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在中国新疆和华南海相泥盆系中识别出交切、并列、叠覆遗迹组构（相关遗迹组构类）和欧氏、拓扑遗迹组构（本体遗迹组构类）．通过对火山碎屑风暴岩中复合交切遗迹组构的研究发现，共生组合在一起的遗迹化石，可划分出６个遗迹阶层，具有不同的先后、世代关系和指相意义．拓扑遗迹组构分析表明，庞大的雕画迹家族可归并为３个拓扑类，它们分别同胚于线、树、网．雕画迹从线至网的拓扑形态谱系结构，分别代表深水或缺氧环境中，造迹生物寻觅式、探索式和诱捕式的觅食行为．研究表明：遗迹组构分析对副层序、凝缩段、不同海平面变化速度形成的海进体系域和高水位体系域的识别和高频旋回的研究有重要作用 相似文献
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Diagenetic signatures of stratal surfaces in the Upper Jurassic Fulmar Formation, Central North Sea, UKCS 总被引：2，自引：0，他引：2
FIONA E. BURNS STUART D. BURLEY ROB L. GAWTHORPE JOHN E. POLLARD 《Sedimentology》2005,52(6):1155-1185
Sedimentation rate and changes in relative sea level affect early diagenetic cementation along key stratal surfaces within the deeply buried Upper Jurassic Fulmar Formation, South Central Graben, UKCS. As a result of the bioturbated nature of the shallow marine strata, variations in ichnofabrics and cross-cutting relationships between trace fossils are important in identifying and correlating stratal surfaces. Two transgressive and two regressive surfaces/sequence boundaries were studied, using petrographical, mineralogical and geochemical techniques. Cements, including early diagenetic pyrite framboids, grain-rimming apatite, microcrystalline dolomite and ankerite, occur at, above and immediately below both transgressive and forced regressive surfaces/sequence boundaries. Breaks or subdued rates of sedimentation associated with both types of surfaces meant that the sediment package resided within early diagenetic zones for prolonged periods of time, enhancing diagenetic reactions at and below the surfaces. The distribution of ankerite, despite being a deep-burial cement, was primarily controlled by concentrations of bioclasts that are particularly abundant at transgressive surfaces. The diagenetic character of the forced regressive surfaces/sequence boundaries is more complex than that of the transgressive surfaces, both in terms of mineralogy and paragenesis. This is attributed to the superimposition of diagenetic assemblages as a result of erosion, re-sedimentation and sediment by-passing. Although the diagenetic signature of the surfaces has been modified by dissolution/replacement reactions during deep burial, early diagenetic signatures can still be distinguished. 相似文献
