New data on Upper Kimmeridgian-Tithonian biostratigraphy and ammonites of the eastern Crimea

Based on ammonites, Upper Kimmeridgian sediments are first established in the Crimean Mountains. The Kimmeridgian-Tithonian boundary recognizable in a continuous section is placed inside the Dvuyakomaya Formation of uniform largely clayey sediments. Assemblages of Kimmeridgian ammonites Lingulaticeras cf. procurvum (Ziegler), Pseudowaagenia gemmellariana Oloriz, Euvirgalithacoceras cf. tantalus (Herbich), Subplanites sp.) and Tithonian forms (?Lingulaticeras efimovi (Rogov), Phylloceras consaguineum Gemmellaro, Oloriziceras cf. schneidi Tavera, and Paraulacosphinctes cf. transitorius (Oppel) are described. A new biostratigraphic scheme proposed for the upper Tithonian-Berriasian of the Crimean Mountains includes the following new biostratigraphic units: the Euvirgalithacoceras cf. tantalus Beds of the upper Kimmeridgian, ?Lingulaticeras efimovi Beds of the lower Tithonian, and Oloriziceras cf. schneidi and Paraulacosphinctes cf. transitorius beds of the upper Tithonian. The middle Tithonian is proposed to consist of the fallauxi and semiforme (presumably) zones. The ammonities found determine the early Kimmeridgian-Berriasian age of the Dvuyakornaya Formation that is most likely in tectonic contact with the underlying Khutoran Formation.     

Biostratigraphy of Jurassic-Cretaceous boundary sediments in the Eastern Crimea

The Dvuyakornaya Formation section in the eastern Crimea is described and subdivided into biostratigraphic units based on ammonites, foraminifers, and ostracodes. The lower part of the formation contains first discovered ammonites of the upper Kimmeridgian (Lingulaticears cf. procurvum (Ziegler), Pseudowaagenia gemmellariana Olóriz, Euvirgalithacoceras cf. tantalus (Herbich), Subplanites sp.) and Tithonian (?(Lingulaticeras efimovi (Rogov), Phylloceras consaguineum Gemmellaro, Oloriziceras cf. schneidi Tavera, and Paraulacosphinctes cf. transitorius (Oppel)). Based on the assemblage of characteristic ammonite species, the upper part of the formation is attributed to the Berriasian Jacobi Zone. Five biostratigraphic units (zones and beds with fauna) distinguished based on foraminifers are the Epistomina ventriosa-Melathrokerion eospirialis Beds and Anchispirocyclina lusitanica-Melathrokerion spirialis Zone in the upper Kimmeridgian-Tithonian, the Protopeneroplis ultragranulatus-Siphoninella antiqua, Frondicularia cuspidiata-Saracenaria inflanta zones, and Textularia crimica Beds in the Berriasian. The Cyrherelloidea tortuosa-Palaeocytheridea grossi Beds of the Upper Jurassic and Raymoorea peculiaris-Eucytherura ardescae-Protocythere revili Beds of the Berriasian are defined based on ostracodes. A new biostratigraphic scale is proposed for the upper Kimmeridgian-Berriasian of the eastern Crimea. The Dvyyakornaya Formation sediments are considered as deepwater facies accumulated on the continental slope.     

The bivalve Anopaea (Inoceramidae) from the Upper Jurassic–lowermost Cretaceous of Mexico

In Mexico, the Upper Jurassic to lowermost Cretaceous La Casita and coeval La Caja and La Pimienta formations are well-known for their abundant and well-preserved marine vertebrates and invertebrates. The latter include conspicuous inoceramid bivalves of the genus Anopaea not formally described previously from Mexico. Anopaea bassei (Lecolle de Cantú, 1967), Anopaea cf. stoliczkai (Holdhaus, 1913), Anopaea cf. callistoensis Crame and Kelly, 1995 and Anopaea sp. are rare constituents in distinctive Tithonian–lower Berriasian levels of the La Caja Formation and one Tithonian horizon of the La Pimienta Formation. Anopaea bassei was previously documented from the Tithonian of central Mexico and Cuba, while most other members of Anopaea described here are only known from southern high latitudes. The Mexican assemblage also includes taxa which closely resemble Anopaea stoliczkai from the Tithonian of India, Indonesia and the Antarctic Peninsula, and Anopaea callistoensis from the late Tithonian to ?early Berriasian of the Antarctic Peninsula. Our new data expand the palaeogeographical distribution of the high latitude Anopaea to the Gulf of Mexico region and substantiate faunal exchange, in the Late Jurassic–earliest Cretaceous, between Mexico and the Antarctic Realm.     

