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There are several source rock units in the Gulf of Suez graben, but the Upper Cretaceous–Miocene sequence has probably produced most of the commercial hydrocarbons in this petroleum province. One hundred and nine shale, marl and marly shale samples collected from five wells in the West Esh El Mellaha Concession and surrounding area were studied by petrographic and organic geochemical methods to determine organic facies, depositional paleoenvironment, and thermal maturity. We also investigated the molecular and stable carbon isotopic compositions of nine oil samples to establish genetic relationships with the source rock samples. Pyrolysis data for samples from the Cenomanian–Santonian Matulla, Paleocene Esna, Eocene Thebes, Oligo-Miocene Nukhul and Lower–Middle Miocene Rudeis formations contain hydrogen-poor terrigenous Type-III to II/III kerogen. However, the Campanian–Maastrichtian Brown Limestone samples contain Type-II and Type-II/III kerogens indicating very good to excellent generation potential. The acyclic isoprenoids and normal alkane distributions and biomarkers in the source rock extracts indicate derivation from bacteria and algae, with varying contributions from land plants, deposited under suboxic to anoxic conditions in normal marine to higher salinity waters. The oil samples have high sulfur content and low to moderately high API gravity, typical of mature oils from pre-rift marine carbonate or calcareous shale lithofacies. Hierarchical cluster analysis (HCA) of 18 source-related biomarker ratios revealed four genetic families of oil samples. The two South Malak-1 oils (Family-4) are substantially different from the Rabeh E−8 and Rabeh E−10 (Family-1), Rabeh-1 and Hurghada-1 (Family-2) and Abu Marwa-1 and Wadi El Sahl-1 (Family-3) oil families, which are more closely related. Principal component analysis (PCA) and HCA based on the 18 ratios for the total data from extracts and oils indicate three groups. The South Malak-1 oils seem to be most closely related to the two Brown Limestone extracts. Group-1 oils appear to represent mixtures with one end member consisting of the South Malak-1 oils and the Brown Limestone source rock, but the other end member is not in the dataset.

The collision between India and Eurasia and the subsequent uplift of the Qinghai–Xizang plateau region of the Eurasian continent during the latest Mesozoic and Cenozoic had a significant environmental impact on the region. Understanding the vegetation of both palaeocontinents prior to the collision is crucial for interpreting the evolution of their floras and climatic changes during this period. The composition of the vegetation and climate of the plateau from the Middle Jurassic until the end of the Oligocene are inferred herein from the composition of 14 palynofloras and compared with other regions of China. The palynofloras are similar to those of eastern and northwestern parts of China but bear their own unique features brought about by differing climatic influences. Overall, a warm–hot, arid–semi-arid climate prevailed over the plateau during most of the period from the Middle Jurassic until the end of the Cretaceous. The climate cooled and humidity increased in the Paleogene, and especially during the Oligocene. The long-term climatic change in the Qinghai–Xizang plateau region of the Eurasian continent during the Middle Jurassic–Paleogene that is indicated by the miospore assemblages is broadly comparable to the isotope-based SST (sea-surface temperature) changes that have been identified. It is apparent that climatic changes on a global scale were primarily responsible for controlling the composition and distribution of the vegetation on the plateau; no monsoon features are detectable in the northwestern interior of China. A maximum estimation of 2890 m surface palaeoelevation is inferred for the central and northern plateau during the Oligocene based on vegetation analysis, which is lower than previous estimations based on oxygen isotope and coexistence analyses. The elevation of the southern part of the study area, i.e. the area south of the Gandise Mountains, was low, close to sea-level.

A palynofacies and organic geochemical investigation has been undertaken on 46 core and cuttings samples taken from seven wells drilled in the NC115 Concession, Murzuq Basin, south-west Libya. Most of the samples yielded marine and non-marine palynomorphs in a fair to good state of preservation, which together with palynological data have been used to confirm the age, determine the environment of deposition, and evaluate the petroleum source potential of the Tanezzuft Formation. The palynological assemblage recovered from the basal Hot Shale contains an abundance of acritarchs, chitinozoans and cryptospores, with some taxa, such as Plectochitina sp., Evittia remota, and Tetrahedraletes medinensis, indicating an early–mid Rhuddanian (early Llandovery) age for this unit. The deposits overlying the Hot Shale yielded diverse assemblages of palynomorphs, the occurrence of Angochitina qusaibaensis and Leiofusa banderillae in particular indicating a late Rhuddanian–Telychian (Llandovery) age. Two palynofacies associations have been identified. The Hot Shale palynofacies (PF-A) contains Type-II ≥ I kerogen, which is highly oil-prone and reflects a distal suboxic–anoxic sedimentary environment. The palynofacies of the overlying deposits of the Tanezzuft Formation (PF-B) is dominated by Type-II/III kerogen, which is both oil- and gas-prone, and indicates depositional conditions that range from distal dysoxic–oxic shelf to mud-dominated oxic shelf (distal shelf). Rock-Eval pyrolysis results indicate that the Hot Shale is organically-rich with an average total organic carbon (TOC) content 7.23 wt%, whereas the TOC of the overlying deposits averages 0.62 wt%. The organic matter in the Hot Shale has the capability of generating more liquid hydrocarbons than the rest of the formation, which lies within the early oil-maturity window. A simulated burial history for the NC115 Concession allowed the time and magnitude of hydrocarbon generation from the main Silurian Tanezzuft Formation source rock to be determined. Oil generation from this source rock took place during the Carboniferous/mid-Cretaceous period, whereas the maturation level for gas had not been reached at this stage.

Two palynofacies associations are documented from the Silurian Tanezzuft Formation in the Ghadames Basin. These are characteristic of the basal ‘Hot Shale’ and the overlying deposits, referred to here as the Cold Shale. The former reflects deposition in distal suboxic anoxic conditions and is dominated by highly oil-prone amorphous organic matter (AOM) typical of deposition in generally anoxic, restricted marine basins. Only a few acritarchs, prasinophyte algae and chitinozoans occur in association: virtually no spores or cryptospores were recorded. Thick-walled prasinophytes are most numerous in this part of the Tanezzuft Formation in both the Ghadames and Murzuq basins, suggesting enhanced surface water productivity. Deposition took place after the melting of the Late Ordovician ice sheets, which led to a major marine transgression. The palynofacies recorded from the overlying ‘Cold Shale’ deposits indicate deposition in distal shelf and basin conditions that were also relatively anoxic. They contain more palynomorphs, especially acritarchs, and generally less AOM. The phytoplankton assemblages are dominated by simple and thin-walled prasinophyte algae (leiospheres), suggesting dysoxic–anoxic conditions. Overall the middle and the upper parts of the Tanezzuft Formation are regarded as being deposited in distal dysoxic–anoxic shelf, distal dysoxic–oxic shelf and distal suboxic–anoxic basin respectively. Because chitinozoans are very rare, age determinations of the samples investigated are based mainly on acritarchs. The Hot Shale is dated as early-mid Rhuddanian (early Llandovery) whereas the rest of the formation is considered to late Rhuddanian–Telychian in age. As documented previously from other samples of the Tanezzuft Formation in both the Ghadames and Murzuq basins, the Hot Shale has a very high TOC content and excellent source potential for liquid hydrocarbons, whereas rest of the formation is less rich in organic matter with larger terrestrial and oxidized components and hence reduced potential for sourcing hydrocarbons (both oil and gas).

