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The Mamonia Mélange in the Ayia Varvara area (southwestern Cyprus) is characterized by a matrix supported mélange which is composed of tectonized siltstones and mudstones with numerous blocks that were derived from the Mamonia Allochthonous Complex (Petra tou Romiou Formation reefal limestones, Phasoula Formation volcanics, Kholetria Member pelagic limestones, Akamas Member sandstone, Parekklisha Member sandstone, Ayia Varvara Formation metamorphics and Episkopi Formation radiolarian cherts). Subordinate blocks were derived from the Troodos Ophiolite Complex: serpentinites, gabbro, pillow lavas and cherty umbers (Perapedhi Formation). Radiolarian assemblages from chert blocks display a broad spectrum in age, ranging from the Late Triassic (latest Carnian–early Norian) to the youngest Cenomanian. The composition of the mélange in the Ayia Varvara area differs from the one described in the Petra tou Romiou area (SW Cyprus), as various lithologies were recorded (like Akamas Member sandstone and Parekklisha Member sandstone) which were not detected previously. The Mamonia Mélange was formed during the Late Cretaceous, most probably after the end of deposition of the Perapedhi Formation (late Santonian–early Campanian). [ABSTRACT FROM AUTHOR]

The study of new finds of mosasaurids from the Izhberda locality (Southern Urals, Orenburg Region) has made it possible to record for the first time the presence of mosasaurs from the subfamilies Mosasaurinae, Tylosaurinae, and Plioplatecarpinae from the Upper Cretaceous of the Orenburg Region, including representatives of the genera Mosasaurus, Prognathodon, and Clidastes, which are known from the Upper Cretaceous of North America and Western Europe. Of interest is the discovery of the tylosaurine Taniwhasaurus, previously known from New Zealand, Antarctica, South Africa, and Japan. Therefore, the Campanian mosasaurid fauna of the Southern Urals is intermediate and includes North American–European and Asia–Pacific taxa. However, all the finds of mosasaurs from the Izhberda locality can only be identified in open nomenclature, which makes detailed comparisons of the faunas difficult. Revision of the type series of mosasaur Liodon rhipaeus Bogolyubov, 1910 from the Southern Urals has allowed us to conclude that, in addition to the three mosasaurian vertebrae, it includes the ischium and posterior fragment of the mandible of a plesiosaur. Liodon rhipaeus is clearly a nomen dubium and the vertebrae of its type series cannot be identified more precisely than Tylosaurinae indet. [ABSTRACT FROM AUTHOR]

Numerous representatives of the genus Foremanina Empson-Morin, 1981, emend. nov. were studied from the Upper Cretaceous (Maastrichtian) of the Lefkara Formation (Cyprus). The diagnosis of the genus Foremanina is emended. The new species F. macropora sp. nov., F. coronata sp. nov. and F. ornata sp. nov. are described. F. macropora sp. nov. is recorded for the first time in the Campanian of Sakhalin. The paleogeographic distribution of genus Foremanina is expanded to include the Tethyan Realm and Pacific Realm including the Mid-Pacific Mountains and Hokkaido–Sakhalin paleobasin. The latest representatives of Foremanina were found for the first time in the upper Maastrichtian of Cyprus. The stratigraphic range of the genus Foremanina is expanded. [ABSTRACT FROM AUTHOR]

Microfaunal analysis of Cretaceous and Paleogene sediments collected over several decades from Western Siberia has illuminated the diversity, stratigraphic distribution, and paleoecological signifi cance of the rare low trochospiral benthic foraminiferal genus Bagginoides. Here, we describe two new species B. yamalensis n.sp. and B. tibeisalinella n.sp [ABSTRACT FROM AUTHOR]

Tyrannosaurids were the most derived group of Tyrannosauroidea and are characterized by having two body plans: gracile, long-snouted and robust, deep-snouted skulls. Both groups lived sympatrically in central Asia. Here, we report a new deep-snouted tyrannosaurid, Asiatyrannus xui gen. et sp. nov., from the Upper Cretaceous of Ganzhou City, southeastern China, which has produced the large-bodied and long-snouted Qianzhousaurus. Based on histological analysis, the holotype of Asiatyrannus xui is not a somatically mature adult, but it already passed through the most rapid growth stages. Asiatyrannus is a small to medium-sized tyrannosaurine, with a skull length of 47.5 cm and an estimated total body length of 3.5–4 m; or around half the size of Qianzhousaurus and other large-bodied tyrannosaurines in similar growth stages. Asiatyrannus and Qianzhousaurus are sympatric tyrannosaurid genera in the Maastrichtian of southeastern China. Asiatyrannus differs from Qianzhousaurus in that it has a proportionally deeper snout, longer premaxilla, deeper maxilla, and deeper dentary, and the cornual process of the lacrimal is inflated without developing a discrete horn. The different skull proportions and body sizes suggest that Asiatyrannus and Qianzhousaurus likely had different feeding strategies and occupied different ecological niches. [ABSTRACT FROM AUTHOR]