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Previous studies on multiple sulfur isotopes (32S, 33S, and 34S) in sedimentary pyrite at the end-Permian suggested a shoaling of anoxic/sulfidic deep-water contributing to the extinction. This scenario is based on an assumption that the sedimentary sulfur cycle was largely controlled by benthos activity, though a stratigraphic correlation between the sulfur records and ichnofabrics of the sediments at the end-Permian has not yet been examined. We report the multiple sulfur isotopic composition of pyrite in the Permian–Triassic boundary interval at Chaotian, South China. Our data can be generally explained by a mixing of sulfur in sulfide from two different sources: one produced via sulfate reduction in an open system with respect to sulfate and the other produced in a closed system. In particular, the former with the substantially low δ34S (<−40 ‰) and high ∆33S (up to +0.100 ‰) values was likely produced via water-mass sulfate reduction or via sulfate reduction in oxic sediments with common burrows. The frequent occurrence of small pyrite framboids (mostly <5 μm in diameter) in the Lopingian (Late Permian) Dalong Formation of deep-water facies supports the enhanced water-mass sulfate reduction in an anoxic deep-water mass. The negative ∆33S values are observed only in the oxic limestones, and no substantial ∆33S change is observed across the extinction horizon despite of the disappearance of bioturbation. Our results are apparently inconsistent with the previous shoaling model. We expand the model and infer that, when the deep-water was sulfidic and its shoaling rate was high, a substantial amount of hydrogen sulfide (H2S) was supplied onto the shelf via the shoaling; that resulted in the positive ∆33S value of the bulk sediments. The observed ∆33S variation on a global scale suggests a substantial variation in H2S concentration and/or in upwelling rate of shoaling deep-waters during the Permian–Triassic transition. 相似文献
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河南西峡盆地上白垩统马家村组沉积厚度巨大,达1 960 m,由辫状河沉积、曲流河沉积和湖泊沉积组成。在河流与湖泊沉积中,发育丰富的遗迹化石,共6种类型,分别为Skolithos linearis、Cylindricumichnosp、Palaeophycus tubularis“J”形潜穴、垂直分枝潜穴和垂直螺旋潜穴。从形态分析,大多数为居住迹,按照遗迹化石产出岩层的岩性、扰动特征和残留遗迹等总体特征,将所发现的遗迹化石层划分为两类遗迹组构,即软底组构和僵底组构。前者主要发育在纹层状极细砂岩和粉砂岩中,潜穴密度大,属种单一,包括Skolithos组构和Palaeophycus组构;后者主要发育在厚层泥岩中,潜穴密度较大,类型稍多,包括由Cylindricum ichnosp、垂直分枝潜穴J形潜穴和垂直螺旋潜穴所组成的遗迹组构。与报道过的其他地区陆相遗迹化石的对比表明,随着时间的推移,河流沉积中的组构特征在白垩纪有明显变化,而浅湖沉积中的遗迹组构表明造迹生物的扰动能力显著加强。 相似文献
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大港油田中部滩海新近纪古湖泊发育的证据 总被引：1，自引：0，他引：1
大港中部滩海新近系层系是重要的油气后备勘探领域和战略接替区.前人普遍认为新近系层系发育曲流河和辫状河沉积.借鉴渤海海域浅层油气勘探经验, 基于遗迹组构、微古生物、生物有机化合物、碳氧同位素以及地震等地质资料分析, 认为中部滩海东部发育开阔的古湖泊, 其证据为: 发育见于国内外浅湖环境的典型的Palaeophycus遗迹组构; 发现丰富的见于正常浅湖环境的浮游绿藻化石; 发现较多的仅分布在古代和现代湖泊中的介形类——Candona、Cypris; 干酪根类型、生物有机化合物、碳氧同位素以及地震等地质资料也证明了古湖泊的存在.馆陶组中、晚期至明化镇组沉积早期为湖泊逐渐扩张达到鼎盛发育的时期. 相似文献
