000 02343nab a2200229 4500
005 20260520000321.0
008 260224s2016 xxu ing
041 _aInglés
245 0 0 _aA new method for estimating total organic carbon content from well logs
260 _a
_b
_cago. 2016
270 _a31/08/2016 ; 31/08/2016
300 _a16 p. ; 1311-1327
520 _aTranscripción del resumen del autor: With the booming exploration and development of unconventional hydrocarbon resources in source rocks, the estimation of total organic carbon (TOC) content from well logs has become increasingly important because of the significance of TOC in the formation evaluation of those resources. In this paper, a new log overlay method is developed to estimate the TOC content of source rocks with excess radioactivity, but containing little or no potassium feldspar. Specifically, on the basis of previous results of log responses of source rocks, it is believed that the natural gamma ray (GR) log responses of source rocks in the applicable conditions are predominantly contributed by clay minerals and organic matter. A practical clay indicator is established to reflect the clay content using density and neutron logs. The indicator is effective not only in nonsource rocks that contain oil or water but also in source rocks. Furthermore, a new method was developed by overlaying the properly scaled clay indicator curve on the GR curve. In nonsource rocks, including clay-rich rocks and reservoirs saturated with oil or water, the two curves overlie each other, whereas a separation between the curves occurs in organic-rich source rocks. The separation between the curves was defined and expressed and can be used to calculate the TOC consecutively after careful calibration with core data. This method has been successfully applied to two shale gas plays with high-maturity kerogen in the Sichuan Basin, China. In addition, a source rock with low-maturity kerogen was used to verify the new method for its effectiveness, reliability, and widespread adaptability.
581 _a8
773 0 _tAAPG Bulletin
_g100
942 _cARTICULO
100 1 _aZhao, Peiqiang
_955632
100 1 _aMao, Zhiqiang
_955633
100 1 _aHuang, Zhenhua
_955634
100 1 _aZhang, Chong
_955635
999 _c189726
_d189726