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1.
桌子山中奥陶世公乌素组遗迹化石组合与古地理环境 总被引：7，自引：0，他引：7
据遗迹化石新资料 ,将内蒙古桌子山地区中奥陶世公乌素组遗迹化石自下而上划分为 8个组合 :Taenidium组合、Zoophycos组合、Volkichnium组合、H elminthopsis-Paleodictyon组合、Granularia组合、 Circulichnus组合、 Chondrites组合及 H elminthopsis组合。其中 ,H elminthopsis-Paleodictyon与 H elminthopsis两组合属于 N ereites遗迹相 ,并分别出现于陆隆 -深海盆地浊积扇与陆隆浊积扇环境 ;其余 6个组合与 Seilacher( 1 967)的 Zoophycos遗迹相相当 ,代表有机质丰富、平静而贫氧的大陆斜坡环境。遗迹组合序列和遗迹相的递变表明 ,本区在公乌素组沉积期经历了两次由陆棚边缘盆地—大陆斜坡—陆隆 -深海盆地浊积扇 (或陆隆浊积扇 )的环境演变。指出了本组遗迹化石与波兰喀尔巴阡山复理石相遗迹化石在分布上的相似性。认为 Zoophycos相各遗迹组合所赋存的泥灰岩等是很好的生油岩。 相似文献
2.
苏北盆地高邮凹陷古近系戴南组滨浅湖沉积中的遗迹化石 总被引：2，自引：0，他引：2
苏北盆地高邮凹陷古近系戴南组滨浅湖沉积中动物遗迹化石共鉴定出6个遗迹属8个遗迹种,其中1个为未定种。包括Taenidium barretti、Taenidium satanassi、Beaconites coronus、Cystichnum curvativum、Palaeophycus isp.、Planolites montanus、Skolithos verticalis和Skolithos linearis等。这些遗迹化石主要是无脊椎动物的进食迹和居住迹,呈全浮痕或半浮痕保存。根据组合特征及沉积环境分析,可识别出两个遗迹化石组合:1）Taenidium—Beaconites遗迹组合,主要由具新月型回填纹构造的进食迹组成,反映了周期性干旱气候条件下的滨浅湖沉积环境;2）Skolithos linearis遗迹组合,主要由居住潜穴组成,代表了三角洲平原—前缘沉积环境。生物扰动根据扰动特点,可分为三种类型,即1）均一型,反映了湖平面缓慢上升之后较长时间保持稳定;2）增强型,反映了湖平面整体稳定条件下的小幅度快速上升,然后保持稳定和缓慢下降;3）复合型,反映了湖平面先缓慢上升,然后缓慢下降。三角洲平原-前缘分支河道沉积序列中遗迹化石的类型、丰度、分异度和扰动指数垂向上呈规律性的变化,结合其沉积学特征分析,可分为四个沉积单元,每个沉积单元的内部物理成因构造和生物成因构造明显不同。 相似文献
3.
新疆塔里木板块西北缘早二叠世深水遗迹化石的发现及意义 总被引：3，自引：0，他引：3
《沉积学报》2000,18(4)
在新疆塔里木板块西北缘下二叠统比尤勒提群中部首次发现了大量深水遗迹化石,主要包括Glockeria Ksiazkiewicz 1968,Helminthoida sp., Megagrapton sp., Paleodictyon sp., Paleodictyon (Glenodictyum) Croaticum Ulchman 1995, Planolites sp., Protopaleodictyon sp., Scalarituba missouriensis Weller 1899, Spirophycus sp.等,代表典型深海环境的Nereites遗迹相。根据对温古尔剖面的研究,比尤勒提群下部为浅海陆棚相砂泥质灰岩、粉砂质泥岩、粉砂岩、泥晶灰岩等;而含丰富遗迹化石的比尤勒提群中部为一套深海海底扇沉积的浊积岩系夹少量硅质岩,并且在浊积扇的不同位置所产遗迹组合类型也明显不同,扇根以觅食迹为主,含大量穿相分子,扇中开始出现牧食迹,扇梢则出现特征的耕作迹;比尤勒提群上部为浅海陆棚－滨海相沉积的硅质灰岩、泥晶灰岩和砂质灰岩及粉砂质泥岩、钙质砂岩等。该套遗迹化石组合与深海浊积事件密切相关,同时表明塔里木板块西北缘早二叠世时期存在一个陆棚浅海－深海盆地沉积环境,晚二叠世时期海水向西退去形成陆相沉积。 相似文献
4.
