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1.
本文为笔者根据第三十一届国际地质大会的200余篇与沉积学相关的论文摘要综合编写而成。评述了当代沉积学研究的最新进展与发展主要，主要包括:碎屑岩、碳酸盐岩及混合沉积的环境变化及其演变；沉积盆地分析与大地构造沉积学；层序地层学；冰川事件沉积学；全球变化沉积学；环境沉积学；资源沉积学；生物礁及白云岩成因；碳酸盐成岩作用等。重点阐述了现代沉积学研究应向多学科交叉渗透、多种高新技术的引用和多领域应用的方向发展。未来沉积学研究以人类的生存与发展所依托的环境、气候和资源为服务对象，才会有更加旺盛的生命力和美好的未来。  相似文献   

2.
沉积相研究发展与人类的生存和矿产资源勘探开发密切相关。该文在简单回顾了近200年的沉积学发展历史的基础上,分析了国际和中国沉积学关注的学科热点问题。国际沉积学会重点关注的问题主要包括国际大洋钻探计划、深-时气候变化与全球海平面变化、源-汇系统、碳酸盐岩沉积环境、混合沉积、微生物岩、陆架边缘三角洲、重力流、细粒沉积、构造-沉积学、火山沉积学和地震沉积学。中国的沉积学家的研究则主要着眼于陆相沉积、陆相盆地沉积模型、南海沉积、不同类型盆地沉积过程差异、浅水三角洲与陆架边缘三角洲、不同尺度与不同地质年代源-汇系统、中国南部小型克拉通盆地内的碳酸盐岩沉积等问题。总体上,当前研究热点主要包括:(1)陆相沉积环境;(2)滨岸与浅水沉积;(3)深水沉积与事件沉积;(4)碳酸盐岩沉积;(5)沉积过程与新方法。开展多类型盆地沉积动力学研究、创建具有中国区域特色的陆相沉积学理论体系、多学科交叉渗透、开展综合定量沉积学研究、创新沉积学研究方法和高效油气勘探开发是未来中国沉积研究的主要发展态势,沉积学这一重要的地质学分支学科将会更有效地指导油气资源勘探和开发。  相似文献   

3.
【意义】第21届国际沉积学大会于2022年8月在北京召开。会议热点主要包括深时气候与环境、构造与火山沉积学、环境与灾害沉积学、生物沉积过程、陆相碎屑沉积体系、海相碎屑沉积体系、海相碳酸盐岩沉积、现代沉积过程、资源沉积学、沉积地球化学和地球科学研究新方法技术。【进展】与往届国际沉积学大会相比,深时气候演化以及中新生代温室效应和极热事件、新生代亚洲—青藏高原气候变化机制及沉积响应、特提斯构造与沉积作用、亚洲大陆边缘源—汇系统与沉积机制、碎屑沉积和生物沉积作用、海盆与湖盆混合沉积过程与时空差异、火山沉积学与灾害沉积学、有机—无机相互作用与碳中和、大数据与人工智能等方面受到广泛关注,深海油气资源及沉积矿床等相关研究得到了快速发展。【结论与展望】国际沉积学大会的前沿动态和热点问题综合分析表明,未来中国沉积学研究应当不断推动沉积地质学由定性描述向定量分析发展,创建具有中国区域地质特色的沉积学理论体系,为确保我国能源资源安全作出地质贡献。  相似文献   

4.
中国沉积学的今后发展:若干思考与建议   总被引：39，自引：6，他引：39  
孙枢 《地学前缘》2005,12(2):3-10
在简述沉积学国内外研究进展基础上, 文中提出了中国沉积学今后发展需要加强和重视的研究领域。就沉积类型而言,需要加强和重视包括陆相沉积、碳酸盐沉积、近岸和浅海硅质碎屑沉积、深海沉积的研究;新的发展方向包括沉积盆地、古气候与沉积作用、前寒武纪沉积、人类生存环境沉积学、区域沉积学和全球沉积学。文中还对中国如何继续深化这些研究提出了一些需注意的问题,如需长期不懈地对一些科学问题和沉积现象深入研究和观测,以及重视新方法及新技术的应用等。在结语中对未来中国沉积学发展提出了10条建议。  相似文献   