During the Cretaceous Period, the Indian Plate separated from Gondwana and drifted northwards, eventually colliding with Eurasia at the end of the period or in the early Cenozoic. This led to major changes in the composition of the flora and fauna of the region. Palynomorph assemblages from Cretaceous deposits in Gamba County, southern Xizang (Tibet), China, are analyzed herein in an attempt to determine how the vegetation of the northern margin of the Indian Plate changed. The Gamba assemblages were initially similar in composition to those from Australia but by the Santonian Stage they were more similar to those of North Africa. Differences from the former are increasingly apparent through the Albian–Cenomanian transition. The rate of evolution of the Gamba flora was about the same as that of the Australian flora prior to the Albian, somewhat slower during this stage, but faster from the Cenomanian onwards, implying that this was, to a large extent, a result of the separation of the Indian Plate from Gondwana and its northward drift during the Cretaceous Period. During the Albian, the Australian block drifted eastwards whereas the Indian Plate remained relatively static. This resulted in few changes in the Gamba palynoflora but many in palynofloras from Australia. However, the northward movement of the Indian Plate in the Late Cretaceous led to pronounced changes, with numerous inceptions of genera and species in the Gamba succession. Of these, many have an African or equatorial distribution and none has connections with Australia, indicating that the climate at this time was similar to that of North Africa and that separation from Australia was complete. The arrival of the Indian Plate in equatorial regions allowed floral exchange between its northern part and North Africa during the Santonian.

Palynofloras provide many clues about the composition of past terrestrial vegetation and the conditions in which the plants lived. Here we describe a new Early Cretaceous palynoflora from the western Portuguese Basin in the Estremadura region. A palynomorph assemblage of 34 genera and 55 species was extracted from samples collected from the site of Casal do Borracho in the municipality of Torres Vedras. The rocks concerned belong to the Almargem Formation, which is considered to be of late Barremian to early Aptian age. The beds sampled are dominated by kaolinite, illite or smectite. Of the 22 samples processed for palynological analysis, only five from beds of varying clay mineral composition proved to be productive. The assemblages recovered are dominated by representatives of the fern family Anemiaceae, mainly the spore genera Appendicisporites, Cicatricosisporites, Costatoperforosporites and Klukisporites. Zygospores of Zygnemataceae occur in association. There are also numerous bisaccate and cheirolepidiaceous conifer pollen. Angiosperm pollen grains are scarce and represented by the genera Clavatipollenites, Mayoa and Pennipollis. Overall, the palynoflora of Casal do Borracho suggests a locally wet environment in a tropical/subtropical climate, with much of the gymnospermous component indicating more arid conditions not far away at the time of deposition, an interpretation that is supported by data on the clay mineral assemblages recovered from the succession.

International audience; Further to the work published by Néraudeau et al. six years ago, palynological matter recovered from the lignitic bone bed of Angeac in Charente (south-west France) has been re-examined in order to provide more evidence of its age, the previous Hauterivian–Barremian interpretation being regarded as controversial. The samples come from four sedimentological units, An2–An5, which together yielded an assemblage of 34 species, taxonomically dominated by palaeoecologically significant lygodiaceous verrucate spores, including eight species attributable to the genus Concavissimisporites and three species of Trilobosporites. A few bisaccate pollen grains, including Vitreisporites pallidus, have been recovered, but the gymnospermous pollen spectrum is clearly dominated by the cheirolepidiaceous genus Classopollis, its abundance diminishing progressively upwards from units An4 to An2. The great abundance and diversity of verrucate forms, along with the presence of other spores typical of Lower Cretaceous deposits, such as Aequitriradites verrucosus, and the scarcity of specimens referable to Cicatricosisporites, render this assemblage most similar to those of the Hastings Group of southern England, and the Bückeberg Formation in north-western Germany. The time of deposition is, therefore, more likely to have been Berriasian–Valanginian rather than Hauterivian–Barremian, as previously stated. The associated small assemblage of megaspores is consistent with this determination. Except for Trilobosporites and Concavissimisporites, the use of several other genera commonly applied to Mesozoic verrucate spores, such as Converrucosisporites and Impardecispora, is considered unnecessary. To support this assertion, a Principal Components Analysis has been carried out on 120 verrucate spores from sedimentological units An2–4, taking into account ten morphological variables. The results show that specimens attributable to Trilobosporites are well be separated from the main cluster, which corresponds to Concavissimisporites, underlining the futility of using more than two genera for the species concerned.

Sixteen organic-rich argillaceous limestone and black shale samples from three wells with up to 16 wt% TOC (average 9.32 wt%) from the Middle–Upper Jurassic Naokelekan Formation in the west Zagros Basin of northern Iraq were evaluated as source rocks. Both organic geochemical and molecular data indicate an open marine environment at the time of deposition, leading to accumulation of Type-II and Type-III kerogen with varying oil and gas generation potential. The predominance of short-chain n-alkanes (n-C13–n-C19), and C27 and C29 steranes, and absence of oleanane confirm the dominantly planktonic/bacterial and algal origin of the organic matter. Organic richness, low Pr/Ph, and high C35/C34 homohopane ratios suggest alternating anoxic to suboxic depositional conditions. Biomarker distributions are consistent with sporadic anoxia, with unequivocal evidence for stratification of the water column and hypersalinity. The 22S/(22S + 22R) ratios for C32 homohopanes, moretane/hopane, and C29 sterane 20S/(20S + 20R) and ββ/(ββ+αα) ratios vary irregularly, whereas the C27 diasteranes, Ts/(Tm + Ts), triaromatic cracking and MDR ratios vary substantially and increase with burial depth among different homologues within the same sample set, indicating the threshold to peak of the oil-generation window. Based on hierarchical cluster analysis (HCA) and principal component analysis (PCA) of 13 selected source-related biomarker ratios, the source rock extracts have been divided into three groups: Group-1 from the Ba-1 well, Balad oil field, and Groups-2 and -3 from the Aj-8 and Aj-12 wells, respectively, in the Ajil oil field.

The non-marine Wealden succession of southern England contains a great variety of fossils, new finds of which continue to reveal novel insights into the animals and plants that inhabited this part of the world during much of the Early Cretaceous. Although seldom common, careful searching during the past few years has yielded megafossils that add to previous knowledge of occurrences of taxa and palaeoenvironmental conditions. Particularly significant in this respect has been the recovery of a large number of new insect species, but there have also been numerous finds of vertebrate bones and other body parts, such as teeth, skulls, a claw and a cranial endocast. In addition, the taxonomy of some of these groups and, in the case of dinosaurs, the ichnotaxonomy of their footprints and trackways, has been reviewed and/or reassessed. In this paper, we provide an illustrated account of the research that has been published on Wealden geology and the fossils that have been recovered from the succession since a field guide to English Wealden fossils was issued by the Palaeontological Association in 2011. It is aimed at providing the reader with a document of first resort for fossil identification purposes and a lead into the literature for further information.

The partially reticulate sculpture of Molaspora aspera sp. nov., a marsileaceous megaspore from a Cenomanian deposit in western France, distinguishes it from other species of Molaspora. An acrolamella entirely surrounds and obscures a small tetrad scar, a feature that has been demonstrated hitherto within members of the genus only in M. fibrosa. It was also encountered for the first time in M. lobata, with which the new species is associated in the same French mesofossil assemblage. The ultrastructure of the sporoderm of M. aspera is similar to that of M. lobata, but differs particularly in that the inner epispore is markedly thicker and may also contain numerous large, homogeneous spherules or, alternatively, holes of comparable dimensions and only a few small spherules. It is possible that these are a response to some hostile bacterial or other activity when the developing sporoderm was partially permeable. The cavity replacing part of the epispore in one of the specimens, and in the specimen of...

