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Deep-water benthic foraminifera are investigated from Paleocene to Eocene sediments recovered from IODP Hole U1511B in the northeastern Tasman Sea. The recovered foraminifera display exceptional three-dimensional preservation: they are relatively unaltered by sediment diagenesis and compaction.We examined 33 samples from Cores U1511B-33R to -42R, and recovered 79 species of deep-water agglutinated foraminifera (DWAF) and 13 species of calcareous benthic foraminifera. The assemblage consists entirely of "cosmopolitan" forms originally described from the Carpathians, Caucasus, Trinidad, and the western Tethys, and other DSDP/ODP sites, implying that there is little or no endemism among deep-water benthic faunas in the semi-isolated Tasman Sea. The Paleocene--Eocene interval is characterized by successive acmes of Spiroplectammina, Trochammina, ammodiscids, and Karrerulina, and therefore bears striking similarity to previously studied sections in the western Tethys and Boreal North Atlantic. The taxonomic turnover among the DWAF is minor across the P/E contact, with only three apparent extinctions and three originations from the uppermost cores of the Paleocene and the lowermost cores of the Eocene. Calcareous benthic foraminifera were not observed in the Eocene samples, possibly a result of the shoaling of the CCD. [ABSTRACT FROM AUTHOR]

Changes in fire ecology during warm and cold periods in the geological past are important because of their effects on terrestrial ecosystems and the global carbon cycle. We examined the charcoal concentrations of the Erden Obo section in Inner Mongolia to reconstruct the evolution of wildfire and their relationship to the regional vegetation from the Late Paleocene through Early Oligocene. Our data show that fire frequency were relatively high from the end of the Paleocene to the beginning of the Eocene, in accord with other paleofire records worldwide. However, low fire frequency occurred during the Early Eocene Climate Optimum (EECO), coincident with the change in the regional vegetation from shrubland to forest due to the strengthening of the regional rainfall, and we suggest that the humid climate may have been responsible for this decrease. High frequency fire occurred after the Middle Eocene, near-synchronously with the transition ofthe regional vegetation from forest to steppe. The high-frequency fire was most likely triggered by regional drought during the aridification process after the Middle Eocene. We propose that these temporal changes in the fire ecology were consistent within the northern temperate zone from the Late Paleocene through Early Oligocene, and we suggest that studies of global wildfires need to be evaluated within the context of paleovegetation zones and ecosystem evolution. [ABSTRACT FROM AUTHOR]

A study was carried out in the Punjab Platform Basin located in Pakistan to evaluate the potential for hydrocarbon in the early Eocene and Paleocene sequences using petrophysical and geochemical techniques. The assessment of reservoir properties for the Sakesar Formation was carried out using wireline logs, which included measurements of water saturation, hydrocarbon saturation, and porosity. Moreover, 21 well-cutting samples were collected to assess the source rock potential of the Nammal (early Eocene), Dungan, and Ranikot (Paleocene) Formations. The results showed that the Nammal and Dungan Formation samples had low to moderate TOC content, ranging from 0.21 to 2.04 wt.% and 0.45 to 0.56 wt.%, respectively, while the Ranikot Formation samples had moderate to high TOC content, ranging from 0.48 to 1.63 wt.%. The formations under study were found to have a low potential for generating hydrocarbons, as indicated by their S2 values ranging from 0.21 to 2.04 mg HC/g rock. The primary type of kerogen present in these formations was type III and mixed type II/III kerogen, and several plots confirmed the poor generative potential of these formations. The analysis of the Sakesar Formation revealed that it had higher porosity levels at depths of approximately 4163–4197 ft4, with average porosity ranging between 8 and 14% and 68.28% SH and 31.71 Sw, indicating moderate to poor reservoir potential. These findings suggest that the Sakesar Formation could potentially be a moderate-to-good reservoir. [ABSTRACT FROM AUTHOR]

