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Foraminiferal studies of the Mishan Formation in southern Iran have mostly used thin sections, with fewer studies of isolated forms. In this research, isolated foraminifera from early to middle Miocene beds (Mishan Formation) hsave been studied. The Mishan Formation comprises two members; the Guri member consists of limestones and marly limestones with medium layers of green marl; the marly member comprises green marls and grey marls with interlayered limestones. In this study, 120 samples were taken from marly members of Mishan Formation at four locations (i.e., Khorgu, Gery Sheikh, Roydar, and Baghestan) in Southern Iran. The total thickness of marl members in four outcrops are 1390. They yielded 46 genera and 53 species of benthonic foraminifera, and 8 genera and 13 species of planktonic foraminifera. In this research, 23 genera and 33 species have been described, many of which have not been reported from the Miashan Formation in Southern Iran. [ABSTRACT FROM AUTHOR]

End of 21st‐century hydroclimate projections suggest an expansion of subtropical dry zones, with Mediterranean and Sahel regions becoming much drier. However, paleobotanical assemblage evidence from the middle Miocene (17‐12 Ma), suggests both regions were instead humid environments. Here we show that by modifying regional sea surface temperatures (SST) in an Earth System Model (CESM1.2) simulation of the middle Miocene, the increased ocean evaporation and integrated water vapor flux overrides any drying effects associated with warming‐induced land‐surface evaporation driven by atmospheric CO2 concentrations. These modifications markedly reduce the bias in the model‐data comparison for this period. A vegetation model (BIOME4) forced with simulated climatologies predicts both regions were dominated by mixed forest, which is largely consistent with the paleobotanical record. This study unveils the potential for wetter subtropical Mediterranean climates associated with warming, presenting an alternative scenario from future drying projections with localized SST warming governing regional climate change. Plain Language Summary: Climate models project drier conditions over Europe and Northern Africa due to global warming. However, evidence from a past warm climate period, the middle Miocene (∼15 million years ago), finds wetter rather than drier environments. We refine climate model boundary conditions by reconstructing warmer ocean waters in the North Atlantic based on proxy evidence. The warmer ocean produces wetter environments by enhancing North Atlantic precipitation events and the North African monsoon. The increased rainfall and surface temperature cause a vegetation model to predict more forest coverage over Europe and Northern Africa, which is consistent with fossil evidence from ∼15 million years ago. This study unveils the potential for wetter climates associated with warming, presenting an alternative scenario from future drying projections, with localized sea surface warming governing regional climate. Key Points: Middle Miocene Europe rainfall discrepancy between herpetological (dry) and paleobotanical (wet) records complicate climate model validationSimulations that produce dry environments also produce cool North Atlantic sea surface temperatures which are inconsistent with proxiesSSTs informed by North Atlantic proxies produce wetter environments consistent with paleobotanical evidence [ABSTRACT FROM AUTHOR]

Prosantorhinus is a genus of small extinct teleoceratine rhinoceroses with shortened limb bones, widely distributed in Europe. However, the Asian evolution of the teleoceratine Prosantorhinus has remained unclear because of a scarcity of fossil records of the genus. Here, we report the first record of Prosantorhinus in East Asia from the Middle Miocene of Tongxin, Ningxia. The new specimen is characterized by a concave dorsal skull profile and elevated nasals; short and stout nasal bones with drooping margins on both sides; the thickened, enlarged, and roughened nasal extremity supporting a small horn; the semi-molarized upper premolars with a lingual bridge between the protocone and hypocone; the metaloph constriction present on P2–4; the protocone equal to the hypocone on P2; the crista present on P3; and the cement on the cheek teeth developed. With all the morphological evidence considered, we establish a new species, Prosantorhinus yei sp. nov.. A phylogenetic analysis based on 282 morphological characters scored for 36 taxa reveals that Prosantorhinus yei sp. nov. is a relatively derived taxon in the genus. We hypothesize that Prosantorhinus yei sp. nov. lived in relatively moist environments. [ABSTRACT FROM AUTHOR]

The Middle Miocene is characterized by a long‐term increase in the stable oxygen isotopic composition of benthic foraminifera (δ18Obenthic). However, it is unclear to what extent this increase reflects changes in seawater isotopic composition or deep water temperature. We present a high‐resolution alkenone hydrogen isotope (δ2HC37) record of the Middle Miocene from a core taken at the upper slope edge (about 409 m water depth) of the Porcupine Basin continental margin in the eastern North Atlantic Ocean, Site U1318 of the Integrated Ocean Drilling Program. The δ2HC37 values vary between −174 and −200‰ with an average of −191 ± 5‰, similar to modern open‐ocean values. Importantly, they do not show a long‐term increase in surface seawater isotopes (δ2HSSW) during the Middle Miocene Climate Transition. Indeed, when δ18Obenthic is corrected for subsurface temperature, the bottom seawater oxygen isotopes (δ18OBSW) show no significant increase in this period. When the latter record is translated into the hydrogen isotopic composition of bottom seawater using the modern open‐ocean waterline, it has an average value of 5.8 ± 1.5‰, similar to the δ2HSSW of 5.2 ± 3.1‰ derived from δ2HC37:2, suggesting a relatively small difference between bottom and surface waters. Our results suggest a stable global surface seawater isotope evolution during the Middle Miocene, coupled with a long‐term decrease in bottom water temperature. Key Points: No change in stable hydrogen isotopes of surface waters during the Middle Miocene Climate Transition period based on long chain alkenonesBottom seawater isotopes based on corrected oxygen isotopes of benthic foraminifera also show no long‐term change during the MMCTMiocene isotope events are reflected by only small δ18O and δ2H changes [ABSTRACT FROM AUTHOR]

