Ice sheet surface lineaments as nonconventional indicators of East Antarctica bedrock tectonics

Abstract

A recent focus of major international\ud exploration in East Antarctica has been\ud aimed at revealing its bedrock topography\ud and imaging its tectonic architecture and evolution.\ud Here we present the tectonic interpretation\ud of regional-scale lineaments revealed\ud by the Radarsat mosaic of Antarctica on\ud the ice sheet surface in the Vostok–Dome C–\ud Adventure Basin region. These lineaments\ud appear in the radar backscatter textures as\ud alignments of marked tonal variations with\ud lengths of tens to hundreds of kilometers and\ud were identifi ed using an automated methodology.\ud We explore the origin scenarios for the\ud ice sheet surface lineaments by comparing\ud their azimuthal trends and spatial distribution\ud with the main morphotectonic features\ud of the bedrock. Azimuthal analysis reveals\ud that lineaments cluster around two preferential\ud directions interpreted as structural or\ud tectonic domains. These show strong correlations\ud with azimuths of tectonic fabrics in the\ud bedrock. The main lineament domain parallels\ud the morphotectonic features of the study\ud area, namely the Adventure Basin and the\ud Concordia and Aurora Trenches. The second\ud lineament set corresponds to the mean\ud orientation of the Lake Vostok depression.\ud The spatial analyses of the two lineament\ud domains strengthen our fi ndings and interpretations.\ud Comparisons with wind and ice\ud fl ow directions exclude their infl uence on the\ud identifi ed lineament pattern. Results reveal\ud the tectonic origin of the lineament domains,\ud and demonstrate the method’s usefulness as\ud a tool for tectonic studies of regions characterized\ud by thick covers. These regions include\ud other areas of the East Antarctic craton such\ud as the Gamburtsev Subglacial Mountains, as\ud well as deserts or surfaces of other planets

The Cenozoic fold-and-thrust belt of Eastern Sardinia: Evidences from the integration of field data with numerically balanced geological cross section

“…[], reverse faults and thrusts are associated to a Cenozoic Alpine‐related compressional tectonic event. The alternative model interprets these faults as secondary compressional structures related to strike‐slip tectonics (i.e., positive flower structures) [ Pasci , ; Pasci et al ., ; Oggiano et al ., ] as often observed along major strike‐slip corridors [e.g., Cianfarra and Salvini , , ].…”

Lineament domain analysis to infer groundwater flow paths: Clues from the Pale di San Martino fractured aquifer, Eastern Italian Alps

“…Following Cianfarra and Salvini (2014), the azi muthal scattering of lineaments indicated that the main lineament domain (N340°) is the least scattered among the three directions identified and thus is directly related to the youngest tectonic phase active in the area. Field surveys suggested a similar conclusion and confirm the tectonic evolution sequence already identified by previous authors (Bosellini and Doglioni, 1986;Doglioni, 1987;Castellarin et al, 1992).…”

“…The ratio between the normalized Gaussian height (NorH in the table of Fig. 4) and the SD of each Gaussian peak, NorH/SD, represents the peak's sharpness (Cianfarra and Salvini, 2014), that is, the near parallelism among lineaments belonging to the same domain. The morphology of the earth sur face results from the competition between tectonics and erosional processes.…”

“…In this way, the NorH/SD parameter, indicat ing the azimuthal scattering of lineaments with respect to their frequency, can be used to evaluate the relative youth of the lineament domains. In particular, comparatively higher values of NorH/SD indicate relatively younger lineament domains (Salvini et al, 1979;Cianfarra and Salvini, 2014). The main N340° peak has the highest NorH/SD value of 8.94, compared to values of 7.21 and 5.38 for the N25° and N80° domains.…”

“…Other studies investigated the connectivity of lineaments (Shaban et al, 2006) and their length and density (Teeuw, 1995;Hung et al, 2004) as critical factors controlling the permeability of aquifers. Nevertheless, a direct relation between lineaments and tectoni cally controlled morphologies is still controversial because lineaments from synthetic scaled images do not relate directly to faults or tectonic discontinui Lucianetti et al | Lineament analysis to infer groundwater flow paths in fractured aquifers GEOSPHERE | Volume 13 | Number 5 ties (Goldscheider and Andreo, 2007;Cianfarra and Salvini, 2014). Previous studies have explored the relation between lineament domains and crustal stress in the various geodynamic environments (Mazzarini and Salvini, 1994;Mazzarini and D'Orazio, 2003;Pardo et al, 2009;Pischiutta et al, 2013;Gior dano et al, 2013;Cianfarra and Salvini, 2014, 2016b, but none of them focused on groundwater exploration.…”