The importance of topography generated by Eocene Eurekan deformation as a sediment source for sandstones deposited on the western Barents Shelf margin is evaluated through a sediment provenance study conducted on wellbore materials retrieved from Spitsbergen and from the Vestbakken Volcanic Province and the Sørvestsnaget Basin in the southwest Barents Sea. A variety of complementary techniques record a provenance change across the Paleocene-Eocene boundary in wellbore BH 10-2008, which samples Paleogene strata of the Central Tertiary Basin in Spitsbergen. Sandstones containing K-feldspar with radiogenic Pb isotopic compositions, chrome spinel in the heavy mineral assemblage, and detrital zircons and rutiles with prominent Palaeoproterozoic and Late Palaeozoic—Early Mesozoic U-Pb age populations are up-section replaced by sandstone containing albitic plagioclase feldspar, metasedimentary schist rock fragments, a heavy mineral assemblage with abundant chloritoid, metamorphic apatite with low REE contents, metapelitic rutile with Silurian U-Pb ages and zircons with predominantly Archaean and Palaeoproterozoic U-Pb age populations. Our results clearly demonstrate the well-known regional change in source area from an exposed Barents Shelf terrain east of the Central Tertiary Basin during the Paleocene to the emerging Eurekan mountains west and north of the Central Tertiary Basin during the Eocene. Eocene sandstones deposited in the marginal basins of the southwestern Barents Shelf, which were sampled in wellbores 7316/5-1 and 7216/11-1S, contain elements of both the Eurekan and the eastern Barents Shelf provenance signatures. The mixing of the two sand types and delivery to the southwest margin of the Barents Shelf is consistent with a fill and spill model for the Central Teritary Basin, with transport of Eurekan-derived sediment east then south hundreds of kilometres across the Shelf. [ABSTRACT FROM AUTHOR]

Saniwa is an extinct genus of varanid squamate from the Eocene of North America and Europe. Up to now, only one poorly known species, Saniwa orsmaelensis Dollo, 1923, has been reported from Europe. Diagnostic material was limited to vertebrae with only preliminary description and no figure provided, except of one dorsal vertebra that was designated as the lectotype. New specimens from the earliest Eocene of Dormaal, Belgium and Le Quesnoy, France, including recently recovered skull material, are described and illustrated here. These fossils representing the oldest varanid squamate allow further comparisons with the type species, Saniwa ensidens Leidy, 1870, from the early and middle Eocene of North America and to propose a new diagnosis for S. orsmaelensis. Its arrival in Europe is probably linked to rapid environmental changes around the Paleocene Eocene Thermal Maximum (PETM). The occurrence of S. orsmaelensis is restricted to the early Eocene of northwest Europe and paleogeographic considerations regarding the distribution of the genus Saniwa Leidy, 1870 suggest an Asian origin, but an African origin cannot be completely excluded. [ABSTRACT FROM AUTHOR]

Among dinoflagellates, extant cladopyxidaceans may provide a missing link to better understand the first evolutionary transformations from ancestral configurations toward the more abundant and more derived patterns in Gonyaulacales and Peridiniales. A restudy of the extant, motile-defined Micracanthodinium setiferum using plankton samples from the Indian and Atlantic oceans and the Mediterranean Sea demonstrates that the correct plate formula is Po, Pt, X, 3′ + *4′, 4a, 7′′, 7C, 4S, ?6′′′, 0p, 2′′′′. A ventral pore is found between 1′, 3′ and *4′. A restudy of the extinct, fossil-defined Cladopyxidium saeptum from the upper Paleocene of Delaware (USA), demonstrated the presence of an identical tabulation. A ventral pore (= porichnion) was positioned between *1′ and 7′′. Cladopyxidium is morphologically closer to Micracanthodinium than to Cladopyxis. Since Cladopyxidium has been extinct since the middle Eocene, it is unlikely that Micracanthodinium and Cladopyxidium have a direct biological link; the close morphological similarity between them does, however, suggest an important phylogenetic relationship between them in the evolution of cladopyxidaceans. [ABSTRACT FROM AUTHOR]