Ichnofabric analysis of the Tithonian shallow marine sediments (Bhadasar Formation) Jaisalmer Basin,India

The shallow marine sedimentary sequence of the Jaisalmer Basin exhibits one of the important and well-developed Tithonian sedimentary outcrops for western India. The ichnology and ichnofabric of the lower part of Bhadasar Formation (i.e., Kolar Dongar Member) belonging to Tithonian age are presented and discussed. The Kolar Dongar Member represents a shallow marine succession that contains 16 ichnotaxa: Ancorichnus ancorichnus, Conichnus conicus, Gyrochorte comosa, cf. Jamesonichnites heinbergi, Imponoglyphus kevadiensis, Laevicyclus mongraensis, Monocraterion tentaculatum, Ophiomorpha nodosa, Palaeophycus tubularis, P. bolbiterminus, Phycodes palmatus, Planolites beverleyensis, Rhizocorallium isp., Rosselia rotatus, R. socialis, and Teichichnus rectus. The ichnofabric analysis divulges five distinct ichnofabrics, each typifying distinct depositional environment within shallow marine conditions. The ichnofabric Ophiomorpha 1 with syn-sedimentary faulting exemplifies high energy conditions typical of lower shoreface environment, whereas the Ophiomorpha 2 ichnofabric typifies upper shoreface environment. The Ancorichnus ichnofabric reflects lower offshore condition of deposition. The high ichnodiversity Ancorichnus–Rosselia ichnofabric is indicative of inner shelf conditions, while low ichno-diversity Teichichnus ichnofabric indicates prevalence of low energy brackish bay environment. Thus, Tithonian Kolar Dongar Member indicates depositional environment ranging from shoreface to offshore to inner shelf and finally to brackish bay environment.     

Stratigraphy and Depositional Conditions of the Tithonian(?)–Berriasian Deposits in the Tonas River Region (Central Crimea)

Lithology and Mineral Resources - The composition and depositional environments of the Tithonian(?)–Berriasian deposits in the Tonas River basin (Central Crimea) are considered. The paper...     

The ammonite family Parahoplitidae in the Sanganeh Formation of the Kopet Dagh Basin, north-eastern Iran

The Iranian part of the Kopet Dagh Basin is located in north-eastern Iran, where sedimentation was continuous throughout Jurassic to Tertiary times. The ammonite content of the Sanganeh Formation (Lower Cretaceous) has been studied. The following parahoplitid forms have been recorded: Acanthohoplites cf. aschiltaensis, A. cf. bigoureti, A. sp. 1, A. sp. 2, A. spp., Colombiceras sp., Hypacanthoplites cf. anglicus, H. cf. clavatus, H. cf. elegans, H. cf. subrectangulatus, H. uhligi, H. sp., Parahoplites cf. campichii and P. cf. maximus.     

Microbial mats implicated in the generation of intrastratal shrinkage (‘synaeresis’) cracks

