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We used high-resolution 3D seismic data and applied seismic attribute analysis to geometrically interpret and characterize the polygonal fault systems in the Paleocene-Eocene sequence of the Rankin Platform Sub-basin, Northern Carnarvon Basin, Australia. The polygonal faults were identified in a stratigraphic sequence dominated by calcareous clay with minor calcilutite at its lower section that changes to argillaceous calcilutite and calcareous claystone at its upper section. Seismic sections and time slices, through multi-attribute (coherence, energy ratio similarity, and curvature) volumes display a dense distribution of normal faults with polygonal shape and small throws in the plain view. The polygonal fault systems (PFS) exist in two well-defined tiers, which can act as pathways for the fluid flow migration. The first tier coincides with the upper section (Early-Middle Eocene Wilcox Formation) with a few faults and the second one coincides with the lower section of the sequence (Paleocene Lambert and Dockrell formations) with a greater number of faults. Proper understanding and interpretation of the polygonal fault systems as non-tectonic extensional faults are a critical issue in assessing the migration pathway for hydrocarbon (gas) through the Paleocene-Eocene sequence in the Northern Carnarvon Basin, and elsewhere in the world. [ABSTRACT FROM AUTHOR]

• Background and Aims Early Palaeocene (Danian) plant fossils from Patagonia provide information on the recovery from the end-Cretaceous extinction and Cenozoic floristic change in South America. Actinomorphic flowers with eight to ten perianth parts are described and evaluated in a phylogenetic framework. The goal of this study is to determine the identity of these fossil flowers and to discuss their evolutionary, palaeoecological and biogeographical significance. • Methods More than 100 fossilized flowers were collected from three localities in the Danian Salamanca and Peñas Coloradas Formations in southern Chubut. They were prepared, photographed and compared with similar extant and fossil flowers using published literature and herbarium specimens. Phylogenetic analysis was performed using morphological and molecular data. • Key results The fossil flowers share some but not all the synapomorphies that characterize the Schizomerieae, a tribe within Cunoniaceae. These features include the shallow floral cup, variable number of perianth parts arranged in two whorls, laciniate petals, anthers with a connective extension, and a superior ovary with free styles. The number of perianth parts is doubled and the in situ pollen is tricolporate, with a surface more like that of other Cunoniaceae outside Schizomerieae, such as Davidsonia or Weinmannia. • Conclusions An extinct genus of crown-group Cunoniaceae is recognized and placed along the stem lineage leading to Schizomerieae. Extant relatives are typical of tropical to southern-temperate rainforests, and these fossils likely indicate a similarly warm and wet temperate palaeoclimate. The oldest reliable occurrences of the family are fossil pollen and wood from the Upper Cretaceous of the Antarctica and Argentina, whereas in Australia the family first occurs in upper Palaeocene deposits. This discovery demonstrates that the family survived the Cretaceous-Palaeogene boundary event in Patagonia and that diversification of extant lineages in the family was under way by the earliest Cenozoic. [ABSTRACT FROM AUTHOR]

A new find is identified as a representative of the subfamily Spinilomatinae, viz. Spiniloma? faxensis sp. nov. The specimen was found as an impression in coral limestone of the early Paleocene (middle Danian) Faxe Formation in the Faxe quarry in Denmark. The genus Spiniloma was until now known exclusively from the Mesozoic of Europe. The new find extends the stratigraphic range of the genus into the early Paleocene. Furthermore, the gastropod fauna of the Faxe Formation is dominated by gastropods with a preference for hard substrates, while soft- substrate genera like Spiniloma are extremely rare. [ABSTRACT FROM AUTHOR]

In order to improve the reliability and accuracy of source rock evaluation, a total of 102 shale samples of Çamalan Formation were collected, analyzed and re-characterized with taking matrix retention effect into account. Results from Rock-Eval and visual kerogen analyses indicate: 1. an excellent source rock with an average TOC of 6.39 wt.%. 2. An assemblage of amorphous (i.e., alginite, type I) organic matter as a major organic constituent with an excellent potential for generating oil. 3. Shale samples from Çamalan Formation are in immature/early–intermediate stage of maturity based on T max (Avg. ∼440 °C) and spore color index (SCI ∼2.5–4). Also no amount of Çamalan generated oils are migrated out of shale based on S 1 vs. TOC plot. (i.e., Transformation ratio (TR ∼0)). Samples of this study show a significant mineral matrix effect. After correction of mineral matrix effect the average hydrogen index (HI) of the Çamalan Formation increased by more than 60 mg HC/g TOC and reached to an average of 811 mg HC/g TOC. Gas oil ratio potential (GORP) factor were used in order to split up the TOC and S 2 into oil-prone and gas-prone and also to investigate the level of consistency between the results of GORP factor and those of visual kerogen studies. Based on obtained GORP factor more than 90% of TOC (live) is composed from oil-prone materials which is in acceptable agreement with petrographic assessments. [ABSTRACT FROM AUTHOR]