Myanmar has a long history of petroleum production, but little information has so far been published pertaining to the detailed composition of the country's oils. The present paper reports the results of the analysis of a total of 28 Cenozoic oil samples collected from producing fields/wells or natural seepages in the onshore Salin and Chindwin Basins of the Central Myanmar Depression and from Ramree Island in the Rakhine Coastal Belt. In addition, a set of 68 mudstones and coals from four Oligocene – Paleocene formations were collected along the western margin of the Central Myanmar Depression and were analysed for petroleum generation potential. Data on five oil samples from the Assam Province of India, situated to the north of the Central Myanmar Depression, were also included in the study for comparison purposes. Previous studies have suggested that the Eocene succession in the Central Myanmar Depression includes organic‐rich source rocks. However, none of the analysed rock samples show any potential for the generation of appreciable amounts of liquid petroleum components. The samples were collected at the basin margin and only cover a small fraction of the succession, and they are probably not therefore representative of the actual source rocks present in deeply buried kitchen areas in the Central Myanmar Depression. The oils from the Central Myanmar Depression appear to have been generated from the same overall source type, which is dominated by terrigenous, higher land‐plant –derived kerogen. Several different parameters consistently show clear north–south trends in the Salin Basin with respect to both thermal maturity and source facies. Oils from the Chindwin Basin in the north of the depression can be distinguished from those of the Salin Basin further south using subtle variations in biomarkers. The oils collected from Ramree Island represent a different basin and are easily distinguished in that they are generated from a predominantly marine source rock, albeit one with a significant terrigenous input. However, one sample from Ramree Island was generated from a predominantly terrigenous source, which may suggest the existence of two viable petroleum systems in the Rakhine Coastal Belt or of marked facies variations within the source succession. Oils from the Central Myanmar Depression and the Assam Province of India are remarkably similar, thus suggesting generation from highly similar source rock types, presumably of Eocene age. This could be a result of these two areas being physically connected during the Eocene as suggested by modern plate reconstructions. [ABSTRACT FROM AUTHOR]

Through new palynological and chronostratigraphic (40Ar/39Ar dating) analyses we constrain the ages of important Australian Eastern Highland macrofloral sites. The Cambalong Creek site is late Paleocene (Selandian-Thanetian), with an age range of ∼ 57.3–59.8 Ma as inferred from palynostratigraphy (Proteacidites angulatus Subzone of the Lower Lygistepollenites balmei Zone). The Brandy Creek, Hotham Heights and Mount Buller sites are middle Eocene (Lutetian-Bartonian), with a minimum age of 39.58 ± 0.30 Ma, as inferred from 40Ar/39Ar analyses of overlying basalts, and a maximum age of ∼ 44 Ma inferred from palynostratigraphy (Lower Nothofagidites asperus Zone). The Kiandra Diggings site is early Miocene (Aquitanian), with a minimum age of 21.67 ± 0.26 Ma as inferred from 40Ar/39Ar dating and a maximum age of 23.03 Ma inferred from palynostratigraphy (Middle Proteacidites tuberculatus Zone). In the context of their revised ages, the recovered macrofloras suggest that subtropical climates prevailed during the late Paleocene (Cambalong Creek) and middle Eocene (Brandy Creek and Hotham Heights), whereas temperate climates existed during the early Miocene (Kiandra Diggings). For the middle Eocene sites, there is no discernible difference in paleotemperature estimates between lowland and highland sites, suggesting relatively low (< 550 m) paleoelevations for the present-day highland sites during the middle Eocene. This suggests that most of the present-day elevation (> 1400 m) was produced by post-middle Eocene uplift. • Ages of important Australian Eastern Highland macrofloral sites constrained. • Ages inferred through palynostratigraphy and 40Ar/39Ar analyses. • Subtropical climates in SE Australia during the late Paleocene and middle Eocene. • Similar temperature estimates for lowland and highland Eocene sites. • Present-day elevation (> 1400 m) produced by post-middle Eocene uplift. [ABSTRACT FROM AUTHOR]