Thirty-six Silurian core and cuttings samples and 10 crude oil samples from Ordovician reservoirs in the NC115 Concession, Murzuq Basin, southwest Libya were studied by organic geochemical methods to determine source rock organic facies, conditions of deposition, thermal maturity and genetic relationships. The Lower Silurian Hot Shale at the base of the Tanezzuft Formation is a high-quality oil/gas-prone source rock that is currently within the early oil maturity window. The overall average TOC content of the Hot Shale is 7.2 wt% with a maximum recorded value of 20.9 wt%. By contrast, the overlying deposits of the Tanezzuft Formation have an average TOC of 0.6 wt% and a maximum value of 1.1 wt%. The organic matter in the Hot Shale consists predominantly of mixed algal and terrigenous Type-II/III kerogen, whereas the rest of the formation is dominated by terrigenous Type-III organic matter with some Type II/III kerogen. Oils from the A-, B- and H-oil fields in the NC115 Concession were almost certainly derived from marine shale source rocks that contained mixed algal and terrigenous organic input reflecting deposition under suboxic to anoxic conditions. The oils are light and sweet, and despite being similar, were almost certainly derived from different facies and maturation levels within mature source rocks. The B-oils were generated from slightly less mature source rocks than the others. Based on hierarchical cluster analysis (HCA), principal component analysis (PCA), selected source-related biomarkers and stable carbon isotope ratios, the NC115 oils can be divided into two genetic families: Family-I oils from Ordovician Mamuniyat reservoirs were probably derived from older Palaeozoic source rocks, whereas Family-II oils from Ordovician Mamuniyat–Hawaz reservoirs were probably charged from a younger Palaeozoic source of relatively high maturity. A third family appears to be a mixture of the two, but is most similar to Family-II oils. These oil families were derived from one proven mature source rock, the Early Silurian, Rhuddanian Hot Shale. There is a good correlation between the Family-II and -III oils and the Hot Shale based on carbon isotope compositions. Saturated and aromatic maturity parameters indicate that these oils were generated from a source rock of considerably higher maturity than the examined rock samples. The results imply that the oils originated from more mature source rocks outside the NC115 Concession and migrated to their current positions after generation.

One hundred and thirty-six core and cuttings samples from Upper Cretaceous–Eocene deposits that are believed to include the most important source rocks in the Sirte Basin have been subjected to Rock-Eval pyrolysis, total organic carbon measurements, and palynofacies and microfacies analyses to determine palaeoenvironments and the thermal maturation history of the succession. It is apparent that the lower part of the Bahi Formation, the oldest rock unit examined, reflects a basin margin environment under the influence of freshwater input. Shallow marine, near-shore, inner shelf, suboxic–anoxic conditions, which are first suggested by the uppermost deposits of the Bahi Formation, prevailed for much of the time during deposition of the younger Cretaceous Etel, Rachmat, Sirte and Kalash formations. Shallow supratidal and intertidal sub-environments alternating with deeper environments of shelf embayments associated with a maximum rise in sea level are indicated by the Paleocene Farrud Member of the Beda Formation. The Zelten Formation consists of shallow intertidal and lagoonal facies, and the overlying Paleocene–Eocene Kheir Formation reflects relatively shallow marine sedimentation in mid to outer shelf environments alternating with short-lived, shallow, intertidal-lagoonal to supratidal conditions. The TOC content of the Upper Cretaceous samples examined is mostly moderate (up to 2.04%), the organic matter consisting of Types II and II/III kerogen. Differences in hydrocarbon generation potential are linked to varying proportions of aquatic versus terrigenous organic matter in the samples examined and hence to depositional conditions. Combined geochemical and palynofacies data reflect deposition mainly in weakly reducing to suboxic settings and suggest that immature to early mature gas-prone source rocks are within the Etel, Rachmat and some of the Sirte Formation, and mature oil/gas-prone source rocks are within the Sirte and Kalash formations.

The Ghadames Basin of NW Libya contains more than 10 B brls oil-equivalent in Palaeozoic siliciclastic reservoirs which are charged by organic-rich “hot shales” in the Lower Silurian (Rhuddanian) Tanezzuft Formation. Geochemical analysis of 85 shale samples and ten oils from three fields (NC2, NC4 and NC7) in the central and northern part of the basin provides a robust description of the Tanezzuft – Mamuniyat/Acacus petroleum system in this region, and of the associated source facies and oil families. The shale samples underwent total organic carbon (TOC) analysis and Rock-Eval pyrolysis, and the ten crude oil samples were analysed by gas chromatography – flame ionization detection (GC-FID) and GC-mass spectrometry (GC-MS) of the saturated and aromatic hydrocarbon fractions, accompanied by stable carbon isotopic analysis. Organic matter ranges from Type II to mixed Type II/III kerogen with varying oil and gas generation potential in the early to main stages of the oil generation window. The analysed oils are characterised by low sulphur, nickel and vanadium contents, and relatively high API gravity (34.9–46.8oAPI). Biomarkers suggest that they were generated from marine shales containing abundant Type II to mixed Type II/III kerogen deposited in mildly anoxic – suboxic conditions with a dominance of C29 over C27 or C28 steranes, indicative of a source rich in brown algae and cyanobacteria. Their close stratigraphic association and biomarker characteristics support a Tanezzuft “hot shales” source for the Mamuniyat and Acacus oils in the three fields. Maturity-related parameters based on terpanes, steranes, aromatic hydrocarbons and low molecular-weight hydrocarbons, suggest generation from marine shales in the early to peak oil-generation window. The ZE3-NC7, A19-NC7 and A20 NC7 oils from the NC7 oil field are significantly more mature than those from the NC2 and NC4 fields. This indicates a difference in expulsion timing and may be related to the presence of two “hot shales” or to fault-triggered vertical migration preceding and during the Neogene.

A detailed organic geochemical study of 20 core and cuttings samples collected from the Silurian Tanezzuft Formation, Murzuq Basin, in the south-western part of Libya has demonstrated the advantages of pyrolysis geochemical methods for evaluating the source-rock potential of this geological unit. Rock-Eval pyrolysis results indicate a wide variation in source richness and quality. The basal Hot Shale samples proved to contain abundant immature to early mature kerogen type II/III (oil–gas prone) that had been deposited in a marine environment under terrigenous influence, implying good to excellent source rocks. Strata above the Hot Shale yielded a mixture of terrigenous and marine type III/II kerogen (gas–oil prone) at the same maturity level as the Hot Shale, indicating the presence of only poor to fair source rocks.

Palynological and biomarker characteristics of organic facies recovered from Cretaceous–Miocene well samples in the Ras El Bahar Oilfield, southwest Gulf of Suez, and their correlation with lithologies, environments of deposition and thermal maturity have provided a sound basis for determining their source potential for hydrocarbons. In addition to palynofacies analysis, TOC/Rock-Eval pyrolysis, kerogen concentrates, bitumen extraction, carbon isotopes and saturated and aromatic biomarkers enable qualitative and quantitative assessments of sedimentary organic matter to be made. The results obtained from Rock-Eval pyrolysis and molecular biomarker data indicate that most of the samples come from horizons that have fair to good hydrocarbon generation potential in the study area. The Upper Cretaceous–Paleocene-Lower Eocene samples contain mostly Type-II to Type-III organic matter with the capability of generating oil and gas. The sediments concerned accumulated in dysoxic–anoxic marine environments. By contrast, the Miocene rocks yielded mainly Type-III and Type-II/III organic matter with mainly gas-generating potential. These rocks reflect deposition in a marine environment into which there was significant terrigenous input. Three palynofacies types have been recognized. The first (A) consists of Type-III gas-prone kerogen and is typical of the Early–Middle Miocene Belayim, Kareem and upper Rudeis formations. The second (B) has mixed oil and gas features and characterizes the remainder of the Rudeis Formation. The third association (C) is dominated by amorphous organic matter, classified as borderline Type-II oil-prone kerogen, and is typical of the Matulla (Turonian–Santonian) and Wata (Turonian) formations. Rock-Eval T max , PI, hopane and sterane biomarkers consistently indicate an immature to early mature stage of thermal maturity for the whole of the studied succession.