5.
沉积学进展中的若干主要方向   总被引：3，自引：0，他引：3  
本文提出沉积学学科的几个主要进展方向几乎都与能源勘查的促进和刺激有关。已成为油气勘探有效新方法的层序地层学新进展突出表现在应用范围上不断扩大，先后出现被动大陆边缘和前陆盆地的层序模式，至今又广泛应用于主动大陆边缘、裂谷体系等沉积盆地。在９０年代初，又用于现代沉积环境的对比研究，因而检验了层序模式和提高了对比精度。幕式沉积作用新观点的提出，冲击了所谓典型相模式的对比研究，大大提高了沉积体系研究的准确性和有利于层序界面的正确判别。始终是沉积学进展最为光辉一页的碳酸盐沉积，由于引入板块构造和诸多沉积作用新理论、新方法，对大区域乃至全球范围内的碳酸盐沉积体系的划分、控制因素和演化等方面，都有深入的认识和发现。还应用先进测试手段对石灰岩的微相和超相进行了与多种沉积条件联系的探索。已是主要储岩之一的砂岩成岩作用亦有重大的突破。对它的研究，从早期描述性单井页－砂岩整体成因研究，到８０年代后期进入按盆地成岩整体系统分析的研究阶段，而且对砂岩成岩作用中矿物学研究亦获得不少新认识。  相似文献   

6.
过程响应理论是在地球系统科学基础上提出的一种盆地沉积学研究方法,主要包括过程研究和响应研究两个方面,强调盆地演化过程对其沉积过程的控制意义。论文运用过程响应理论对辽河坳陷西部凹陷中北部地区Es4碳酸盐岩进行了研究,取得了很好的效果。研究表明,湖相碳酸盐岩的形成和分布在时间和空间上受湖盆演化过程控制明显,有利的地形和水动力条件、有利的气候和水介质条件、有利的物源和白云岩化条件,这三个关键要素,共同铸就了辽河坳陷西部凹陷中北部地区Es4湖相碳酸盐岩的沉积环境。运用过程响应理论,综合考虑碳酸盐岩沉积作用关键三要素,是建立更具指导作用和更具参考价值的湖相碳酸盐岩综合沉积模式的基础。  相似文献   

7.
Mesophotic reefs, hardgrounds and current-controlled pelagic to hemipelagic carbonates are facies marking carbonate platform drowning successions, irrespective of the factors controlling this evolution. A modern analogue of a carbonate platform in a state of drowning, where these facies occur has not been properly reported on to date. In the present study, the sedimentary environments of the Saya de Malha Bank are characterized using a multi-disciplinary approach including sedimentology, hydroacoustics, seismics and oceanography. The Saya de Malha Bank edifice with a surface of 40 808 km2 is located in the tropical Indian Ocean and lies in a water depth of 8 to 300 m extending from the surrounding more than 2000 m deep ocean floor, with no reef reaching the sea surface. Mesophotic coral and red algal facies co-exist with hemipelagic and bioclastic sands, together with a hardground. Ocean currents and internal waves are identified as major sedimentological controlling factors in the absence of elevated nutrient influx. Many features distributed along the present-day Saya de Malha Bank were described from studies presenting fossil examples of carbonate platform drowning. The results herein can therefore be applied to other drowning examples, in some cases allowing for more accurate interpretation of the stratigraphic record.  相似文献   

8.
The term ‘cap carbonate’ is commonly used to describe carbonate units associated with glacigenic deposits in Neoproterozoic successions. Attempts to use carbonate units as stratigraphic markers have been counfounded by inconsistent identification of ‘cap carbonates’ and a somewhat broad use of the term. Systematic sedimentological and geochemical analysis of carbonate rocks (mostly dolomite) associated with glacigenic deposits from the Neoproterozoic succession of the Kimberley region, north‐western Australia, shows that it is possible to characterize such units by their specific mineralogical, sedimentological, petrographic, geochemical and stratigraphic features. Hence, it is possible to differentiate true ‘cap carbonates’ from other carbonate units that are associated with glacigenic deposits. In the Kimberley successions two broad carbonate types are identified that reflect two stratigraphically distinct depositional realms. Carbonate rocks from the Egan Formation and Boonall Dolomite (the youngest carbonate units in the succession) are characterized by sedimentary components and features that are consistent with deposition on shallow platforms or shelves, analogous to Phanerozoic warm‐water carbonate platform deposits. In contrast, dolomite from the Walsh, Landrigan and Moonlight Valley Tillites preserves a suite of sedimentary and geochemical characteristics that are distinctly different from Phanerozoic‐like carbonate rocks; they are thin (ca 6 m), laterally persistent units of thinly laminated dolomicrite/dolomicrospar recording δ13C fluctuations from −1‰ to −5‰. These latter features are consistent with a ‘Marinoan‐style cap‐carbonate’ rock described from other Neoproterozoic successions. The similarity and broad distribution of these rocks in Australia, when considered within the context of genetic models suggesting a global oceanographic–atmospheric event, support their use as a lithostratigraphic marker horizon for the start of the Ediacaran Period at ca 635 Ma.  相似文献   

