塔里木盆地晚泥盆世东河塘组河口湾相遗迹化石

河口湾具有特定的环境条件和沉积组成,其遗迹化石具有半咸水沉积的遗迹群落特征。描述和分析塔里木盆地塔中4井区上泥盆统东河塘组河口湾沉积中的遗迹化石和生物扰动构造后,发现3类遗迹组构,其中Ophiomorpha遗迹组构发育在纯净砂岩中,与河口湾潮汐砂坝有关;Skolithos遗迹组构发育在薄层砂岩中,与河口湾砂坪有关;Palaeophycus遗迹组构发育在泥岩中,与河口湾泥坪、砂泥坪有关。     

塔里木盆地下志留统遗迹组构及其环境解释

遗迹组构是由生物成因改造的沉积岩组构,是物理过程和生物过程相互作用的产物,文中运用生物扰动指数和遗迹组构组分图解综合分析方法在塔里木盆地下志留统塔塔埃尔塔格组中建立４个遗迹组构,即反映下临滨和滨外环境的Ｈelminthopsis-Diplocraterion复合遗迹组构,反映了下临滨环境的Ｐalaeophycus遗迹组构和Ｓkolihos遗迹组构,反映中上临滨环境的Ｓkolithos-Arenicolites遗迹组构,对遗迹化石和生物扰动构造进行阶层分析,从中识别出受固底质控制的遗迹化石Ｄiplocraterion,常代表层序地层学中的重要界面。     

河南西峡盆地上白垩统寺沟组遗迹化石及其沉积环境

西峡盆地上白垩统寺沟组岩性以紫红色薄层粉砂质泥岩、灰黄—灰绿色厚层状粉砂岩、细砂岩为主,夹灰黄、灰白色厚层状含砾砂岩及中粗砂岩。本次工作发现遗迹化石11属19种:包括Archaeonassaisp.,Arenicolites isp.,Cylindricumisp.,Beaconites antarcticus,B.capronus,B.coronus,Gastruichnus xixiaensis,Naktodemasis isp.,Palaeophycus tubularis,P.heberti,P.sulcatus,P.striatus,Planolites beverleyensis,Planolitesisp.,Scoyenia gracilis,Skolithos verticalis,Skolithos isp,Taenidium irregularis,T.serpentinum和似逃逸迹。根据遗迹化石的产状及其围岩的沉积特征,建立了Beaconites-Palaeophycus遗迹组合和Taenidium-Scoyenia遗迹组合,分别代表了曲流河和浅水湖泊(河漫湖泊)沉积环境中遗迹化石的组成特征。基于岩性特征、沉积构造和遗迹化石组成特征的综合分析,划分出五种沉积序列类型,揭示了寺沟组曲流河边滩、泛滥平原、洪流砂体与河漫湖泊在沉积过程中的变化和相应的遗迹群落变化特征。结合寺沟组中遗迹化石分布及组合特征,Beaconites-Palaeophycus遗迹组合和Taenidium-Scoyenia遗迹组合可归属于Scoyenia遗迹相。     

贵州台江早、中寒武世凯里组的遗迹化石新发现*

最近在凯里组中发现了新的遗迹化石 9属 ,其中大多数分子属Cruziana遗迹相 ,重要的遗迹属有 :Tasmanadia ,Bostricophyton ,Monomorphichnus,Oldhamia ,Phycodes ,Chon-drites,Treptichnus等。在产凯里化石群的层位中发现有大量的韵律层 ,韵律层中的遗迹化石具有分层性 ,反映不同的水动力环境。遗迹组合与Seilacher(1975)描述的早寒武世遗迹化石组合相似 ,推测凯里化石的埋藏环境为陆棚环境。     

辽宁省葫芦岛地区寒武纪遗迹化石及其古生态意义北大核心CSCD

在辽宁省葫芦岛地区的寒武系中发现了由Treptichnus pedum,Planolites montanus和Palaeophycus heberti构成的遗迹化石组合。Treptichnus pedum分布于馒头组上部石英细砂岩中,其特征符合曳鳃动物的摄食遗迹,说明曳鳃动物是当时这一地区底栖宏体动物群落的主要组成部分。结合该群落在整个华北地台广泛出现于馒头组上部的情况,其兴起可能是一次区域性底栖环境良化事件的结果。Planolites montanus和Palaeophycus heberti出现在张夏组上部中、薄层灰岩中,位于剖面上最早出现的一层风暴沉积和一中厚层叠层石之间,表明其形成时海盆水循环较好,水动力较强,底层水和底质氧气较为充足,适宜底栖生物的生存。     