鄂尔多斯盆地拉什仲组遗迹化石组合与古环境 总被引：4，自引：0，他引：4
首次对鄂尔多斯盆地西北缘桌子山地区中奥陶世拉什仲组的遗迹化石进行了系统研究。该组遗迹化石共有6属8种,建立了Paleodictyon遗迹化石组合。此组合以被侵蚀、改造呈斑状分布的遗迹大量存在与Paleodictyon的普遍出现为最显著的特征。遗迹化石的形态、行为习性、保存方式等分类特征、埋藏学特征等表明该组合相当于Nereites遗迹相,代表了深海远源浊流沉积环境;而在本组沉积晚期,水体开始变浅,大致为大陆斜坡－陆隆半深海浊流沉积环境。其沉积层序、沉积构造及岩性等特征说明拉什仲组为典型的浊流相沉积,并以远源相浊流沉积为主,其下部近相浊流沉积较发育。据古流向测定,自中奥陶世拉什仲组至公乌素组沉积期,重力流运动方向的变化大致反映了贺兰拗拉槽张裂的幅度在变小并渐呈收敛隆起的趋势。 相似文献
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陕西富平中奥陶统金粟山组的遗迹化石及沉积环境 总被引：3，自引：1，他引：3
陕西富平中奥陶统金粟山组产有大量遗迹化石。本文建立了第三段的Paleodictyon遗迹群落;认为二、三段的遗迹组合相当于Nereites遗迹相。同时利用遗迹化石进行了沉积环境分析。认为金粟山组的沉积环境自上而下经历了碳酸盐台地-盆地边缘-陆坡下部-陆坡上部的演变。 相似文献
7.
四川松潘马拉墩晚三叠世侏倭组的遗迹化石及沉积环境 总被引：1，自引：0，他引：1
四川松潘马拉墩晚三叠世侏倭组首次发现大量遗迹化石。本文根据不同遗迹属在不同层位中的相对丰度建立了两个遗迹组合，即Ｍｅｇａｇｒａｐｔｏｎ－Ａｒｔｈｒｏｐｈｙｃｕｓ组合及Ｎｅｏｎｅｒｅｉｔｅｓ－Ｐｈｙｃｏｓｉｐｈｏｎ组合，大致相当于Ｓｅｉｌａｃｈｅｒ（１９６７）［１］的Ｎｅｒｅｉｔｅｓ遗迹相．同时利用遗迹化石及沉积特点进行了沉积环境分析，认为侏倭组的沉积环境为大陆斜坡下部至盆地边缘。 相似文献
8.
塔里木盆地西北缘中奥陶统其浪组风暴岩中遗迹化石及其环境意义 总被引：6，自引：2，他引：4
塔里木盆地西北缘柯坪断隆中奥陶统其浪组中上段L M灰泥互层沉积地层中发育远源钙质风暴岩,其中发育属Zoophycos遗迹相的Phycodes Megagrapton遗迹组合,包括Belorhape,Circulichnus,Dendrichnites,Gordia,Granularia,Megagrapton,Phycodes,Planolites,Protopaleodictyon,Rhabdoglyphas等遗迹属。该组合遗迹形态主要为分枝迹,习性以觅食迹为主,显著特点是包含多种深水遗迹分子。这些特征与以往报道的风暴岩中遗迹组合特征有明显的差别。该组合反映其浪组风暴岩形成于滨外风暴浪基面以下水体较深且水动力较弱的静水地带。此组合可以成为判定远源风暴岩以及区分事件和正常灰岩的良好辅助标志。 相似文献
9.