9.
Understanding how carbonate factories influence platform evolution is either based on qualitative conceptual models or quantitative numerical stratigraphic forward models. This study establishes new production depth profiles for four Cenozoic carbonate factories and uses two-dimensional stratigraphic forward models to explore how interactions between sediment production and transport within carbonate systems influence carbonate platform development. Newly established production/depth profiles are used to model photozoan and heterozoan carbonate grain associations, and the associated carbonate producing factories, and results are compared with well-studied outcrop successions. Sediment production from photozoan and heterozoan grain associations is also equalized, so that the total sediment production is the same but the depth/production profiles retain their distinctly different form. Thus, the effect of the different production profiles can be assessed. Ramps form when sediment diffusional transport rates are high relative to production rates and flat-top steep-margin platforms form when sediment diffusional transport rates are low relative to production rates, whether they are photozoan or heterozoan grain associations. The control exerted by sediment production and transport is expressed as a sediment transport–production ratio where transport ratio is a diffusional sediment transport in two-dimensions and production ratio is the total sediment production rate which is the product of a production profile that varies in depth and laterally. The transport–production ratio is a key control on the evolution and geometry of carbonate platforms. This is the case with different production profiles (both euphotic and oligophotic) and in mixed grain-size and mixed transport-rate systems. Carbonate producing factories significantly influence the rate of sediment production, the depth distribution of sediment production (production profiles), as well as the type of grain sizes produced (influencing resistance to erosion). Thus, different types of carbonate grain associations, and the associated carbonate producing factories, can produce the critical differences between carbonate platform geometries.  相似文献   

10.
ABSTRACT During the structural and sedimentological evolution of rifted continental margins in carbonate dominated settings, a characteristic stage is commonly reached when pelagic carbonate sedimentation occurs in association with complex fault block systems. An integrated study of the ammonite biostratigraphy and sedimentology of Jurassic pelagic rocks in the Umbria-Marche Apennines (central Italy) and in the Sila Mountains (north-east Calabria, southern Italy) has revealed three distinctive facies associations which can be related to specific structural and depositional settings. The condensed pelagic facies association is the constituent of condensed, usually discontinuous sequences, with numerous hiatal surfaces. The normal and resedimented pelagic facies association is typical of thicker sequences, comprising gravity flow and rockfall deposits. The composite pelagic facies association is one in which rockfall deposits are found associated with condensed sequences containing minor or no gravity flow deposits. Palaeotopographical highs are dominated by the condensed pelagic facies association and constitute the pelagic carbonate platform (PCP). Structurally, the PCP can be coincident with the top of a horst (or ‘central high’) block or the crestal area of a tilted block. In the latter case, the sediment surface of the PCP slopes gently (maximum of 1–3°) in this, the shallowest area of a pelagic carbonate ramp. PCPs can have erosional, bypass (rare) and depositional margins. Stepped margins also exist as subparallel rows of erosional and bypass margins. Trends from erosional to depositional margins are usually seen as a response to basin filling and burial of submarine tectonic escarpments by pelagic deposits in late synrift or early post-rift times. This is apparent from ‘progradation’ of PCP facies deposits beyond the structural boundaries of the PCP. Palaeoenvironmental analysis in pelagic carbonate platform deposits of the Umbria-Marche Apennines suggests that drowning of ancestral peritidal carbonate platforms in Pliensbachian time was followed first by a moderate deepening and then by shallowing in the Tithonian.  相似文献   

