U-Pb and Ar/Ar dates from the Talladega belt, southernmost Appalachians, provide insight into the timing and nature of pre-Alleghanian tectonism in this region. Low-grade metasedimentary rocks of the Talladega belt represent the outermost preserved portions of the southern Laurentian margin, thus recording the earliest orogenic events that affected the margin, in addition to later overprinting ...

Infrared laser probe Ar/Ar geochronology, instrumental neutron activation analysis (INAA) and analytical electron microscopy have been performed on four 0.5 1.0 0.3 cm polished rock tiles of Apollo 16 and 17 granulitic breccias (60035, 77017, 78155, and 79215). Pyroxene thermometry indicates that these samples were re-equilibrated and underwent peak metamorphic sub-solidus recrystallization at ...

Major, minor, and trace element geochemistry as well iron oxidation state isotopes were investigated in serpentinites olivine-talc fels present along a metamorphic gradient the Bergell contact aureole (Central European Alps) to evaluate mobility during serpentine. This is an ideal target study dehydration of mantle rocks due increase temperature from greenschist facies conditions (350°C) amphib...

3 INTRODUCTION 4 Aim and approach 4 Structural domains in the Swedish part of the Baltic Shield defined by deformation zones and formline patterns 4 Age and character of high-T deformation zones in the Baltic Shield 6 GEOLOGY OF EAST CENTRAL SWEDEN 7 Rocks and ages 7 Metamorphism 8 Typical features of low pressure-high temperature metamorphism 9

northwest of shir-kuh batholith, a number of leucocratic granitic and granodioritic plutons have intruded sedimentary hosts including shale-sandstone (triassic-jurassic) and sandstone-conglomerate (lower cretaceous). contact metamorphism and hydrothermal alterations are widespread. late alteration assemblage mainly occurs in arkosic sandstones of sangestan formation and includes propylitic, qua...

The siliceous shale oil and gas in Nadanhada terrane has been studied through field geological survey, geochemistry sedimentary petrology. results show that the area belongs to a good reservoir, rock is brittle suitable for exploitation. abundance of organic matter relatively high. From west east from south north, increases maturity decreases. dynamic metamorphism thermal contact rocks are grad...

The diagenetic history of Triassic sandstone from the Beacon Supergroup, Victoria Land, Antarctica, can be divided into three main phases of shallow burial diagenesis, contact diagenesis (temperatures of 200-300oC), and post-contact diagenesis, on the basis of petrographic and geochemical analyses. Shallow burial diagenesis is characterised by minor compaction, K-feldspar alteration to illite, ...