The composite SK-1 borehole drilled in the Songliao Basin, north-east China penetrated non-marine rocks of Late Cretaceous age, some of which yielded assemblages of Ghoshispora . Species of this megaspore genus have palaeoenvironmental and potentially also biostratigraphic significance. Their value as determinants of age is, however, currently limited because many are difficult if not impossible to differentiate as our appraisal of their morphological characters reveals. This review helped to put the specimens recovered from the SK-1 borehole into context and led to the identification of a few of the specimens as Ghoshispora kondinskayae (Srivastava et Binda) Srivastava, G. sp. cf. G. bella (Kondinskaya) subsp. deltoidea Kutluk et al., and G. sp. cf. G. rara (Kondinskaya) Srivastava. Several revealed characters under the scanning electron microscope that differ from those of previously published species: two of these are described as new, namely Ghoshispora zhaoi sp. nov. and G. bulbosa sp. nov. Owing to a lack of sufficient specimens six other morphotypes have had to be identified in open nomenclature as G. sp. A–F. It is likely that the parent plants of all of the species grew in and/or close to standing water. The comparatively large number of very small specimens in association with, and having some of the characters of, the larger representatives of G. zhaoi suggests that a few might be the microspores of this species rather than incompletely developed megaspores.

The spinicaudatan Neodiestheria Chen is an important component of the diverse Early Cretaceous Yanjiestheria fauna in eastern Asia. Examination under a scanning electron microscope of newly collected and well-preserved specimens of Neodiestheria dalaziensis Chen from the Albian Dalazi Formation of Zhixin, Jilin Province, north-eastern China, has revealed morphological features of the carapace not recognized previously, namely that puncta are not only evenly distributed on growth bands near the umbo and gradually merge into a punctate fine reticulation and dense radial lirae on each growth band in the upper-middle part of the carapace, but also occur on growth lines and within the lumina of a fine reticulum, and between radial lirae on growth bands in the middle and lower parts of the carapace. Growth bands in anteroventral, ventral and posteroventral parts of the carapace are also ornamented with transversely elongate large pits (depressions) surrounded by swellings, appearing as a large reticulum superimposed over fine reticulation and radial lirae. These ontogenetically developing morphological patterns on the growth bands of the juvenile stage of the carapace indicate that Neodiestheria is closely related phylogenetically to Triglypta Wang.

Outcrops of the Early Bajocian, Gristhorpe Member (Ravenscar Group) in North Yorkshire have been subjected to a multi-disciplinary analysis which establishes a key reference section at Yons Nab. Eight micro-biofaces types (MBs) are defined based on counts of transitional marine microfaunas, megaspores and plant-derived debris. Associated palynofloral associations (PAs) are used to qualify the micro-biofacies defined to provide an integrated model for interpreting salinity–freshwater trends associated with deltaic progradation and retreat. Megaspore and small-spore trends within the delta-plain are shown to have been closely linked to peat-mires forming in topographic lows, with variations across the delta-plain attributable to the presence of the semi-permanent and seasonal water tables. A reconstruction of the floodplain–peat-mire depositional setting is proposed where the composition of host vegetation (e.g. ferns, lycopsids) varied in relation to groundwater levels. Biostratigraphic correlation within the Gristhorpe Member is attempted using the base of ‘established’ delta-plain deposition (megaspore dominant MBs/spore-dominant PAs) and the top and base agglutinated foraminifera-dominant MBs (brackish). Using these criteria the Gristhorpe Member is modelled in terms of a southward progradation of delta-plain facies into a bay-fill sequence, which persisted at Yons Nab. With the delta-plain established, the MB/PA trends and sedimentology suggest a northward shift towards the higher delta-plain, with seasonal standing water only. The MB/PA model was tested on core samples from the coeval lower Brent Group from northern North Sea well 34/10-B-12 (Gullfaks Field); MB/PA trends are shown to compare closely with those of the Gristhorpe Member at Yons Nab, with the same megaspore/small-spore associations developed within similar lithofacies. On this basis transitional marine, bay-fill and delta-plain deposition are defined in the cored section. These comparative data suggest that the dispersal of megaspore and miospore host floras occurred effectively across the Mid North Sea High, and that they colonized the same niche habitats associated with bay-fill and delta-plain development.

A palynological analysis of 45 samples from six mid-Cretaceous amber-bearing outcrops from Charentes has been carried out. A total of 227 taxa have been recorded in the studied palynofloras. Palynological data support earlier evidence and indicate an early Cenomanian age for the assemblages. The heterogeneous compositions of the palynofloral assemblages indicate the existence of different coastal depositional settings with a variable but usually weak marine influence. The local vegetation was subdivided in various types including herbaceous formations integrating ferns and eudicots which may have colonised frequently-disturbed, fluvial, open environments and xeric arboreal communities dominated by Cheirolepidiaceae and probably integrating drought- and/or salt-tolerant angiosperms and ferns (Anemiaceae and Gleicheniaceae) and other gymnosperms (Araucariaceae, Ginkgoales and scarce Cycadales and Gnetales). The existence of riparian and freshwater wetland communities integrating taxodioids, aquatic and/or hygrophilous angiosperms, ferns, lycopods, mosses and clubmosses is proposed. Coastal/?lagoonal counterparts including plants tolerant to periodical floods by saline or brackish waters is suggested by palynological evidence. Conifer forests mainly integrating Pinaceae and Podocarpaceae in raised hinterlands may also be interpreted on the basis of taphonomical considerations. The wide variety of depositional settings inferred by the palynological data support enhanced transport capabilities for amber and/or a widespread occurrence of producers in local vegetation during the early Cenomanian.

International audience; We describe here the palynological content from the lower Cenomanian plant-rich site of Jaunay-Clan (Vienne, western France), a site that previously yielded exceptional leaf impressions. Altogether, 184 species of palynomorphs have been identified, and two palynological intervals were recognized in the sedimentary sequence. The lower interval is characterized by the taxonomical and numerical dominance of spores of Gleicheniaceae, Cyatheales, and Anemiaceae, while the upper interval is characterized by an abrupt increase in the abundance of Classopollis and the appearance of dinocysts. This shift in the palynological composition, coupled with paleobotanical observations, is interpreted as reflecting a transition from a calm freshwater environment, with occasional droughts to an environment more open to very occasional marine inputs, such as an inner lagoon.The association of Tehamadinium coummia, Trichodinium spinosum, Tricolpites nemejcii, Retitricolporites decorosus, and Microreticulatiporites sacalii, coupled with the absence of Normapolles pollen grains, suggests that the Jaunay-Clan assemblage is early Cenomanian in age, corroborating the previous determination based on lithological and paleontological proxies. However, the Jaunay-Clan palynoflora is considered to be slightly younger than the numerous earliest Cenomanian assemblages described from Charente-Maritime, owing to its resemblance with mid-lower Cenomanian palynofloras from western France. The paleoflora and palynoflora from Jaunay-Clan are similar to other assemblages found in the upper Albian of Spain (Teruel Province), and in the Cenomanian of France and Czech Republic (Peruc-Korycany Formation, La Buzinie, Archingeay). The combined Jaunay-Clan palynoflora and paleoflora is considered to be the most diversified Cenomanian paleobotanical-palynological assemblage described so far in Western Europe.