11.
Palaeontological deposits on Rusinga Island, Lake Victoria, Kenya, provide a rich record of floral and faunal evolution in the early Neogene of East Africa. Yet, despite a wealth of available fossil material, previous palaeoenvironmental reconstructions from Rusinga have resulted in widely divergent results, ranging from closed forest to open woodland environments. Presented here is a detailed study of the sedimentology and fauna of the early Miocene Hiwegi Formation at Waregi Hill on Rusinga Island, Kenya. New sedimentological analyses demonstrate that the Hiwegi Formation records an environmental transition from the bottom to the top of the formation. Lower in the Hiwegi Formation, satin-spar calcite after gypsum in siltstone deposits are interpreted as evidence for open hypersaline lakes. Moving up-section, carbonate deposits – interpreted previously as evidence of aridity – are actually diagenetic calcite cements, which preserve root systems of trees, suggesting a more closed environment; further up-section, the uppermost palaeosol layer contains abundant root traces and tree-stump casts, previously reported as evidence of a closed-canopy forest. These newly interpreted environmental differences are reflected by differences in faunal composition and abundance data from Hiwegi Formation fossil sites R1 and R3. Taken together, this work suggests that divergent palaeoenvironmental reconstructions in previous studies may have been informed by time-averaging across multiple environments. Further, results demonstrate that during the early Miocene local or regional habitat heterogeneity already existed. Rusinga’s Hiwegi Formation varied both spatially and temporally, which challenges the interpretation that a broad forested environment stretched across the African continent during the early Neogene, transitioning later to predominately open landscapes that characterize the region today. This result has important implications for interpretations of the selective pressures faced by early Miocene fauna, including Rusinga Island’s well-preserved fossil primates.  相似文献   

12.
Comparative sedimentology and palaeoecology of Oxfordian (Upper Jurassic) coral-dominated reefs of England, France, Italy and Switzerland has been used to: (1) identify and characterize different types of Late Jurassic coral reefs with regard to their litho- and biofacies; and (2) develop a depositional model for these reefs relating different reef types to each other within a palaeoenvironmental framework. Eight generic reef types and one associated reef facies are recognized. These are: (I) biostromal units dominated by platy microsolenids developed within clean limestone facies; (II) biostromal units dominated by platy microsolenids developed within marly facies; (III) reefal thickets dominated by tall dense phaceloid colonies developed within pure carbonate muds; (IV) microbial-coral reefs dominated by massive, branching ramose and phaceloid colonies; (V) large high diversity reefal units associated with large volumes of bioclastic material; (VI) small species-poor reefs developed within mixed carbonate/siliciclastic facies; (VII) microbial-coral reefs dominated by massive colonies; (VIII) reefal thickets dominated by branching ramose colonies with widely spaced branches developed amongst sand shoals and coral debris channels; and (IX) conglomerates rich in rounded coral fragments (the reef associated facies). The development of these different constructional and compositional reef types is interpreted as being primarily a function of light intensity, hydrodynamic energy levels and sediment balance. A conceptual depositional model based on these parameters can be used to predict the spatial and temporal distribution of different reefal carbonates and highlight sedimentological and palaeoecological trends in reef development.  相似文献   

13.
Trophic resources are an important control governing carbonate production. Though this importance has long been recognized, no calibration exists to quantitatively compare biogenic assemblages within trophic resource fields. This study presents a field calibration of carbonate producers in a range of settings against high‐resolution in situ measurements of nutrients, temperature and salinity. With its latitudinal extent from 30° to 23° N, the Gulf of California, Mexico, spans the warm‐temperate realm and encompasses nutrient regimes from oligo‐mesotrophic in the south to eutrophic in the north. Accordingly, from south to north carbonates are characterized by: (i) coral‐dominated shallow carbonate factories (5–20 m water depth) with average sea‐surface temperatures of 25 °C (min. 18 °C, max. 31 °C), average salinities of 35·06‰ and average chlorophyll a levels, which are a proxy for nutrients, of 0·25 mg Chl a m?3 (max. 0·48, min. 0·1). (ii) Red algal‐dominated subtidal to inner‐shelf carbonate formation (10–25 m) in the central Gulf of California exhibiting average temperatures of 23 °C (min. 18 °C, max. 30 °C), average salinities of 35·25‰, and average Chl a levels of 0·71 Chl a m?3 (max. 5·62, min. 0). (iii) Molluskan bryozoan‐rich inner to outer shelf factories in the northern Gulf of California (20–50 m) with average sea surface temperatures of only 20 °C (min. 13 °C, max 29 °C), average salinities of 35·01‰, and average contents of 2·2 mg Chl a m?3 (max. 8·38, min. 0). By calibrating sedimentological data with in situ measured oceanographic information in different environments, the response of carbonate producers to environmental parameters was established and extrapolated to carbonates on a global scale. The results demonstrate the importance of recognizing and quantifying trophic resources as a dominant control determining the biogenic composition and facies character of both modern and fossil carbonates.  相似文献   

