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Ancient Drainage Basin of the Tharsis Region, Mars: Potential Source for Outflow Channel Systems and Putative Oceans Or Paleolakes

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Ancient Drainage Basin of the Tharsis Region, Mars: Potential Source for Outflow Channel Systems and Putative Oceans Or Paleolakes University of Central Florida STARS Faculty Bibliography 2000s Faculty Bibliography 1-1-2001 Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes J. M. Dohm J. C. Ferris V. R. Baker R. C. Anderson T. M. Hare FindSee next similar page works for additional at: https:/ authors/stars.libr ary.ucf.edu/facultybib2000 University of Central Florida Libraries http://library.ucf.edu This Article is brought to you for free and open access by the Faculty Bibliography at STARS. It has been accepted for inclusion in Faculty Bibliography 2000s by an authorized administrator of STARS. For more information, please contact [email protected]. Recommended Citation Dohm, J. M.; Ferris, J. C.; Baker, V. R.; Anderson, R. C.; Hare, T. M.; Strom, R. G.; Barlow, N. G.; Tanaka, K. L.; Klemaszewski, J. E.; and Scott, D. H., "Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes" (2001). Faculty Bibliography 2000s. 7973. https://stars.library.ucf.edu/facultybib2000/7973 Authors J. M. Dohm, J. C. Ferris, V. R. Baker, R. C. Anderson, T. M. Hare, R. G. Strom, N. G. Barlow, K. L. Tanaka, J. E. Klemaszewski, and D. H. Scott This article is available at STARS: https://stars.library.ucf.edu/facultybib2000/7973 JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 106, NO. El2, PAGES 32,943-32,958, DECEMBER 25, 2001 Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes J. M. Dohm, • J. C. Ferris, • V. R. Baker, •,2 R. C. Anderson,3,4 T. M. Hare? R. G. Strom,2 N. G. Barlow, 6 K. L. Tanaka? J. E. Klemaszewski,? and D. H. Scott8 Abstract. Paleotopographicreconstructions based on a synthesisof publishedgeologic informationand high-resolutiontopography, including topographic profiles, reveal the potential existenceof an enormousdrainage basin/aquifer system in the easternpart of the Tharsisregion duringthe NoachianPeriod. Large topographichighs formed the margin of the giganticdrainage basin. Subsequently, lavas, sediments, and volatilespartly infilled the basin,resulting in an enormousand productiveregional aquifer. The stacked sequencesof water-bearingstrata were then deformedlocally and, in places,exposed by magmatic-drivenuplifts, tectonicdeformation, and erosion.This basin model providesa potential sourceof water necessaryto carve the large outflow channelsystems of the Tharsisand surroundingregions and to contributeto the formation of putative northern- plainsocean(s) and/or paleolakes. 1. Introduction development(Plates 1 and 2), includingvolcanic constructs of varyingsizes and extensive lava flow fields, large igneous plateaus, Stratigraphic, tectonic, and erosional records, compiled fault and rift systemsof varyingextent and relativeage of forma- throughgeological mapping investigations at regional and lo- tion, giganticoutflow channel systems, vast canyon systems, and cal scales,demonstrate a significantcontribution of magmatic- local and regionalcenters of tectonicactivity. Many of the local driven processesto the dynamicgeologic history of Mars [for and regionalcenters of tectonicactivity [Anderson et al., 1998, example,Mouginis-Mark, 1985; Scott and Tanaka, 1986; Gree- 2001;Anderson and Dohm, 2000]are interpretedto be the result ley and Guest,1987; Baker et al., 1991; Crownet al., 1992;Scott of magmatic-relatedactivity, including uplift, faulting,dike em- et al., 1993; Robinsonet al., 1993; Crown and Greeley,1993; placement,volcanism, and local hydrothermalactivity [Dohm et Gregget al., 1998].These processes are perhapsbest exempli- al., 1998,2000b, 2000d, 2001a; Dohm and Tanaka, 1999].The fied at Tharsis and the surroundingregions in the western geologichistory of the numerouscomponents of the Tharsismag- hemisphere[Frey, 1979; Wiseet al., 1979;Plescia and Saunders, matic complex,which has been analyzedin detail by numerous 1982; Solomon and Head, 1982; Scottand Tanaka, 1986; Morris investigators(see Plate 1), is incorporatedinto the analysesand and Tanaka, 1994; Scott and Zimbelman, 1995;Andersonet al., interpretationsthat follow. 