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Here, the larger foraminifera found in Middle Eocene-Early Miocene rocks from Dhofar (Oman) and Socotra Island (Yemen) are studied in detail. The architectural analysis leads to the description of five new genera and nine new species: five agglutinated foraminifera, Pseudolituonella robineti n. sp., Socotraella ashawqi n. gen. n. sp., Pseudoaccordiella ayaki n. gen. n. sp., Barattolites andhuri n. sp., and Rogerella aydimi n. gen. n. sp.; and four porcellaneous foraminifera, Idalina grelaudae n. sp., Idalina pignattii n. sp., Macetadiscus incolumnatus n. gen. n. sp., and Omanodiscus tenuissimus n. gen. n. sp. The larger foraminifera identified in a composite section located in western Dhofar, in the Shuwaymiyah section located in eastern Dhofar, and in the Wadi Ayak section located on Socotra Island have facilitated the identification of the following larger foraminifera zones: SBZ 14-SBZ 15 (middle Lutetian), SBZ 16 (late Lutetian), SBZ 17 (Bartonian), SBZ 18 (latest Bartonian-earliest Priabonian), SBZ 19-SBZ 20 (Priabonian), SB 21-SB 22A (Rupelian), SB 22B-SB 23 (Chattian), and SB 24 (Aquitanian). All these data permit to assess the age of the following lithostratigraphic units: Dammam Fm.-Andhur Mb. lower Lutetian?-middle Lutetian age (SBZ 13?-SBZ 14 partim), Qara Mb. middle Lutetian (SBZ 14-SBZ 15), and Uyun Mb. upper Lutetian (SBZ 16); Aydim Fm.-Heiron Mb. Bartonian (SBZ 17), Moosak Mb. upper Bartonian-Priabonian (SBZ 18-SBZ 20), Tagut Mb. Priabonian (SBZ 19-SBZ 20), and Haluf Mb. Priabonian (SBZ 19-SBZ 20) to lower Rupelian (SBZ 21) on Socotra Island; Ashawq Fm. Rupelian (SB 21-SB 22A); and Mughsayl Fm. Chattian-Aquitanian (SB 23-SB 24). [ABSTRACT FROM AUTHOR]

Focuses on the chronostratigraphy of the middle Eocene-upper Eocene successions of the Pyrenean foreland basin. Correlation of magnetic polarity stratigraphy with stratigraphic sections recording Paleogene marine succession; Revision of the international standard time scales.

Peradectidae are Paleogene ‘opossum-like’ stem-metatherians, largely Laurasian, whose evolutionary history remains unclear. Based on new remains (mainly dental) discovered in several French localities, we carry out a comprehensive systematic revision of all early Eocene peradectids from Europe (~MP7 reference level to MP10-11 interval). We describe well-preserved specimens from Palette (Southern France, MP7-MP8 + 9 interval) documenting the earliest European peradectid, Peradectes crocheti sp. nov. This new species exhibits an interesting mosaic of characters, including plesiomorphic traits found in the North American type species, Peradectes elegans Matthew and Granger, 1921. Molars allocated to the strikingly ubiquitous Peradectes crocheti sp. nov. are found in eight additional localities from northwestern and southwestern Europe, all limited to the time interval MP7-MP8 + 9. Moreover, the study of unpublished material of the MP8 + 9 and ~MP8 + 9 peradectids allows us to recognize two younger coeval species (Peradectes louisi Crochet, 1979, and Peradectes russelli Crochet, 1979). Our taxonomic conclusions are supported a posteriori by the first quantitative assessment of the variation in height of metatherian stylar cusps. The holotype of Peradectes louisi is reinterpreted, and Peradectes ‘mutigniensis’ Crochet, 1979 appears to be a junior synonym of Peradectes russelli. In addition to size, the otherwise similar Peradectes louisi and Peradectes russelli can be distinguished based on subtle yet consistent differences, such as lower molar proportions. Phylogenetic analyses using a novel matrix of dental characters shed new light on the relationships among Eocene peradectids, confirming the paraphyly of Peradectes with respect to Armintodelphys and Mimoperadectes. Our results suggest a single dispersal from North America to Europe in the evolutionary history of peradectids, which likely occurred immediately after the Paleocene-Eocene Thermal Maximum, Peradectes crocheti sp. nov. being recovered as the earliest offshoot of the European clade. Scarce lower molars from the MP10 reference locality and ~MP10 localities analyzed within this constrained phylogenetic framework reveal a trend towards shrinking of the entoconid in the European lineage throughout the early Eocene. [ABSTRACT FROM AUTHOR]

Humans live with our geological heritage, which forms by multi-stage processes throughout the Earth’s geological history, cannot be uncovered or reconstructed by human influence and exists in a very delicate balance. Ardanuç (Artvin, Türkiye) district is a region with great potential for geotourism due to its natural, historical and cultural assets. However, there are currently no comprehensive studies that fully evaluate this strong geotourism potential. Throughout the study, the aim is to use both scientific and traditional approaches to preserve this heritage on a scientific basis and pass it on to future generations. Comparative and future conclusions can be drawn by mankind about the geological processes affecting the canyons and their significance today. The details and morphological features of the Cehennem Deresi Canyon(s), which developed in two different directions, and their value in different areas were determined. As a result, the research concludes with information about the conservation-use balance and suggestions for the future. [ABSTRACT FROM AUTHOR]