Intrastratal shrinkage (often termed ‘synaeresis’) cracks are commonly employed as diagnostic environmental indicators for ancient salinity‐stressed, transitional fluvial‐marine or marginal‐marine depositional environments. Despite their abundance and use in facies interpretations, the mechanism of synaeresis crack formation remains controversial, and widely accepted explanations for their formation have hitherto been lacking. Sedimentological, ichnological, petrographic and geochemical study of shallow marine mudstone beds from the Ordovician Beach Formation of Bell Island, Newfoundland, has revealed that crack development (cf. synaeresis cracks) on the upper surface of mudstone beds is correlated with specific organic, geochemical and sedimentological parameters. Contorted, sinuous, sand‐filled cracks are common at contacts between unbioturbated mudstone and overlying sandstone beds. Cracks are absent in highly bioturbated mudstone, and are considered to pre‐date firmground assemblages of trace fossils that include Planolites and Trichophycus. The tops of cracked mudstone beds contain up to 2·1 wt% total organic carbon, relative to underlying mudstone beds that contain around 0·5 wt% total organic carbon. High‐resolution carbon isotope analyses reveal low δ¹³C_org values (?27·6‰) on bed tops compared with sandy intervals lacking cracks (?24·4 to ?24·9‰). Cracked mudstone facies show evidence for microbial matgrounds, including microbially induced sedimentary structures on bedding planes and carbonaceous laminae and tubular carbonaceous microfossils in thin section. Non‐cracked mudstone lacks evidence for development of microbial mats. Microbial mat development is proposed as an important prerequisite for intrastratal shrinkage crack formation. Both microbial mats and intrastratal shrinkage cracks have broad palaeoenvironmental distributions in the Precambrian and early Phanerozoic. In later Phanerozoic strata, matgrounds are restricted to depositional environments that are inhospitable to burrowing and surface‐grazing macrofauna. Unless evidence of synaeresis (i.e. contraction of clay mineral lattices in response to salinity change) can be independently demonstrated, the general term ‘intrastratal shrinkage crack’ is proposed to describe sinuous and tapering cracks in mudstone beds.     

DAS KALZITGEFÜGE DER SPARITISCHEN KALKE DES PLASSEN (TITHONIUM, NÖRDLICHE KALKALPEN, OBERÖSTERREICH)

The sparitic Plassen Limestone (Tithonian, N.K.A., Upper Austria) The sparitic Plassen Limestone (Tithonian, N.K.A., Upper Austria) shows various types of calcite-fabric. We distinguish fibrous, fibrous-drusy, and drusy cavity fillings. While the fibrous fabric can be interpreted as submarine precipitation soon after sedimentation, an explanation of the drusy calcites as submarine or subaerial precipitation remains an open question. There are, however, indications of subaerial influences. For the origin of the dismicrites an interpretation as shrinkage structures may be considered.     

Upper Callovian-Middle Oxfordian belemnite assemblage from Jara Dome,Western Kachchh

Belemnites and ammonites were collected from the Dhosa Oolite beds of Jara Dome in Kachchh. The Dhosa Oolite is an important marker of the Mesozoic sediments exposed in the Kachchh Basin. Nine belemnite species are reported belonging to four genera Belemnopsis, Demubelus, Hibolithes and Conodicoelites. These include Belemnopsis cf. moluccana Boehm, B. calloviensis Oppel, Demubelus weberi Stolley, Hibolithes boloides Stolley, H. longiscissus Stolley, H. cf. compressus Stolley, H. jumarensis Waagen, H. budhaichus Stoliczka and Conodicoelites cf. abadi Challinor. Besides the belemnites, diagnostic ammonoid fauna are also recorded from the studied section enabling better controlled stratigraphic resolution and biostratigraphic correlation. Taxonomic studies on the different belemnite species are presented with illustration for reference.     

Permo-Carboniferous Radiolarians from the Wupata＇erkan Group, Western South Tianshan, Xinjiang, China

The Wupata‘erkan Group, also called Wupata‘erkan Formation, distributed in the South Tianshan, Xinjiang,China, mainly consists of gray and dark gray fine-grained clastic rocks, interlayered with volcanic rocks, carbonates and cherts. Some ultra-basic rocks (blocks) punctuate the formation. The formation was variously assigned to Silurian-Middle Devonian, Silurian-Lower Devonian, and pre-Devonian, mainly based on Atrypa bodini Mansuy, Hypothyridina parallelepipedia (Brour.) and Prismatophyllum hexagonum Yoh collected from the limestone interlayers, respectively.However, radiolarian fossils obtained from 24 chert specimens of the Wupata‘erkan Group, mainly include Albaillella sp.cf. A. undulata Deflandre, Albaillella sp. cf. A. paradoxa Deflandre, Albaillella cf. A. deflandrei Gourmelon, Albaillella sp. cf. A. indensis Won, Albaillella sp. cf. A. excelsa Ishiga, Kito and Imoto, Albaillella sp. and Latentifistulidae gen. et. sp.indet., are earliest Carboniferous and Late Permian. The earliest Carboniferous assemblage is characterized by Albaillella sp. cf. A. undulata Deflandre, Albaillella sp. cf. A. paradoxa Deflandre, Albaillella cf. A. deflandrei Gourmelon and Albaillella sp. cf. A. indensis Won, and the Late Permian assemblage by Albaillella sp. cf. A. excelsa Ishiga, Kito and Imoto. This new stratigraphic evidence indicates that the Wupata‘erkan Group is possibly composed of rocks with different ages from Silurian to Permian, and therefore, it is probably an ophiolite mrlange. The discovery of Late Permian Albaillella sp. cf. A. excelsa provides more reliable evidence supporting the existence of a Permian relic ancient oceanic basin in the western part of Xinjiang South Tianshan.     