Objective The middle Miocene submarine fan in the Qiongdongnan Basin is an important target for natural gas exploration in the northern South China Sea. However, there has been no consensus on the source of submarine fan sediments for a long time. Provenance analysis will be important for the optimization of natural gas exploration in this area. Methods In this paper, the detrital zircon U-Pb age spectrum characteristics of drilling cores from the middle Miocene submarine fan in the Qiongdongnan Basin were analysed and compared with the U-Pb ages of zircons from potential provenance areas to determine the source of submarine fans in the study area. Results The results show that ① the U-Pb ages of detrital zircons from the N-1, N-2, N-3 and N-4 wells in the northern part of the basin are characterized by Yanshanian (160, 157, 133, 107, 102, 99 Ma), Indosinian (249, 241, 239 Ma) and Caledonian (466, 455 Ma) age peaks and have high similarity with the U-Pb age characteristics of detrital zircons from Hainan Island sediments but low similarity with the U-Pb age characteristics of detrital zircons from Red River and central Vietnam sediments. ② The detrital zircon U-Pb ages of three wells (S-1, S-2, and S-3) in the southern part of the basin show peak ages of Caledonian (435, 431, 425 Ma), Hercynian (396, 392 Ma), Indosinian (242, 238, 237 Ma), and Yanshanian (143 Ma). The S-2 well has a younger unimodal Himalayan (21 Ma) age peak. Conclusion The provenance of the middle Miocene in the northern part of the basin is Hainan Island. The influence of the provenance on the Red River and Central Vietnam is very limited. The provenance of the middle Miocene in the southern Qiongdongnan Basin was a double-source supply from the Red River and Hainan Island and was dominated by the former, with an obvious difference from west to east.

An association of eighteen coprolites (specimens 01–18) and one isolated coprolite (specimen 209,210) were found in a vertebrate fossil-rich paleosol at the Gratkorn site (south-eastern Austria; late Middle Miocene). The specimens consist mostly of calcium phosphate (apatite) and a matrix formed by microglobules. Coprolites 01–18 show cylindrical and spherical morphologies and are considerably smaller than the tube-shaped specimen 209,210, in which no inclusions were observed. In contrast, coprolites 01–18 contain numerous, highly altered bone fragments (sub-mm-sized long bones and several mm-sized trabecular bone remains) as well as hair imprints, plant detritus and palynomorphs. Based on composition, morphology, size, microstructure, and inclusions, and considering the body fossil record of this site, we assume the hyaenid Protictitherium and the barbourofelid Albanosmilus, as producers of coprolites 01–18 and 209,210, respectively. The preserved bone remains in specimens 01–18 suggest that Protictitherium fed on small vertebrates, but possibly also cracked bones of medium-sized animals. The hair imprints found were either from the hyaenid itself or its prey, while the plant material was probably ingested accidentally. The lack of inclusions in specimen 209,210 is related to the presumably hypercarnivorous diet of Albanosmilus, which was certainly the apex predator in this biome. [ABSTRACT FROM AUTHOR]

High latitude metatherians from the Middle Miocene of Patagonia (Argentina and Chile) are only known from medium-sized Sparassodonta, and undescribed taxa collected in several fossil localities of Collon Cura (Argentina) and Río Frías (Chile) Formations, although the latter has several species reported and mostly recognised for the slightly older Santa Cruz Formation. In this contribution we describe five new genera and six new species of metatherians from Collon Cura Formation at Cerro Zeballos, Chubut province (Argentina), based on 11 specimens that notably increased the diversity of Collon Cura Formation. The specimens were assigned to the orders Paucituberculata (Palaeothentoidea), Sparassodonta (Hathliacynidae), and Polydolopimorphia (Argyrolagidae), and are taxa of small size, including the smallest palaeothentoids known to date. Also, the Palaeothentoidea of Cerro Zeballos are amongst the youngest of the superfamily in Patagonia. The new specimens described herein show morphological differences with other metatherian associations already known, probably related to adaptive changes coincident with the Middle Miocene Climatic Transition and the beginning of a faunal turnover. [ABSTRACT FROM AUTHOR]

Ocna Dej is an iconic locality for salt mining in Transylvania, being located in the north - north-western area of the Middle Miocene sedimentary basin of Transylvania. In this salt the fossils are rare and refer strictly to plant remains (fragments of wood, pine cones, etc.). A sample of charred wood collected from the area of Ocna Dej salt deposit of Middle Badenian age (Wielician) was submitted to a microscopic study for a taxonomic assignation. It was identified as Cupressinoxylon sp. aff. Thujoxylon sp. as a remain of the synchronous vegetation. This wood type is found for the first time in Ocna Dej salt and could contributes to the paleo-environmental reconstruction of this area. Obviously, wildfires occurred at that time around the marine sedimentary basin of Transylvania. [ABSTRACT FROM AUTHOR]

V.V. Bogachev (1933) described the scombrid fish Auxis caucasica based on an incomplete skeleton from the Sarmatian (Middle Miocene) of the North Caucasus (Stavropol Region). Subsequently, this species was assigned to the mackerel genus Scomber. New findings in the Sarmatian of the North Caucasus (Krasnodar Region, Pshekha River) revealed a significant reduction in the number of vertebrae in S. caucasicus (Bogatshov) (up to 28), which is extremely unusual for Scombridae, with at least 31 vertebrae. A new genus Mioscomber is established to accommodate the Sarmatian species of scombrids. The scombrids from the Sarmatian of the former Yugoslavia, originally described as Auxis vrabcensis Kramberger, 1882, A. thynnoides Kramberger, 1882 and Scomber sujedanus Steindachner, 1860, are assigned to the same genus—these also have a reduction in the number of vertebrae. The generic character of Mioscomber gen. nov. assumes correction of the diagnosis of the family Scombridae, from "Vertebrae 31–66" to "Vertebrae 28–66". [ABSTRACT FROM AUTHOR]

