mass-flow fluidization by CO<sub>2</sub> sublimation we are able to show that under Martian atmospheric conditions very small volumetric fractions of CO<sub>2</sub> of ~1% within mass flows may indeed yield sufficiently large gas fluxes to cause fluidization and enhance flow mobility.</p>

", "keywords": ["Atmospheric Science", "550", "[SDU.STU.GM] Sciences of the Universe [physics]/Earth Sciences/Geomorphology", "0211 other engineering and technologies", "Soil Science", "Mars", "Hale crater", "02 engineering and technology", "Aquatic Science", "carbon dioxide; gullies; Hale crater; Mars; modeling; RAMMS", "551", "Oceanography", "01 natural sciences", "[SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology", "Geochemistry and Petrology", "Earth and Planetary Sciences (miscellaneous)", "SDG 13 - Climate Action", "Research Articles", "Water Science and Technology", "Earth-Surface Processes", "0105 earth and related environmental sciences", "Ecology", "Palaeontology", "carbon dioxide", "Forestry", "modeling", "RAMMS", "Geophysics", "Space and Planetary Science", "13. Climate action", "[SDU.STU.PL] Sciences of the Universe [physics]/Earth Sciences/Planetology", "gullies"]}, "links": [{"href": "http://dro.dur.ac.uk/28802/1/28802.pdf"}, {"href": "http://dro.dur.ac.uk/28802/2/28802.pdf"}, {"href": "https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018JE005899"}, {"href": "https://doi.org/10.1029/2018JE005899"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Geophysical%20Research%3A%20Planets", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1029/2018JE005899", "name": "item", "description": "10.1029/2018JE005899", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1029/2018JE005899"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-08-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Hale+crater&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Hale+crater&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Hale+crater&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Hale+crater&offset=1", "hreflang": "en-US"}], "numberMatched": 1, "numberReturned": 1, "distributedFeatures": [], "timeStamp": "2026-05-25T00:57:49.350212Z"}