Abstract Eclogite-facies mineral assemblages are commonly preserved in mafic protoliths within continental terranes. It is widely accepted that the entirety of these terrains must also have been subducted to eclogite-facies conditions. However, evidence felsic material transformed at conditions lacking. Low-strain metagranites ultrahigh-pressure metamorphic Tso Morari Complex Ladakh, Himalaya, ...

Propylene and acetylene are released to mine air with the increase in the temperature of self-heating coal. Concentrations of these gases in mine air are applied as indicators of the progress of the self-heating process. Hydrocarbons emitted from the self-ignition center are sorbed on coal, while migrating through the mine workings. Coal crushed during the mining process is characterized by a h...

High- and ultrahigh-pressure rocks occur in the Austroalpine Nappes a ~400 km long belt from Texel Complex west to Sieggraben Unit east. Garnet growth during pressure increase was dated using Lu-Hf chronometry. The results range between c. 100 90 Ma, indicating short-lived period of subduction. Combined with already published data, our estimates metamorphic conditions indicate field gradient in...

Introduction: Peak broadening recognized in X-ray diffraction (XRD) and micro-Raman (MRS) spectra of experimentally and naturally shock-metamorphosed carbonates from carbonate-target bo-lide impact structures has been shown to be a reliable indicator of impact-related shock-metamorphism [1-7]. However, studies have not yet shown whether this peak broadening is unique to or diagnostic of all car...

The protoliths of metamorphosed argillaceous rocks from the Garmichay area in the East Azerbaijan province of NW Iran were clay-rich sediments of reworked nature, originating most likely from an andesite to andesite-basalt source and deposited in an active continental margin tectonic setting. The protoliths of the Garmichay metapelites experienced low to moderate chemical weathering. Andalusite...

Intrusion of the Kalaybar nepheline syenite into the Cretaceous pelitic and calcareous sediments has produced a thermal aureole up to 1km thick. Six mineralogical zones are developed in the pelitic rocks with minerals such as cordierite, K feldspar, sillimanite and corundum. Chemically suitable rocks are partially melted in response to the heat from the pluton. Five mineralogical zones are deve...

Seven eclogite facies samples from lithologically different units which structurally underlie the Semail ophiolite were dated by the Ar/Ar and Rb–Sr methods. Despite extensive efforts, phengite dated by the Ar/Ar method yielded saddle, hump or irregularly shaped spectra with uninterpretable isochrons. The total gas ages for the phengite ranged from 136 to 85 Ma. Clinopyroxene–phengite, epidote–...