The palaeoenvironmental significance of trace fossil assemblages in the flysch deposits of the Upper Cretaceous of the Sistan ocean – the Sefidabeh basin in the Sistan Suture Zone SSZ in Eastern Iran – has been assessed for the first time. The Sefidabeh basin of turbidite origin consists of 10 sedimentary facies, which can be grouped into 3 facies associations (FA) representing submarine channel-related facies associations (FA1), lobe-related facies associations (FA2), distal fan-basin floor facies associations of a deep-water turbidite system (FA3). Thirty three ichnogenera, with many ichnospecies, have been identified in this deep sea succession: Alcyonidiopsis, Arthrophycus, Asterostoma, Belorhaphe, Bergaueria, Cardioichnus, Chondrites, Cosmorhaphe, Desmograpton, Gyrophyllites, Halopoa, Helminthopsis, Helminthorhaphe, Laevicyclus, Lophoctenium, Mammilichnis, Megagrapton, Multina, Nereites, Ophiomorpha, Palaeophycus, Planolites, Phycodes, Phycosiphon, Paleodictyon, Rutichnus, Scolicia, ?Strobilorhaphe, Taenidium, Teichichnus, Thalassinoides, Zoophycos and Urohelminthoida. Their distribution is clearly linked with lithofacies and depositional palaeoenvironments. Changes in trace fossil assemblages and ichnocoenoses follow different environments of the turbidity system of the submarine channel to fan system of the Sefidabeh basin and are associated with variations in environmental controlling factors. Environmental controlling factors including hydrodynamic regime, oxygen level, organic content and sedimentation rates. Ten ichnocoenoses were recognized in the facies associations of the deep-sea fan system of this study. Taking into consideration the diversity, bioturbation level, and colonization order of bioturbated beds and the obvious deepening of the deep-sea depositional system from inner to outer parts of the succession, ichnocoenoses can express a bathymetric trend from shallower to deeper parts, and from higher-to-lower hydrodynamic condition of deep-sea fan systems of the Sefidabeh basin. This study reveals important sedimentological and ichnological features of turbiditic systems in deep sea settings of Iran and permits the development of predictive models for the palaeoenvironmental significance of trace fossil assemblages that can be readily translated to analogous depositional systems in the surface/subsurface. 相似文献
10.
西准噶尔复理石相遗迹化石主要分布于上泥盆统-下石炭统塔尔巴哈台组以及石炭系的包古图组、太勒古拉组和哈拉阿拉特组中, 典型遗迹属包括Phycosiphon, Nereites, Megagrapton, Glockerichnus, Cochlichnus, Lophoctenium, Gordia, Chondrites, Zoophycos, Scolicia, Thalassinoides.这些遗迹化石构成具有典型深水Nereites遗迹相特征的Phycosiphon-Nereites遗迹化石组合和Megagrapton-Glockerichnus-Cochlichnus遗迹化石组合.包古图组和太勒古拉组属于海底扇中下扇扇缘-盆地平原环境; 哈拉阿拉特组和塔尔巴哈台组则属于海底扇中下扇扇叶环境.西准噶尔复理石相遗迹化石分布与鲍马序列的厚度密切相关, 在毫米-厘米级鲍马序列中, 遗迹化石属种单调且保存较差, 可见单一属的Phycosiphon或Nereites; 而在厘米-分米级鲍马序列中, 可见不同直径大小和形态上具有过渡的Phycosiphon和Nereites, 可能代表同种造迹生物不同个体发育阶段的生物遗迹.海底扇不同亚环境单个鲍马序列的厚度决定了底栖生物是否有足够的时间形成较为成熟的群落(包括一系列幼年和成年个体). 相似文献
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贵州省福泉桅杆坪地区寒武系底部牛蹄塘组黑色页岩中以炭质印模的形式保存有大量宏观后生动物化石.化石微细特征保存较差,多属于疑难化石.该化石组合以化石个体较大的蠕虫状化石和疑似杆壁虫类化石为优势分子,还常见管状类化石、遗迹化石,以及少量的软舌螺、海绵骨针等化石碎片.该化石组合紧位于镍钼多金属层之上,与遵义等地区的松林生物群(牛蹄塘组下生物群)的层位相当,化石组成基本一致,但优势生物存在明显差异.福泉地区牛蹄塘组蠕虫状化石组合的发现,丰富了寒武系牛蹄塘组的生物群面貌,为研究早期后生动物演化提供了新资料和新信息.对该化石组合的进一步研究,也必将为这种特殊生物群的古环境恢复和埋藏学研究提供有利的古生物学证据. 相似文献
12.
青海果洛、玉树地区二叠纪和三叠纪复理石相遗迹化石 总被引：10，自引：4，他引：10
本文系统描述了产自我国青海南部巴彦喀拉山脉玛沁、甘德、玛多等地二叠-三叠纪(主要是三叠纪)复理石相的遗迹化石。主要遗迹属如:Paleodictyon,(古网迹),Protopaleodictyon(原始古网迹),Megagrapton(巨画迹),Helminthoida(蠕形迹),Helminthopsis(拟蠕形迹),Helicolithus(螺旋迹)Lophoctenium(冠梳迹)清楚地证明为深海Nereits遗迹相典型代表,也是迄今为止该遗迹相在我国发现最丰富的地区。遗迹化石产地玛沁、玛多深海相位于我国两个板块之间的对接带附近,说明遗迹化石同古构造的关系。 相似文献
13.
