[1] The earliest formed crust on a single plate planet such as Mars should be preserved, deeply buried under subsequent surface materials. Mars’ extensive cratering history would have fractured and disrupted the upper layers of this ancient crust. Large impacts occurring late in Martian geologic history would have excavated and exposed this deeply buried material. We report the compositional an...

the area under study is located 75 km north of isfahan north of fenshark village.the mesozoic deposits of this area have been metamorphosed in the vicinity of neogene granodiorites and quartzdiorites ,forming hornfelses in three individual facies albit-epidot-hornfelses in three individual facies albit-epidot-hornblende-and pyroxene hornfels. wollastonite,vesuvianite,garnet and calcite are the ...

We report the first systematic study of H2O speciation in dacitic melt with total dissolved H2O ranging from 1.4 to 2.6 wt%. Samples were heated in a one-atmosphere tube furnace at 480–590 °C for certain durations and then quenched in water or air. Species concentrations were measured with Fourier transform infrared (FTIR) spectroscopy. At a given temperature, the equilibrium constant for the r...

The physical and mechanical properties of the andesite forming much of the island of Gökçeada (Imbros), Turkey, were investigated using 54 mm samples cores from 12 blocks obtained from a quarry. The results were evaluated using regression analysis and good empirical relationships were obtained.

Introduction: Amphibole has been reported from a few groups of Martian meteorites (basaltic, lherzolitic and dunitic groups) [1-4]. They are always present within a magmatic inclusion trapped in pyroxene and olivine in spite of the large difference of the host petrology. Their mineral compositions are almost identical to one another and are kaersutitic. So far, only observations by optical micr...

Introduction: Near-infrared spectra of pyroxenes have distinct absorption features at approximately 1 and 2 µm. The positions of these features are dependent on the composition of the pyroxene [1,2]. Pyrox-ene spectra have been observed on the Martian surface [e.g., 3], and at high spectral resolution by the ISM imaging spectrometer [4] on board the Phobos-2 spacecraft in 1989. Previous researc...

New analytical and experimental data constrain the storage and equilibration conditions of the magmas erupted in 1912 from Novarupta in the 20th century’s largest volcanic event. Phase relations at H2O+CO2 fluid saturation were determined for an andesite (58.7 wt% SiO2) and a dacite (67.7 wt%) from the compositional extremes of intermediate magmas erupted. The phase assemblages, matrix melt com...