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豫西济源地区中三叠世油房庄组遗迹组构及其环境解释 总被引：3，自引：1，他引：3
河南济源地区中三叠世油房庄组发育了一套滨浅湖相的砂泥岩沉积，在该组上段紫红色与黄绿色砂泥岩沉积中发现了大量的遗迹化石。其中高能砂质滨湖沉积中识别出6种遗迹组构:斑状生物扰动组构、Skolithos isp.-Planolites montanus组构、Skolithos verticalis组构、Planolites beverleyensis组构、Skolithos isp.组构和Palaeophycus annulatus 遗迹组构，它们可归入陆相Skolithos遗迹相；极浅湖泥岩夹粉砂岩沉积中识别出3种遗迹组构: Skolithos linearis遗迹组构、Taenidium barretti遗迹组构和植物根迹组构，它们可归入陆相Scoyenia遗迹相。 相似文献
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晋中南地区上石炭统-下二叠统太原组碳酸盐岩中遗迹组构及其沉积环境 总被引：3，自引：1，他引：2
晋中南地区上石炭统-下二叠统太原组是一套海陆交互相含煤地层,其中碳酸盐岩中发育丰富的遗迹化石。通过对山西太原西山和陵川附城一带露头剖面遗迹化石的详细观察、鉴定与分析,共识别出10个遗迹属、14个遗迹种,其生态类型包括进食迹10种、觅食迹和居住迹各2种。基于各灰岩层中遗迹化石的组成、产状、大小、潜穴充填物的成分及颜色、宿主岩的岩性等特征,建立了4种遗迹组构及其沉积环境分布模式:类型A:大型Zoophycos-Thalassinoides遗迹组构,出现于海湾(潟湖)及潮坪沉积环境;类型B:大型Zoophycos-Planolites遗迹组构,发育在海平面至正常天气浪基面附近区域的浅海上部沉积环境或水体浅且较平静的局限碳酸盐岩台地环境;类型C:中型Zoophycos-Teichichnus遗迹组构,主要产生在正常天气浪基面之下、风暴浪基面之上的浅海中部沉积环境;类型D:小型Zoophycos-Chondrites遗迹组构,形成于风暴浪基面之下、水体较深且贫氧的浅海下部沉积环境。这一成果可以为精细研究本区太原组的沉积环境变迁史提供重要的生物学信息,也可为煤与煤层气的生成环境提供生物学记录方面的科学依据。 相似文献
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近十年来,中国遗迹学的研究取得许多新进展和新认识,重要成果概述如下: (1)在显生宙海相和过渡相沉积中新识别出84个遗迹属和211个遗迹种,新建28种遗迹组合及26种遗迹组构;在中生代和新生代陆相冲积扇、河流与湖泊沉积中识别出44个遗迹属和107个遗迹种,新建22种遗迹组合及10种遗迹组构;(2)论述了寒武纪底质革命对早期底栖生物的进化和生态效应的影响;(3)提出了3种古氧相(常氧相、贫氧相和厌氧相)的遗迹化石响应关系及其形成的沉积背景;(4)在华北下二叠统太原组灰岩中发现了大量成因与微生物相关的碳酸盐岩微形体,在动藻迹(Zoophycos)潜穴充填物中识别出球状、杆状、簇状、网状、瓶状和似脑球状6种微形体,描述了由造迹者与共生微生物一起进行一系列生命活动行为所形成的复杂精美的生物成因构造;(5)揭示了复杂遗迹化石动藻迹(Zoophycos)从浅阶层迁移至深阶层与从浅海迁移至半深海-深海同步的演化规律;(6)提出了滨-浅海和湖泊环境中风暴与浊流事件沉积序列中以及P/Tr界线附近遗迹化石的组成与分布特征,并论证了P-Tr事件前后遗迹化石及其造迹生物生态系统的演变规律,为晚二叠世末生物大灭绝后的生态系统复苏过程提供了可靠的遗迹学信息;(7)在华东、华北和西部地区多处新发现侏罗纪和白垩纪大量兽脚类、蜥脚类和鸟脚类恐龙足迹群;(8)在华北地台中元古界和上二叠统-下三叠统碎屑岩中识别出多种微生物成因沉积构造;(9)详细分析了碎屑岩和碳酸盐岩储集层中的生物扰动作用和遗迹组构及其对储集层物性的影响,建立了生物扰动变化三维地质模型,并提出了生物扰动型储集层的表征与研究方法。上述研究成果极大地促进了中国在遗迹分类学、遗迹相、遗迹组构、地微生物以及遗迹学在事件沉积和油气储层应用研究等方面的发展和进步。 相似文献
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豫西北奥陶系马家沟组三段遗迹组构及沉积演化规律 总被引：2，自引：0，他引：2
豫西北奥陶系马家沟组三段碳酸盐岩中遗迹化石丰富。在对野外露头实地观测的基础上,利用室内切片、薄片分析等对研究区奥陶系马家沟组三段遗迹化石、遗迹组构及沉积演化规律进行研究。结果表明:(1)研究区奥陶系马家沟组三段共鉴定出遗迹化石类型7属10种。(2)根据遗迹化石的分子组成、产状、共生关系、丰度与分异度以及生物扰动的程度,结合沉积学特征分析,共识别出遗迹组构4种:Psilonichnus遗迹组构主要发育在潮上带与潮间带上部(高潮坪)低能的沉积环境;Thalassinoides遗迹组构代表潮间带中-下部和台内滩等高能沉积环境;Helminthopsis遗迹组构反映局限碳酸盐岩台地内的潟湖和开阔台地内的滩间海等较低能的沉积环境。Helminthopsis-Chondrites遗迹组构揭示开阔碳酸盐岩台地中滩间海-台内洼地等非常低能的沉积环境。(3)建立了研究区马家沟组三段的层序地层格架,并在层序格架内对遗迹组构和沉积微环境的演化规律进行了研究,解译出研究区马家沟组三段经历了两次区域性的海侵—海退;综合岩石类型、岩石序列组合、沉积构造、生物化石、遗迹化石组合、遗迹组构等资料,建立了研究区奥陶系马家沟组三段各遗迹组构与沉积微环境的三维相模式。这对研究华北奥陶系沉积环境与沉积演化具有重要的借鉴意义。 相似文献