地史学：第2章 沉积古地理学-1

1、第2章 沉积古地理学-1Sedimentary palaeogeography,2.1 概念与定律 2.2 相标志 2.3 沉积环境/互动,给你一 块标本 还我一 片天地,1 Sed. Environments/沉积环境 2 Sedimentary facies/沉积相 3 Facies changes and analysis of sed-facies/相变和相分析 4 Walthers law/瓦尔特定律 5 Uniformitarianism/均变论,2.1 概念与定律 Concepts and laws,1 沉积环境(sedimentary environments): 一个具有独特

2、的 物理、化学和生物 特征及其组合的自然地理单元,2 沉积相(Sedimentary facies)反映沉积记录成因（环境和条件） 的原生岩石和生物特征的综合。即原生沉积记录成因的物质表现,记录: 生物相/biofacies; 遗迹相/ichnofacies; 岩相/lithofacies, petrofacies,成因: 环境相(environmental facies); 作用相/processing facies,Carbonate facies,Shale facies,Sandstone facies,Shale 方法; 原理,时间上的相随反映空间上的并列 指导和检验相分析工作(剖面

3、上+平面上),4 瓦尔特定律/相对比原理(J Walther, 1894) :只有那些目前可以观察到是相互毗邻的相和相区，才能原生地重叠在一起,Walthers law or law of facies correlation : Only those facies and facies-areas can be superimposed primarily which can be observed beside each other at the present time (translated by Middleton, 1973); in other words, facies occ

4、urring in a conformable vertical sequence of strata were formed in laterally adjacent environments., 整合/Stratigraphical conformities 渐变/Gradual transgression/regression,冲积,5 Uniformitarianism,“The past history of our globe must be explained by what can be seen to be happening now” (James Hutton). It

5、 was named Uniformitarianism by Charles Lyell (1830; Hutton, 1795),类比 分析,Uniformitarianism-1?,将今论古,Brachiopods（Productida, O3-P),现代腕足动物，各种水深均能生存(0-6000m+), 但以深水为主;古生代腕足类大多数生活在盐度正常的浅海环境中，但中生代以来发现它们与某些深水类别共生,Uniformitarianism-2?,Uniformitarianism-3？,Mars,Sedimentationon the Mars,将地论天,Uniformitarianism

6、-4?,Deep biosphere,Nature, 2011, 476:176-180,Uniformitarianism 类比分析The present is the key to the past,将今论古 将古论今 将古论古 将今论未来 将天论地 将地论天 将表层论深部 将深部论表层,跨时间域 ? or !,跨空间域? or !,The earth is the key to the celestial bodies,What are your comments?,第2章 沉积古地理学-1Sedimentary palaeogeography,2.1 概念与定律 2.2 相标志 2.3

7、 沉积环境/互动,给你一 块标本 还我一 片天地,2.2 相标志/Sed. facies indicators,相标志: 反映地层形成环境的原生沉积特征 Sed. Facies indicators: the primary biologic, physic 深水/浅水 干旱/潮湿; 温暖/寒冷 氧化/还原; 高能/低能,环境,特,征,意,义,生物标志/Biogenic indicators,stenohaline: corals, brachiopods, cephalopods, bryozoans types (nautilus, ammonite) euryhaline: bivalv

8、es, gastropods, cyanobacteria associations： bivalves+plants; corals+brachiopods+cephalopods abundance body fossils diversity postures D3k, E. Junggar,Tuffite with plants and radiolarian; D3h, W. Junggar,文饰 组合 与 保存,Sulfate-reducing bacteria,Diatom, 2 microns, lake to sea,burrows,trails,概念 分类 科学价值,遗迹化

9、石: 地史时期生命活动留下的遗迹和遗物 A trace fossil is a morphologically recurrent structure resulting from the life activity of an individual organism (or homotypic/同类的生物) modifying the substrate (Bertling et al., 2006),遗迹化石 Trace fossils,Coprolite, 250Ma,Stone axes, 1Ma; India,eggs,woodground,hardground,Stromatoli

10、tes,10 ,Imprint: a tool mark. Dead body of a starfish is the tool,Beach of the Sapelo Island, Georgia,分类/Classifications of trace fossils,保存分类 Preservational classification 习性分类 Ethological classification 形态分类 Morphological classification,Preservational classifications,全浮雕,半浮雕,外生迹,表生迹,内生迹,底生迹,Etholo

11、gic Classification 习性分类,Resting-cubichnia; crawling-repichnia; grazing-pascichnia; Feeding-fodinichnia; dwelling-domichnia; traps escaping-fugichnia,Morphologic classification,Euclidean geometric terms：length, diameter, height, curve , angle etc. Topologic terms: dimension, connected component, bran

12、ch number, division-point, nondivision-point, points index, closed and bounded surfaces, Eulars character etc.,Yi-Ming Gong, Yuan-Lan Si. 2002. Classification and evolution of metazoan traces at a topological level. Lethaia, 35 (3): 263-274 黄定华，龚一鸣. 1998. 遗迹化石的形态-结构分析与拓扑分类.中国科学D辑, 28(1):60-66.,Gener

13、al form,Yangziichnus,Zoophycos,Cosmorhaphe,Chondrites,鉴定,Details of the organic traces,Ophiomorpha nodosa,Spongeliomorpha iberica,Thalassinoides suevicus,Skolithos, Taenidium serpentinum, Ancorichnus ancorichnus,Significant prompts遗迹化石的鉴定和分类应建立在标本好而且多的基础上，并应从不同切面上仔细观测上述多方面的特征,命名/ Nomenclature,两级分类单位

14、： 遗迹属 (ichnogenusichnogen. / igen. ) 遗迹种 (ichnospecies ichnosp. / isp.) 命名：林奈的binominal nomenclature 如属名: Scoyenia gracilis White, 1929（属的模式种） Quebeeichnus Hofman, 1972 （未指定） 代表遗迹属的词尾：-craterion, -ichnus, -ichnites, -ichnium,科学价值/Trace fossils values, 重塑古环境/Reconstructing palaeo-environments 生物环境间的相互作用/Interaction between organisms 深水/浅水 干旱/潮湿; 温暖/寒冷 氧化/还原; 高能/低能,环境,特,征,意,义,生物标志/Biogenic indicators,stenohaline: corals, brachiopods, cephalopods, bryozoans types (nautilus, ammonite) euryhaline: bivalves, gastropods, cyanobacteria associations：