Deepwater oil and gas exploration is the key to sustainable breakthroughs in petroleum exploration worldwide. The Central Canyon gas field has confirmed the Lingshui Sag is a hydrocarbon-generating sag, and the deepwater reservoirs in the Lingshui Sag still have more fabulous oil and gas exploration potential. Based on drilling data and three-dimensional (3D) seismic data, this paper uses seismic facies analysis, seismic attribute analysis, and coherence slice analysis to identify the types of submarine fans (lobe-shaped and band-shaped submarine fans) that developed in the Lingshui Sag during the Middle Miocene, clarify the source-to-sink system of the submarine fans and discuss the genesis mechanism of the submarine fans. The results show that: (1) the deepwater source-to-sink system of the Lingshui Sag in the Middle Miocene mainly consisted of a "delta (sediment supply) - submarine canyon (sediment transport channel) - submarine fan (deepwater sediment sink)" association; (2) the main factor controlling the formation of the submarine fans developed in the Lingshui Sag was on the relative sea level decline; and (3) the bottom current reworked the lobe-shaped submarine fan that developed in the northern Lingshui Sag and formed the band-shaped submarine fan with a greater sand thickness. This paper aims to provide practical geological knowledge for subsequent petroleum exploration and development in the deepwater area of the Qiongdongnan Basin through a detailed analysis of the Middle Miocene submarine fan sedimentary system developed in the Lingshui Sag. [ABSTRACT FROM AUTHOR]

We name a rare, hypercarnivorous and durophagous mustelid Sonitictis moralesi, new genus and species, in honour of Jorge Morales for his contributions to carnivore palaeontology. Sonitictis moralesi is from the middle Miocene Tunggur Formation of Inner Mongolia, China (Tunggurian Land Mammal age). S. moralesi has a short and robust jaw that deepens slightly behind the m1 and possesses a shallow groove at its ventral surface. Dentally, it has robust premolars and highly hypercarnivorous m1 that has lost the metaconid and a trenchant talonid. Known by three jaw fragments, knowledge of this new mustelid is still poor and its relationship uncertain. However, based on its possession of a ventral groove, robust premolars and hypercarnivorous first molar, we tentatively place it in the subfamily Mellivorinae, which includes modern Mellivora capensis (honey badger) and extinct species of Eomellivora, plus others. We conducted mandibular force profile analyses on one S. moralesi specimen and compared bite force estimates to several specimens of E. piveteaui, E. wimani and M. capensis. The results suggest that Sonitictis likely was a more capable predator and consumer of vertebrate prey than the extant Mellivora, reaching the low end of the bite force estimates for the larger and more robust Eomellivora.

This article describes the first find of blind snake remains from the Middle Miocene sediments in the Vračević locality (Western Serbia). The numerous snake remains were isolated from the fossil material of the Vračević site. Among the many fragmented vertebrae, only one has been identified as belonging to a ‘scolecophidian’. This vertebra is characterized by the neural arches depressed dorsoventrally; the vestigial neural spine limited to the most posterior part of a neural arch; posterodorsal lamina of neural arch slightly concave; paradiapophyses developed above the ventral margin of cotylar rim; indistinct haemal keel visible only on the anterior part of vertebra centrum.

The studied crevasse-splay complex, situated within the 1st Mid-Polish lignite seam (MPLS-1), ranks amongst the best-developed and most readily accessible for direct research of all hard coal and lignite occurrences worldwide. The sandy-coaly sediments constituting it required a number of field and laboratory tests. However, the present article focuses solely on sedimentological and statistical analyses of sediments along a selected key section, the most important results of which are presented below. First of all, data obtained in previous sedimentological studies have been confirmed, in that individual segments of this complex represent both subaerial and subaqueous types of crevasse splays. On the one hand, their sediments are characterised by an extremely high content of coalified organic matter, reaching 20–40 wt.% in some samples; on the other, these crevasse splays are composed of fine sands with a median and mean grain size of 0.15 mm. In addition, the remaining statistical parameters (standard deviation, skewness and kurtosis) indicate a very good sorting of these sands, no significant so-called ‘tails’ and a better sorting close to the sediment mean grain size value, respectively.

• Describe Cinnamomum fossil using leaf epidermal anatomy for the first time. • Tropical, warm and humid climatic conditions suggested during the deposition. • Review the phytogeography and highlight the phytogeographic implication of Cinnamomum. Cinnamomum Schaeffer (avocado, family Lauraceae), commonly known as cinnamon tree, is a highly diverse, economically important evergreen element of tropical and subtropical regions of the world. In the present work, several compressed leaf remains similar to modern leaves of Cinnamomum are recovered from the lower part of the Siwalik strata (middle Miocene) of Darjeeling foothills, eastern Himalaya. The fossil specimens are characterized by an elliptic to ovate lamina, acute to short acuminate apex, round to acute base, basal as well as suprabasal acrodromous type of primary venation, and anomocytic type of stomata. Based on leaf architecture (macro- and micromorphological features) and using leaf epidermal anatomy, these Siwalik fossil leaves are confidently assigned to the genus Cinnamomum and are recognized as a new species: C. miocenicum Mahato, Hazra et Khan. The evidence of current Siwalik specimens and earlier-reported fossil species similar to thermophilic Cinnamomum in appreciable numbers from other Siwalik localities (Darjeeling, Uttarakhand, and Nepal) suggests that Cinnamomum was a common Siwalik element, pointing toward the existence of tropical, warm and humid climate conditions during the Siwalik sedimentation time. This conclusion is also supported by epifoliar fungal remains recovered from cuticular fragments of this lauraceous taxon. This finding also represents an essential source of data for understanding Cinnamomum 's evolution and deep time diversification. We review in detail the biogeographic history and suggest possible migratory routes of the genus from an Asian perspective. [ABSTRACT FROM AUTHOR]

