This study focusses on bleaching phenomena the pore scale in an Olenekian (Upper Buntsandstein) sandstone quarry. The area exposes a 10 m thick red body with up to cm-sized, greyish-white laminae sandstones. Analyses focus bleached and unbleached zones same cm-sized samples. Bleached show larger grain size (by 27 μm), less compaction higher porosity 3 %). They also exhibit stronger cementation ...

Low Vp/Vs anomalies can assist in prospect identification in tight gas sandstone reservoirs, because they are related to good quality rocks (sandstones with low clay content), presence of gas, and overpressure conditions. In such rocks, gas saturation lowers Vp/Vs and the effect is larger if the gas is overpressured. On the other hand, with water saturation, Vp/Vs increases and the effect is en...

the sorkheh deposit in northwestern iran exhibits several readily visible general characteristics of sediment-hosted stratiform copper (ssc) mineralization. it consists of fine-grained disseminated base-metal sulfides within gray sandstones (gray beds, the basal whitish miocene sandstone and shallow-water) that overlie a thick sequence of red beds (miocene upper red formation). the host gray be...

Abstract The Moeda Formation (Caraca Group, base of Minas Supergroup) registers the initial rift stages Basin in Quadrilatero Ferrifero, Southern Sao Francisco craton, SE-Brazil. We present stratigraphic and U-Pb detrital zircon dating analyses that contribute to comprehension its sedimentary evolution southernmost Gandarela Ouro Fino synclines (Central-Eastern Ferrifero). sequence consists a b...

A multi-proxy provenance study of Late Carboniferous to Middle Jurassic sandstones from the eastern Sverdrup Basin was undertaken employing optical petrography and heavy mineral analysis, chemical analysis apatite, garnet rutile grains, as well detrital zircon U–Pb geochronology Hf isotope analysis. strata on southern basin margin are inferred being predominantly reworked Silurian Devonian with...

Lower Cretaceous (Aptian-Albian) sandstones of the Ghaggar-Hakra Formation in Barmer Basin northwest Rajasthan, India, have a complex depositional history which is confusing given they are quartzose arenites. The heavy mineral grains very well-rounded, and assemblage dominated by zircon rutile suggesting that sediments been recycled multiple times, whilst presence staurolite indicates metapelit...

Abstract The Tianshan Range–Junggar Basin– Kalamaili Range system represents the southwestern Central Asian Orogenic Belt and is a natural laboratory for studying intracontinental deformation processes. Its current topography product of farfield effects Cenozoic India-Asia collision. However, Mesozoic topographic tectonic evolution Ranges their impacts on Junggar Basin remain enigmatic due to s...

Abstract Ophiolitic mélanges in Anatolia represent Mesozoic subduction-accretion complexes, which are unusually poor land-derived coarse-clastic rocks. A segment of the ophiolitic mélange Beynam region south Ankara was studied. The consists three accretionary units (AUs), distinguished by lithology, structure, age and geochemistry. At base there is a serpentinite mélange, overlain semi-intact U...

The present-day structure of the Eastern Cordillera in NW Argentina is governed by structural and lithological heterogeneities inherited from preceding deformation phases, which influence localization newly-formed faults inversion pre-existing structures. Salta Rift Basin formed during a Late Jurassic-Cretaceous extensional phase created dominant stratigraphic imprint that particularly evident ...