油气勘探作业中往往要求做到即发现即解释,对随钻储层解释评价的要求越来越高。为了提高珠江口盆地恩平凹陷韩江组浅层低阻油层的随钻解释评价精度,探索了利用录井资料进行浅层低阻油层随钻识别及评价的方法:从岩性及沉积环境因素、构...油气勘探作业中往往要求做到即发现即解释,对随钻储层解释评价的要求越来越高。为了提高珠江口盆地恩平凹陷韩江组浅层低阻油层的随钻解释评价精度,探索了利用录井资料进行浅层低阻油层随钻识别及评价的方法:从岩性及沉积环境因素、构造因素和工程因素3个方面系统分析了韩江组浅层低阻油层的成因;针对韩江组浅层疏松、砂泥岩薄互层、荧光显示低和气体比低的特点,利用三维定量荧光、FLAIR(fluid logging&analysis in real time,实时地层流体录井)及岩石热解色谱等录井新技术,对研究区典型浅层低阻油层进行了识别和评价。评价结果与取样结论一致,对提高研究区勘探效益有一定帮助。展开更多
We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depressio...We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depression, Tibet. Coupled with previously published data in the region, this paper proposes new insights into the geochronological framework for the Nadigangri Formation. The deposition ages of tuffite from top to bottom in the Woruo Mountain, Quem Co and Dongqu River, are 203 Ma, 226 Ma, 221.5 Ma and 221.1 Ma, respectively. The detrital zircons yield a younger cluster of ages of 201.5-225 Ma from the conglomerate of the Quem Co Formation. The Late Triassic Nadigangri Formation defines a temporal range approximately between 201 and 225 Ma （Norian-Rhaetian）, including three predominant groups of 220-225 Ma, 210-217 Ma and 201-205 Ma, which correspond with the three main rifting episodes of initial rifting, further rifting and final rifting. Positive ~Hf（t） value and low model ages in younger detrital zircons suggests a juvenile character. However, the Hf isotopes of magmatic zircons display the presence of reworked ancient crust with 1.1-1.8 Ga. These results provide strong constraints not only on the temporal range of the Late Triassic Nadigangri Formation, but also on the onset of the Qiangtang Mesozoic rift basin.展开更多
文摘油气勘探作业中往往要求做到即发现即解释,对随钻储层解释评价的要求越来越高。为了提高珠江口盆地恩平凹陷韩江组浅层低阻油层的随钻解释评价精度,探索了利用录井资料进行浅层低阻油层随钻识别及评价的方法:从岩性及沉积环境因素、构造因素和工程因素3个方面系统分析了韩江组浅层低阻油层的成因;针对韩江组浅层疏松、砂泥岩薄互层、荧光显示低和气体比低的特点,利用三维定量荧光、FLAIR(fluid logging&analysis in real time,实时地层流体录井)及岩石热解色谱等录井新技术,对研究区典型浅层低阻油层进行了识别和评价。评价结果与取样结论一致,对提高研究区勘探效益有一定帮助。
基金funded by the National Natural Science Foundation of China(Grant No.41502112 and 41702119)a project program under China Geological Survey(No.DD20160159)
文摘We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depression, Tibet. Coupled with previously published data in the region, this paper proposes new insights into the geochronological framework for the Nadigangri Formation. The deposition ages of tuffite from top to bottom in the Woruo Mountain, Quem Co and Dongqu River, are 203 Ma, 226 Ma, 221.5 Ma and 221.1 Ma, respectively. The detrital zircons yield a younger cluster of ages of 201.5-225 Ma from the conglomerate of the Quem Co Formation. The Late Triassic Nadigangri Formation defines a temporal range approximately between 201 and 225 Ma （Norian-Rhaetian）, including three predominant groups of 220-225 Ma, 210-217 Ma and 201-205 Ma, which correspond with the three main rifting episodes of initial rifting, further rifting and final rifting. Positive ~Hf（t） value and low model ages in younger detrital zircons suggests a juvenile character. However, the Hf isotopes of magmatic zircons display the presence of reworked ancient crust with 1.1-1.8 Ga. These results provide strong constraints not only on the temporal range of the Late Triassic Nadigangri Formation, but also on the onset of the Qiangtang Mesozoic rift basin.