Cenomanian florule of Nammoura, Lebanon

The mid-Cenomanian fish beds of Nammoura, Mont-Liban district, Lebanon contain a diverse fauna of aquatic and terrestrial vertebrates, a few crustaceans and moderately well-preserved plant remains of which a single species,Sapindopsis anhouryi , was previously described by Dilcher & Basson (1990). We add 11 species of ferns, gymnosperms and angiosperms of which Nammouria cretacea gen. et sp. nov, Nupharanthus cretacea gen. et sp. nov., Sapindopsis libanensis sp. nov. and Nammourophyllum altingioides gen. et sp. nov. are new taxa. The florule differs markedly from both Early Cretaceous and Turonian plant assemblages of the Middle East, thereby representing a distinct stage of the regional floristic evolution. Its phytogeographic affinities are with contemporaneous floras of North America, Central Europe and the Crimea. A combination of such features as xeromorphism, the prevalence of compound leaves, and the presence of deciduous angiosperm components and gymnosperms may indicate climatic conditions similar to those of the present day Mediterranean.     

The Upper Jurassic–Lower Cretaceous of eastern Heilongjiang, northeast China: stratigraphy and regional basin history

In eastern Heilongjiang, the Upper Jurassic is marine and restricted to the Suibin and Dong’an areas, where it is characterized faunally by Callovian–Volgian (Tithonian) bivalves and florally by dinoflagellates. The Lower Cretaceous is widely distributed in eastern Heilongjiang, and characterized faunally by Berriasian–Valanginian bivalves, Barremian–Albian ammonites and Aucellina, and florally by dinoflagellates. To the west, the marine facies grade into non-marine beds. Thus, in the east, for example in the Dong’an and Dajiashan areas, near the northwestern Palaeo-Pacific, the Lower Cretaceous is marine; westward, in the Yunshan, Longzhaogou, Peide, and Zhushan areas, marine and non-marine deposits alternate, whereas further west still, e.g. in the Jixi Basin, non-marine facies are intercalated with marine beds. This regional distribution is indicative of a large, shallow embayment opening eastwards to the Palaeo-Pacific; during the Early Cretaceous successive transgressive-regressive events influenced the climate and biota of eastern Heilongjiang and northeastern China. Many of the Lower Cretaceous sections contain abundant coals, demonstrating that in this region the Early Cretaceous was an important coal-forming period. Some non-marine bivalve species are common to the Lower Cretaceous Jixi Group of eastern Heilongjiang, the Jehol Group of western Liaoning and the Transbaikalian Group of Siberia, suggesting that these groups are of comparable Early Cretaceous age.     

New ammonite zonation of the lower Callovian in North Siberia

The lower Callovian succession observable in cliffs of Anabar Bay and Bolshoi Begichev Island is described with consideration of zonal subdivisions and beds with ammonites. The unified summary biozonation suggested for North Siberia includes the Cadoceras elatmae Zone with C. frearsi and C. elatmae (instead former C. anabarense) subzones, subsequent C. tschernyschewi and C. tolype zones, and successive C. cf. sublaeve, Rondiceras milaschevici, and Cadoceras ex gr. durum (formerly part of the middle Callovian) beds. As in Siberia and East Europe there are species in common C. elatmae (Nik.), C. frearsi (Orb.), C. tolype Buck., and C. emelianzevi Vor.; certain ammonite zones of Siberian succession are directly correlated with the East European, East Greenland and standard zonations. It is concluded that the lower Callovian is completely represented in Siberia. The lower part of the interval, formerly attributed to the middle Callovian, represents the upper part of the lower Callovian Substage. Zones established in the lower Callovian succession of Siberia are contiguous, whereas equivalents of the Elatmae Subzone and Tschernyschewi Zone have not been distinguished in sections of East Greenland. Evolutionary trends of species in subfamily Cadoceratinae are preliminary discussed.     

