000			02609nab a2200241 4500
005			20260520000320.0
008			260224s2016 xxu ing
041			_aInglés
245	0	0	_aChemometric recognition of genetically distinct oil families in the Los Angeles basin, California
260			_a _b _cene. 2016
270			_a03/03/2016 ; 03/03/2016
300			_a20 p. ; 115-135
520			_aTranscripción del resumen del autor: The prolific Los Angeles basin in California may be the most petroliferous province on Earth per volume of sedimentary fill. However, because most exploration in the basin occurred prior to the advent of modern geochemical methods, genetic relationships among the various petroleum accumulations and their source rocks have remained speculative. A training set of 24 source-related biomarker and stable carbon isotope ratios for 111 non- or mildly biodegraded oil samples from the basin was used to construct a chemometric (multivariate statistics) decision tree. The decision tree allows genetic classification of additional oil or source-rock extract samples that might be collected. The decision tree identifies 6 tribes and a total of 12 genetically distinct oil families. The families have different bulk properties, such as API gravity and sulfur content, which were previously explained as resulting from secondary processes, including thermal maturity or biodegradation. However, the chemometric assignments are based on genetic properties that reflect distinct organofacies. The oil families occur in different locations and reservoir intervals in the basin, consistent with their origins from different organofacies of active source rock. The source-rock depositional environment for each oil family can be inferred using biomarker and isotope ratios. The samples show stable carbon isotope ratios for saturate and aromatic hydrocarbons that indicate different organofacies of Miocene marine source rocks. Tribes 1 and 2 straddle the central trough, mainly occur east of the Newport-Inglewood fault zone (NIFZ), and show evidence of proximal, clay-rich source rock deposited under suboxic conditions with elevated angiosperm input. Tribes 3–6 occur west of the NIFZ and show evidence of more distal, clay-poor source rock deposited under anoxic conditions.
581			_a1
773	0		_tAAPG Bulletin _g100
942			_cARTICULO
100	1		_aPeters, K.E. _948089
100	1		_aWright, T.L. _955216
100	1		_aRamos, L.S. _955217
100	1		_aZumberge, J.E. _955218
100	1		_aMagoon, L.B. _948090
999			_c189471 _d189471