Petrogenesis

The main questions concerning the volcanics of the IAP relate to the origin of the kamafugitic lavas at San Venanzo and Cupaello and the nature of carbonate-rich pyroclastic rocks present in several centres. Both issues have been much discussed in the literature, although the debate often has been based on preconceptions rather than on factual evidence. 

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Within the VGO saturates, distribution of paraffins, isoparaffins, and naphthenes is highly dependent on the petroleum source. The naphthenes account for roughly 60% of the saturates in a normal cmde oil. However, samples can be found having paraffins from <20 to >80%. In most samples, the / -paraffins from C2Q—are still present in sufficient quantity to be detected as distinct peaks in gc analyses. Some cmde oils show a nearly symmetric pattern of peaks such that each carbon number is present in regular progression up to a maximum around C -j. Other cmde oils show a similar distribution, but have preference for odd-numbered alkanes. Both the distribution and the selectivity toward odd-numbered hydrocarbons are considered to reflect differences in petrogenesis of the cmde oils. Although / -paraffins are distinct in the gc, these usually account for only a few percent of the saturates measured by gc. 

Green TH (1994) Experimental studies of trace element partitioning applicable to igneous petrogenesis-Sedona 16 years later. Chem Geol 117 1-36... 

Newman S, Macdougall JD, Finkel RC (1986) Petrogenesis and °Th- U disequilibrium at Mt. Shasta, Califonua, and in the Cascades. Contrib Mineral Petrol 93 195-206 Nichols GT, Wylhe PJ Stem CR (1994) Subduction zone melting of pelagic sediments constrained by melting experiments. Nature 371 785-788... 

Pearce JA, Parkinson IJ (1993) Trace element models for mantle melting application to volcanic arc petrogenesis. J Geol Soc Lond 76 373-403... 

Th disequilibria, magma petrogenesis and flux rates beneath the depleted Tonga-Kermadec island arc. Geochim Cosmochim Acta 61 4855-4884... 

The petrogenesis of the Ulsan carbonate rocks from the southeastern... 

Re-evaluating the origin of the Ulsan carbonates can be very important in understanding the geology and petrogenesis in the Mesozoic Kyongsang Basin, South Korea. This present work is summarized and reviewed from the Yang et al. (2003). 

Yang, K., Hwang, J. Yun, S. 2003. The petrogenesis of the Ulsan carbonate rocks from the southeastern Kyongsang Basin, South Korea. The Island Arc, 12, 428-439. 

Petrogenesis of basalts from the FAMOUS area Mid-Atlantic Ridge. Earth Planet. Sci. Letters, 36, 133-56. 

The interest in mineral-promoted organic reactions stems from the need to understand the fate of pesticides in soils and pollutants in sedimentary environments (8), petrogenesis (20-27), humification (19, 28, 29), the origin and evolution of life (1, 30), the use of clays as catalysts in industrial processes (31-37), in pharmaceutical applications (3), and as pigments and fillers in paper, plastic, and rubber (37). 

Gast PW, Huhhard NJ, Wiesmann H (1970) Chemical composition and petrogenesis of basalts from Tranquility Base. Geochim Cosmochim Acta Suppl 1 1143-1163... 

Stolper E, Newman S (1994) The role of water in the petrogenesis of Mariana trough magmas.Earth Planet Sci Lett 121 293-325... 

Recent appraisals of the state of art in experimental trace partitioning studies relevant to igneous petrogenesis may be found in the review articles of Green (1994) and Jones (1995). 

Ca = 0.000031, and Ca = 0.001824. The high relative abundance of °Ca (a result of its mass number A, which is a multiple of 4 and thus exceptionally stable cf section 11.3) is one of the two main problems encountered in this sort of dating (in Ca-rich samples, the relative enrichment in °Ca resulting from °K decay is low with respect to bulk abundance). The other problem is isotopic fractionation of calcium during petrogenesis (and also during analysis see for this purpose Russell et al., 1978). These two problems prevent extensive application of the K-Ca method, which requires extreme analytical precision. The isochron equation involves normalization to the Ca abundance... 

Holgate N. (1954). The role of liquid immiscibility in igneous petrogenesis. J. Geol, 62 439-306. 

McKay G. A. and Weill D. F. (1976). Petrogenesis of KREEP Proc. Seventh Lunar Scl Conf, 2427-2447. 

Ottonello G., Piccardo G. B. and Ernst W. G. (1979). Petrogenesis of some Ligurian peridotites, II Rare earth element chemistry. Geochim. Cosmochim. Acta, 43 1273-1284. 

Schreiber H. D. (1976). The experimental determination of redox states, properties, and distribution of Chromium in synthetic silicate phases and application to basalt petrogenesis. Ph.D. diss., University of Wisconsin. 

Petrogenesis of dykes related to Cu-Au base-metal Au-Ag occurrences, Mt. Freegold area, Dawson Range, Yukon Territory,... 

Ramezani, J. Tucker R.D. 2003. The Saghand region. Central Iran U-Pb geochronology, petrogenesis and implications for Gondwana tectonics. American Journal of Science, 303, 622-665. 

Whalen, J.B., Currie, K.L., Chappell, B.W. 1987. A-type granites geochemical characteristics, discrimination and petrogenesis. Contributions to Mineralogy and Petrology, 95, 407-419. 

Yang, X.M. Le Bas, M.J. 2004. Chemical composition of carbonate minerals from Bayan Obo, Inner Mongolia, China, implications for petrogenesis. Lithos, 72, 97-116. 

White, A.F., Schulz, M.S., Lowenstern, J.B., ViviT, D.V., Bullen, T.D. 2005. The ubiquitous nature of accessory calcite in granitoid rocks Implications for petrogenesis. Geochimica et Cosmochimica Acta, 69, 1455-1471. 

Eccles, D.R., Heaman, L.M., Luth, R.W., Creaser, R.A. 2004. Petrogenesis of the Late Cretaceous northern Alberta kimberlite province. Lithos, 77, 435-459. 

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