During the Miocene, several reefs formed in the Beikang Basin, South China Sea, which may be potential targets for hydrocarbon exploration. This is due to the environment that developed as a result of the collision, splitting, and splicing of the Nansha Block, which was influenced by the Neogene expansion of the area. However, studies on the types, distribution, controlling factors, and evolution stages of these reefs are scarce. In this study, we used high-resolution seismic data and extensive well-drilling records to gain insights into the evolution of reefs in this particular area. Six distinct types of reefs, namely, the point reef, the platform-edge reef, the block reef, the bedded reef, the pinnacle reef, and the atoll reef, were identified based on our data. These reefs underwent four stages of development. During the initial stage, a few small-sized point reefs emerged in the basin and experienced significant growth during the early Middle Miocene. In the flourishing stage, the reefs predominantly thrived around the Central Uplift and Eastern Uplift areas. In the recession stage, the reefs began to deteriorate during the late Middle Miocene period as a result of the rapid increase in relative sea level caused by tectonic subsidence. In the submerged stage, since the Late Miocene, as the relative sea level continued to rise steadily over time, many reefs that had previously flourished surrounding the Central Uplift and Eastern Uplift areas became submerged underwater, with only a handful of atoll reefs surviving near islands located on the Eastern Uplift. This study indicated the presence of a significant number of well-preserved reefs in the Beikang Basin that have experienced minimal subsequent diagenesis and therefore exhibit high potential as reservoirs for oil and gas exploration. [ABSTRACT FROM AUTHOR]

Formed during marine regression periods, shelf valleys (SVs) are preterit river flows on the exposed continental shelf. This study investigates the influence of tectonic activity on forming these important morphological features. This research combines bathymetric, magnetometry, and seismic data to analyze the role of tectonic events in SV genesis and positioning. The bathymetric dataset provides information on SV locations and geometries along the continental shelf, whereas the 2D seismic sections illustrate that SVs formed above post-rift faults that reached Quaternary deposits. Aeromagnetic data indicates that the shallow and deep structures of the basement and sedimentary column-controlled SV locations and evolution. The multi-data integration demonstrates a strong correlation between neotectonic structures and SV location and geometries from the inner shelf (-25 m) to the shelf break (-55 m). The analysis of the 2D seismic data indicated that high-angle faults, formed under a strikeslip tectonic regime, primarily affected the Middle Miocene deposits beneath the shelf valleys. The formation of "negative flower pattern structures" was identified as a primary structural mechanism that contributed to SV formation. Reactivation events that occurred from the Late Cretaceous onwards, gave rise to these faults, which control SV formation and the capture of preterit drainage on the exposed continental shelf. The SV geometries display straight patterns and abrupt changes in direction (90°) due to the interplay of the NE-SW and NW-SE aligned faults. The results reinforce the importance of considering tectonic activity in the formation and evolution of shelf valleys. [ABSTRACT FROM AUTHOR]

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Leaf imprints of four fossil taxa from the Middle Miocene flora of Satovcha (SW Bulgaria) have been studied. The taxa Dalbergia aff. cochinchinensis, Lithocarpus aff. lucidus, Podocarpus aff. nubigenus, and Populus platyphylla are new for the Bulgarian fossil flora. [ABSTRACT FROM AUTHOR]

The article reviews of the Galliformes fo from the Mátraszőlős 3 site in Hungary from the Middle Miocene. A total of 200 bones have so far been recovered from site at Mátraszőlős 3, of which the identification of 95 bones will be discussed in this article, including anatomical differences between species. Within the fossil record, Palaeocryptonix hungaricus (Jánossy 1991) and three species of Palaeortyx have been identify (P. phasianoides Milne-Edwards, 1869, P. gallica Milne-Edwards, 1869 and P. brevipes Milne-Edwards, 1869). Only one bone of P. brevipes was recovered. As the appearance of the members of the family can be traced back to the early Oligocene, while the majority of the species are of Neogene origin, the study contributes to a better understanding of the distribution of extinct pheasant speciesin the Carpathian Basin. [ABSTRACT FROM AUTHOR]

In the 90-m river bank of the middle reaches of the Icha River, thick strata of volcano-sedimentary deposits represented by pyroclastic rocks and siliceous tuffites with layers of diatomites were studied. Representative diatom assemblages assigned to the Middle Miocene Denticulopsis hyalina Zone (14.9–13.1 Ma) indicate relatively deep-water conditions of the marine basin. Comparison with the data on diatom assemblages from reference sections of West Kamchatka indicates that the deposits of the Tyrkachyn section belong to the upper part of the Kakert Formation. The petrographic composition and lithological structure of volcanogenic formations (members 1, 2, and 4) suggest that they are the product of pyroclastic flows associated with volcanic activity in central Kamchatka. It is supposed that members 1 and 2 were formed in subaerial conditions, as indicated by the complete absence of marine microfossils, signs of primary volcanic stratification, and the absence of layering. The sediments of member 4 with eroded contacts and pronounced layering apparently accumulated in a subaqueous setting. [ABSTRACT FROM AUTHOR]

Sedimentary organic matter concentrated in source rocks forms the main source for the formation of hydrocarbons. Its deposition and preservation are strongly controlled by the depositional environment and paleoclimate. This study evaluates the paleoenvironment and the paleoclimatic controls of sediments in the Middle Miocene Balikpapan Group, Mahakam Delta of the Lower Kutai Basin, Indonesia. The sedimentary succession of the Mentawir Formation, encountered in three wells (MHK 1, MHK 3, and MHK 4), contains interbedded sandstones, siltstones, shales, and coal. Gamma ray log analysis has revealed four facies associations: (a) funnel-, (b) bell-, (c) cylindrical-, and (d) bow-shaped patterns, which, together with sedimentological and mineralogical analysis, suggest a fluvio-deltaic depositional environment during the Middle Miocene in the study area. Sedimentary successions from wells MHK 1 and MHK 3 comprise interbedded sandstone and siltstones and are interpreted to represent repeatedly occurring delta plain, delta front, and prodelta deposits. The succession encountered in well MHK 4 mostly consists of amalgamated sandstones and indicates a predominantly fluvial to upper delta plain environment with distributary channels and crevasse splays interbedded with only thin delta front deposits. X-ray diffraction–clay fraction analysis shows that the <2 μm clay-sized fraction consists of kaolinite (38%–67%), illite (14%–29%), chlorite (2%–17%), and mixed-layer illite/smectite (I/S) (14%–30%). Kaolinite formation and abundance indicates a hinterland climate classified as type Af (tropical rainforest) and intensive chemical weathering conditions in the source areas related to tropical to sub-tropical climates with high precipitation. Under such climatic conditions, kaolinite and I/S mixed-layer minerals are preferentially formed because the characteristic ions, K+, Na+, Ca2+, and Fe2+, are leached away. Thus, the production, transport, distribution, and preservation of sedimentary organic matter in the onshore Mentawir Formation of the Balikpapan Group are predominantly controlled by the humid tropical climate and fluvio-deltaic processes. [ABSTRACT FROM AUTHOR]

