Study On Cambrian Lithofacies Palogeography In Luxi Block

Luxi block is situated west of Tanlu foult in the Shandong region,Cambrian formation is continuously and good,palaeophyte fossils are veryrich,the research level is high. With the appearance of the Four serices Ten stages of Cambrian, it is necessary to make a new division to Cambrian in Luxi Block,and draw up new lightfaces paleogeography map on the new frame.Luxi Cambrian rock formation include Liguan formation, Zhushadong formation, Mantou formation, Zhangxia formation, Gusahn formation, Chaomidian formation and Sanshanzi formation C section from bottom to top. It is a Sedimentary of epicontinental sea clasolite to carbonatite. The main lithology include: sandstone, glutenite, shale, microcrystalline limestone, grain limestone, microbialite, calcirudite and dolomite.According to the paleontology species and distribution of sequence in the section,the Cambrian formation include 21 trilobite biotic zone. Based on this consult and follow the international Cambrian four series program ,the Luxi block include three series and right stages:the second series(the third stage,the fourth stage),the third series(the fifth stage,Gushan stage,Guzhang stage), Furong series(Paibi stage,the ninth stage,the tenth stage).Many sedimentary facies were divided according to grainsize, sedimentary structures, texture, bed geometry and fossil contents.they are foreshore , dolomite flat, mud flat, sand flat, limestone flat, sand and mud flat, bank, interbank sea, lagoon, algal flat. Based on the depositional environment analyze, composed eight lithofacies paleogeographic maps,show that Luxi Block experiences the sedimentary cycle from transgression to regression, and establish the sedimentary model of Carbonate Platform- tidal flat.