14.
This virtual special issue represents a collection of papers concerning Crustal Melting selected by the Editor from those published on various aspects of this theme in the JMG since 1982. The papers are grouped into sequences that address topics that have been prominent in the JMG during the last 30 years concerning the origin, evolution and tectonic role of migmatites and migmatitic granulites in crustal evolution. These topics are: Open‐ and closed‐system processes in the formation of migmatites and migmatitic granulites; thermobarometry, P–T paths, phase equilibria modelling and retrograde processes in formerly melt‐bearing rocks; geochronology in partially melted rocks; and, microstructures, deformation and tectonics of melt bearing rocks. About one‐third of the papers published in the JMG since its inception concern the origin, evolution and tectonic significance of migmatites and migmatitic granulites in crustal evolution, including the first special issue published by the JMG concerning ‘Studies in the genesis and deformation of migmatites’ edited by Tracy & Day ( 1988; Volume 6, Issue 4, Pages 385‐543 ). Three subsequent Special Issues of the JMG include papers relevant to the theme of this virtual special issue; they are ‘Metamorphic processes: a celebration of the career contribution of Ron Vernon’, ‘Processes in granulite metamorphism’ and ‘Granulites, partial melting and the rheology of the lower crust’, edited by Brown & Clarke ( 2002; Volume 20, Issue 1, Pages 1‐213 ), Brown & White ( 2008; Volume 26, Issue 2, Pages 121‐299 ) and Brown et al. ( 2011; Volume 29, Issue 1, Pages 1‐166 ), respectively. The selection of papers in this virtual special issue is by no means comprehensive, but it is intended as a representative selection of what has been published in the JMG over 30 years to give the reader a broad overview of crustal melting. Furthermore, although many papers address more than one topic, each is included only once and has been placed within the most appropriate section.  相似文献   

15.
Maastrichtian orbitoidal foraminifera in Turkey show a variety of unusual features. They include remarkable specimens of their reproductive life cycle, lateral chambers within the embryo, teratological individuals (polyvalence), microboring activity within tests, equatorial chamber growth, and conical forms. These features provide evidence for Maastrichtian orbitoidal foraminiferal systematics, biological life cycle, palaeoecological conditions and fossilization. The growth of lateral and equatorial chambers is thought to have been controlled largely by genetic characteristics. Microboring activity is the result of their fossilization and life relationships with other micro-organisms such as Talpinella conicularia. Conical forms and polyvalence are thought to be related to sedimentological characteristics of the palaeoenvironment, such as currents. Abnormal growth of the equatorial chambers is accepted as one of the main distinguishing features of Orbitoides gruenbachensis.  相似文献   

16.
Although general trends in transgressive to highstand sedimentary evolution of river‐mouth coastlines are well‐known, the details of the turnaround from retrogradational (typically estuarine) to aggradational–progradational (typically coastal/deltaic) stacking patterns are not fully resolved. This paper examines the middle to late Holocene eustatic highstand succession of the Po Delta: its stratigraphic architecture records a complex pattern of delta outbuilding and coastal progradation that followed eustatic stabilization, since around 7·7 cal kyr bp . Sedimentological, palaeoecological (benthic foraminifera, ostracods and molluscs) and compositional criteria were used to characterize depositional conditions and sediment‐dispersal pathways within a radiocarbon‐dated chronological framework. A three‐stage progradation history was reconstructed. First, as soon as eustasy stabilized (7·7 to 7·0 cal kyr bp ), rapid bay‐head delta progradation (ca 5 m year?1), fed mostly by the Po River, took place in a mixed, freshwater and brackish estuarine environment. Second, a dominantly aggradational parasequence set of beach‐barrier deposits in the lower highstand systems tract (7·0 to 2·0 cal kyr bp ) records the development of a shallow, wave‐dominated coastal system fed alongshore, with elongated, modestly crescent beaches (ca 2·5 m year?1). Third, in the last 2000 years, the development of faster accreting and more rapidly prograding (up to ca 15 m year?1) Po delta lobes occurred into 30 m deep waters (upper highstand systems tract). This study documents the close correspondence of sediment character with stratal distribution patterns within the highstand systems tract. Remarkable changes in sediment characteristics, palaeoenvironments and direction of sediment transport occur across a surface named the ‘A–P surface’. This surface demarcates a major shift from dominantly aggradational (lower highstand systems tract) to fully progradational (upper highstand systems tract) parasequence stacking. In the Po system, this surface also reflects evolution from a wave‐dominated to river‐dominated deltaic system. Identifying the A–P surface through detailed palaeoecological and compositional data can help guide interpretation of highstand systems tracts in the rock record, especially where facies assemblages and their characteristic geometries are difficult to discern from physical sedimentary structures alone.  相似文献   