We describe a new and rather unusual megaspore recovered from Middle Jurassic terrestrial deposits of Yorkshire, England that we name Reticuspinosporites whytei gen. et sp. nov. The contact area is non-trilete and is formed where an outer sculptured layer has not developed. This outer layer covers the remainder of the megaspore and bears novel sculpture consisting of a highly irregular reticulum with areas ‘infilled’ to form plateaus that bear long spines. Analysis of wall ultrastructure reveals a four-layered wall comprising from inside to outside: (i) innermost, separated lamina; (ii) inner homogeneous layer; (iii) central spongy layer; and (iv) outermost homogeneous layer that forms the sculpture. Wall ultrastructure is not entirely diagnostic but is most suggestive of lycopsid affinities. Unusually the megaspores commonly occur in pairs. They are not attached at their contact faces but by their equatorial or distal surfaces through entanglement of their spines. We interpret this feature as possibly an adaptation for floating and transport by water.

The varicoloured Fenghuoshan Group occurs widely in the Qiangtang-Hoh Xil region of the northern Qinghai-Xizang Plateau. Few fossils have been found to date in this sedimentary succession because lithological conditions are not conducive to their preservation. As a result, there has been a long-term disagreement among geologists about its age. Despite a few lists of fossil names in individual publications, no detailed research on the palaeontology, including palynology, has been reported previously. In this study, we recovered many pollen grains and spores from two samples that were collected on the northern slope of Fenghuo Mountain. They indicate an age no younger than Maastrichtian for the upper part of the Fenghuoshan Group. It is considered likely that the entire Fenghuoshan Group represents deposition between the late Early Cretaceous (possibly Albian) and the Maastrichtian. The palynoflora consists mainly of angiosperm pollen, gymnosperm pollen and fern and bryophyte spores being subordinate. Pollen grains referable to the Ephedrales and the Taxaceae–Cupressaceae groups dominate the assemblage, implying a warm, arid climate and subtropical forest–shrub vegetation at the time of deposition.

International audience; A Cenomanian clay lens in Hucheloup Quarry (Maine-et-Loire, north-western France) has yielded 82 foliar compressions and impressions, of which 62 were identified at several taxonomic levels. The plants are ascribed to diverse Pinales (27%), ferns (27%), Ginkgoales (26%), angiosperms (19%) and Cycadales (1%). The most abundant species in the assemblage are Frenelopsis alata (K. Feistmantel) E. Knobloch emend. J. Kvaček (Pinales) and Eretmophyllum obtusum (Velenovský) J. Kvaček (syn. E. andegavense Pons, Bourreau et Broutin) (Ginkgoales). Wood fragments, along with very well-preserved cuticles, have also been recovered and identified. The specimens are usually very fragmentary, indicating that they had been transported over a significant distance before deposition. The Hucheloup clay was probably deposited in a brackish lagoon or in the lower part of an estuary, possibly in an abandoned channel or on a sandbar. The allochthonous flora represents at least two plant communities that developed in a subtropical–tropical climate, and along a salinity gradient in the vicinity of a fluvial network. Use of the fossil-genus Eretmophyllum Thomas emend. Harris in Harris et al. is considered to be the correct choice for ginkgoalean leaves within European Cenomanian deposits; the genus Nehvizdya Hluštík is regarded as a junior synonym. The clay lens has also yielded a palynological assemblage. Although lacking unequivocal indicators of this age and including some taxa that are more typical of older rocks, the composition of the associated, very small megaspore assemblage recovered is consistent with a Cenomanian determination.; Quatre-vingt-deux compressions et impressions foliaires ont été collectées au sein d’une lentille argileuse cénomanienne située dans la carrière de Hucheloup (Maine-et-Loire, France), 62 d’entre elles ayant pu être identifiées. Les macro-restes observés correspondent à des Pinales (27%), des fougères (27%), des Ginkgoales (26%), des angiospermes (19%) et des Cycadales (1%). Frenelopsis alata (K. Feistmantel) E. Knobloch emend. J. Kvaček (Pinales) et Eretmophyllum obtusum (Velenovský) J. Kvaček (syn. E. andegavense Pons, Bourreau et Broutin) (Ginkgoales) sont les deux espèces les plus abondantes de l’assemblage. Des fragments de bois et des cuticules ont également été récoltés et identifiés. Les macro-restes végétaux sont souvent très fragmentés, conséquence d’un transport sur une distance considérable avant dépôt. La lentille argileuse de Hucheloup s’est vraisemblablement déposée au sein d’une lagune saumâtre ou de la partie inférieure d’un estuaire, possiblement au niveau d’un bras-mort ou d’une barre sableuse. La flore, allochtone, comporte des éléments issus de deux communautés végétales distinctes qui se sont développées sous l’influence d’un gradient de salinité aux alentours d’un réseau fluviatile, sous un climat subtropical à tropical. L’attribution des feuilles de Ginkgoales au morpho-genre Eretmophyllum Thomas emend. Harris in Harris et al. au sein des dépôts cénomaniens européens est ici discutée et défendue ; le genre Nehvizdya Hluštík est considéré comme synonyme junior. La lentille argileuse présente également un assemblage palynologique, dont 22 taxons ont été identifiés. Ce dernier est dépourvu d’indicateurs temporels indiscutables et présente des formes typiques de sédiments plus anciens, mais la composition du modeste assemblage associé de mégaspores est cohérent avec un âge cénomanien.

Site 549 of the Deep Sea Drilling Project was drilled on the Goban Spur in the Bay of Biscay in 1981. The core recovered from this North Atlantic location included 290 m of Barremian and possibly partly Hauterivian “syn-rift” deposits overlain unconformably by rocks of early Albian age. The number and variety of spores and pollen grains in the palynomorph assemblages and associated palynofacies through these units together with the presence of some pieces of wood, fragments of foliage, and a few megaspores in the lowest part of the Cretaceous succession suggest that the source area vegetation was, at least initially, relatively close to the site of deposition. Ginkgoalean, bennettitalean, and other gymnosperm groups are represented in the plant mesofossil assemblage but most of the fragments of foliage show cheirolepidiaceous characteristics. Five species belonging to this family have been identified and described. Two of these, Frenelopsis atlantica Zhou and Batten and Frenelopsis ? alvinii Zhou and Batten, are new and one is unnamed. The composition of the three informally identified suites of spore and pollen assemblages recovered from 49 samples through the Early Cretaceous succession is consistent with age determinations of parts of it determined previously on the basis of dinoflagellate cysts, foraminifera, nannoplankton, and other fossils.

A palynological analysis of a Late Jurassic–Early Cretaceous succession in the Himalayan Tethys, Gyangze County, southern Xizang (Tibet) provides, for the first time, evidence of changing palynofloras through the Jurassic/Cretaceous (J/K) boundary. Species that are stratigraphically important and potential markers for delineating the boundary include both miospores and dinoflagellate cysts. The presence of the spores Crybelosporites sp. cf. stylosus, Foraminisporis wonthaggiensis, Jiaohepollis verus and Toroisporis welzowense and the cysts Cassiculosphaeridia delicata and Rhynchodiniopsis serrata imply that the J/K boundary is between samples 06-21-1 and 06-21-3. The occurrence of Aequitriradites spinulosus and Cicatricosisporites spp. a little below this level and of ?Dictyotosporites sp. cf. speciosus slightly above it is also significant. These results show that it is possible to locate the J/K boundary in the Himalayan Tethys near top of the Weimei Formation and the lower part of the Gyabula Formation in southern Xizang. This succession also contains various marine invertebrate fossils, including ammonites, bivalves and belemnites, and thus has considerable potential for erecting an integrated biostratigraphy around the J/K boundary in the eastern Tethyan realm. Palynofloristic correlation implies a more northerly location for the fossil locality at Gyangze than that of northwest Australia during the latest Jurassic and earliest Cretaceous, which can be further constrained to around 43°S.