Atlantoceratodus iheringi (Ameghino, 1898) from Argentine territory is restudied based on its known tooth plates and newly discovered material, which includes previously unknown skull roof bones and vomerine tooth plates. The latter represent the first records of such elements from the Mesozoic era in South America. The comparative morphological analysis reveals its distinctiveness from other dipnoans, and offers valuable data for future systematic and phylogenetic research. The pterygopalatine tooth plates display narrow-based first denticulations and lack anterior wear facets, with the inner angle positioned at the level of the second denticulation. Similarly, the prearticular tooth plates feature straight mediolingual edges, and a wide-based first denticulation without sinuosities at the tip. Histological sections are performed and analyzed in detail for the first time. A. iheringi presents in this aspect distinctive features such as: large-lumen denteons tending to cluster together, circumdenteonal dentine arranged in a double band (an inner birefringent and an outer monorefringent), and a disordered interdenteonal dentine, with birefringence surrounding denteons and areas with monorefringence. A. iheringi exhibits histological structure closer to Mesozoic and Cenozoic dipnoans than Paleozoic, especially resembling the disposition observed in the Upper Cretaceous Patagonian species Metaceratodus baibianorum. The wide distribution of features designated as diagnostic for Atlantoceratodus is discussed. [ABSTRACT FROM AUTHOR]

A new genus and species, Cretopleciofungivora simpsoni gen. et sp. nov., from the extinct family Pleciofungivoridae (Diptera: Bibionomorpha), is discovered in mid‐Cretaceous Kachin amber. Previously, this family was known only from imprints in sedimentary rocks of the Jurassic and the Lower Cretaceous. Discovery of a representative of Pleciofungivoridae in Kachin amber confirms the presence of the family in the Upper Cretaceous. The new species has a unique structure of fore tarsus, with lobed and extended tarsal segments II to IV, a feature hitherto known only in a few species of extant Sciaroidea. Although not particularly rare, the new species is currently known only from female specimens. Possible reasons for this phenomenon, very unusual in Sciaroidea, are briefly discussed, including parthenogenesis as a potentially plausible hypothesis. [ABSTRACT FROM AUTHOR]

A Cenomanian ammonite, Calycoceras (Calycoceras) naviculare (Mantell, 1822) (Acanthoceratidae, Ammonoidea) has been found in the well-known section of the Selbukhra Mountain in the vicinity of the village of Nauchnyi in southwestern Crimea. This is the first find of the ammonite in the upper Cenomanian deposits in the Crimea and in Russia. [ABSTRACT FROM AUTHOR]

Ammonites of the subfamily Collignoniceratinae have been found in the Turonian Stage of Western Siberia. These findings have made it possible to substantiate the Collignoniceras woollgari zone in the Middle Turonian of this region, to recognize the ammonite dispersal features in the Arctic region, and to clarify the paleogeography of the Turonian age. Based on the occurrence frequency of Collignoniceras woollgari regulare in the boreholes in the north of Western Siberia, their penetration into the West Siberian basin through the Arctic region from the Western Interior Sea of North America is most likely. Collignoniceratinae has been identified for the first time in the Upper Turonian of the Yangoda River (west of the Yenisei–Khatanga regional trough). [ABSTRACT FROM AUTHOR]

The Western Desert of Egypt is recognized for its significant potential in oil and gas reserves, making it a prominent hydrocarbon-producing area with conventional reservoirs. Recent findings from various wells suggest that unconventional reservoirs in the Western Desert may hold considerable promise. The primary objective of this study was to explore this potential. Accordingly, a comprehensive and multidisciplinary approach has been employed to assess the Abu Roash/F (AR/F) reservoir. The methodology involved meticulously examining formation characteristics and integrating borehole images with existing core data and thin sections. This integration aimed to analyse and interpret the lithofacies of the reservoir, with a specific focus on identifying fractures and decoding potential diagenesis effects. As a result, we successfully identified wells exhibiting optimal reservoir quality, unveiling the presence of fractured dolomite or vuggy dolomite in wells containing promising oil and gas pay intervals. Notably, some wells displayed low porosity (3%), yet seismic attribute maps in their vicinity indicated a high density of fractures. This underscores the importance of combining borehole images with seismic attributes to evaluate carbonate formations effectively. The fractures, predominantly oriented NW–SE, were found to be associated with deformation zones. Our findings emphasize the critical role of this integrated approach in unlocking the full potential of hydrocarbon reservoirs in the Western Desert. [ABSTRACT FROM AUTHOR]

Stratigraphy of Campanian deposits in the stratotype of the Kudrinskaya Formation in the Southwestern Crimea is revised. For the first time, integrated sedimentological, biostratigraphic (ichnofossils, cephalopods, inoceramids, foraminifers, dinocysts, nannoplankton, gilianelles), isotope-geochemical, paleo- and petromagnetic characteristics of the section were obtained. The boundary of the lower and upper Campanian is substantiated and confirmed by U–Pb dating of zircons from the well-known bentonite (kil) clay bed in the interval of 77–80 Ma. It is proposed to accept the Campanian Substage boundary of the General Stratigraphic Chart (for bipartite stage subdivision) at the top of the Chron C33r, located near the δ13C isotopic excursion "MCaE" – Mid-Campanian Event, near the first occurrence of the benthic foraminifer Brotzenella monterelensis and a number of other traditional biomarkers. [ABSTRACT FROM AUTHOR]

A Turonian ammonite, Kamerunoceras sp. ex gr. turoniense (d'Orb.) has been found for the first time in the southwestern Crimea, in the section of the Aksu-Dere ravine, northward of the village of Kudrino (Kacha River basin). This is the first discovery of representatives of this genus in Russia. [ABSTRACT FROM AUTHOR]

