Abstract：Ichnology provides a basis for identification and analysis of depositional environment. Taking the Lower Cretaceous McMurray Formation,Mackay Ⅲ oil sands,Canada as an example,the sedimentary environments of the reservoir were studied with respect to trace fossils' species,size,associations,and facies indicators by high-resolution core photos and CT data. Results indicate that there are 12 species of ten genera in the Middle and Upper McMurray Formation,including Asterosoma isp.,Chondrites isp.,Diplocraterion isp.,Ophiomorpha nodosa,Palaeophycus tubularis,Planolites beverleyensis,Planolites isp.,Rosselia isp.,Skolithos verticalis,Skolithos isp.,Teichichnus isp.,and Thalassinoides isp.. According to the features of these fossils and surrounding lithology,three combinations, including Ophiomorpha-Skolithos,Asterosoma-Chondrites-Rosselia and Teichichnus-Rosselia-Thalassinoides, are established,representing intertidal,subtidal and shallow-marine environments respectively. Sand bodies in reservoir were deposited in the intertidal setting,being the main accumulation of hydrocarbon. This study not only reflects the superiority of CT data,but also provides a reference for recognizing the tidal flat environments.
Chen Hao,Huang Ji-Xin,Chang Guang-Fa et al. Ichnology identification and sedimentary enviorment analysis based on CT scanning: A case study from Mackay Ⅲ oil sands,Canada[J]. JOPC, 2018, 20(4): 703-712.
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