The wood of Oleoxylon deccanense, reported informally in 1981 from the Deccan Intertrappean Beds of central India, is re-examined. We provide a formal diagnosis for the species and a more detailed description. The similarity to wood from species groups of the modern genera Chionanthus and Olea leads us to infer that this fossil taxon probably belongs to the monophyletic drupaceous subtribe Oleinae of the olive family, Oleaceae (Lamiales), although affinities with Rhamnaceae and Rutaceae cannot be wholly excluded. Since the fossil is from a late Maastrichtian-Danian horizon (65-67 MY BP) this would imply that a member of the Oleaceae was part of the flora that inhabited India several million years prior to the tectonic impact of India with Asia. The seemingly modern appearance of this and other Deccan fossil woods is briefly discussed. [ABSTRACT FROM AUTHOR]

Extant Neotropical rainforests are well known for their remarkable diversity of fruit and seed types. Biotic agents disperse most of these disseminules, whereas wind dispersal is less common. Although wind-dispersed fruits and seeds are greatly overshadowed in closed rainforests, many important families in the Neotropics (e.g., Bignoniaceae, Fabaceae, Malvaceae, Orchidaceae, Sapindaceae) show numerous morphological adaptations for anemochory (i.e. wings, accessory hairs). Most of these living groups have high to moderate levels of plant diversity in the upper levels of the canopy. Little is known about the fossil record of wind-dispersed fruits and seeds in the Neotropics. Six new species of disseminules with varied adaptations for wind dispersal are documented here. These fossils, representing extinct genera of Ulmaceae, Malvaceae, and some uncertain families, indicate that wind-dispersed fruit and seed syndromes were already common in the Neotropics by the Paleocene, coinciding with the early development of multistratal rainforests. Although the major families known to include most of the wind-dispersed disseminules in extant rainforests are still missing from the Paleogene fossil record of South and Central America, the new fossils imply that anemochory was a relatively important product and/or mechanism of plant evolution and diversification in early Neotropical rainforests. [ABSTRACT FROM AUTHOR]

Palynological investigation of the Upper Cretaceous–lower Paleocene succession from the Tahar section near Arba Ayacha in northwestern Morocco (westernmost External Rif Chain) reveals the presence of rich, diverse and well-preserved dinoflagellate cyst assemblages. For the first time in the study region, biostratigraphic interpretations based on the dinoflagellate cyst assemblages from the studied interval allow the recognition of the upper Maastrichtian and Danian. Relevant upper Maastrichtian–Danian global dinoflagellate cyst events include: the First Appearance Datum of the upper Maastrichtian species Disphaerogena carposphaeropsis , Glaphyrocysta perforata , and Manumiella seelandica ; the Last Appearance Datum of the Cretaceous taxa Dinogymnium spp., Isabelidinium cooksoniae , and Pterodinium cretaceum ; and the First Appearance Datum of the earliest Danian markers Carpatella cornuta , Damassadinium californicum , Membranilarnacia ? tenella , and Senoniasphaera inornata . We formally describe the biostratigraphical range and potential of two new dinoflagellate cyst species, namely Nematosphaeropsis silsila Guédé and Slimani nov. sp., and Pterodinium ayachensis Guédé and Slimani nov. sp. Both species are found in the westernmost External Rif Chain and are restricted to the upper Maastrichtian. [ABSTRACT FROM AUTHOR]

Abstract: The Late Cretaceous foraminiferal assemblages from five wells drilled in the southwestern Barents Sea were analysed using morphogroup analysis in order to understand the palaeoenvironment and palaeobathymetry of the study area. Morphogroup analysis of assemblages in the Upper Cretaceous Kveite Formation suggests stable, possibly middle to lower bathyal, mesotrophic and relatively well-oxygenated environments in the Tromsø Basin during the Late Cretaceous. The depositional setting of Upper Cretaceous Kviting Formation in the tectonically more stable Hammerfest Basin was probably shallower, but still represents a deep-water environment similar to that of the Kveite Formation. A shallowing regional bathymetry in the southwestern Barents Sea is indicated by the general decreasing trend in the relative abundance of tubular forms and the species diversity of assemblages, which reflects the regional Late Cretaceous–Paleocene uplift prior to the break-up of the Greenland–Norwegian Sea. Changes in the relative abundance of morphogroups and in the main constituent in the cumulative length of tubular taxa from Rhizammina to Rhabdammina near the top of Kveite Formation agree with the possible existence of bottom water currents. [Copyright &y& Elsevier]