Abstract—In 394 samples characterizing 266 stratigraphic levels in four Turonian–Santonian sections of the Southwestern Crimea, characteristic remanent magnetization components (ChRM) acquired at the stage of diagenesis are identified. The obtained data fix the record of the paleosecular geomagnetic variation of high amplitude (root mean square deviation S = 25.9° with a fixed cut-off angle of 45°, which is about twice as high as the model S for this latitude) in the sediments formed during ~5–6 Myr and is interpreted as anomalous behavior of the geomagnetic field in the Turonian, Coniacian, and Santonian. [ABSTRACT FROM AUTHOR]

Numerous representatives of the genus Pseudodictyomitra Pessagno, 1977 were studied from the Upper Cretaceous of the Perapedhi Formation (Cyprus). The new species P. venusta sp. nov. is described. The description and stratigraphic range of P. crassa Bragina, 2013 are emended. [ABSTRACT FROM AUTHOR]

The stratigraphy of the Kerch–Taman region has been refined based on foraminiferal assemblages from the clay pulp of the Semigorsky, Andrusov, and Borukh-Oba mud volcanoes. Comparison with the fauna from the reference section of the Paleogene along the Belaya River (Republic of Adygea) enabled us to reveal deposits of the Middle Eocene (Cherkessk and Kuma formations of the Lutetian and Bartonian stages); Lower Oligocene (Pshekha Formation, Rupelian Stage), confirmed by finds of remains of pteropods; and Middle Miocene (Konkian and Sarmatian stages of the Eastern Paratethys regional scale of the Miocene). Cretaceous deposits (Semigorsky Volcano) are attributed to the Late Campanian–Maastrichtian. [ABSTRACT FROM AUTHOR]

Copyright of Sultan Qaboos University Journal for Science is the property of Sultan Qaboos University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abiostratigraphic assessment of the benthic foraminiferal record at International Ocean Discovery Program (IODP) Site U1513 in the Mentelle Basin (southeast Indian Ocean, offshore western Australia), yielding a Turonian through Santonian deep-water benthic foraminiferal assemblage is presented. Predominantly calcareous deep-water benthic foraminifera are recovered, whereas agglutinated benthic taxa show a rare occurrence. Epifaunal benthic foraminifera make up ~50% of the total assemblage during the Turonian to Santonian. The most frequently recorded taxa are gavelinellids and gyroidinoids. Adistal, bathyal depositional environment is inferred. Two distinct benthic foraminiferal associations, the Gavelinella berthelini association and the Notoplanulina rakauroana association, were identified in the 160 m-thick succession, and together they yield over 190 taxa. At Site U1513 the occurrence of important benthic foraminiferal markers such as Gavelinella berthelini and the Notoplanulina lineage allows a good correlation with other localities in the southern hemisphere and tentatively with the Pacific Realm. Gavelinella bethelini, which is present from the base of the Turonian succession, shows its last occurrence shortly after the Turonian/Coniacian boundary. Notoplanulina rakauroana is recorded to range from the lower Coniacian through the uppermost Santonian. Throughout the Southern Hemisphere, a similar sequence of benthic foraminiferal bioevents in the Upper Cretaceous can be identified at the Walvis Ridge, in South Africa, Argentina, Southern India, the Kerguelen Plateau, the Great Australian Bight, and in New Zealand. This study aims at contributing to the development of an Upper Cretaceous calcareous benthic foraminiferal zonation applicable to the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

The purpose of the research was to examine the Upper Cretaceous sedimentary sequence in northwest Iran, in particular, the Shahin Dezh geographical region in two stratigraphic sections, Godollu and Tark-e Viran, which revealed a thickness of 156 meters for the former and 114.5 meters for the latter. Field studies revealed that the lithological features and macroscopic characteristics of the rock sequence of the Godollu section can be divided into 12 lithological units. Sandstone petrofacies exhibit mature textural features and are classified as litharenites based on the composition of the main grains, reflecting sedimentation on a shallow marine shelf and slope. These studies also indicated that the carbonate sequence of the Tark-e Viran section can be divided into 11 separate lithological classes, and based on the laboratory studies, the microscopic samples consisted of three groups, namely, pelagic microfacies with mudstone bioclastic facies, Globotruncana wackestone, and Oligostegina packstone. These classifications are comparable to Flugel's SMF 3 and were deposited in the facies zone of FZ_1 and FZ_3, evoking the depositional environment of relatively deep seas. Geochemical studies on the elements of strontium, sodium, manganese, and iron revealed that the amount of strontium and sodium is very low while the amount of manganese and iron is higher than the carbonate equivalents of the present era. Due to the increased effect of late meteoric diagenesis, the amount of iron increases with the increase of manganese, and the changes of Sr/Ca compared to manganese represent an open diagenetic system reflecting that of the late meteoric diagenesis. As such, the studied limestones can be best classified as semi-polar types with the primary composition of calcite mineralogy. [ABSTRACT FROM AUTHOR]