The late Cretaceous Mukalla Formation of the Mahra Group is present in the subsurface of eastern Yemen. The palynofacies, thermal maturation and hydrocarbon potential of this formation recorded from three exploratory wells in the Qamar Basin are discussed. Two of the wells are in the offshore part of Block 16 and one is in the onshore part. Both organic geochemical and palynofacies analyses indicate that the formation contains oil- and gas-prone kerogen. Rock-Eval pyrolysis and gas chromatography data show a peak thermal maturation stage for organic matter types II/III and III and good conditions for hydrocarbon generation and expulsion. Three major palynofacies types are identified through the succession. These indicate open marine, marginal- to shallow-marine and fluvio-deltaic environments, reflecting multiple marine transgressive and regressive phases during the period of deposition of the formation, which took place in a humid, subtropical to tropical climate.

A new species of spore, Costatoperforosporites friisiae sp. nov., is described from the Early Cretaceous (late Aptian–early Albian) deposits of Catefica in the Lusitanian Basin, western Portugal. Although the morphology of the muri is clearly of the Cicatricosisporites type, the presence of micropores on these sculptural elements and within the intervening grooves is a particularly distinctive feature and more typical of spores that have been attributed previously to Costatoperforosporites. As a result, this genus is emended not only to accommodate Costatoperforosporites friisiae but also to differentiate it more clearly from other, similar, murornate genera. It is considered to represent the family Anemiaceae. So far, Costatoperforosporites friisiae has only been encountered in the Catefica palynoflora. The presence of many other pteridophyte spores, especially of schizaealean derivation, together with abundant cheirolepidiacean remains at this locality, strongly suggests a warm, moist climate and diverse source vegetation., Centre for Marine and Environmental Research, University of Algarve, Portugal, Centre for Interdisciplinary Development and Research on Environment, Applied Management and Space, Lusofona University of Humanities and Technologies, Portugal, Instituto Geológico y Minero de España, España, School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Reino Unido, Institute of Geography and Earth Sciences, Aberystwyth University, Reino Unido, GeoBioTec, New University of Lisbon, Portugal

International audience; The Upper Cretaceous lignite deposits of La Garnache, Vendée (western France), consist of two lignitic clay series, Garnache 1 and Garnache 2, separated by a fault. The first series cropped out to the south of the fault during road works until 2002 but is now covered by an embankment. It has provided numerous pieces of amber containing arthropod and microorganism inclusions. The second lignitic series, exposed to the north of the fault, is rich in fossil wood but devoid of amber. Palynological analysis of Garnache 1 revealed several Normapolles species belonging to the genera Atlantopollis, Complexiopollis, Osculapollis, Plicapollis and Trudopollis, but larger forms typical of Senonian deposits are absent. By contrast, Garnache 2 proved to be dominated taxonomically and numerically by spores (Appendicisporites, Camarozonosporites, Gleicheniidites, Patellasporites, Stereisporites), associated with a few gymnosperm (Cerebropollenites, Phyllocladidites, Classopollis) and angiosperm (Liliacidites, Retitricolpites and a single specimen of the Normapolles Complexiopollis) taxa. Garnache 1 is, therefore, younger than Garnache 2, the latter being clearly Cenomanian in age whereas Garnache 1 is more likely to be Turonian. Lignitic clay of Garnache 1 contains numerous translucent, orange to red, pieces of amber. Vendean amber is rich in aquatic arthropods, such as tanaids and epicarideans (Crustacea), as well as marine or brackish siliceous microorganisms such as diatoms and sponge spicules. These aquatic inclusions indicate that resin-producing trees grew along and close to the seashore. The amber-bearing clay was deposited in a calm, estuarine or lagoonal, muddy environment.

International audience; Diagnoses of the Normapolles pollen genera Hungaropollis, Krutzschipollis, Longanulipollis, Oculopollis and Trudopollis and 55 of their species are emended and many specimens illustrated in order to provide a basis for more successful and consistent identification than has been possible hitherto. These taxa were recovered from palynological preparations of selected samples from Upper Cretaceous deposits in Europe and the eastern USA. As indicated on an accompanying range chart the majority are encountered in Santonian and/or Campanian deposits. Eleven of the species described have been transferred from other genera and are therefore in new combinations, namely: Hungaropollis granulatus (Kedves et Herngreen), Longanulipollis coronatiformis (Góczán et Siegl-Farkas), L. orbicularis (Góczán), L. ornatus (Kedves et Diniz), L. parvoculus (Góczán), L. skarbyae (Kedves et Diniz), Oculopollis artifex (Weyland et Krieger), O. rector (Pflug), O. triceps (Skarby), Trudopollis cuneolis (Góczán et Siegl-Farkas), and T. spinulosus (Skarby). Six are new: Hungaropollis pinguis, Krutzschipollis cucullus, K. immanis, Longanulipollis amabilis, L. lobus and Oculopollis viriosus. Thirteen genera are regarded as synonyms of Hungaropollis (Aveiropollenites and Romeinipollenites), Longanulipollis (Coronatipollis, Intercalaripollis, Portaepollenites and Verruoculopollis), Oculopollis (Druggipollenites, Pseudoculopollis and Semioculopollis) and Trudopollis (Cuneipollis, Felderipollenites, Hofkeripollenites and Kriegeripollenites) respectively. As a result of some of these nomenclatural changes 14 other species are in new generic combinations but are not otherwise considered. Seven morphotypes are identified in open nomenclature and two placed in comparison. This taxonomic synthesis, which updates work published since the 1950s, is aimed primarily at rendering biostratigraphic analyses easier, but it is also a necessary first step towards the resolution of Normapolles taxonomy and the relationships between these pollen grains and biological species.

International audience; This paper provides the sedimentological, palaeontological and biostratigraphical characteristics of a newly discovered lignite-bearing sedimentary succession in western France. The lignitic bed, which is reminiscent of some Wealden facies in southern England, is located in Angeac in the Charentes region. The plant remains occur as three-dimensionally preserved mesofossils (cuticles, charred ferns and seeds, cones and twigs) and larger pieces of wood. The deposits contain variable amounts of such material and at one horizon in particular, an outstanding accumulation of dinosaur teeth and bones. Among the vertebrate remains are the longest sauropod femur (ca. 220 cm) yet found and bones representing an ornithomimosaur herd of at least eight individuals. The palynomorph content of the clay associated with the bones and lignitic material indicates a Hauterivian Barremian age. The abundance in the fossil assemblage of freshwater unionoid bivalves, some preserved in life position, the presence of freshwater algae, and the scarcity of brackish or marine species indicate that the depositional environment was a swamp only very occasionally connected to the sea. The forest bordering the swamp was dominated by cheirolepidiaceous trees co-occurring with a diverse assemblage of ferns

The structure of the sporopollenin wall of fossil megaspores can be usefully applied to the determination of morphological similarities and differences between species and genera, which in turn can aid determinations of botanical relationships. Nine species belonging to seven genera of lycopsid megaspores from European Mesozoic successions that have been examined in thin section under a transmission electron microscope are discussed in this paper. Of these, seven are considered to be referable to the Selaginellales, namely Bacutriletes pragensis, Echitriletes zemechensis, Erlansonisporites sp. ‘pseudomoravica’ type, Horstisporites cenomanicensis, Kerhartisporites kleinii, K. srebrecensis, Ricinospora sp. and Verrutriletes maloninensis. The structure of the exospore of Aneuletes patera, an alete species of hitherto uncertain affinity, also suggests that this has selaginellalean origins. The construction of the wall of Echitriletes lanatus, however, resembles that of representatives of the Isoetales and imp...