New data from the middle Miocene Satovcha paleoflora (SW Bulgaria) are presented. The three taxa studied here, which belong to the Division Pinophyta are defined on the basis of fossil disseminules. Cephalotaxus aff. fortunei was determined by an aril impression. Picea aff. shrenkiana and Pinus aff. mugo are identified by winged seed impressions. [ABSTRACT FROM AUTHOR]

A revision of small ducks (the size of the modern teal Anas crecca or smaller) from the middle Miocene of France (Sansan locality) and Mongolia (Sharga locality) clarified the taxonomic status and systematic position of the well-known species Anas velox Milne-Edwards, 1868 and Anas soporata Kurochkin, 1976. It is shown that three small members of the family Anatidae are present in the fauna of the Sansan locality: Anas velox is a diving duck, partly similar to modern Histrionicus, but smaller–here this species is transferred to the fossil genus Protomelanitta Zelenkov, 2011 (basal Mergini). A somewhat smaller taxon from Sansan belongs to the ecological group of dabbling ducks, and is identified as Anas soporata, a species that was previously described from Mongolia and here transferred to the genus Mioquerquedula Zelenkov et Kurochkin, 2012. In addition, yet another very small duck of unclear systematic position is present in the fauna of Sansan. New materials on Mioquerquedula soporata comb. nov. and M. minutissima Zelenkov et Kurochkin, 2012 are also described from the middle Miocene of Mongolia. [ABSTRACT FROM AUTHOR]

The current study of Jeribe Formation (Middle Miocene) at Zurbatiya area, South-East of Iraq. It is, structurally, located in the Low Folded Zone. The topic depends mainly on the study of microfacies under a microscope. One surface section in the Zurbatiya area is represented in the Wadi Al-Numur section. It is composed basically of dolomitic limestone. Petrography provides a diversity of fauna, such as benthic foraminifera Miliolid, Borelis melo curdica, and Rotalia in addition to Ostracoda, Algae, Coral, and Mollusks. Borelis melo curdica is considered an index fossil for the Jeribe Formation. The non-skeletal grains like peloids, ooids intraclasts, and extraclasts. The Jeribe Formation was affected by many diagenetic processes like neomorphisim, dissolution, cementation, dolomitization, compaction, and silicification. Sedimentary microfacies are classified into three main microfacies, which are dolomudstone, dolowackestone, and dolopackstone. These microfacies were divided into many submicrofacies, which are peloidal dolomudstone, ostracods dolomudstone, rotaliids dolowackstone, miliolid dolowackstone, bioclasts dolowackstone, green and red algae dolowackstone, red algae dolopackestone, and coral dolopackestone. The evidence from petrography and microfacies analysis supports that the Jeribe Formation was deposited in the back reef, reef, and lagoon environments. [ABSTRACT FROM AUTHOR]

In the 90-m river bank of the middle reaches of the Icha River, thick strata of volcano-sedimentary deposits represented by pyroclastic rocks and siliceous tuffites with layers of diatomites were studied. Representative diatom assemblages assigned to the Middle Miocene Denticulopsis hyalina Zone (14.9–13.1 Ma) indicate relatively deep-water conditions of the marine basin. Comparison with the data on diatom assemblages from reference sections of Western Kamchatka indicates that the deposits of the Tyrkachin section belong to the upper part of the Kakert Formation. The petrographic composition and lithological structure of volcanogenic formations (members 1, 2, and 4) suggest that they are the product of pyroclastic flows associated with volcanic activity in central Kamchatka. It is assumed that Members 1 and 2 were formed in subaerial conditions, as indicated by the complete absence of marine microfossils, signs of primary volcanic stratification, and the absence of layering. The sediments of Member 4 with eroded contacts and pronounced layering apparently accumulated in a subaqueous setting.

The elasmotheres were well diversified and widespread throughout the Neogene in Eurasia and East Africa. Here we report a new elasmothere genus and species, Tongxinotherium latirhinum gen. et sp. nov., from the Zhang'enbao Formation (middle Miocene) of Tongxin, Ningxia, China. The new genus is characterized by a broad and thick nasal bone, the 'U'-shaped nasal notch located at the level of P3, the anterior margin of the orbit situated at the level of M2, subhypsodont teeth covered and filled by plentiful cement, slightly developed enamel foldings, expanded protocone with anterior and posterior constrictions, the middle valley and posterior valley closed on the premolars, protoloph separated from the ectoloph on P2, and buccal and lingual cingula present on premolars, but absent on molars. A phylogenetic analysis reveals that Tongxinotherium latirhinum gen. et sp. nov. is more derived than the early elasmotheres, and more primitive than Iranotherium and Ningxiatherium, bridging a morphological and stratigraphical gap between them. The discovery of new material improves the morphological characteristics of the early elasmotheres' horns and increases the diversity of the middle Miocene elasmotheres. [ABSTRACT FROM AUTHOR]

Five out of the original nine syntypes of Astarte pulchella Baily, 1858 (junior synonym of Davidaschvilia (Zhgentiana) gentilis (Eichwald, 1851)) are discovered in the Natural History Museum, London. A lectotype is designated, described, and illustrated, paralectotypes are indicated, illustrated and a detailed synonymy of the species is provided. The importance of the species as characteristic of the Karaganian Regional Stage of the Eastern Paratethys, Middle Miocene (= Serravallian) is recognized. [ABSTRACT FROM AUTHOR]