Crocodyliformes have a well-known worldwilde fossil record, revealing a high diversity of morphological traits, habits and being abundant in their paleofaunas. Such abundance in the fossil record is remarkable in the tetrapod fossil record in the continental sequences of Bauru Group (Brazil), in the Cretaceous of the South America. Here we describe and analyse three specimens from Bauru Group, assigned to a poorly understood crocodyliform clade: Itasuchidae. Their morphological similarity assigned them as Pepesuchus (from Turonian / Coniacian of Araçatuba Formation), Itasuchus cf. jesuinoi, and cf. Roxochampsa paulistanus (both last from Campanian to Early Maastrichtian of Presidente Prudente Formation). The phylogenetic and morphometric results corroborated the monophyly of the Itasuchidae with some variation in its content regard to prior and similar analyses (i.e. inclusion of Stolokrosuchus, Barreirosuchus and Antaeusuchus; exclusion of Caririsuchus), also pointing out to the South American itasuchid species as occupying a crocodyliform morphospace, which can imply distinct niche occupations. The Bauru Group undergoes a diversity peak of archosaurs in Upper Cretaceous, with a remarkable Crocodyliformes radiation, such as the Itasuchidae group, which probably have their most early-diverging lineages rising from Lower Cretaceous of Africa. [ABSTRACT FROM AUTHOR]

The lithological, paleontological and biostratigraphic characteristics of the Turonian–Coniacian deposits of the Lower Bannovka section, the stratotype of the Bannovka Formation (Volga region, Turonian) are presented. Magnetostratigraphic characteristics of thе sediments have been supplemented and elaborated. Petromagnetic data contribute to more refined stratigraphy of the section and facilitate the revealing of depositional rhythmicity. Paleomagnetic data combined with benthic foraminifera data enable the most detailed correlation of the Turonian–Coniacian deposits in the Volga region. Results of a comprehensive study of this stratigraphic unit within the southeastern arch of the Ulyanovsk-Saratov trough revealed patterns in the distribution of the Gubkino Horizon, determined by regional tectonics and processes preceding deposition in the Coniacian and Santonian. [ABSTRACT FROM AUTHOR]

The carbonate of Khasib Formation in East Baghdad Oilfield, Central Iraq was geochemically investigated to interpret paleoredox conditions and source of rare earth elements (REEs) based on major, trace, and REEs geochemistry. SiO2 and Al2O3 concentrations are nearly the same in both wells, while CaO content just hardly differs between the EB10 and EB81 cores. The EB10 Well has higher concentrations of Th, Y, and Zr than the EB81 Well. However, both the ∑REE of EB10 (1.969-35.35, n=23) and EB81 (9.59-24.88, n=20) wells have low total REE content. These results show that the Khasib Formation's carbonate sedimentation contains seawater-like marine carbonate and PAAS-normalized REE + Y patterns accompanied by 1- light REE depletion (NdN/YbN= 0.40–0.95, n=23, and 0.54–0.90, n=20, respectively), 2- both positive to negative Ce anomalies (Ce/Ce*= 0.28-1.07, n=23; 0.39-1.76, n=20, respectively), as well as the 3- superchondritic Y/Ho ratio (23.25-57.5, n=23; 18.0-53.0, n=20, respectively). The terrigenous contribution, paleoredox conditions, and scavenging mechanisms were responsible for the observed variations in Ce components and Ce anomalies in the investigated cores. The rising U contents in the limestones (1.62-4.72 ppm) and authigenic U (0.66-4.44 ppm) indicate that dysoxic conditions were present when they were deposited. Further evidence from geochemical data suggests that diagenetic processes may be responsible for the positive Eu anomalies found in limestones. This implies that the Khasib Formation limestones may have kept their original seawater-like REE patterns. Due to trace amounts of detrital materials in certain specimens, there is identified variability in the REE + Y pattern and REE content. The current study shows that the limestones still display their original seawater-like patterns as long as shale contamination was minimal, and they act as a proxy for seawater. [ABSTRACT FROM AUTHOR]

New data on the taxonomic composition and stratigraphic distribution of benthic and planktonic foraminifera in the Campanian–Maastrichtian interval of the Beshkosh section (Southwestern Crimea) are presented. Samples were collected using the "sample-to-sample" method for different types of analysis. Zones and Beds were established on the basis the foraminiferal succession. The Angulogavelinella gracilis LC 18 Zone, Bolivinoides draco LC 21 Zone, Brotzenella praeacuta LC 22 Zone and Beds with Gavelinella sahlstroemi were recognized using benthic foraminifera and Beds with Laeviheterohelix glabrans, Guembelitria cretacea Zone were recognized using planktonic foraminifera. All recognized biostrata are correlated with magnetostratigraphic, palynomorph and macrofauna events. Beds and zones recognized based on benthic foraminifera are correlated with Campanian–Maastrichtian bioevents in sections of the European paleobiogeographic region. Planktonic foraminiferal data are correlated with the International Stratigraphic Scale (Tethys Region) and the regional stratigraphic scheme of Poland. For the first time, 15 species of nine planktonic foraminifera genera and 38 species (25 of which were found for the first time) of 25 benthic foraminifera genera have been identified in the Beshkosh section. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous strata of the Zagros area is named Gurpi Formation. The selected stratigraphic section is attributed to a part of Folded–Thrust belt Zone of the Zagros, located 90 km southeast of Shiraz (SW of Iran) and is affected by the Sarvestan basement Fault within the Interior Fars region. The Gurpi Formation is extended approximately 28 m thick and is mainly formed of marly limestone, shale and argillaceous limestone, The biostratigraphy of the Gurpi Formation was investigated by collecting 121 samples from a selected stratigraphic section. Microscopic investigation represents the presence of 12 genera and 27 species of planktonic foraminifera. The stratigraphic distribution of investigated planktonic foraminifera represents eight biozones. The identified biozones in the Kharameh area from base to the top of Gurpi Formation consist of Helvetoglobotruncana helvetica Total Range Zone, Marginotruncana sigali Partial Range Zone, Dicarinella primitiva Interval Zone, Dicarinella concavata Interval Zone, Dicarinella asymetrica Total Range Zone, Globotruncanita elevata Partial Range Zone, Globotruncana ventricosa Interval Zone, Globotruncana aegyptiaca Total Range Zone. Based on the identified planktonic foraminifera and the described biozones, the age of the Gurpi Formation is assigned from middle Turonian to early Maastrichtian. [ABSTRACT FROM AUTHOR]

