Basins formation

Sulfur constitutes about 0.052 wt % of the earth s cmst. The forms in which it is ordinarily found include elemental or native sulfur in unconsohdated volcanic rocks, in anhydrite over salt-dome stmctures, and in bedded anhydrite or gypsum evaporate basin formations combined sulfur in metal sulfide ores and mineral sulfates hydrogen sulfide in natural gas organic sulfur compounds in petroleum and tar sands and a combination of both pyritic and organic sulfur compounds in coal (qv). 

These different sites of hydrothermal and ore-forming activity may have resulted from the mode of subduction of the Pacific Plate. Mariana-type subduction (characterized by a steep angle of subduction and back-arc basin formation Uyeda and Kanamori, 1979) during middle Miocene caused WNW-ESE extension, submarine hydrothermal activity, thick accumulation of bimodal (basaltic and dacitic) volcanic activity (Green tuff) and Kuroko-type formation (Shikazono and Shimizu, 1993). Plio-Pleistocene Chilean-type subduction (shallow-dipping subduction zone, E-W compression Uyeda and Kanamori, 1979) and oblique subduction of the Pacific Plate beneath the North American Plate led to uplift and expansion of land area, subaerial hydrothermal activity accompanied by meteoric water circulation, subaerial andesitic volcanic activity and formation of vein-type deposits. 

Fig. 3.4. Range chart of back-arc basin formation. Solid lines show confined age ranges of the formation of marginal basins by seafloor spreading, and broken lines show rough estimates of the age range. Rhombic marks show the timing of entrapment of the basins (Tamaki and Honza, 1991).

Kaufmann RS, Frape SK, McNutt R, Eastoe C (1993) Chlorine stable isotope dishibution of Michigan Basin formation waters. Applied Geochem 8 403-407... 

Schubel, J.R. (ed.) (1972) Classification according to mode of basin formation. In The Estuarine Environment Estuaries and Estuarine Sedimentation, pp. 2-8, American Geological Institute, Washington, DC. 

Dahymple G. B. and Ryder G. (1993) Ar/ Ar age spectra of Apollo 15 impact melt rocks by laser step heating and then-bearing on the history of lunar basin formation. J. Geophys. Res. 98, 13085-13095. 

Higgs, W.G. 1988. Syn-sedimentary structural controls on basin formation in the Gulf of Corinth, Greece. Basin Res., 1 155-165. 

Badley, M.E., Price, J.D., Rambech Dahl, C. Aodestein, T. (1988) The structural evolution of the northern Viking Graben and its bearing upon exten-sional models of basin formation. J. geol. Soc., Land., 145, 455-472. 

Tankard, A.J. Welsink, H.J. (1989) Mesozoic extension and styles of basin formation in Atlantic Ganada. In Extensional Tectonics and Stratigraphy of the North Adamic Ocean Margins (Eds Tankard, A.J. Balkwill, H.R.). Mem. Am. Ass. Petrol. Geol., Tulsa, 46, 175-195. 

Dissolved organic species have been known to exist in sedimentary basin formation waters since before the turn of the century (5.6.71. A host of aqueous organic species have been identified in sedimentary formation waters including hydrocarbons, mono-, di- and tri-carboxylic acid anions, keto and hydroxy-acids, amino acids, phenols, cresols, and hydroxybenzoic acids (8.9.10.11.121. 

So Mars may have experienced warm and cold climates episodically in its history. The reasons for climate changes on Mars can be manifold. Besides changes of the obliquity of its spin axis that certainly happened, other effects such as large volcanic eruptions, impacts of large meteorites and others have to be considered (see also Kargel and Strom, 1996 [178].) Climatic change on Mars caused by impact basin formation was studied by Matsui, Tajika, and Abe, 1988 [220]. 

Matsui, T, Tajika, E., Abe, Y. Climate and impact climatic change on mtirs caused by impact basin formation. In Lunar and Rlanetary Institute Conference Abstracts. Lunar and Rlanetary Inst., Technical Report, vol. 19, p. 742 (1988)... 

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