Percrocuta xixiaensis sp. nov. from numerous localities in the Zhang'enbao Formation of Tongxin, Ningxia, China, is described here. Its fossils include the first complete cranium of Percrocuta and represent the best materials of this genus hitherto published. The bulla of P. xixiaensis suggests Percrocuta as true hyaenids rather than 'false hyenas (percrocutids)' which were believed to evolve independently from Stenoplesictis-like ancestors. The m1 of P. xixiaensis is more complex than Stenoplesictis and other Percrocuta species, indicating a relationship with other Miocene hyaenids. Cranial features like the small frontal sinus, the low neurocranium and the weak zygomatic process in P. xixiaensis are less adapted to bone cracking than its robust premolars. P. xixiaensis is close to P. miocenica but differs from the latter in narrower premolars and less reduced talonid of m1. It probably predates P. miocenica, which suggests an age of MN5 (early Middle Miocene) for the localities in the Zhang'enbao Formation of Tongxin. urn:lsid:zoobank.org:act:E3B79008-6443-478A-B7A2-BAAE44CC8B63 [ABSTRACT FROM AUTHOR]

During the Miocene, several reefs formed in the Beikang Basin, South China Sea, which may be potential targets for hydrocarbon exploration. This is due to the environment that developed as a result of the collision, splitting, and splicing of the Nansha Block, which was influenced by the Neogene expansion of the area. However, studies on the types, distribution, controlling factors, and evolution stages of these reefs are scarce. In this study, we used high-resolution seismic data and extensive well-drilling records to gain insights into the evolution of reefs in this particular area. Six distinct types of reefs, namely, the point reef, the platform-edge reef, the block reef, the bedded reef, the pinnacle reef, and the atoll reef, were identified based on our data. These reefs underwent four stages of development. During the initial stage, a few small-sized point reefs emerged in the basin and experienced significant growth during the early Middle Miocene. In the flourishing stage, the reefs predominantly thrived around the Central Uplift and Eastern Uplift areas. In the recession stage, the reefs began to deteriorate during the late Middle Miocene period as a result of the rapid increase in relative sea level caused by tectonic subsidence. In the submerged stage, since the Late Miocene, as the relative sea level continued to rise steadily over time, many reefs that had previously flourished surrounding the Central Uplift and Eastern Uplift areas became submerged underwater, with only a handful of atoll reefs surviving near islands located on the Eastern Uplift. This study indicated the presence of a significant number of well-preserved reefs in the Beikang Basin that have experienced minimal subsequent diagenesis and therefore exhibit high potential as reservoirs for oil and gas exploration.

Dental remains of the erinaceid Galerix rutlandae and a talpid attributed to the subfamily Uropsilinae are reported, the first members of these families from the Miocene Siwalik exposures of India. They come from deposits equivalent to the Chinji Formation at Ramnagar, northwestern India. Uropsilinae is recorded for the first time from the Indian subcontinent. This finding extends the spatial range of the subfamily and indicates that this immigrant reached the Indian subcontinent from the west, but could not survive past the Miocene. [ABSTRACT FROM AUTHOR]

Newly collected Early Badenian (Middle Miocene) Conorbidae and Conidae assemblages are presented from three localities in the Hungarian part of the Pannonian Basin. Ten species - among others Pseudonoduloconus wagneri (Boettger) - are recorded for the first time in the region, others show extended geographical distribution. A new species, Monteiroconus strauszi n. sp. is designated. With 67 figures and 1 table. [ABSTRACT FROM AUTHOR]

The five specimens of Miotragocerus gluten were collected from the Lower Siwalik outcrops nearby the villages Chabbar Sayadan and Phadial in Punjab, Pakistan. The newly discovered specimens include the two horn cores and isolated teeth. Miotragocerus gluten is the medium-sized bovids, having brachydont to the sub-hypsodont type of dentition. The cusps are elevated, and the crown is surrounded by a rugose enamel layer. The present study reveals the abundance of bovids in the middle Miocene deposits which indicates a grassland ecosystem in this area. [ABSTRACT FROM AUTHOR]

Five new ostracod species belonging to three genera from the Fat'ha Formation (Middle Miocene) in the Takia area, Darbandi Bazian anticline Sulaymaniyah, Northeastern Iraq. These species are Schneiderella takensis sp.nov., Schneiderella bazensis sp.nov., Sulcostocythere takensis sp.nov., Sulcostocythere bazeansis sp.nov., and Neomonoceratina takensis sp.nov. Those genera are showing affinities with ostracods of Mediterranean and Indopacific Bioprovinces. [ABSTRACT FROM AUTHOR]

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The Neogene of Kutch, India is well known for its rich marine and terrestrial vertebrate assemblages. However, the data of piscean fauna from the middle Miocene of India is very scarce. We report here additional chondrichthyan and osteichthyan remains from the middle Miocene deposit of Chhasra Formation, Palasava site, Kutch, Gujarat, India. The elasmobranchs include Carcharhinus Blainville, 1816 (C. brevipinna (Müller & Henle, 1839), C. falciformis (Müller & Henle, 1839), C. cf. leucas, C. aff. perezi, Carcharhinus sp.), Negaprion Whitley, 1940 (Negaprion sp.), Aetobatus Blainville, 1816 (Aetobatus sp.), Myliobatis Cuvier, 1816 (Myliobatis sp.), Dasyatis Rafinesque, 1810 (D. probsti Cappetta, 1970, D. rugosa Probst, 1877), Himantura Müller & Henle, 1837 (H. menoni Sahni & Mehrotra, 1981), Pastinachus Rüppell, 1829 (Pastinachus sp.), and Taeniurops Garman, 1913 (Taeniurops sp.). The teleosts of Palasava are represented by four families including Bagridae Bleeker, 1858, Channidae Fowler, 1934, Characidae Latreille, 1925 and Cyprinidae Cuvier, 1817. Sørensen-Dice coefficient data of Palasava elasmobranchs show a good similarity index with their counterparts in the Mediterranean Sea suggesting the existence of short-lived reopening of the marine pathway. However, a much higher faunal affinity with those of Eastern Pacific indicates a gradual shift in migration path through the Pacific Ocean to Indo-Pacific region after the permanent landbridge was formed. The vertebrate fauna from the Palasava suggests a coastal, marginal marine, near-shore littoral to neritic environment of deposition with the influence of freshwater riverine system. The integration of the floras and faunas from Palasava locality indicates the presence of warm, humid/ wet, tropical to sub-tropical environmental conditions during the middle Miocene. [ABSTRACT FROM AUTHOR]