The present study interprets the carbonate stacking patterns and their depositional controls in the Upper Cretaceous strata of the Ras Budran Field in the Gulf of Suez, Egypt, on the basis of integrated well logging and a geological report provided. A set of well logs was run for two wells (RB-A2 and RB-B2), comprising gamma ray, resistivity, density, neutron, sonic, and photoelectric factor. Composite logs and geological reports were also used to help deduce the lithological and biological description of the stratigraphic units under investigation. The stacking patterns of the carbonate rocks yielded three types of electro-facies. The first facies covers the lower part of the Brown Limestone (early Campanian) and reflects a cylindrical (aggrading) stacking pattern. This facies indicates keep-up carbonate deposition in a heterogeneous facies accumulated in shallow water. The second facies covers the upper part of the Brown Limestone (late Campanian) and displays a funnel (prograding) stacking pattern. This facies indicates the depositional setting of a shallow shoreline. The third facies covers the Sudr Chalk (Maastrichtian), for which a serrated stacking pattern indicates an aggradational environment. This pattern indicates a marine depositional setting both distal and deep. Therefore, the formation and evolution of the cyclical stacking pattern of the carbonate rocks reflects variations in accommodation potential that determines the environmental changes. The evolution of these deposits is mainly attributed to a combination of eustatic sea-level fluctuations and tectonic episodes within the basin. [ABSTRACT FROM AUTHOR]

The ichnological study of the Djebel Bouarif Cenomanian deposits (Northern Aurès Range, Algeria) revealed relatively abundant and diverse sclerobiont communities that are preserved in corals, bivalves and gastropods. Fossil traces are dominated by exceptionally preserved Gastrochaenolites, often with tracemakers (bivalves), which are preserved in situ, Entobia, and Maeandropolydora. Other borings are rare and are represented by a single specimen of Rogerella, Nihilichnus, and Spirolites. Among sclerozoans, encrusting juvenile oysters and non-oyster bivalves (Pseudolimea? granulata) are the most abundant groups. Other epibionts, such as gastropods and polychaetes (Glomerula serpentina), are less common; dwarf gastropods were located on a single oyster Costagyra olisiponensis, whereas Glomerula specimens were clustered on the lower and upper surfaces of coral Aspidiscus cristatus. Gastrochaenolites with original tracemakers and all the epibionts studied herein have not been described from the Djebel Bouarif Cenomanian deposits to date. The rare occurrences of Spirolites and Nihilichnus are reported from Algeria for the first time. [ABSTRACT FROM AUTHOR]

Marine mudstone of Coniacian age (c. 89.51-86.49 Ma) was deposited on a storm-dominated ramp spanning the foredeep of the Cretaceous Western Canada Foreland Basin. Marine flooding surfaces define 18 allomembers that thin over 300 km, from c. 140 m in the proximal foredeep to c. 20 m close to the forebulge crest. The broadly conformable succession of allomembers is partitioned into five 'tectono-stratigraphic units' by low-angle unconformities that bevel off c. 10 to 20 m of strata over 'arches' that have a length scale of c. 50-100 km and are bounded by relatively linear zones of flexure. Depositional history involved two alternate modes: 'Background' deposition of subtly-tapered allomembers took place on a planar sea floor, subject to regional flexural subsidence, with sea-level modulated by Milankovitch-scale (c. 125 kyr) eustatic cycles. 'Flexural' events deformed the strata into troughs and arches across narrow zones of flexure. Arch crests were bevelled off, probably by submarine wave erosion. Eroded sediment did not accumulate in troughs but was advected beyond the study area by storm-driven processes. Cycles of deposition, warping and erosion were repeated five times on an average timescale of 600 kyr. Arches and troughs do not coincide with Precambrian basement structures, and their origin remains enigmatic. Changes in in-plane stress may have effected the localized vertical motion. [ABSTRACT FROM AUTHOR]

Upper Cretaceous ammonites are described from six horizons in the mammal-bearing terrigenous-clastic sequences of western Uzbekistan, as follows: Upper Cenomanian, with Placenticeras sp. juv. cf. cumminsi Cragin, 1893 and Metoicoceras geslinianum (d'Orbigny, 1850); Lower Turonian with Tragodesmoceras cf. mauryae Kennedy and Wright, 1981, Placenticeras kharesmense (Lahusen, 1884), Watinoceras coloradoense (Henderson, 1908), Watinoceras amudariense (Arkhangelsky, 1916b), Metasigaloceras rusticum (J. Sowerby, 1823), Morrowites wingi (Morrow, 1935), Sciponoceras cf. bohemicum bohemicum (Fritsch, 1872), and Yezoites amudariensis (Arkhangelsky, 1916b); Middle Turonian with Collignoniceras woollgari woollgari (Mantell, 1822); Upper Turonian with Lewesiceras mantelli (Wright and Wright, 1951) and Placenticeras crassum Ilyin, 2020; a single Placenticeras semiornatum (d'Orbigny, 1850) from around the Coniacian/Santonian boundary, and Santonian Placenticeras polyopsis (Dujardin, 1837). [ABSTRACT FROM AUTHOR]

