Background/Overview: Most differentiated rocky worlds in our Solar System have mantles of olivine, pyroxene, spinel, and calcic plagioclase (or equivalent high-pressure phase assemblages). Earth’s mantle peridotite and similar rocks in other silicate planets and asteroids normally melt to form basaltic magma, komatiite, or other olivinenormative melts. Details of planetary mantle compositions a...

Previous reports of reticulated filaments, an unknown microbe, document that they are ubiquitous in subsurface environments, including limestone caves, lava tubes, and even granite tunnels. Although initial reports of fossil reticulated filaments described preserved organic matter, additional instances involve replacement by calcite, Mn-oxides, silica, or copper silicates. We report on living r...

Gold has been found in the Cyprus-type volcanogenic massive sulfide ore (VMS) deposits of Corchia ophiolite (Parma province, Italy) in the Cantiere Donnini, Speranza and Pozzo mining sites. At Cantiere Donnini and Speranza, the mineralization occurs at the contact between pillow lava and sedimentary rocks. The Pozzo mineralization is hosted by a serpentinite. Concentrations of gold up to 3070 p...

twenty four samples of xenoliths and country rocks from the 1961 lava flow of calbuco volcano have been studied. fourteen samples have been analyzed for major elements and p, ni, ba, cr, v, zr, sc, y, and sr. five of these samples were further analyzed for sm, nd, sr, and pb isotope ratios. seventeen samples were analyzed under the microscope and three samples were analyzed by microprobe for th...

the kahnuj ophiolitic complex, a part of the jazmurian ophiolitic belt, is located on the western boundary of the jazmurian depression and is bounded by two major fault systems. there is a well-preserved, ophiolite pseudostratigraphy of early cretaceous to early palaeocene age and has a bearing on the mesozoic development of southeastern part of iran and adjacent region. the kahnuj ophiolitic c...

The Hezar Igneous Complex (HIC) in the south-eastern part of Urumieh-Dokhtar magmatic arc, is the most prominent magmatic feature in the Kerman Porphyry Copper Belt, that understanding magmatic evolution of which may shed light on the tectonomagmatic development of this less-studied part of an important magmatic arc in the Neotethys realm. The HIC has been developed in the the intersection of t...

the arghash area is located 45 km to southwest of neyshabour. the subvolcanic rocks in the area consist of biotite hornblende quartz monzodiorite porphyry, hornblende biotite quartz monzodiorite porphyry, hornblende monzonite porphyry, biotite hornblende monzonite porphyry, monzodiorite porphyry and biotite quartz monzodiorite porphyry units. the volcanic rocks consist of hornblende biotite dac...

The most important examples of magmatic ore deposits in volcanic rocks are Fe-Ni-Cu-(PGE) sulphides associated with Archean and Proterozoic komatiitic lava channels (Lesher, 1989). Komatiitehosted ores contain ~25% of the world’s nickel sulphide resource (≥ 0.8% Ni), including significant amounts of copper and platinum group elements (Ross and Travis, 1981). Field, experimental, and theoretical...

The Moon is generally thought to be geologically inactive, except for being pummeled by meteoroids of various sizes. The youngest returned igneous rocks are about 3 billion years old, although crater counting suggest some lava flows as young as a billion years. However, Peter Schultz (Brown University), Matthew Staid (Planetary Sciences Institute, Tucson), and Carlé Pieters (Brown University) r...