Long‐term organic carbon (OC) burial on continental shelves has been widely recognized for regulating atmospheric CO2 (pCO2) and the global climate. However, quantitatively assessing shelf OC burial's role and process in prominent climate transitions is challenging. Using 367 drilling sites, we evaluated the impact of OC burial on the Sunda Shelf, the world's largest tropical shelf, on the middle Miocene carbon perturbation and climate change. Comparing the Miocene Climatic Optimum (MCO) and the Middle Miocene Climate Transition (MMCT) results demonstrated that OC was buried faster during the MMCT with an increment of 0.07–0.14 × 103 GtC/Myr. This would cause an additional 34.77–69.16 ppm pCO2 sequestration, contributing at least one‐sixth of the global pCO2 reduction. We found OC burial regulated the long‐standing Monterey carbon isotope excursion via negative and positive feedbacks during the MCO and MMCT, respectively. Expanded terrestrial carbon reservoirs and enhanced burial efficiency were key steps in the latter positive feedback. Plain Language Summary: The organic carbon (OC) formed by the photosynthesis of marine and terrestrial organisms consumes atmospheric CO2 (pCO2). Its long‐term burial in marine environments, especially on continental shelves, could influence the global carbon cycle and induce climate change. However, precisely assessing how much OC has been buried on shelves and quantifying how it affected climate change in the geological past is challenging. This is mainly due to the difficulty of obtaining complete spatial‐temporal records buried deeply on shelves and the complexity of climate feedbacks involving OC burial. To fill this gap to a certain extent, we calculated the middle Miocene OC burial of the Sunda Shelf, the world's largest tropical shelf, using 367 drilling sites and evaluated its impact on the profound carbon perturbation and climate transition of this period. We found that more OC was buried during the greenhouse period, but a faster burial rate occurred after polar cooling. The accelerated OC burial on the Sunda Shelf would cause an additional 34.77–69.16 ppm pCO2 sequestration, accounting for at least one‐sixth of the global pCO2 reduction of the middle Miocene. Efficient OC burial on the shelf was promoted by drainage system progradation and vegetation expansion arose along with sea level drop. Key Points: Organic carbon (OC) burial on the Sunda Shelf is essential to the global carbon cycle during the middle MioceneThe OC burial rate of the Middle Miocene Climate Transition (MMCT) was faster than that of the Miocene Climatic OptimumExpanded terrestrial carbon reservoirs and enhanced organic matter burial efficiency promoted the MMCT [ABSTRACT FROM AUTHOR]

The South Asian summer monsoon (SASM) remarkably strengthened during the Middle Miocene (16–11 Ma), coincident with the rapid uplifts of the Iranian Plateau (IP) and the Himalaya (HM). Although the development of the SASM has long been linked to the topographic changes in the Tibetan Plateau (TP) region, the effects of the HM and IP uplift are still vigorously debated, and the underlying mechanisms remain unclear. Based on Middle Miocene paleogeography, we employ the fully coupled earth system model CESM to perform a set of topographic sensitivity experiments with altered altitudes of the IP and the HM. Our simulations reproduce the strengthening of the SASM in northwestern India and over the Arabian Sea, largely attributing to the thermal effect of the IP uplift. The elevated IP insulates the warm and moist airs from the westerlies in the south of the IP and produces a low-level cyclonic circulation around the IP, which leads to the convergence of the warm and moist air in the northwestern India and triggers positive feedback between the moist convection and the large-scale monsoon circulation, further enhancing the monsoonal precipitation. Whereas the HM uplift produces orographic precipitation without favorable circulation adjustment for the SASM. We thus interpret the intensification of the Middle Miocene SASM in the western part of the South Asia as a response to the IP uplift while the subtle SASM change in eastern India reflects the effects of the HM uplift. [ABSTRACT FROM AUTHOR]

The results of study of the Middle Miocene Il'inskii Regional Stage of Western Kamchatka and its typical mollusks are presented. Its age analogs are identified in Japan, on Sakhalin, and in the Koryak Upland. The features of the distribution of mollusk assemblages of the beginning of the Middle Miocene are revealed at various latitudes of shelf zones of Northwestern Pacific. It is suggested that the warm (subtropical and low boreal) mollusk assemblages migrated at the beginning of the Middle Miocene from the latitudes of Japan to Northern Kamchatka. This event was probably related to the global Miocene warming, which led to certain changes in the oceanic hydroregime, in particular, to the movement of relatively warm water masses to the north. In the North Pacific, this event followed the tectonic reconstructions, which affected the evolution of marine transgression reflected in the formation of sedimentary complexes of many regions of the world. [ABSTRACT FROM AUTHOR]