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This study is conducted on the Northern Borders Province, northernmost Saudi Arabia, mapping a newly identified Wadi Al Khirr transtensional fault zone, based on detailed fieldwork, image interpretation as well as GIS work. The Wadi Al-Khirr fault zone extends from west of Al Uwayqilah to Zahwah. Remote sensing satellite data indicate that it can be projected further to the south toward the central Arabian Shield. About 100 km to the east of the newly proposed fault zone, late Cretaceous Linah Formation is changing its eastern lithofacies within the Widyan basin. The changes in lithofacies represent the results of tense diagenetic alteration (many phases of dolomitization/de-dolomitization), accompanied by silicification and carbonate leaching of the carbonate rocks. This western (Mediterranean) and eastern (Arabian Gulf) lithofacies appear to be laterally equivalent in biostratigraphy as it is evidently having Loftusia sp. in both sides. The lithofacies changes occur 100 km to the east of the Wadi Al Khirr fault zone; therefore, it is likely postdating the Upper Cretaceous sequences and may not be associated tectonically with the east to west lithofacies. The Sirhan–Turayf and Widyan basins' boundary is found in this study to have complicated tectonic setting. Wadi Al Khirr fault zone to the east, and the Makkah-Madinah-Nafud with newly interpreted Sakaka lineaments to the west bound the Ha'il arch, separating the two basins. Moreover, the Ha'il arch is cross-cut and deformed by Ar'Ar arch in the upper northern part of the study area and by reactivation of Najd Faults to the south. [ABSTRACT FROM AUTHOR]

Numerous representatives of the genus Patellula Kozlova, 1972 were studied from the Upper Cretaceous deposits of Perapedhi, Kannaviou and Lefkara formations (Cyprus). Two new species were described: Patellula mangaleniensis sp. nov. and Patellula solaris sp. nov. The species P. mangaleniensis was found in Crimea within the Afens perapediensis Zone (upper part of the Upper Santonian). The earliest representatives of Patellula euessceei Empson-Morin, 1981 were for the first time found in the Upper Cretaceous of Crimea, within the Actinomma (?) belbekense Zone (upper part of the Middle Turonian–Upper Turonian), while the latest representatives of P. euessceei were for the first time detected in the Maastrichtian of Cyprus. The stratigraphic ranges of Patellila euessceei and the genus Patellula are expanded. [ABSTRACT FROM AUTHOR]