Abstract: Extant Berberis is a member of the basal eudicots with a South America (group Australes)-Old World (group Septentrionales) disjunctive distribution pattern. Different hypotheses have been proposed to explain the formation of this pattern. Recent molecular studies suggest that this pattern was caused by a vicariance event in the Cretaceous. More fossil evidence is required to evaluate these hypotheses. Here a new species of Berberis from the Palaeocene Wuyun flora is established based on a detailed comparison with all other fossil and related living Berberis. The occurrence of a Palaeocene Berberis in NE China and other fossil data suggest that 1) the genus originated in eastern Asia, 2) the leaf venation of the genus probably evolved from pinnate to acrodromous, leaf margins from densely spinose teeth to only occasionally toothed or even entire, 3) the genus would appear to have migrated from eastern Asia to North America in the Oligocene, via Beringia. Berberis probably arrived in Europe from Asia during the late Oligocene when Eurasia was reunited after the retreat of the Turgai Straits. Berberis could have migrated to India from eastern Asia, arriving before the last major upheaval of the Himalayas in the Pleistocene. [Copyright &y& Elsevier]

Abstract: A detailed study of the calcareous nannofossil assemblages of latest Danian to early Selandian age from Wadi Qena (the Qreiya-1, Qreiya-2, and Araas sections) in the central Eastern Desert and the Gebel Duwi section at the Red Sea Coast has been carried out to understand the local phytoplankton paleocommunities. For the first time in Egypt four calcareous nannofossil zones (NTp6, NTp7, NTp8, NTp9) and five subzones (NTp7A, NTp7B, NTp8A, NTp8B and NTp8C) were distinguished subdividing the standard NP4 and NP5 zones. The calcareous nannofossil zones were correlated with nannofossil zonations from the Tethyan region (e.g. Tunisia and the Zumaia section, the GSSP for the Danian/Selandian boundary). The calcareous nannofossil assemblages are moderately to well preserved. The event beds are characterized by a dark-brown shaley-marl bed rich in organic carbon and coprolites. Three main assemblages are distinguished: a pre-event assemblage, a transitional assemblage and a post-event assemblage. The paleoenvironments vary from cool eutrophic water below and above the event to warm oligotrophic conditions during the event. The result of this study concludes that the “Latest Danian Event” (LDE) may represent an early Paleocene hyperthermal. [Copyright &y& Elsevier]

The Icacinaceae occur pantropically today, but are well represented by fossil fruits of the warm Early Middle Eocene, when tropical plants that currently occupy low latitudes were more widely distributed in higher latitudes. Members of this family are first known in the Late Cretaceous; however, fossil fruits of tribe Iodeae are quite rare before the Eocene. In this paper we describe the first formally recognized Late Paleocene icacinaceous taxa from western North America. We name two new species of Icacinicarya based on anatomically preserved fruits and establish a new genus, Icacinicaryifes, for impressions with a strong similarity to icacinicarya that lack anatomical preservation. These new records from the Almont/Beicegel Creek flora in North Dakota and several localities in Wyoming, Colorado, and Montana complement records known from the Early Eocene of England and document an increased diversity of Iodeae and related forms in the Paleogene of western North America. [ABSTRACT FROM AUTHOR]

Studies the platanaceous affinity of trifoliolate leaves of Platanus bella (Heer) comb.n. from the Paleocene of North America, Greenland and Asia. Relationships between Paleocene trifoliolate leaves with extinct and extant Platanaceae; Leaf epidermal structure; Cospecific status of populations.

Organic geochemical and palynofacies analyses were carried out on shale intervals of the Late Paleocene Patala Formation at Nammal Gorge Section, western Salt Range, Pakistan. The total organic carbon content and Rock-Eval pyrolysis results indicated that the formation is dominated by type II and type III kerogens. Rock-Eval Tmaxvs. hydrogen index (HI) and thermal alteration index indicated that the analysed shale intervals present in the formation are thermally mature. S1 and S2 yields showed poor source rock potential for the formation. Three palynofacies assemblages including palynofacies-1, palynofacies-2 and palynofacies-3 were identified, which are prone to dry gas, wet gas and oil generation, respectively. The palynofacies assessment revealed the presence of oil/gas and gas prone type II and type III kerogens in the formation and their deposition on proximal shelf with suboxic to anoxic conditions. The kerogen macerals are dominated by vitrinite and amorphinite with minor inertinite and liptinite. The kerogen macerals are of both marine and terrestrial origin, deposited on a shallow shelf. Overall, the dark black carbonaceous shales present within the formation act as a source rock for hydrocarbons with poor-to-moderate source rock quality, while the grey shales act as a poor source rock for hydrocarbon generation. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study `A Spirodela-like plant from the Paleocene Joffre Bridge locality,' by Georgia L. Hoffman et al. and presented during the 1995 Annual Meeting of the Botanical Society of America.