辽河油田西部凹陷沙三段沉积相及演化 总被引：8，自引：3，他引：8
西部凹陷沙河街组三段沉积厚度很大，分布范围广，是深层储层重要组成部分。根据地球化学、化石组合及生态习性分析，沙三段沉积期处于暖湿气候的较深水还原湖泊环境。主体物源来自西侧，发育了一系列自西而东的扇三角洲砂体。根据沉积背景和岩心描述所建立的沉积层序，可确认这一沉积砂体的主要类型为浅水至较深水环境的水进型扇三角洲沉积，根据扇3角洲的岩性、沉积层序和形态可进一步划分为扇根、扇中和扇端3个亚相带。砂体发育主要受西侧物源控制，发育了多个扇三角洲体系。这些扇三角州砂体邻近生油洼陷，与烃源岩直接接触，有利于油气的优先富集，可形成一系列岩性一构造圈闭，不失为深层油气勘探的有利区带。 相似文献
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A petrographic study of 157 samples from the Early to Middle Eocene deep-marine sandy systems, Ainsa–Jaca basin, Spanish Pyrenees, shows that each system has a characteristic petrofacies. Three main petrofacies are recognized. Petrofacies 1 sandstones comprise mainly siliciclastic grains (≥80%), subordinate terrigenous carbonate grains and negligible intrabasinal grains. Petrofacies 2 hybrid arenites are characterized by significant amounts (≥10%) of intrabasinal carbonate grains. Petrofacies 3 calcilithites contain relatively abundant (≥10%) extrabasinal carbonate grains. On the basis of these petrofacies, a revised correlation of the sandy systems is proposed between the more proximal Ainsa basin, and the more distal Jaca basin sediments, now separated by the Boltaña anticline, across which it is impossible to actually trace out individual beds or sandstone packages between both basins. The arenite composition in the Ainsa and Jaca basins is interpreted as being controlled mainly by synsedimentary tectonic processes that led to changes in sediment sources during basin evolution. 相似文献
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民和盆地下白垩统首次发现7个遗迹属，早期的朱家台组为Skolithos-Planolites组合，中期的盐锅峡组为Thalassinoides-Palaeophycus组合，晚期的红古城组为Planolites-Scoyenia组合，这些遗迹属在纵向上可以出现相行为，表明水深不是主控因素，而是古气候的作用。 相似文献
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The most extensive ichnofauna yet recorded from a deep water Lower Palaeozoic sequence occurs within the distal turbidites of the Lower Silurian Aberystwyth Grits Formation of Central Wales. The strata contain an abundant assemblage comprising 25 ichnogenera: Asteriacites, Bergaueria, Chondrites, Cochlichnus, Cosmorhaphe, Glockerichnus, Gordia, Helicolithus, Helminthopsis, Helminthoida, Hormosiroidea, Lorenzinia, Megagrapton, Monomorphichnus, Neonereites, Nereites, Palaeophycus, Paleodictyon, Planolites, Protopaleodictyon, Spirorhaphe, Spirophycus, Squamodictyon, Subphyllochorda, Taphrhelminthopsis; 36 ichnospecies are described, three of which (Asteriacites aberensis, Helminthopsis regularis, Cosmorhaphe elongata) are new. The inorganic sedimentary structures and trace fossils of some 418 sandstone beds were examined in detail; 16 per cent of the beds commence with Divisions A or B and 84 per cent with Division C of the turbidite sequence. This indicates a relatively distal environment, mainly receiving low velocity turbidity currents, and favouring trace fossil preservation. The most common traces were Helminthopsis, Paleodictyon, and Squamodictyon which were found on 46 per cent, 34 per cent, and 19 per cent of the beds examined. Data from this, and other recently described sequences, confirms that there was a gradual increase in trace fossil diversity in the deep oceans throughout the Lower Palaeozoic, in contrast to the situation in shallow water shelf seas where a peak was reached as early as the Lower Cambrian. 相似文献
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Imad Bouchemla Mohamed Bendella Madani Benyoucef Olev Vinn Bruno Ferré 《Proceedings of the Geologists' Association. Geologists' Association》2021,132(2):207-226
