Microbial corrosion textures in volcanic glass from Cenozoic seafloor basalts and the corresponding titanite replacement microtextures in metamorphosed Paleoarchean pillow lavas have been interpreted as evidence for a deep biosphere dating back in time through the earliest periods of preserved life on earth. This interpretation has been recently challenged for Paleoarchean titanite replacement ...

taposed along the north-trending, high-angle Nahlin fault; all three tectonic elements are intruded by the Late Cretaceous Atlin Mountain pluton (Figure 1-19-2). The oldest rocks in the eastern domain are Mississippian to Triassic oceanic; crustal and sedimentary rocks of the Cache Creek Complex. These include ultramafite, basalt, limestone, chert, argillite and wacke, and probably a mixed ultr...

[1] These first measurements of specific surface area (SSA) of bulk samples of subsurfacemarine basalts were undertaken to determine the potential area available for microbial colonization. SSA ranged from 0.3 to 52 m/g of basalt with the lowest value coming from pillow basalt and the highest value from breccia. The average for massive and pillow basalts combined was 2.3 m/g. The total specific...

pillow lavas are locally conspicuous. A unit consisting of dark, thinly bedded sandstone and siltstone, lccally ranging to several hundred feet thick, is lowermost in the exposed section. The middle division consists of about 3,500 feet of mixed andesi.:e and basalt volcaniclastic rocks ~ lahar, tuff breccia, volcanic sandstone, and conglomeratic beds which rest on relatively thin, fossiliferou...

O are claimed to be pieces of ocean crust and upper mantle that have been thrust up onto continental crust and are now found in mountains, mainly along continental margins.1,2 An ideal ophiolite suite consists from bottom to top of peridotite, gabbro, sheeted dikes, basalt with pillow lavas and sedimentary rocks. The peridotite is considered to be an upper mantle rock, while the remainder of th...

pillow basalts, belonging to late cretaceous yüksekova complex are extensivelly exposed around elazıg in eastern turkey. this unit is a part of southeastern anatolian ophiolite belt and the southern branch of the neotethys. it represents the products of intra- oceanic subduction volcanism and mainly comprises pillow lavas, dykes and associated with sedimentary rocks. pillow lavas and feeder dyk...

Metal-oxidizing bacteria may play a key role in the submarine weathering of volcanic rocks and the formation of ferromanganese crusts. Putative fossil microbes encrusted in Mn oxide phases are commonly observed on volcanic glasses recovered from the deep ocean; however, no known Mn(II)-oxidizing bacteria have been directly identified or cultured from natural weathered basalts. To isolate epilit...

Pahoehoe lava flows are common in every basaltic province, and their submarine variants, pillow lavas and sheet flows, cover the bulk of the Earth. Pahoehoe flows are emplaced by inflation—the injection of molten lava underneath a solidified crust. Only in the past few years has an understanding of the inflation process and the ability to recognize ancient inflated lava flows been achieved. All...

the nain and ashin ophiolites are located in northeastern isfahan province, in western central-east iranian microplate. pillow lavas are one of the most significant cretaceous rock units. the lower partial melting degree in mantle peridotites of ashin ophiolite, and the derived melt by melting their clinopyroxene caused a more basic (basalt) and enriched nature for the ashin pillow lavas, where...