1998, 2001; Scott et al., 1998; Golombek, 2000; Solomon and Inasmuch as the relative age of formation of the primary Head, 2000], where pulsesof magmaticactivity associated with componentsof the complexare generallyunderstood, the gen- the developmentof the Tharsis Magmatic Complex (TMC) eral stratigraphyestablished, and the high-resolutiontopogra- [e.g., Dohm et al., 2000a, 2000b] may have triggered cata- phy of present-dayMars known,the featuresand materialscan strophic floods and short-lived climatologicalperturbations be "backstripped"systematically from their presentconfigura- [Bakeret al., 1991, 2000;Baker, 2001]. tion. This provides an approximatesequential three-dimen- The Tharsis magmaticcomplex is composedof numerous sional(3-D) view of the paleotopographyat the cessationof componentsthat formed duringspecific stages of the complex's each of the five stagesof the complex'sdevelopment (Plates 3-7). Stageinformation correlates with the schemedevised by •Departmentof Hydrologyand Water Resources, University of Ar- Dohm and Tanaka [1999] (see Platesi and 2). izona, Tucson, Arizona, USA. The purposeof the 3-D visualizationand quasi-quantitative 2Lunarand Planetary Laboratory, Department of PlanetaryScience, Universityof Arizona, Tucson,Arizona, USA. backstrippingis not to generatea quantitativelyaccurate re- 3jet PropulsionLaboratory, Pasadena, California, USA. constructionof Martian paleotopographyat discrete time 4Lunarand PlanetaryLaboratory, University of Arizona,Tucson, steps.Such a reconstructionmay well be possibleat a future Arizona, USA. date when more data become available. However, the more SU.S.Geological Survey, Flagstaff, Arizona, USA. 6RobinsonObservatory, Department of Physics,University of Cen- qualitativevisualizations employed in this studyserve to sum- tral Florida, Orlando, Florida, USA. marize inferencesmade from geologicalmapping and analyses ?Departmentof Geology,Arizona State University, Tempe, Ari- and synthesisof publishedmap information.This summary, zona, USA. really an illustratedworking hypothesis,leads to the identifi- 8DeceasedAugust 9, 2000. cation of an ancient, gigantic drainage basin that persists Copyright2001 by the American GeophysicalUnion. through much of the history of the region. Moreover, the Paper number2000JE001468. drainagebasin, once identified, is found to be consistentwith 0148- 0227/01/2000JE001468509.00 a diverse series of other observations. The overall coherence of 32,943 32 944 DOHM ET AL.: ANCIENT DRAINAGE BASIN OF THE THARSIS REGION MARS Plan urn ustrale Stage Oer•od 0 5 N , Plate 1. Mars Orbiter Laser Altimeter (MOLA) shadedrelief map of the western hemisphereof Mars (courtesyof the MOLA ScienceTeam). Shown are the major geologicfeatures of the TharsisMagmatic Complex (TMC) and their stagesof development(stage assignments 1-5 of Dohm and Tanaka [1999] and Dohm et al. [2001a]correlated with the time-stratigraphicage assignment:Noachian, Hesperian, and Ama- zonian periodsof Tanaka [1986]), basedon numerousdetailed geologicinvestigations [e.g., Milton, 1974; Baker and Milton, 1974; Plesciaet al., 1980; Plesciaand Saunders,1982; Scott and Tanaka, 1986; Tanaka, 1986; Tanaka and Davis, 1988;Frey and Grant, 1990; Tanaka, 1990;Scott and Dohm, 1990a, 1990b;Baker et al., 1991; I45'tbecket al., 1991;Chapman et al., 1991;Morals et al., 1991;Lucchitta et al., 1992;DeHon, 1992;Scott, 1993; Gulick, 1993; Morals and Tanaka, 1994; Schultz and Tanaka, 1994; Rotto and Tanaka, 1995; Scott and Zimbelman,1995; Scott et al., 1995;Rice and DeHon, 1996;Chapman and Tanaka, 1996;Scott and Dohm, 1997; Scottet al., 1998;Dohm et al., 1998;Anderson et al., 1998;Dohm and Tanaka, 1999;Nelson and Greeley,1999; McKenzieand Nimmo, 1999;Anderson and Dohm, 2000; Dohm et al., 2000b; Chapmanand Lucchitta, 2000; Head et al., 2000;Baker et al., 2001;Dohm et al., 2001a,200lb;Anderson et al., 2001]. Also shownare Solisand ThaumasiaPlanae (S.P. and T.P., respectively),approximated margins of the TMC (black dashedoutline), northwesternslope valleys (NSVs), and the Noachiandrainage basin (blue dashedoutline). these observations can be considered to be a tentative confir- ing the above referencedtopographic, stratigraphic, paleoero- mation of utility for the basin hypothesis.While the quantita- sional, and paleotectonic information. This information in- tive confirmation of detailed validity for various reconstruc- cludesspatial and temporal relations amongshield volcanoes, tions is beyond the scope of this preliminary study, such igneousplateaus, magmatic-driven centers of tectonic activity, reconstructionswould be among the several possiblefollow- fault and rift systems,and lava flow fields. In this process, ons to the present study. featuresand materialsof a known relative age were systemat- ically backstrippedfrom their presentMOLA-based configu- ration, providingapproximate sequential views of the paleoto- 2. Three-Dimensional Portrayal of the pography at the cessationof each of the five stagesof the Evolution of the Tharsis Magmatic Complex complex'sdevelopment. A 3-D visualizationprogram (Bryce 4 by the MetaCreations We emphasizethat theseillustrations are qualitativeat this Corporation) providesa heuristicrepresentation of the geo- point. They representa working hypothesis,based on our in- logicalevolution of the TharsisMagmatic Complex.Although terpretationof the geologicmapping and analysesand
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