Cretaceous deposits containing pelagic red beds (CORBs - Cretaceous Oceanic Red Beds) are developed in the Ukrainian Carpathians. CORBs have a global distribution, they are sharply depleted in organic matter and their formation is associated with periods of cooling and intensive circulation of cold, oxygen-enriched deep-sea currents that oxidize organic carbon. CORBs in the Ukrainian Carpathians are common in the Upper Cretaceous, while the Lower Cretaceous sediments, especially in the Outer (Flysch) Carpathians, are often enriched in organic matter (in particular the black shales of the Shypot and Spas formations). Such change in sediments enriched and depleted in organic matter may be associated with regular climate changes. In the Inner Carpathians, in the both the Peniny Klippen Belt and the Marmarosh Klippen Zone, CORBs are represented by thick (100-200 m) mostly red-colored marls and shales that make up the Turonian - Maastrichtian Puchov Formation. A fragment of the Puchov Formation of the Turonian age is presented in the Marmarosh Massif. Stratigraphically, the lowest CORBs represented by layers of pink marls are noted in the upper part (Middle-Upper Cenomanian) of the Tysalo Formation in the Peniny Klippen Belt. Deposits containing CORBs in the Peniny Klippen Belt are intensively deformed, in some places they are transformed into thin shale rocks or friction mud and are part of the tectonic mélange, while in the Marmarosh Klippen Zone they lie monoclinally and are weakly deformed. In the Outer Carpathians, CORBs are represented by: Turonian-Paleocene variegated shales and marls of the Holyatyn Beds (Subsilesian Nappe); Turonian-Coniacian red-colored and variegated shales belonging to the lower member of the Yalovets Formation (Dukla, Chornohora, Svydovets, and Krasnoshora nappes); and pack of Turonian variegated marls included in the Sukhiv Formation (Burkut nappe). CORBs represented by red-brown interlayers, occur both in the uppermust Albian-lower Cenomanian (Eiffellithus turriseiffeli Zone) of the Sukhiv Formation, and in the Santonian upper member of the Yalovets Formation. CORBs in the Outer Carpathians are deformed to a greater or lesser extent, plastic marls of the Sukhiv Formation are especially strongly deformed, which makes it much more difficult to establish their stratigraphic sequence. The age of the deposits of the Ukrainian Carpathians, which contain CORBs, has been clarified. The studied sediments are correlated with the Geologic Time Scale (2020) on the basis of nannoplankton and planktonic foraminifera. The biozonal scale based on nannoplankton of A.M. Romaniv is compared in the range BC27/UC0 (upper Albian - lower Cenomanian) - UC20 (upper Maastrichtian) according to the first appearance of zonal species according to the scale of J. Barnett (1998). Accordantly, the Eiffellithus turriseiffeli Zone (uppermost Albian-Lower Senomanian); Gartnerago obliquum Zone (Middle Senomanian-lowermost Turonian); Eiffellithus eximius-Marthasterites furcatus Zone (Lower Turonian-lowermost Upper Coniacian); Micula staurophora-Tetralithus obscurus-Broinsonia parca Zone (Upper Coniacian-lowermost Middle Campanian); Tetralithus aculeus Zone (Middle Campanian); Tetralithus? trifidus (Middle Campanian-lowermost Upper Campanian); Nephrolithus frequens (Upper Campanian-Upper Maastrichtian) are distinguished. The biozonal division of the Upper Cretaceous of the Carpathians according to planktonic foraminifera after N.I. Maslakova was modified and compared with the biochronozones of a typical section of the Tethys region (Coccioni, Premoli Silva, 2015). In the studied sediments, the following zones are distinguished: Thalmanninella reicheli (middle part of the Lower Cenomanian), Rotalipora cushmani (middle part of the Lower Cenomanian-Upper Cenomanian), Helvetoglobotruncana helvetica (lower part of Turonian), Dicarinella concavata (top of Turonian-lowermost Santonian), Contusotruncana fornicata (most of Santonian), Globotruncanita elevata (lower part of the Campanian), Contusotruncana morozovae (middle part of the Campanian), Globotruncanita stuarti (top of the Campanian-lower part of the Maastrichtian), Abathomphalus mayaroensis (upper part of the Maastrichtian); beds with Thalmanninella globotruncanoides (lower part of the Lower Cenomanian), assemblage with Marginotruncana schneegansi, Marginotruncana sigali, Marginotruncana renzi (upper part of Turonian). Benthic foraminifera Uvigerinammina jankoi Zone (Turonian); Spiroplectinella costata Zone (Coniacian-Lower Santonian); Caudammina gigantea Zone (Upper Santonian-Lower Campanian); Rzehakina inclusa Zone (Upper Campanian-Maastrichtian); Rzehakina fissistomata Zone (Paleocene) were identified accordantly to zonal schemes of L.D. Ponomaryova and B. Olszewska. The lower boundary of the CORBs in the Ukrainian Carpathians is correlated with the Senomanian-Turonian boundary on the basis of appearance of planktonic foraminifers of Helvetoglobotruncana helvetica Zone and benthic foraminifers of Uvigerinammina jankoi Zone in the base of both Puchov Formation (Pieniny Klippen Belt) and Holyatun Beds (Subsilesian Nappe), as well as in the lowermost part of the Yalovets Formation (Dukla, Chornohora, Svydovets and Krasnoshora nappes). [ABSTRACT FROM AUTHOR]

A study on depositional environment, diagenetic history, and sequence stratigraphy of the upper Cretaceous successions of the boundary between the Central and Eastern Alborz zones is lacking. This study attempts to tackle this issue by analyzing a succession composed of 120 meters of medium-to thick-bedded limestones. Facies analysis led to the identification of facies associations of terrestrial, inner ramp (proximal, mid, and distal lagoon and shoal), mid ramp, outer ramp, and basin settings. According to the lateral and vertical changes in facies associations indicating gradual facies variations and the absence of large barrier reef organisms, a carbonate platform of ramp type with a bioclastic shoal is suggested for the studied succession. However, regarding the presence of turbidites in the transition of mid and outer ramp facies, a distally steepened ramp better suits the studied succession. Diagenetic study reveals products of eogenesis, mesogenesis, and telogenesis stages. Sequence stratigraphic analysis based on facies analysis and field observation denoted one 3rd-order depositional sequence, which its maximum flooding surface is equivalent to MFS K180 of the Arabian Plate (AP) with middle Maastrichtian age. A disconformity at the topmost of the studied succession correlates with the upper sequence boundary of megasequence AP9 around the Cretaceous-Paleogene boundary. [ABSTRACT FROM AUTHOR]

We analysed the stable isotope compositions of dinosaur eggshells and their associated depositional settings of the egg-bearing rocks in the Upper Cretaceous of the Qiyunshan area, Anhui Province, China. Data show that δ13C values for Similifaveoloolithus qiyunshanensis and Umbellaoolithus xiuningensis range between −5.94‰ and −3.55‰; this suggests that C3-type vegetation was consumed by dinosaurs with relatively high atmospheric CO2. δ18O values vary between −8.45‰ and −4.95‰, indicative of high temperature and low humidity within nesting areas. The lithological characteristics of the egg-bearing section evaluated in this study are dominated by red-brown fine sandy siltstone, correlating with pebbly medium-fine grained and medium-fine grained lithic sandstones. Grain size parameters, histograms, and sample probability cumulative curves are also all characterised by fine-grained sediments and suspension populations, likely indicative of floodplain and point bar environments. Therefore, the paleoclimate of the dinosaur nesting habitat was semiarid-to-arid based on food types as well as the colour and high Fe content of sediments. We suggest that this fluvial environment provided the best nesting and egg laying area for drought-adapted dinosaurs in the Upper Cretaceous of the Qiyunshan area and that the excavated nesting could be concluded in view of the periodic flooding events. [ABSTRACT FROM AUTHOR]