The Upper Emsian to Frasnian Ia-Ib strata of the Marhouma area (or “km 30” outcrop), exposed in the Ougarta Range (SW Algeria) belong to the Chefar El Ahmar Formation. On the basis of distinct lithological and palaeontological features, this formation is subdivided into three members (Lower Marly Limestones Member, Middle Marly Limestones Member, and Upper Marly Limestones Member). The studied beds show low to moderate diversity of trace fossil assemblage which contains thirteen ichnotaxa: Chondrites intricatus, Chondrites isp., Chondrites cf. targionii, Circulichnis cf. montanus, Cochlichnus isp., Neonereites biserialis, Neonereites multiserialis, Nereites isp., Palaeophycus isp., Planolites isp., Thalassinoides isp., Zoophycos aff. cauda-galli, and Zoophycos isp. A. The two latter ichnotaxa are the most common trace fossils in the assemblage and occur at three different levels showing different bioturbation intensities. The first Zoophycos-bearing level (Zl 1) is characterised by an overall high bioturbation intensity reflecting a very high oxygenation rate and nutrient supply, allowing the development of large and dense Zoophycos specimens. The second Zoophycos-bearing level (Zl 2) has a considerable reduction of bioturbation intensity as compared to the previous level, with an abundance of Chondrites, which is probably due to radical palaeoecological changes that suggests dysoxic and stressful conditions. The third Zoophycos-bearing level (Zl 3) is characterised by an overall moderate bioturbation intensity. The distribution of trace fossils was influenced by lithology, sedimentation rate, energy level (storm events), bottom oxygenation, and nutrient supply. The lithofacies and trace fossils of the Chefar El Ahmar Formation both indicate a depositional environment fluctuating from the lower shoreface to lower offshore zone. 相似文献
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Aram BAYET-GOLL Paul M. MYROW Guillermo F. ACE?OLAZA Reza MOUSSAVI-HARAMI Asadollah MAHBOUBI 《《地质学报》英文版》2016,90(5):1572-1597
The Lower Ordovician Shirgesht Formation in central Iran is composed of siliciclastic and carbonate rocks deposited in diverse coastal and marine shelfal environments (tidal flat, lagoon, shoreface, offshore-shelf and carbonate ramp). Five facies associations contain diverse ichnofossil assemblages that show distinct proximal to distal trends formed in a wide range of physical-chemical conditions. The ethological groups of trace fossils in the Shirgesht Formation reflect a gradient of depositional stress conditions across a wave-influenced shoreline and shelf. Deposits of wave-influenced environments make up a significant component of the geological record of shallow marine settings, and the ability to determine paleoenvironments in detail in such successions is critical for reconstruction of depositional histories and sequence-stratigraphic interpretation.The Cruziana ichnofacies of the study shows highly diverse suites that record the establishment of a benthic community under stable conditions and a long-term colonization window. The Skolithos ichnofacies recognized is a low diversity opportunistic ichnocommunity suite that resulted from colonization after tempestite deposition in a stressed environment. The strata record an onshore to offshore replacement of the Cruziana ichnofacies (with abundant feeding traces of deposit-feeders) by the Skolithos ichnofacies (dominated by suspension-feeders and predators). A transitional zone between the two ichnofacies coincides with the offshore-transition/distal lower-surface deposits. The distribution of ichnofacies, the diversity and range of ethological characteristics reflected by the ichnogenera, and the wide range of wave-dominated coastal facies demonstrate the potential to use individual trace fossils and ichnofacies for significantly refined palaeoenvironmental analysis of wave-dominated coastal settings, particularly in Ordovician successions. 相似文献
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准噶尔盆地东北缘发育的下石炭统南明水组沉积岩是对晚古生代北疆地区洋壳俯冲消减作用的沉积响应。本次研究在南明水组地层中发现丰富的遗迹化石:Scalarituba, Planolites,Cosmorhaphe,Spirophycus和Helminthoida。岩性组合特征和遗迹化石所代表的遗迹相,反映了南明水组的主要沉积相类型为扇三角洲前缘、浅海、深海-半深海,从下往上为一个由浅变深再变浅的不对称的完整层序。南明水组的岩性、层序演化以及砂、泥岩地球化学特征表明,该套地层发育的构造背景为弧后盆地。早石炭世准噶尔盆地东部存在的洋壳俯冲消减作用是研究区弧后盆地发育的动力机制。 相似文献