The results of a palynological study of the middle Eocene-lowermost Oligocene strata of the Shagap and Landzhar outcrop sections (southern Armenia) are presented. A series of stratigraphically important dinoflagellate cyst events were recognized in the uppermost Lutetian-lowermost Rupelian parts of the sections, including the lowermost occurrences of the key-species Rhombodinium draco, Schematophora speciosa, Hemiplacophora semilunifera, Hapsocysta kysingensis, Thalassiphora? cf. rota, Rhombodinium porosum, Glaphyrocysta semitecta, Reticulatosphaera actinocoronata, Stoveracysta ornata-group and Wetzeliella gochtii. Based on the first-order calibrations with calcareous nannoplankton and foraminifers, R. draco first occurs at the Lutetian-Bartonian transition, while the lowermost occurrence of R. actinocoronata is very close to the Bartonian-Priabonian boundary. The analysis of the ratios of palynogroups and dinoflagellate eco-groups permits to interpret the environmental conditions during the accumulation of regional formations: (1) a major marine transgression started at the beginning of the Lutetian and the gradual deepening of the marine basin occurred during the middle-late Lutetian (Arpa Formation); (2) the marine transgression, accompanied by deepening, continued during the early Bartonian, but towards the end of the Bartonian slightly shallower depositional conditions were established (Azatek Formation); (3) the sea continued to gradually become shallower during the Priabonian (Urtsadzor Formation) and, finally, the maximum of regression was observed at the Eocene-Oligocene transition, ending with the establishment of brackish environments at the beginning of Rupelian (Shagap Formation). [ABSTRACT FROM AUTHOR]

We document the stratigraphy, lithofacies and depositional environment of the lower Eocene-lower Oligocene Nisai Group, based on petrographic and micropaleontological analysis, and field observations. We rename the whole sedimentary succession as the Nisai Group and divide it into three formations, from bottom to top; Jabrai, Torkhezhe Tsah and Nisai formations. The Jabrai Formation comprises a thick succession of olive gray mudstone and shales with subordinate sandstone, limestone and quartzose conglomerate, interpreted as deltaic and littoral deposits. The Torkhezhe Tsah Formation comprises calciturbidites in its lower part and periplatform oozes and basinal shales in upper part. The shallow-marine carbonate material of calciturbidites possibly derived from a lost platform which was a narrow delta-top-platform developed over deltaic sediments of the Jabrai Formation. The uppermost unit, the Nisai Formation, comprises thick bedded limestone with subordinate shale and nodular reefoid limestone, and shows a shallowing-up succession overlying the slope and basinal deposits of the Torkhezhe Tsah Formation. The presence of Cr-rich spinels in sandstone of the Jabrai Formation, ultramafic-mafic and quartzite lithoclasts in calciturbidite beds as well as paleocurrent data, suggest that siliciclastic sediments of the Nisai Group derived from the Zhob Valley Ophiolites. Moreover, the presence of quartz, igneous and metamorphic extraclasts, and dolomitic horizons within calciturbidite beds, indicate deposition of these calciturbidites in response to lowering of sea level. We propose that emplacement of Zhob Valley Ophiolites served as a drainage divide and supplied deltaic sediments to the Jabrai Formation to its north and the Ghazij Group to the south. [ABSTRACT FROM AUTHOR]

This paper contributes to an understanding of the tectono‐sedimentary evolution of the South Pyrenean foreland system by reviewing the chronostratigraphic framework of the basin infill in its eastern sector. Six sections are analysed and cross‐correlated to build a 6.5 km thick composite magnetostratigraphy that represents the complete record of the Cadí Nappe in the Ripoll Syncline. New and previous magnetostratigraphic sections are integrated with available biostratigraphy to provide a new age calibration of the sedimentary succession of the Cadí Nappe, encompassing from Palaeocene to Middle Lutetian age. The proposed correlation with the Geomagnetic Polarity Time Scale aims at best reconcile magnetostratigraphic data with the regional biochronology built on the marine Shallow Benthic Zonation (SBZ biozones), the continental mammalian biochronology (MP levels) and the newly collected charophyte data. A subsidence analysis was performed on the calibrated composite succession, resulting in two well‐defined intervals bounded by a hiatus. A Palaeocene to Early Eocene interval with low (11–21 cm/kyr) total subsidence rates, and an Early to Middle Eocene interval, characterised by high (70–75 cm/kyr) total subsidence rates. The detailed trends in both subsidence and sedimentation mark the development and evolution of the foreland depozones, from distal foreland depozones to foredeep and wedge‐top depozones, relative to the emplacement of the Pedraforca Nappe and Cadí Thrust Nappe. The most pronounced sedimentary shift in the Cadí Nappe occurred at 49 Ma, with the rapid drowning of the carbonate platforms and its transition into talus and deep basinal environments. Carbonate platforms collapsed and resedimented on the talus of the elongated trough, newly formed parallel to the orogenic front. This marked the onset of tectonic subsidence triggered by the submarine emplacement of the Lower Pedraforca Nappe. The emersion of the orogenic wedge drove the entry of siliciclastics, lagged by 1 Myr, into the Ripoll Trough. The foredeep filled rapidly (5.5 km thickness in less than 7 Myr) compared to other South Pyrenean regions, favoured by its semi‐enclosed palaeogeography. The emplacement of the Vallfogona Thrust as early as the Middle Lutetian (43 Ma) brought the Cadi Nappe into a wedge‐top setting. However, the Ripoll growth syncline continued acting as a temporary sink for alluvial sedimentation while a foredeep developed further south in the autochthonous Ebro Basin. The flexural response of the Iberian plate to the tectonic thickening of the Axial Zone counterbalanced for a period the local uplift of the Cadi Nappe, providing accommodation space for the top sediments filling the Ripoll Syncline. [ABSTRACT FROM AUTHOR]