遗迹化石Chondrites的指相意义和阶层分布

介绍和评述Chondrites的基本特征和流行的成因解释 ,记述最近发现于美国犹他州中西部北美下 中奥陶统之交层型剖面上的Chondrites遗迹组构的不寻常特征和属性 :细小的Chondrites被所有与之共生的遗迹化石交切 ,形成于水与沉积物界面附近缺氧的早期软底质中 ,Chondrites是形成最早和最浅的遗迹阶层。流行的遗迹相和遗迹阶层模式的不足是 :前者在操作上 ,简单地将遗迹化石及其组合处理为同沉积或准同沉积的物理沉积构造 ,忽略了造迹活动的多阶段和多阶层的特点 ;后者的资料基础仅依据中生代以来的地层记录 ,对重大生物 环境事件和造迹生物生态习性演化对遗迹阶层形成和分布的影响注重不够。指出Chondrites的阶层分布和对古氧相的示踪在古生代与中生代有重要差别     

辽宁省葫芦岛地区寒武纪遗迹化石及其古生态意义

在辽宁省葫芦岛地区的寒武系中发现了由Treptichnus pedum,Planolites montanus和Palaeophycus heberti构成的遗迹化石组合。Treptichnus pedum分布于馒头组上部石英细砂岩中,其特征符合曳鳃动物的摄食遗迹,说明曳鳃动物是当时这一地区底栖宏体动物群落的主要组成部分。结合该群落在整个华北地台广泛出现于馒头组上部的情况,其兴起可能是一次区域性底栖环境良化事件的结果。Planolites montanus和Palaeophycus heberti出现在张夏组上部中、薄层灰岩中,位于剖面上最早出现的一层风暴沉积和一中厚层叠层石之间,表明其形成时海盆水循环较好,水动力较强,底层水和底质氧气较为充足,适宜底栖生物的生存。     

川中-川南地区上三叠统滨浅湖沉积中的遗迹化石

川中-川南地区上三叠统滨浅湖沉积中产有丰富的动物遗迹化石,识别为3大类6属8种,包括Sko-lithos linearis,S.verticalis,Ophiomorpha nodosa,Planolites beverleyensis,P.montanus,Palaeophycus tubularis,Taenidiumsatanassi和Cochlichnus anguineus,另外,逃逸构造也很发育。这些遗迹化石主要是无脊椎动物的居住迹、进食迹和觅食迹,大多为全浮痕和上浮痕保存。根据遗迹化石的组合特征及其沉积环境,可识别出3个遗迹组合:1)Skolithos linearis遗迹组合,主要由长的垂直或高角度倾斜的悬食居住潜穴构成,反映高能的砂质滨湖环境;2)Cochlichnus-Planolites遗迹组合,主要由进食迹和牧食迹组成,形成于低能的滨湖沼泽环境;3)Skolithos-Planol-ites遗迹组合,以居住潜穴和进食潜穴为主,遗迹化石的丰度较高,代表潮湿气候条件下的浅湖环境。根据生物扰动的分布及扰动强度,浅湖中可识别出两类扰动类型,即1)砂泥边界扰动,扰动主要发育于砂泥交界处,代表了浅湖下部环境;2)薄砂层扰动,扰动主要发育于薄砂层中,主要出现于浅湖中下部沉积中。     

新疆北部泥盆系遗迹化石的拓扑遗迹学研究

以遗迹化石的形成、保存、变形的地质学特征和遗迹生物的内在生物学属性为基础，从欧氏几何学与拓扑学的结合上，记述了新疆北部泥盆纪火山沉积岩系中２９个遗迹属的分类、命名体系，共生组合关系，遗迹群落，拓扑特征及其古生态、古环境和层序地层意义。新建立了１３个拓扑遗迹属，１５种遗迹化石共生组合关系。根据遗迹化石的层深分布，识别出表层、浅层、深层和混层遗迹群落。     