17.
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18.
碳酸盐岩具有广泛的时空分布,主要为生物成因,而该生物成因属性注定了其与海洋生物、海洋化学条件等密切相关。海相碳酸盐岩沉积相模式对于描述、表征和解释碳酸盐岩地层结构成因具有重要的指导意义。本文回顾了近70年来碳酸盐岩沉积相模式从二维水体能量模型到三维地形模型的发展变化。如何深入分析不同形态特征和内部构成的碳酸盐岩台地的成因机制,解读其相应的地球生物-环境演化信息,是当前和下一步需要努力的方向。为此本文介绍了碳酸盐工厂和碳酸盐岩台地成因方面的研究进展,强调了碳酸盐岩地层的时代特殊性,并以滇黔桂地区为例,从碳酸盐工厂分析的角度剖析了该区二叠纪吴家坪期碳酸盐岩沉积学研究现状,展望了下一步的研究方向,旨在引起同行重新认识生物和海洋环境条件在碳酸盐岩台地演化中的作用,重视全球空间尺度范围内同时代碳酸盐岩的相似性与差异,并从古生态角度入手开展碳酸盐工厂分析,发掘碳酸盐岩台地的生物学和海洋学意义。  相似文献   

19.
The sub‐fossil head capsules of larval Chironomidae have been widely exploited as palaeoecological indicators of lentic ecosystems but their value in the interpretation of the evolution of lotic systems has been underutilised by comparison. Recent research has demonstrated that the remains of Chironomidae are abundant within fluvial sequences and that they offer a valuable record of channel change and floodplain evolution that may complement that derived from existing biological and sedimentological techniques. This paper demonstrates the use of Chironomidae in characterising the palaeoflow regime of a large mid–late Holocene floodplain palaeochannel (5470–4960 to 1530–1350 cal. a BP) of the River Trent (Derbyshire, UK). Using expert knowledge and published information regarding flow preferences, larval Chironomidae were incorporated into the PalaeoLIFE (Lotic‐invertebrate Index for Flow Evaluation) methodology. The results clearly demonstrate that the sub‐fossil record provided by Chironomidae can be used to characterise changes in the flow regime within palaeochannel sections. At the scale of the channel section, species‐ and generic‐level ecological associations can provide useful information regarding habitat characteristics, including the presence of instream vegetation, mineral substrates and woody debris. The ability to undertake environmental reconstruction and channel evolution history was significantly enhanced through the application of a multi‐proxy approach, by incorporating other aquatic insect groups (Trichoptera and Coleoptera) into the PalaeoLIFE metric, together with sedimentological data. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

20.
The classical Middle to Upper Triassic carbonate sections at Monte Santa Giusta and Punta del Lavatoio, North‐west Sardinia (Italy), referred to the Muschelkalk and Keuper lithofacies group, are revisited and their trace fossil content is investigated for the first time. A combined ichnological and sedimentological study reveals insights into the depositional environments, regional context, palaeogeography and sequence stratigraphy. The results indicate deposition on a homoclinal carbonate ramp with broad facies belts. All recognized trace fossils are also known from time‐equivalent deposits of Germany and thus indicate a close affinity between the North‐west Sardinian Triassic and the Germanic Basin. Only a few trace fossils are particularly abundant and these indicate opportunistic colonization by their producers, which is probably related to restricted endobenthic conditions due to reduced oxygen and/or increased salinity. The trace fossil association can be grouped into a softground suite belonging to the Cruziana ichnofacies, and a firmground suite of the Glossifungites ichnofacies. This discrimination enables an interpretation of the northern Monte Santa Giusta section as a carbonate ramp with extensive tidal flats and abundant carbonate accumulation in a relatively proximal position, whereas the southern Punta del Lavatoio section exhibits broad lagoonal environments with reduced sedimentation in a deeper and more Tethys‐influenced area. The Sardinian sections are ichnologically similar to the Anisian–Ladinian succession known from the Tatra Mountains, but differ from it by having a slightly higher ichnodiversity, which again can be attributed to a less restricted lagoonal environment. This study demonstrates the importance of integrating trace fossil analysis in sedimentological and palaeontological investigations of carbonate systems.  相似文献   

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