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The dinosaur fauna at Dashanpu is found in lower Shaximiao Formationof middle Jurassic, which consists of a suite of terrigenous clastic sediments.composed mainly by purple mudstone with greyish--green, medium--to micro-grained sandstone and siltstone intercalation. The compositional and texturalmaturity of sandstone is not high. The characteristics of paleontology andpetrology show that the lower Shaximiao Formation belongs to alternatedeposits of fluvial and lacustrine facies. The dinosaur fauna occurs in... The dinosaur fauna at Dashanpu is found in lower Shaximiao Formationof middle Jurassic, which consists of a suite of terrigenous clastic sediments.composed mainly by purple mudstone with greyish--green, medium--to micro-grained sandstone and siltstone intercalation. The compositional and texturalmaturity of sandstone is not high. The characteristics of paleontology andpetrology show that the lower Shaximiao Formation belongs to alternatedeposits of fluvial and lacustrine facies. The dinosaur fauna occurs in micro--grained feldspatholithic sandstone,which is rich in mica fragments, matrix interstitial. Wave--ripple crossbedding, micro--wavy bedding and medium--to large--scale tabular crossbedding are clearly seen. Petrological characteristics indicate that it belongsto lake--shore shallow--bank deposit under lower energy condition. At that time, the dinosaurs lived on a lake--shore plain with profusewater and grass. The reason for leading them to a mass death is supposed tobe poisoning by plants with abundant arsenic the dinosaurs ate. Their remainswere buried in the lake--shore shallow--bank. The abnormal death and theburial in situ in shallow--bank of low energy are the main factors to providea great deal of well preserved dinosaur fossils in this region. 大山铺恐龙动物群产于中侏罗统下沙溪庙组中,该组为一套陆源碎屑沉积,以紫红色泥岩为主,夹有多层浅灰绿色中一微粒砂岩和粉砂岩,属河流相和湖泊相交替沉积。恐龙动物群赋存于微粒长石岩屑砂岩中,砂岩富含云母片,杂基填隙,浪成沙纹层理和微波状层理发育,并具中一大型板状交错层理,属低能湖滨浅滩沉积。当时恐龙生活于水,草丰茂的湖滨平原上,因食富砷植物引起中毒并导致恐龙大批死亡,遗体埋藏于湖滨浅滩中。异常死亡和原地埋藏于低能浅滩,这是造成本区恐龙化石的数量丰富和保存完整的根本原因。 Fuyu Oil Play belongs to the 4th Member ( K1q4 ) of Quantou Formation, Songhuajiang River Group of Cretaceous. It is one of the major plays in the southern Songliao Basin, After the examination on numerous thin sec-tions of rocks, the following understandings on the diagenesis of the oil play have been achieved. 扶余油层是松辽盆地南部主要开采和勘探的目的层,作者通过大量岩石薄片的研究,认为该油层是由砂岩、粉砂岩、泥岩及其过渡岩类组成的一套韵律沉积;砂岩的矿物成分和结构,明显地影响着物理和化学成岩作用;自生高岭石、自生石英和方解石分布广、含量大,是对储集性能影响较大的胶结物;而富含长石、岩屑和矿物成熟度低,则是本区砂岩的特点。 The sandstone in Xuer section was mainly dominated by micropores. There were fewer feldspar and detritus solution pores and rare or no carbonate solution pores. This phenomenon has been explained by the steady carbon isotope of calcite and thermodynamics theory. The samples, the porosity of which is over 5%, must contain chlorite coatings and display high water saturation as well as low electric resistvity, which leads to mismisjudging gas an water layer. Detailed petrology researches show that clay minerals... The sandstone in Xuer section was mainly dominated by micropores. There were fewer feldspar and detritus solution pores and rare or no carbonate solution pores. This phenomenon has been explained by the steady carbon isotope of calcite and thermodynamics theory. The samples, the porosity of which is over 5%, must contain chlorite coatings and display high water saturation as well as low electric resistvity, which leads to mismisjudging gas an water layer. Detailed petrology researches show that clay minerals play a particular role in the process of diagenesis. The storage capacity of samples with clay is better than that with carbonates. A new concept of "pore life-span" is proposed and its significance in petroleum exploration is discussed in this paper. 须二段砂岩以徽孔隙为主,少量的长石、岩屑溶孔,不见或罕见碳酸盐矿物的溶孔,利用同位素资料和热力学理论解释了这种现象。凡孔隙度大于5%的样品,就有绿泥石包壳发育,该层段表现为低电阻率和高含水饱和度,导致气、水层的误判。详细的岩石学研究使我们认识到粘土矿物在成岩过程中起到的特殊作用。自生粘土发育的样品,不论其产状如何,都比不含粘土而富含碳酸盐矿物的层段的样品储集性能好。提出了孔隙寿命的概念,并讨论了它在油气勘探中的意义。
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