华北板块南部寒武系底部辛集组遗迹化石及其时代意义

首次详细描述了河南省石门沟、阳坡和山西省水峪等3条剖面寒武系底部辛集组中的遗迹化石。遗迹化石主要产出于辛集组的近底部层位,以水平管状遗迹化石为主,共计8遗迹属,12遗迹种(含3个未定种),包括Arenicolites sp.,Didymaulichnus lyelli,Gordia marina,Helminthopsis abeli,Helminthopsis sp.,Palaeophycus striatus,Palaeophycus tubularis,Phycodes sp.,Planolites beverleyensis,Planolites montanus,Treptichnus pedum与Treptichnus pollardi,此外还有2枚属种未定的遗迹化石。这一遗迹化石组合属非典型的Cruziana遗迹相,形成于盐度正常的潮下带砂质软底环境。通过对寒武纪早期管状遗迹化石Palaeophycus与Planolites直径大小的统计与分析,推测辛集组下部地层的时代不早于沧浪铺期。     

An integrative ichnological and taphonomic approach in a transgressive–regressive cycle: a case study from Devonian of Paraná Basin,Brazil

The palaeoenvironmental context of a section of the Devonian Ponta Grossa Formation (Paraná Basin) was examined using an integrated ichnological and taphonomic approach. Three taphofacies (T‐A, T‐B and T‐C) and six ichnofabrics are recognized. T‐A is mainly composed of disarticulated organisms and is associated with Chondrites, Planolites‐Palaeophycus, Asterosoma‐Zoophycos and Asterosoma‐Chondrites ichnofabrics, representing the Cruziana ichnofacies. The upward increase in diversity and abundance of body fossils for Taphofacies A can be explained by changes in sedimentation rates during aggradational to progradational phases. T‐B beds, represented by articulated brachiopods, occur in distal tempestites associated with the Skolithos ichnofabric (Skolithos ichnofacies) and represent higher hydrodynamic energy and oxygenation than in T‐A. Taphofacies C, characterized by a mix of articulated and disarticulated organisms, generally lacks bioturbation except for Chondrites ichnofabrics occurring only at the bed tops, suggesting low substrate oxygenation and low‐energy conditions. T‐C indicates the maximum transgression in the T‐R cycle, characterizing it as a good indicator of maximum flooding surfaces. The composite Asterosoma‐Teichichnus ichnofabric (bioturbation degree 5) occurs in layers without body fossils and represents suites of the Cruziana ichnofacies. This likely reflects intense intrastratal activity at all substrate levels, which facilitated the oxygenation of the substrate disallowing the preservation of organism remains. This observation indicates that the bioturbation is an important factor controlling the loss of taphonomic information within the TAZ, mainly when associated with detritus‐feeding trace fossils.     

山东莱阳盆地早白垩世莱阳群的遗迹化石

山东莱阳早白垩阳群自下而上分为瓦屋夼组,林寺山组,止风庄组,水南组,龙旺庄组和曲格庄组。为一套河湖相沉积,产有较丰富,分异度较高的非海相遗迹化石和兽脚类恐龙足迹化石,共鉴定出遗迹属11个,未定属1个,其中遗迹种9个,未定种2个,遗迹化石是：Cochlichnus anguines,Diplocraterion parallelun,Helminthoidichnites tenuis,Palaeophycus tubularis,Planolites montanus ,Scolica sp.,Scoyenia gracilis,Skolithos linearis,Taenidium cameromensis,Thalassinoides sp.,恐龙足迹化石是：Paragrallator yangi,这些化石按习性可分为4类,即：居住构造, 爬行迹,觅食[迹和牧食迹,其中又以前3种为主,遗迹化石在剖面上的分布不均匀,以上部的水南组,龙旺庄,曲格庄3个组最丰富。     

湖南新化下石炭统遗迹化石及其沉积环境

鉴定了产自湖南新化地区早石炭世碳酸岩沉积中的遗迹化石6属(Zoophycus, Chondrites, Phycodes, Planolites, Palaeophycus, Skolithos)16种.并根据岩性实体与遗迹化石以及沉积构造等特征,划分为2个沉积亚相、21个微相、19个遗迹相.     

