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.
Fund:Co-funded by the National Science and Technology Major Project of China(No.2016ZX05031)and the National Natural Science Foundation of China(No.41472119)
About author: Chen Hao,born in 1991,is a Ph.D. candidate. He is engaged in research of development geology. E-mail: chen19613@petrochina.com.cn.
Cite this article:
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.
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.
[1] 范若颖,龚一鸣. 2017.21世纪遗迹学热点与前沿: 第 14届国际遗迹组构专题研讨会综述. 古地理学报, 19(5): 919-926. [Fan R Y,Gong Y M.2017. Focus and frontiers of ichnology in the 21st century: Outline of the 14th International Ichnofabric Workshop. Journal of Palaeogeography(Chinese Edition), 19(5): 919-926] [2] 刘亚明,谢寅符,张志伟,阳孝法,王丹丹. 2017. 西加拿大盆地 M 区块层序地层与油砂资源评价. 科学技术与工程,(10): 13-21. [Liu Y M,Xie Y F,Zhang Z W,Yang X F,Wang D D.2017. Sequence stratigraphy and evaluation of oil sands resources in Block M,Western Canada Basin. Science Technology and Engineering,(10): 13-21] [3] 王海邻,胡斌,宋慧波. 2017. 山东青岛和日照滨岸潮间带现代生物遗迹组成与分布特征. 古地理学报, 19(4): 663-676. [Wang H L,Hu B,Song H B.2017. Composition and distribution characteristics of modern biogenic traces in intertidal flat in Qingdao and Rizhao area,Shangdong Provinc. Journal of Palaeogeography(Chinese Edition), 19(4): 663-676] [4] 张立军,范若颖. 2016. 遗迹学的可持续发展: 第 4届国际遗迹学大会综述. 古地理学报, 18(5): 717-720. [Zhang L J,Fan R Y.2016. Biological traces towards sustainable development: Outline of the Fourth International Congress on Ichnology. Journal of Palaeogeography(Chinese Edition), 18(5): 717-720] [5] Bradshaw M A.2010. Devonian trace fossils of the Horlick Formation,Ohio Range,Antarctica: Systematic description and palaeoenvironmental interpretation. Ichnos, 17(2): 58-114. [6] Flach P D,Mossop G D.1985. Depositional environments of Lower Cretaceous McMurray Formation,Athabasca Oil Sands,Alberta. AAPG Bulletin, 69(8): 1195-1207. [7] Fustic M,Hubbard S M,Spencer R,Smith D G,Leckie D A,Bennett B,Larter S.2012. Recognition of down-valley translation in tidally influenced meandering fluvial deposits,Athabasca Oil Sands(Cretaceous),Alberta,Canada. Marine and Petroleum Geology, 29(1): 219-232. [8] Gerard J,Bromley R.2008. Ichnofabrics in clastic sediments: Applications to sedimentological core studies: A practical guide. Geochronique: Revue d'Information d'Expression Francaise en Sciences de la Terre, 110: 38-92. [9] Gingras M K,MacEachern J A,Dashtgard S E.2011. The potential of trace fossils as tidal indicators in bays and estuaries. Sedimentary Geology, 279: 97-106. [10] Gingras M K,Baniak G,Gordon J,Hovikoski J,Konhauser K O,Croix A L,Lemiski R,Mendoza C,Pemberton S G,Polo C,Zonneveld J P.2012. Porosity and permeability in bioturbated sediments. Trace fossils as indicators of sedimentary environments. Developments in Sedimentology, 64: 837-868. [11] Keighley D G,Pickerill R K.1997. Systematic ichnology of the Mabou and Cumberland groups(Carboniferous)of western Cape Breton Island,eastern Canada, 1: Burrows,pits,trails,and coprolites. Atlantic Geology, 33(3): 181-215. [12] Knaust D,Warchol M,Kane I A.2014. Ichnodiversity and ichnoabundance: Revealing depositional trends in a confined turbidite system. Sedimentology, 61(7): 2218-2267. [13] Hofmann R,Buatois L A,MacNaughton R B,Mangano M G.2015. Loss of the sedimentary mixed layer as a result of the end-Permian extinction. Palaeogeography,Palaeoclimatology,Palaeoecology, 428: 1-11. [14] Labrecque P A,Hubbard S M,Jensen J L,Hubbard S M,Nielsen H.2011. Sedimentology and stratigraphic architecture of a point bar deposit,Lower Cretaceous McMurray Formation,Alberta,Canada. Bulletin of Canadian Petroleum Geology, 59(2): 147-171. [15] McCrossan R G,Porter J W.1973. The geology and petroleum potential of the Canadian sedimentary basins: A synthesis. CSPG Special Publications,Memoir 1: 589-720. [16] Mukhametshina A,Hascakir B.2014. Bitumen extraction by expanding solvent-steam assisted gravity drainage(ES-SAGD)with asphaltene solvents and non-solvents. In: SPE Heavy Oil Conference-Canada. Society of Petroleum Engineers,2014. [17] Musial G,Reynaud J Y,Gingras M K,Fenies H,Labourdette R,Parize O.2012. Subsurface and outcrop characterization of large tidally influenced point bars of the Cretaceous McMurray Formation(Alberta,Canada). Sedimentary Geology, 279: 156-172. [18] Nara M.1995. Rosselia socialis: A dwelling structure of a probable terebellid polychaete. Lethaia, 28(2): 171-178. [19] Pemberton S G.1998. Ichnology Atlas. University of Alberta at Edmonton and University of Colorado at Boulder,electronic source. Ichnology Research Group(IRG): 1-34. [20] Pemberton S G,Frey R W.1982. Trace fossil nomenclature and the Planolites-Palaeophycus dilemma. Journal of Paleontology, 56(4): 843-881. [21] Pemberton S G,Gingras M K.2005. Classification and characterizations of biogenically enhanced permeability. AAPG Bulletin, 89(11): 1493-1517. [22] Schlirf M.2003. Palaeoecologic significance of Late Jurassic trace fossils from the Boulonnais,N France. Acta Geologica Polonica, 53(2): 123-142. [23] Uchman A,Caruso C,Sonnino M.2012. Taxonomic review of Chondrites affinis(Sternberg,1833)from Cretaceous-Neogene offshore-deep-sea Tethyan sediments and recommendation for its further use. Rivista Italiana di Paleontologia e Stratigrafia(Research in Paleontology and Stratigraphy), 118(2): 313-324.