Illustrations of, and keys to, mangrove pollen and spores from extant taxa are essential to studies of tropical Quaternary palynology and palaeoecology of estuarine and marine deposits. In this paper we present a pollen morphological “atlas” and identification keys for most of the mangrove flora of the coastal areas of south China, including an interspecific key to the major mangrove elements Rhizophora and Sonneratia. The morphology of the pollen and spores of 38 species of living mangrove and associated plants is described and illustrated by transmitted light photographs and scanning electron micrographs. These descriptions and illustrations, and the identification keys are presented at an achievable taxonomic level. The keys are open for future development so that pollen of other mangrove and associated plants can be accommodated when available. In their present state they should, nevertheless, aid palynological analyses of Quaternary mangrove and associated estuarine and marine deposits, particularly in the South China Sea and surrounding regions, but also elsewhere in tropical and subtropical regions.

In common with the single extant species of the water fern Regnellidium, Regnellidium diphyllum, megaspores of Eocene and Oligocene representatives of this genus are characterized by having twisted, leaflike folds forming an acrolamella around the triradiate suture. The fossil and modern megaspores also have very similar wall ultrastructure and sculpture, and the morphology of the attached microspores of both is indistinguishable. Specimens of one of the species of the Cretaceous megaspore genus Molaspora—namely, Molaspora lobata, with attached microspores from Spain—and spores in the sporocarp Regnellidium upatoiensis from Georgia, United States, share some characters with those of extant Regnellidium, but the surface ornament of the microspores and the ultrastructure of the megaspore and microspore walls are different. The inner layer of the inner perine of M. lobata megaspores is thinner than the outer layer and of more compact, spongiose construction than that of Eocene and Oligocene Regnellidium spor...

Maastrichtian sediments from the eastern Spanish Pyrenees have yielded a variety of mesofossils. The megaspores and megaspore apparatuses are referred to Minerisporites succrassulus Tschudy, Ghoshispora epispinosa sp. nov., Ghoshispora sp., Molaspora lobata (Dijkstra) Hall and Parazolla vallcebrensis sp. nov. Also recovered were specimens of uncertain affinity, some of which are possibly immature P. vallcebrensis, and massulae clusters that might be attributable to either this species or Azolla Lam. Minerisporites succrassulus and megaspores referable to Parazolla have not been recorded previously from beyond North America, and hitherto only one European occurrence of Ghoshispora has been noted. Hence, these new records indicate that the parent-plant groups concerned were more widespread during the Late Cretaceous than previously recognised. It is likely that all of them lived in or close to bodies of fresh water, reflecting a wetland habitat at the time of deposition.

Li, J., Batten, D. J. (2011). Early Cretaceous palynofloral provinces in China: western additions. Island Arc, 20 (1), 35-42.

Two boreholes drilled approximately 75 km apart in the Songliao Basin, Northeast China, have together provided a composite core that represents an almost continuous section through Late Cretaceous–early Paleocene deposits. Eight biozones have been established for this succession of seven formations based on occurrences and associations of biostratigraphically significant palynomorph genera. Seven of these suggest that there was more or less continuous deposition from the late Turonian to the early Paleocene, with the eighth encompassing a Miocene formation that overlies the succession unconformably. This zonation provides a new chronostratigraphic framework for the Late Cretaceous deposits of the Songliao Basin. The ages of most of the formations involved differ from those determined previously. One of the sedimentary units, the Mingshui Formation, includes the Cretaceous/Paleogene boundary, which seems to be indicated by an apparent “mass extinction” of palynomorph taxa, a comparatively rare occurrence outside North America. The upper Quantou Formation, the lowest unit in the succession, is dated as late Turonian–Coniacian, which is much younger than previously thought. The same applies to the overlying Qingshankou and Yaojia formations, and also to the other three (Nenjiang, Sifangtai and Mingshui) but to a lesser extent, in the conformable succession. The Early/Late Cretaceous boundary must now be located probably below the Quantou Formation, either between it and the underlying Denglouku Formation or within the latter.

Li, G., Hirano, H., Batten, D. J., Wan, X., Willems, H., Zhang, X. (2010). Biostratigraphic significance of spinicaudatans from the Upper Cretaceous Nanxiong Group in Guangdong, South China. Cretaceous Research, 31(4), 387-395. Sponsorship: Major Basic Research Projects of the Ministry of Science and Technology, China (National 973 Project 2006CB701403), a Japan Society for the Promotion of Science Fellowship (ID No. L09522), the National Natural Science Foundation of China (40572005), a German Research Foundation (Deutsche Forschungsgemeinschaft) grant (446 CHV 113/259/0-3), and the State Key Laboratory of Palaeobiology and Stratigraphy (SKLPS), Nanjing (20082103).

International audience; Six localities in western France contain deposits of mid Cretaceous age that have yielded small assemblages of megaspores. These are Archingeay-Les Nouillers, Puy-Puy, Les Renardières, La Buzinie and Le Brouillard quarries, and Fouras tidal flat. With one exception, all are within the Charente and Charente-Maritime regions; Le Brouillard is further north in Anjou Province. The productive horizons are in sub-units of previously defined stratigraphic units A, B and C, and range in age from latest Albian or earliest Cenomanian to earliest mid Cenomanian. Owing to a scarcity of records of mid Cretaceous megaspores that can be relied upon for comparison with those recovered in this study, a cautious approach to identification has been adopted. Most forms are only compared to previously described species or referred to in open nomenclature. The most productive sample was from the lower part of sub-unit A1 at Puy-Puy. The assemblage recovered is dominated by spores referable to isoetalean Minerisporites and Paxillitriletes, with a few baculate, rugulate and other lycopsid spores and marsilealean Molaspora rugosa in association. The occurrence of the last of these in particular might indicate that this lowermost unit of the mid Cretaceous succession is earliest Cenomanian rather than latest Albian in age, but the evidence is equivocal. The composition of the assemblages from sub-unit B2 (Fouras tidal flat) and higher levels (La Buzinie, Le Brouillard) is consistent with a Cenomanian age determination and, in common with those from Puy-Puy, Archingeay-Les Nouillers and Les Renardières, indicates a bias towards parent plants that lived in and adjacent to water bodies. Among the forms recorded are species of Ariadnaesporites, Dijkstraisporites and Tenellisporites. The mixed character of the assemblages and the presence of damaged specimens and fragments in all of them lend support to previous interpretations of lacustrine to paralic environments of deposition for the sedimentary units concerned.

The stratigraphy, age, depositional environment and correlation of the collision-related variegated sandstone and conglomerate beds exposed along the southern side of the Gangdise Mountains to the north of the Yarlung Zangbo suture in the Xigaze region, Xizang (Tibet) have been much debated. Generally referred to as the Dagzhuka Formation, these beds of great thickness have, until recently, not been reported to contain any convincing fossils. Two distinctly different palynological assemblages, indicating Late Cretaceous and Oligocene–Early Miocene ages respectively, have now been recovered from lithologically distinguishable units of the sedimentary succession at Qiabulin to the west of the town of Xigaze. This means that instead of one stratigraphic unit, as has been generally accepted hitherto, at least two are represented. As a result, the Dagzhuga Formation is considered here to refer only to the Cenozoic deposits and the Qiabulin Formation, previously regarded as a synonym, is resurrected to accommodate the Cretaceous beds. These two formations were juxtaposed by tectonic movements. Our finding indicates that the stratigraphic successions on the southern Laurasian continental margin of Xizang reflect changes from a deep forearc basin through shallow littoral environments to a mountainous landscape during the Late Cretaceous and early Cenozoic. This interpretation compares well with those documented from the Gamba and Tingri districts to the south of the Yarlung Zangbo suture.

Batten, D. J. (2009). An unusual megaspore of uncertain systematic affinity from Lower Cretaceous deposits in south-east England and its biostratigraphic and palaeoenvironmental significance. Grana, 48(4), 270-280.

