Application of natural gamma ray spectrometry in analysis of Late Ordovician carbonate sequence stratigraphic analysis in middle Tarim Basin
Yang Xiao-fa1,2, Lin Chang-song1, Yang Hai-jun3, Peng Li1,2, Liu Jing-yan1, Xiao Tian-jun3, Tong Jian-yu1, Wang Hai-ping1, Li Huan-pu1
1. The School of Natural Resources,China University of Geosciences,Beijing City,100083,China;
2. Education Ministry Key Lab of Marine Reservoir Evolution and Oil&Gas Accumulating Mechanism,China University of Geosciences,Beijing City,100083,China;
3. Tarim Branch Company of PetroChina,Korla City,Xinjiang Autonomous Region,841000,China
Abstract：Late Ordovician Tarim area is an edging carbonate platform.Based on natural gamma spectral logging data and the principle of sequence stratigraphy,the sedimentary sequences in Late Ordovician,the system tract and the change trends for sea-level lifting and drop have been studied.A second-order sequence,3 third sequences and 5 fourth sequences were identified in Late Ordovician Shiliang Lianglitage formation,meantime the sea level change curve in Late Ordovician was generated.The highstand system track and the transgressive system tract were developed in the O3l1 sequence and the O3l2 sequence,no record shows lowstand system tract,the transgressive system tract was only developed in O3l3,called transgressive sequence.The sediment record's response relation indicates that the evolution of the Late Ordovician platform in Central Tarim Basin Uplift was a flooding event.The reef-bank complex which is the favorable reservoir facies is mainly located in the lower part of the transgressive system tract and in the upper part of the highstand system track,while the source rocks in the sequence framework shows a significant heterogeneity,mainly distributing in transgressive system tract.The high values of the Thorium and potassium in the moving average curve and high-values of the source rock's total organic carbon amount show a good corresponding relationship,so the distribution location of the source rock in sequence framework can be quickly and completely identified.
阳孝法, 林畅松, 杨海军, 彭莉, 刘景彦, 肖天君, 佟建宇, 王海平, 李换浦. 自然伽马能谱在塔中地区晚奥陶世碳酸盐岩层序地层分析中的应用[J]. 石油地球物理勘探, 2010, 45(3): 384-391.
Yang Xiao-fa, Lin Chang-song, Yang Hai-jun, Peng Li, Liu Jing-yan, Xiao Tian-jun, Tong Jian-yu, Wang Hai-ping, Li Huan-pu. Application of natural gamma ray spectrometry in analysis of Late Ordovician carbonate sequence stratigraphic analysis in middle Tarim Basin. OGP, 2010, 45(3): 384-391.