The Middle Miocene (15.99–11.65 Ma) of Europe witnessed major climatic, environmental, and vegetational change, yet we are lacking detailed reconstructions of Middle Miocene temperature and precipitation patterns over Europe. Here, we use a high‐resolution (∼0.75°) isotope‐enabled general circulation model (ECHAM5‐wiso) with time‐specific boundary conditions to investigate changes in temperature, precipitation, and δ18O in precipitation (δ18Op). Experiments were designed with variable elevation configurations of the European Alps and different atmospheric CO2 levels to examine the influence of Alpine elevation and global climate forcing on regional climate and δ18Op patterns. Modeling results are in agreement with available paleobotanical temperature data and with low‐resolution Middle Miocene experiments of the Miocene Model Intercomparison Project (MioMIP1). However, simulated precipitation rates are 300–500 mm/yr lower in the Middle Miocene than for pre‐industrial times for central Europe. This result is consistent with precipitation estimates from herpetological fossil assemblages, but contradicts precipitation estimates from paleobotanical data. We attribute the Middle Miocene precipitation change in Europe to shifts in large‐scale pressure patterns in the North Atlantic and over Europe and associated changes in wind direction and humidity. We suggest that global climate forcing contributed to a maximum δ18Op change of ∼2‰ over high elevation (Alps) and ∼1‰ over low elevation regions. In contrast, we observe a maximum modeled δ18Op decrease of 8‰ across the Alpine orogen due to Alpine topography. However, the elevation‐δ18Op lapse rate shallows in the Middle Miocene, leading to a possible underestimation of paleotopography when using present‐day δ18Op—elevation relationships data for stable isotope paleoaltimetry studies. Key Points: A high‐resolution isotope‐enabled general circulation model is used to explore Middle Miocene climate and precipitation δ18O across EuropeMiddle Miocene bi‐directional precipitation change consistent with herpetological fossils and account for precipitation δ18O variationsGlobal Miocene climate forcing contributed a max δ18O change of ∼2‰ over the high Alpine elevation and to ∼1‰ over low elevation [ABSTRACT FROM AUTHOR]

Abstract The Miocene aquatic and terrestrial fossil record from western Amazonia constitute a clear evidence of the palaeoenvironmental diversity that prevailed in the area, prior to the establishment of the Amazon River drainage. During the Miocene, the region was characterized by a freshwater megawetland basin, influenced by episodic shallow-marine incursions. A fossil vertebrate collection from the middle Miocene strata of the Pebas Formation is here studied and described. This historical collection was recovered in 1912 along the banks of the Itaya River (Iquitos, Peru), during a scientific expedition led by two scientists of the University of Zurich, Hans Bluntschli and Bernhard Peyer. Our findings include a total of 34 taxa, including stingrays, bony fishes, turtles, snakes, crocodylians, and lizards. Fishes are the most abundant group in the assemblage (~ 23 taxa), including the first fossil record of the freshwater serrasalmids Serrasalmus, and Mylossoma, and the hemiodontid Hemiodus for the Pebas system, with the latter representing the first fossil be discovered for the entire Hemiodontidae. The presence of a representative of Colubroidea in the middle Miocene of Iquitos supports the hypothesis of arrival and dispersal of these snakes into South America earlier than previously expected. This fossil assemblage sheds light on the palaeoenvironments, and the geographical/temporal range of several aquatic/terrestrial lineages inhabiting the Amazonian region.

Determining whether the high-latitude Bering land bridge (BLB) was ecologically suitable for the migration of mesothermal plants is significant for Holarctic phytogeographic inferences. Paleobotanical studies provide a critical source of data on the latitudinal positions of different plant lineages at different times, permitting assessment of the efficacy of the BLB for migration. Here we report exceptionally preserved fossils of Firmiana and Tilia endochrysea from the middle Miocene of South Korea. This represents a new reliable record of Firmiana and the first discovery of the T. endochrysea lineage in the fossil record of Asia. The occurrence of these fossils in South Korea indicates that the two lineages had a distribution that extended much farther north during the middle Miocene, but they were still geographically remote from the BLB. In light of the broader fossil record of Asia, our study shows that, in the middle Miocene, some mesothermal plants apparently inhabited the territory adjacent to the BLB and thus they were possibly capable of utilizing the BLB as a migratory corridor. Some other mesothermal plants, such as Firmiana and the T. endochrysea lineages, however, are restricted to more southern regions relative to the BLB based on current fossil evidence. These lineages may have been ecologically unable to traverse the BLB, which raises questions about the efficacy of the BLB as a universal exchange route for mesothermal plants between Asia and North America during the middle Miocene.

Using light and scanning electron microscopy, a new species Aulacoseira capitalina Titova et Usoltseva from the Middle Miocene deposits of the Barguzin Valley is described. It is shown that the new species is similar to other elliptical species in terms of elliptical valve face profile, diameter, deep ringleist, but differs in the shape of separating spines, the absence of ridge structure and the shape of rimoportulae. The finding of A. capitalina in the Middle Miocene deposits of the Barguzin Valley expands the range of distribution of elliptical species.

The Middle Miocene Balikpapan Formation is exposed in the Samarinda Anticlinorium, which forms part of the Lower Kutai Basin situated on East Kalimantan, Indonesia. The Balikpapan Formation is considered the main source rock for oil and gas fields in Lower Kutai Basin. This study integrates sedimentology, organic geochemistry, organic petrography and calcareous nannofossil analysis to characterize the depositional environment, to determine the source of the organic matter, and to assess the hydrocarbon potential of the Balikpapan Formation. The studied sections contain at one locality calcareous nannofossil assemblages with low diversity including Sphenolithus heteromorphus , suggesting nannofossil zones NN4 – NN5 (upper Burdigalian - Langhian-lower Serravallian) are restricted to the Air Putih section in the northeastern part of the study area. Six facies associations were identified in the study area, comprising eleven lithofacies, interpreted as fluvial-deltaic to shallow marine in origin. The fine-grained lithofacies include shale, coaly shale and coal while the coarse-grained facies include sandstone and sandy conglomerates. The geochemical results (TOC) indicate that the analyzed samples have strongly varying total organic carbon (TOC) contents. The organic matter is composed of type III (gas-prone) and type II-III (mixed oil and gas prone) kerogen, with HI values ranging from 32 to 252 mg HC/g TOC. The Rock-Eval parameter T max 409–441 °C and vitrinite reflectance values (0.40–0.67 %Rr) indicate that the sediments are immature to marginal mature. The rank of coal in the Balikpapan Formation ranges from the sub-bituminous to the high-volatile bituminous B stage. • Fluvio-deltaic to shallow marine depositional environment during the Middle Miocene. • Sphenolithus heteromorphus yielded upper Burdigalian-lower Serravallian age. • Coal formed on delta plain in ombrotrophic and marine influenced eutrophic mires. • Thermal maturity stage of the organic matter ranges from immature to early mature. [ABSTRACT FROM AUTHOR]