Physics
Scientific paper
Dec 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002agufm.p12a0366w&link_type=abstract
American Geophysical Union, Fall Meeting 2002, abstract #P12A-0366
Physics
5415 Erosion And Weathering, 5470 Surface Materials And Properties, 5475 Tectonics (8149)
Scientific paper
Recently Burr et al. (Recent aqueous floods from the Cerberus Fossae, Mars. GRL 29, 13-1 to 13-4, 2002, @ 0094-8276, 2001GL013345) described the Athabasca Valles channel system as being produced by a water flood and identified the source as segments of the Cerberus Fossae system, graben-like fractures trending ~SE-NW in Elysium. We have examined the source areas in detail and also investigated the large-scale structure of the Cerberus Fossae. We infer that the fossae are produced by lateral injection of ~200 m wide dikes radiating from Elysium. Stresses due to dike injection fractured the overlying cryosphere and water escaped from an underlying pressurized aquifer by travelling up the resulting fracture. Topography in the source area suggests that water was mainly released from a pair of fractures roughly aligned along strike and totalling ~20 km in length. We estimate that the water formed a ~100 m high linear fountain over its fissure vent, causing it to flow uphill for ~6 km against a ~0.1 degree regional slope before spreading sideways and back downhill around the ends of the active fractures, eroding a ~50 m deep, ~10-20 km wide, ~30 km long depression in the process. Analysis of the dynamics suggests that the total water volume flux estimated by Burr et al., ~1-2 million cubic meters per second, could be consistent with the eroded zone if the fracture releasing the water was ~3 m wide with water flowing up it at ~30 m/s. Feeding this water release, however, even invoking the most favorable aquifer geometry and a pressure gradient driven by a topographic water head involving the ~800-km distant Elysium Mons edifice, requires the aquifer to be remarkably permeable. In any case, it seems likely that some of the presently observed post-flood depth of the fossae is due to collapse and water erosion aided by melting of cryosphere ice by magmatic heat, in some places revealing the top of the underlying dike.
Head James W.
Mitchell Karl L.
Wilson Leslie
No associations
LandOfFree
Cerberus Fossae and Athabasca Valles: Dike Formation, Cryosphere Cracking and Aqueous Flooding does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cerberus Fossae and Athabasca Valles: Dike Formation, Cryosphere Cracking and Aqueous Flooding, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cerberus Fossae and Athabasca Valles: Dike Formation, Cryosphere Cracking and Aqueous Flooding will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1891859