Saddle-shaped reticulate <Emphasis Type="Italic">Nummulites</Emphasis> from Early Oligocene rocks of Khari area,SW Kutch,India

Saddle-shaped reticulate Nummulites from the Early Oligocene rocks of Khari area, SW Kutch, India is reported here for the first time. Unusual shape of this Nummulites is due to the curved nature of the coiling plane, indicating space constrained postembryonic test growth. With regular development of chambers, septa and septal filaments, the saddle-shaped Nummulites constitutes the third morphotype of N. cf. fichteli Michelotti form A. Other morphotypes of the species reported earlier include inflated lenticular and conical tests. Multiple morphotypes of N. cf. fichteli form A indicates varied test growth in response to substrate conditions. Morphological variability exhibited by N. cf. fichteli form A from Kutch and some Early Oligocene reticulate Nummulites from the Far East are comparable. This faunal suite is morphologically distinct from the contemporary reticulate Nummulites of the European localities.     

Early Serpukhovian (late Mississippian) microflora from the Guadiato Area (southwestern Spain)

Calcareous microflora occur commonly in the early Serpukhovian (late Mississippian) rocks from the Guadiato Area (southwestern Spain) despite the fact that this area contains mostly siliciclastic sediments. The microflora recorded in the carbonate beds is regarded as representative of both relatively deep‐water and shallow‐water facies and can be compared with the slope and shelf facies environments distinguished in the Guadiato Area. Up to 45 algal taxa have been identified in the carbonate beds, of which 26 taxa occur in the relatively deep‐water assemblages, whereas the shallow‐water assemblages are composed of up to 43 taxa. The entire algal assemblage is dominated by calcifoliids, common cyanobacteria and incertae sedis, but the shallow‐water assemblages contain more commonly dasyclads, red algae and aoujgaliids. Most of these taxa are present, but poorly known, in other Serpukhovian carbonate platforms in the western Palaeotethys. Some algae (Hortonella uttingii, Kamaenella tenuis and Koninckopora inflata), usually regarded as being restricted to the Viséan, have been found in Serpukhovian rocks in the Guadiato Area, and also in Algeria, thus their stratigraphic ranges might be extended up to the Serpukhovian. Other important taxa include: Archaeolithophyllum, Cabrieropora, Calcifolium, Falsocalcifolium, Fourstonella, Frustulata, Kulikia, Neoprincipia and ‘Windsoporella’, which are exceptionally recorded in Serpukhovian rocks, or not recorded at all, because they are typically recorded in the Pennsylvanian (cf. Clavaporella), although some of them show earlier occurrences in Viséan rocks (Claracrusta, Paraepimastopora and Sparaphralysia). Some of the algal taxa can be considered as potential regional markers for the Serpukhovian, such as Archaeolithophyllum, cf. Clavaporella, Frustulata and Girvanella (?) sp. The algal assemblages found in the Guadiato Area show the greatest similarities with those in the Béchar‐Mézarif (Algeria), Pyrenees and Montagne Noire (southern France). Copyright © 2005 John Wiley & Sons, Ltd.     

The first finding of reliable Jurassic radiolarians in the Crimea

Radiolarians of Leugeonidae Yang et Wang, 1990, which represent a morphologically distinctive group of spherical radiolarians of the Spumellaria order, were found for the first time in Crimea and reliably confirm the Jurassic age of the finding. The nodules, which host the Jurassic radiolarians, were collected by A.S. Alekseev in 1983 in the terrigenous sequence of the Lozovskaya tectonic zone. The radiolarian assemblage in the nodules includes Levileugeo ordinarius Yang et Wang, Triactoma jonesi Pessagno, Pseudocrucella aff. prava Blome, Paronella kotura Baumgartner, P. ex gr. mulleri Pessagno, and Praeconocaryomma sp. The Levileugeo genus is easily identified due to its unique hexagonal element, which is typical only of the Jurassic, in particular, Upper Bajocian–Lower Tithonian radiolarians.     