A megaspore biozonation of the non-marine Åre Formation is proposed, based on a micropalaeontological analysis of key Haltenbanken area wells (Block 6608/11). The lower part of the Åre Formation is divisible into Banksisporites pinguis, Nathorstisporites hopliticus and Horstisporites areolatus zones, and subzones, occupying the Rhaetian–Hettangian interval. In the upper Åre Formation a marked turnover of megaspore assemblages is evident, with the appearance of several species of Trileites and the mesofossil Kuqaia quadrata. On this basis, the biozonation is extended into the Sinemurian–Pliensbachian, with the recognition of the Kuqaia quadrata Zone and subzones. Reference to selected wells in the Urd Field (Block 6608/10) and further south demonstrates that these biozones correlate across the northern Haltenbanken region. Biozonal boundaries are calibrated with miospore/microplankton markers where possible, to provide a robust bio-chronostratigraphical framework with which to evaluate the stratigraphy of the Åre Formation and its reservoir units. Comparison with published European biostratigraphical data shows that a similar megaspore succession exists through the Rhaeto-Liassic interval, with shifts in megaspore composition occurring within the same time intervals. On this evidence it is suggested that the megaspore biozones identified are regionally extensive and may reflect palaeoclimatic controls on the distribution of the megaspore-producing plants. It is concluded that megaspores are a stratigraphically important microfossil group, which should be utilized routinely in Upper Triassic–Jurassic oil field and regional biostratigraphical studies.

The spinicaudatan (conchostracan) Dictyestheria , originally recovered from the Yaojia Formation, is recognized to occur also in the basal part of the overlying Nenjiang Formation. This means that the Dictyestheria elongata ( = D . ovata ) Zone extends from the Yaojia Formation into the upper Turonian basal part of the First Member of the Nenjiang Formation and underlies the Halysestheria yui Zone at Yaojia Railway Station, Dehui City, Jilin Province, northeast China. The fossil record shows that the basal part of the Halysestheria yui Zone is dominated by Plectestheria songhuaensis in the study area. The diagnoses of Dictyestheria and Plectestheria are revised on the basis of an examination of specimens under a scanning electron microscope. In both genera the radial lirae on the growth bands near the umbo are long and relatively widely spaced. There is a fine reticulum between them in the umbonal part of the carapace and cross-bars occur on the ventral surface. The ornament of both genera indicates that they can be assigned to the family Halysestheriidae rather than to the Jilinestheriidae, in which they have been placed previously. The discovery of serration along the lower margins of growth lines in Plectestheria indicates its close relationship with Orthestheria ( Migransia ), supporting an interpretation of parallel evolution of O. ( Migransia ) to Plectestheria in East Asia and Bauruestheria in South America.

Li, G., Cheng, P., Wang, D., Batten, D. J. (2009). The spinicaudatan Tylestheria and biostratigraphic significance for the age of dinosaur eggs in the Upper Cretaceous Majiacun Formation, Xixia Basin, Henan Province, China. Cretaceous Research, 30 (2), 477-482.

A palynostratigraphic and palynofacies study of a geological section at Cuojiangding in Zhongba County has provided a basis for discussing the palaeoenvironmental evolution of the southern continental margin of Laurasia in Xizang (Tibet) towards the end of the Cretaceous Period and during the Paleogene. It is the only record of fossil spores and pollen grains from collision- and convergence-related sediments close to the major Yarlung Zangbo Suture. Deposits of the Padana Formation at the base of the section through the Qubeiya, Quxia, and Jialazi formations to the Rujiao Zangbo Conglomerate at the top are considered to range in age from Santonian to Eocene or possibly Oligocene. During this period the India plate collided with, and continued to push against, Laurasia plate. Two spore and pollen zones and three palynofacies types are recognized. These are correlated with two transgressive–regressive cycles associated with the collision, periods of geologically rapid uplift being reflected by the molasse-like sediments of the upper Quxia Formation and the Rujiao Zangbo Conglomerate, which accumulated during the Late Paleocene and Eocene–Oligocene respectively. The first regression led to intermittent subaerial exposure and erosion of the Cuojiangding area. The second ended the marine history of the area and led first to the development of swamps in a subtropical climate, now preserved in the coal-bearing Qiuwu Formation, and later to the development of mountainous terrain, with a cooler climate at higher elevations.

Palaeontology plays an indispensable role in interpreting the sedimentary and tectonic history of the convergence of India and Laurasia and its consequences. Hitherto, spores and pollen grains have not been used very much in this connection. In this paper, we consider the palynology of two sedimentary successions in Xizang (Tibet) that reflect the early stages of this convergence. One of these is near the town of Xigaze, in Xigaze County (the eastern site), and the other is in Zhongba County (the western site). The palynomorph assemblages from these sites are broadly comparable in being dominated by gymnosperm pollen taxa, especially Classopollis and Exesipollenites. Angiosperm pollen grains are more common at the eastern site, especially representatives of the genus Proteacidites. The assemblages are considered to be late Late Cretaceous (SantonianeMaastrichtian) in age and, in common with the lithologies from which they were recovered, reflect a hot, arid or semi-arid climate comparable to that prevailing in South China during this period. 2007 Elsevier Ltd. All rights reserved.

The diagnosis of the conchostracan genus Tenuestheria from the Lanxi Formation in Jinhua, Zhejiang Province in Southeast China is revised following an examination of the type species under a scanning electron microscope, which revealed some morphological features on the carapace that had not been recognized previously. The importance of the Tenuestheria Fauna is considered in the context of correlation of six Turonian-Santonian formations in this region of China. The value of the Cenomanian Nemestheria and Turonian Linhaiella faunas in correlating the underlying early Late Cretaceous formations is also noted.

In the Jixi Basin, eastern Heilongjiang Province, China, the lower part of the Lower Cretaceous succession consists of coal-bearing strata including the Muling Formation, which, in addition to plant megafossils, yields abundant spores and pollen grains and a few dinoflagellate cysts. The spore-pollen assemblage consists of more than 42 species belonging to 34 genera. Most of these are derived from pteridophytes and gymnosperms. The association of Aequitriradites echinatus , Cicatricosisporites australiensis , C. imbricatus , C. mediostriatus , C . undosus , Contignisporites glebulentus , Crybelosporites punctatus , Foraminisporis asymmetricus , Gleicheniidites laetus , Impardecispora purverulenta , Kuylisporites lunaris , Pilosisporites trichopapillosus and Triporoletes singularis suggests that the formation is unlikely to be older than late Hauterivian and younger than Aptian, with emphasis placed on the Barremian–early Aptian. The composition of the dinoflagellate cyst and plant megafossil assemblages is consistent with this determination. Based on palynofloral content, a comparison between the miospores recovered and the spores and pollen produced by extant plant taxa, the associated plant megafossils, and the sedimentary facies that characterize the Muling Formation, it is concluded that the source vegetation was dominated by ferns and that the climate was wet subtropical but seasonally dry.

Re-examination of specimens of the type species of Yanjiestheria (Y. bellula), from the Albian Dalazi Formation in eastern Jilin, and Yanshania (Y. dabeigouensis), from the Berriasian Dadianzi Formation in northern Hebei, under a scanning electron microscope has confirmed that Yanshania is a junior synonym of Yanjiestheria. This means that the earliest occurrence of Yanjiestheria precedes that of Eosestheria in northern Hebei, indicating that it cannot have descended from the latter, as has been suggested previously; rather the two genera must have evolved in parallel. An analysis of the changes in diversity of components of the Eosestheria fauna of the Jehol Biota indicates that the increase in the number of genera and species, which began during the deposition of the Jianshangou Beds of the Yixian Formation, may have been connected with the dispersal of conchostracan taxa to north-east China, Inner Mongolia, west and south Mongolia and elsewhere from what appears to have been their main centre of origin in northern Hebei. The Eosestheria fauna continued to flourish until deposition of the Jiufotang Formation came to an end. 2006 Elsevier Ltd. All rights reserved.