天山和昆仑—秦岭造山带志留系、石炭系和三叠系复理石相遗迹化石

在天山志留系,石炭系和东昆仑－西秦岭三叠系浊积岩系中遗迹化石发育,经研究计有：Helminthopsis hieroglyphica,Neonerietes biserialis.,N,uniserialis,palaeophycus isp.,P.serratus,P.striatus.P.tubularis,Paleodictyon imperfectum,Phycodes circinnatum,Phycosiphon incertum,Planolites annularis,P.beverleyensis,P.Montanus,Rhizocorallium ips.,Scalarituba missourensis,Skolithos ips.,?Spirorhaphe isp.,sublorenzinia ips.Tambia isp.,Taphrhelminthopsis auricularis,Teichichnus isp.,Thalassinoides isp.它们构成4种遗迹化石组合：Phycosiphon-Palaeophycus组合,Neonereites-Scalarituba组合,Paleodictyon组合和Phycodes Skolithos组合,分别代表局限缺氧深海盆地浊流沉积,半深海环境中－上扇沉积,多岛洋环境的中－下扇沉积,半深海环境的中扇浊流沉积。     

河南泌阳凹陷古近纪核桃园组遗迹化石组合及其环境意义——兼论深水湖泊遗迹相特征

南襄盆地泌阳凹陷古近纪核桃园组湖泊沉积中发育大量遗迹化石,含5个遗迹组合,形成于从滨湖到深湖的不同沉积环境中。Taenidiumserpentinum遗迹组合反映稍有覆水并周期性暴露的低能滨湖环境;Skolithos linearis遗迹组合代表湖泊中上临滨环境;Planolites montanus遗迹组合与低能浅湖环境有关;Skolithos verticalis遗迹组合形成于浅湖的远源风暴沉积中;Semirotundichnus dongyingensis遗迹组合发育在贫氧的半深湖-深湖沉积环境中。     

Trace fossils in middle to late triassic fluvial redbeds,pranhita‐godavari valley,south India

Several morphological varieties of trace fossils abound in Middle and Late Triassic fluvial redbeds in the Pranhita‐Godavari Valley, south India, including Skolithos, Palaeophycus, Taenidium, escape burrows, and a type of trace very similar to ‘small stuffed burrows’ from the Triassic of Greenland. Burrow morphology was influenced by local hydrodynamic conditions. The distribution of burrows was facies controlled; some forms are restricted to channel deposits whereas others occur only in floodplains. Vertical dwelling burrows (Skolithos) occur in both channel and floodplain deposits. Horizontal structures representing deposit feeding (Taenidium) are confined to nondepositional surfaces within parallel‐laminated sandstones having parting lineations that represent catastrophically emplaced sand‐sheets in channels and proximal floodplains. Vertical escape burrows are confined to what were slowly but continually accreting parallel‐laminated sands of channel bars. Horizontal dwelling burrows (Palaeophycus) and ‘small stuffed burrows’ are virtually restricted to the smaller sandsheets of floodplain drainage systems.

The burrow assemblages do not occur as recurrent associations throughout the redbed sequence, and variations in different stratigraphic levels seem to be controlled by minor differences within a broadly similar environment. The entire assemblage has components of both the Scoyenia and Rusophycus ichnocoenoses reported from East Greenland but may be considered as the Scoyenia ichnofacies characteristic of redbeds deposited in extensive floodplains dissected by small streams, even though no Scoyenia individuals are present.     

北京昌平青白口系痕迹化石

北京昌平青白口系长龙山组和景儿峪组发育有丰富的痕迹化石,其中长龙山组产有Ｈｅｌｍｉｎｔｈｏｐｓｉｓ ｓｐ．,Ｃｏｃｈｌｉｃｈｎｕｓ ｓｐ．,代表潮下低能环境;景儿峪组产有Ｓｋｏｌｉｔｈｏｓ ｓｐ．和Ｍｏｎｏｃｒａｔｅｒｉｏｎ ｓｐ．,代表高能潮间环境。     

Oceanic Anoxic Event at the Cenomanian–Turonian boundary interval (OAE-2): ichnological approach from the Betic Cordillera, southern Spain

Ichnological analysis of dark sediments of the Oceanic Anoxic Event at the Cenomanian–Turonian boundary interval (OAE-2) from the Betic Cordillera, southern Spain, reveals the presence of ichnofabrics containing trace fossils Chondrites isp., Palaeophycus heberti , Planolites isp., Thalassinoides isp., Trichichnus linearis , Zoophycos isp., and other bioturbational structures. Analysis of the ichnofabrics and trace fossil diversity allowed the reconstruction of relative oxygenation. Before the OAE-2, oxygenation of sediments was generally good, but it was punctuated by short anoxic events. During the OAE-2i, several longer anoxic intervals were interrupted by shorter dysaerobic and oxic periods. After the OAE-2, oxygenation improved and almost all trace fossils known before OAE-2 reappeared, although oxygenation dropped a few times to anoxia. Generally, the short oxygenation changes reveal a periodicity, which may suggest a Milankovitch control.