17 resultados para modern rock
Resumo:
Microbial ichnofossils in volcanic rocks provide a significant record of subsurface microbes and potentially extraterrestrial biosignatures. Here, the textures, mineralogy, and geochemistry of two continental basaltic hydrovolcanic deposits - Reed Rocks and Black Hills - in the Fort Rock Volcanic Field (FRVF) are investigated. Methods include petrographic microscopy, micro and powder X-ray diffraction, SEM/BSE/EDF imaging, energy dispersive spectroscopy, stable isotopes, and X-ray fluorescence. Petrographic analysis revealed granular and tubular textures with biogenic morphologies that include terminal enlargements, septate divisions, branching forms, spiral filaments, and ovoid bodies resembling endolithic microborings described in ocean basalts. They display evidence of behaviour and a geologic context expressing their relative age and syngenicity. Differences in abiotic alteration and the abundance/morphotype assemblage of putative microborings between the sites indicate that water/rock ratio, fluid composition and flux, temperature and secondary phase formation are influences on microboring formation. This study is the first report of reputed endolithic microborings in basalts erupted in a continental lacustrine setting.
Resumo:
Indenture of deed of bargain and sale between Samuel Rock of Crowland Township and Samuel Street of the Town of Niagara for 1 acre in Lot no. 179 in the Town of Niagara – instrument no. 13070. A memorial of this record was made on Feb. 21, 1856, List B, Folio 169. An envelope addressed to Joseph Woodruff, Clerk of the Peace and postmarked Jan. 1857 was included with this document, July 17, 1840.