The depositional sequence stratigraphy examination of the Paleocene-Eocene succession in Wadi Qena has been carried out based on the quantitative analysis of the nannofossil assemblages. Based on the lithostratigraphy, biostratigraphy, paleoecologic parameters (relative abundance of calcareous nannofossil, diversity indices of nannfossil, life strategies of calcareous nannofossil, Total Organic Carbon (TOC) and Calcium carbonate (CaCo3%), the temperature index (TI) of calcareous nannofossil, productivity indicators of calcareous nannofossil and sedimentation rate (SR). We detected six nannofossil biozones in the Paleocene-Eocene succession from NP4 to NP10 zones. The Se/Th boundary can be found in the NP7/8 Zone of the Hawashiya succession and the lower part of the NP9 Zone of the Abu Had succession. The P/E boundary is placed in the upper part of the NP9 Zone in the Hawashiya succession, and in the Abu Had sections, it coincides with the NP9/NP10 zonal boundary. These sea level falls compete well with the eustatic sea level drops that are only found in the Paleogene and are linked to tectonic events. In all, five stratigraphic sequences were recognized in the studied area. The first depositional sequence A (DS A) occurs within the nannofossil NP4 zone in the lower part of the Dakhla Formation, the second depositional sequence B (DS B) occurs in Fasciculithus tympaniformis (NP5) Zone in the Dakhla Formation, the third depositional sequence C (DS C) occurs between Heliolithus kleinpelli (NP6) and the lower part of the Discoaster multiradiatus (NP9) Zone, the fourth depositional sequence D (DS D) falls within the interval of Discoaster multiradiatus (NP9) Zone. It covers the Upper Paleocene part of the Esna Formation at Hawashiya and Abu Had sections, the fifth depositional sequence E (DS E) within the interval of the Tribrachiatus contortus Zone (NP10). It covers the Early Eocene (Ypresian) part of the Esna Formation (El Shaghab member) at Hawashiya and Abu Had sections. • Description of the depositional sequence stratigraphy of the Wadi Qena successions. • Decadal scale paleoenvironmental changes in Paleocene-Eocene successions. • Six nannofossil biozones and stage boundaries along the Paleocene-Eocene succession. • Deduce five stratigraphic sequences using palaeoecological parameters. • These sea level drops match well with the eustatic sea level. [ABSTRACT FROM AUTHOR]

Since its first description in 1960, the brachyuran crab genus Pleolobites was restricted to the Eocene (Ypresian) strata of Ivory Coast. Here, we report newly collected specimens that indicate its presence in the Paleocene (Thanetian) of Togo. This monotypic genus has been classified within various higher taxa, including Portunidae, Macropipidae, and Carcinidae, depending on the concurrent classification of portunoid crabs. Through the re-examination of the type material of Pleolobites erinaceus , the most recent assignment of Pleolobites within the subfamily Polybiinae of the family Carcinidae is disputed herein. Nevertheless, we refrain from assigning Pleolobites to any family and opine for its placement as Portunoidea incertae sedis. Additionally, the crab genus Rhachiosoma , morphologically similar to Pleolobites , is also removed from Polybiinae and placed in Portunoidea incertae sedis. It is further argued that Palaeoxanthopsis , Paraverrucoides , Parazanthopsis , and Verrucoides currently classified within the family Palaeoxanthopsidae of the superfamily Carpilioidea show striking similarities with Pleolobites and Rhachiosoma , including the morphology of dorsal carapace, thoracic sternum and pleon. Additionally, chelipeds with a spiny propodal margin and multi-lobed serial finger-teeth, otherwise characteristic for Portunoidea are found in Parazanthopsis and Palaeoxanthopsis. It remains to be investigated whether these resemblances are the result of evolutionary convergence or close phylogenetic relationships. add a blank line [ABSTRACT FROM AUTHOR]