New Bathonian (Middle Jurassic) ammonite assemblages from Kutch, India

The Bathonian ammonite assemblages have been previously poorly recorded in Kutch. The present study has unearthed a rich array of ammonite taxa ranging from the Middle to Upper Bathonian. While Oxycerites Rollier (1909) is a new record from Kutch, the oldest occurrence of Choffatia Siemiradzki (1898) has been found from the Middle Bathonian horizon. Oxycerites cf. orbis (Giebel) is a zonal index of the Late Bathonian in other areas and thus facilitates interprovincial correlation. Besides, palaeobiogeographic and stratigraphic distribution of many species have been modified based on new information. For example, macrocephalitin species, i.e., Kamptokephalites cf. etheridgei Spath (1928), Macrocephalites bifurcatus transient intermedius Spath (1928), M. cf. mantataranus Boehm (1912) were previously known from West Pacific, Indonesia have been now found in Kutch. Gracilisphinctes Buckman (1920) has been previously known to occur during the Middle Bathonian time, the present work extends its stratigraphic distribution up to the definite Upper Bathonian horizon. Procerites hians (Waagen) an endemic species in Kutch previously known from the Upper Bathonian beds, its stratigraphic range has been extended down to the Middle Bathonian.Detail taxonomy of the newly obtained taxa has been done and in many cases sexual dimorphism has been recognized.     

Stratigraphical correlation of the Late Jurassic Lourinhã Formation in the Consolação Sub‐basin (Lusitanian Basin), Portugal

The c. 700 m thick succession of continental–brackish‐marine deposits forming the Lourinhã Formation, cropping out along the coast of western Portugal between Baleal and Santa Cruz, has been correlated using laterally persistent shelly marker beds. Three shelly units record the episodic establishment of relatively short‐lived, brackish‐marine embayments, transgressing from the southwest, onto a low‐lying coastal plain. The succession displays systematic changes in facies types and stacking patterns reflecting differences in fluvial style, bedload character and palaeontological content. Based on these observations, four new members for the Lourinhã Formation are proposed: the Sáo Bernardino, Porto de Barças, Areia Branca and Ferrel members. New biostratigraphical data indicate that the Lourinhã Formation is Late Kimmeridgian to earliest Early Tithonian in age. This age has also been obtained from the underlying mixed carbonate and clastic deposits of the Abadia Formation at Consolação. As a result, these latter sediments are now re‐assigned to the Alcobaça Formation, a lithostratigraphical term currently in use in other areas of the Lusitanian Basin. Improved regional mapping of the Lourinhã Formation has established a new sub‐basin within the western parts of the Lusitanian Basin. This sub‐basin, now named the Consolação Sub‐basin, is bounded to the east by the Lourinhã–Caldas de Rainha (L–C) fault zone and to the west by the Berlengas Horst. Copyright © 2013 John Wiley & Sons, Ltd.     

The Mesozoic ostracod genus Arculicythere Grékoff: further evidence for the southern Gondwana seaway

This paper demonstrates that Arculicythere Grékoff is a widespread taxon in the uppermost Upper Jurassic and Lower Cretaceous of Gondwana. It occurs in Madagascar, India, Israel, South Africa, the Falklands Plateau, Argentina and Australia. The earliest record is from the Upper Tithonian of Madagascar but the most profuse occurrences are in the Albian, when the genus was very widespread around Gondwana. Its distribution seems to be associated with a major southern Gondwana seaway, and the genus provides additional proof of the existence of this corridor. Unlike another endemic gondwanine genus, Majungaella Grékoff, which ranged from earlier in the Jurassic but extended into the Neogene in the Antarctic, or Rostrocytheridea Dingle that survived into the Campanian of the Antarctic, Arculicythere seems to have become extinct in the Albian.