Quantitative Geomorphic Analysis Research Articles

Fluvial origin of the valley system in northern Victoria Land (Antarctica) from quantitative geomorphic analysis

A network of sinuous valleys with typical dendritic pattern characterizes northern Victoria Land (NVL) in Antarctica. Subparallel to parallel and angular to rectangular patterns are also present. Quantitative geomorphic analysis of the valley network has been carried out utilizing GIS spatial analysis. While drainage densities and drainage frequencies show low values, segments of the NVL valley network are substantially well organized, as indicated by bifurcation ratio (R b ) and direct bifurcation ratio (R bd ) parameters. All basins faithfully adhere to Horton’s laws of drainage network composition. Quantitative geomorphic analysis suggests that the valley system can be ascribed to fl uvial origin and that consequently, a morphoclimatic system completely different from that of present day must have driven its carving. The resulting data provide indications about the origin of the valley network and this invaluable information can be used for the reconstruction of earlier phases of glacial history and climatic and tectonic evolution of this signifi cant Antarctic region. Fluvial erosion enhanced the denudation of the Transantarctic Mountains from at least 55 Ma to at least the Eocene-Oligocene boundary (ca 34 Ma). Fluvial basins adapted to the tectonic structure, following the main regional fault systems. A well-developed alpine topography postdates the fl uvial morphology. Temperate glaciers were responsible for denudation until the Late Miocene. Parasitic glaciers presently mantle the previously sculpted topography. Present-day glacial erosion is negligible and denudation has been exceedingly slow since 7.5 Ma.

Identification of possible Quaternary deformation in the northeastern Mississippi Embayment using quantitative geomorphic analysis of drainage-basin asymmetry

Research Article| May 01, 2001 Identification of possible Quaternary deformation in the northeastern Mississippi Embayment using quantitative geomorphic analysis of drainage-basin asymmetry Randel Tom Cox; Randel Tom Cox 1Department of Geological Sciences, 402 Smith Building, University of Memphis, Memphis, Tennessee 38152, USA Search for other works by this author on: GSW Google Scholar Roy B. Van Arsdale; Roy B. Van Arsdale 1Department of Geological Sciences, 402 Smith Building, University of Memphis, Memphis, Tennessee 38152, USA Search for other works by this author on: GSW Google Scholar James B. Harris James B. Harris 2Department of Geology, Millsaps College, Jackson, Mississippi 39210, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2001) 113 (5): 615–624. https://doi.org/10.1130/0016-7606(2001)113<0615:IOPQDI>2.0.CO;2 Article history received: 10 Nov 1999 rev-recd: 19 Jun 2000 accepted: 30 Jun 2000 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Randel Tom Cox, Roy B. Van Arsdale, James B. Harris; Identification of possible Quaternary deformation in the northeastern Mississippi Embayment using quantitative geomorphic analysis of drainage-basin asymmetry. GSA Bulletin 2001;; 113 (5): 615–624. doi: https://doi.org/10.1130/0016-7606(2001)113<0615:IOPQDI>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract To investigate neotectonism in the Mississippi Embayment east of the New Madrid seismic zone, we identified geomorphic domains that show evidence of ground tilting during Quaternary time. Transverse basin profiles were converted to two-dimensional vectors that denote channel position with respect to basin divides. These basin-asymmetry vectors record the net direction and degree of lateral migration of trunk streams. More than 2500 vectors were measured and spatially averaged within 400 km2 bins. This field of 300 mean vectors delineates several domains that show preferred directions of stream migrations possibly driven by ground tilting. The timing of stream migration was interpreted using across-valley distributions of Quaternary alluvial terraces.Comparison of our mean vector field with subsurface structures suggests that some domain boundaries may be related to reactivated faults. Late Quaternary activity is suggested for two northeast-striking faults of the southeastern Reelfoot Rift margin. We acquired two seismic profiles showing near-surface faulting beneath scarps that follow the domain boundary associated with one of these northeast-striking faults (Big Creek fault zone). Reelfoot thrust seismicity ends on the south against this fault, suggesting that the rift margin has dextral slip accommodating northeastward movement of the thrust hanging wall. Our vector field also suggests late Quaternary movement on the Reelfoot thrust and on two other northwest-striking faults, here termed the Hatchie River fault and the Wolf River fault. Several other weak domains may imply minor elements of neotectonism. Our results demonstrate that morphometric analysis of drainage-basin asymmetry can be an effective reconnaissance tool within neotectonic settings. You do not currently have access to this article.

Methods and applications of a geomorphological GIS: a case study in the Ordos region of China

An information system designed for geomorphology has been established employing GIS tools, statistics, fuzzy mathematics, digital image processing and finite element analysis. In addition, we have reorganized and proposed a series of quantitative geomorphic analysis modules (quantitative analysis, information compound, division and assessment, dynamic simulation and prediction), and developed new technology in computer-aided geomorphic mapping. Then, by the methods mentioned above, we have made a quantitative analysis in a case study and worked out a map series which consists of about 100 maps on morphotectonics in the Ordos region in China. This work contributes to the development of geomorphology, the theory and applications of GIS, and research on regional morphotectonics, which shows that a GIS-based approach to geomorphic modelling has distinct advantages over traditional methods.