The study of microfacies, with special emphasis on the significance of larger benthic foraminifera, is used to interpret the occurrence of different marine subenvironments into a mixed carbonate-siliciclastic platform from the upper Campanian in the Prebetic domain, representing the southeastern margin of the Cretaceous Iberian paleoisland. Four foraminiferal assemblages have been recognized, each one specifically assigned to a depositional systems: (1) the outer to middle shelf with Neorotalia? pinetensis, Goupillaudina spp., gavelinellids, Orbitoides tissoti-media, Praesiderolites douvillei, and Navarella joaquini; (2) the upper part of the middle shelf with the presence of seagrass meadows Orbitoides tissoti-media, "Orbitoides" concavatus, Lepidorbitoides campaniensis, Planorbulina cretae, Sirtina ornata, Praesiderolites douvillei, Pseudosiderolites vidali, and Rotalia baetica; (3) the upper photic zone of the inner shelf, with constant wave agitation, inhabited by Orbitoides cf. megaloformis, Lepidorbitoides campaniensis, and Wannierina vilavellensis; and (4) the paralic shallow protected shelf with alternating marine/freshwater influences characterized by charophytes and Suturina minima. Results on larger foraminifera distribution show the similarities and differences with the benthic communities shallow water platform assemblages of the nearby Pyrenean paleobioprovince. This allows to rise the Upper Cretaceous shelfs of the Betic area as a fundamental biogeographic piece for larger benthic foraminifera migration patterns between the Tethyan domain and the other marine domains during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

The taxonomic typification of dinocyst assemblages was carried out on the basis of a qualitative and quantitative assessment of their generic composition for the Northern Hemisphere in the Cenomanian–Turonian time to identify correlation taxa. Three types of dinocyst assemblages were identified in the Cenomanian. Cenomanian dinocyst assemblages are poorly differentiated; a large number of cosmopolitan genera were identified, which is in good agreement with paleobotanical data indicating a very warm, humid climate. Three types of dinocyst assemblages were established for the Turonian. The number of cosmopolitan dinocyst genera decreases and species endemism sharply increases in some Turonian basins. The differentiation of assemblages increases and their correlation potential decreases. However, the identified common genera and species of dinocysts in different types of assemblages provide the possibility of interregional correlation of Upper Cretaceous deposits at the stage, substage, and, at some sections, even more detailed levels in different climatic zones. [ABSTRACT FROM AUTHOR]

A systematic-stratigraphic revision of selected large Late Turonian–Early Coniacian inoceramids of the lamarcki group from Germany showed that both historical specimens of Goldfuss (1836), introduced as Inoceramus annulatus and later becoming the types of Late Turonian I. lamarcki stuemckei Heinz, 1928a and Early Coniacian I. annulatus Goldfuss, 1836, respectively, are of Late Turonian age. I. stuemckei Heinz, 1928a, as emended herein, is well represented by its lectotype. Bulky isolated hinges from Upper Turonian strata, used by Heinz (1932a) to erect Heroceramus hercules, are just fragments of contemporaneous large I. stuemckei; H. hercules is thus invalid. The common Late Turonian I. stuemckei occurs facies-independent from near- to offshore settings and its first common appearance is an excellent marker for the substage base. I. annulatus Goldfuss, 1836 was later applied to very large forms first appearing in the mid-Early Coniacian. Thus, I. annulatus sensu Walaszczyk and Wood (1998) is poorly represented by its medium-sized latest Turonian lectotype, causing some nomenclatorial issues. I. stuemckei (heightmax 500 mm) and I. annulatus (heightmax one metre) are characterized by a stratigraphically abrupt shell enlargement and hinge buttressing across the Middle/Upper Turonian boundary and within the Early Coniacian, respectively. This shift to larger sizes, a common passive defense strategy against predation, is accompanied by widespread evidence for increased Late Turonian predation pressure by marine durophages. We thus speculate that the size increase in Late Turonian–Early Coniacian inoceramid bivalves is part of an escalating arms race between prey and predators, ultimately triggering Late Cretaceous inoceramid gigantism. [ABSTRACT FROM AUTHOR]

The Anambra Basin has a relatively high hydrocarbon production base compared with other Cretaceous basins in Nigeria. Structural deformation, overpressures, and faulting in the Cretaceous sequence of the Anambra Basin have resulted in significant uncertainties regarding reservoir parameters, necessitating accurate reservoir characterization. This study uses several subsurface data, including 2D seismic data, a report of core descriptions, and well log data from an exploration well drilled in the Anambra Basin to identify reservoirs and assess the petrophysical parameters of Cretaceous Formations for hydrocarbon accumulations. Three reservoirs were identified in the interpreted seismic section of the Cretaceous strata, and the structural framework was described as a system of synthetic faults dipping north-south that controlled the thickness and lateral extension of the deposited sediments. The shale volume, total and effective porosity, permeability, water, and hydrocarbon saturation were estimated using standard equations. The low shale volume, good-to-very good porosity values, fair-to-moderate permeability values, and low-tomoderate hydrocarbon saturation of the identified Cretaceous reservoirs suggest that the reservoir sands have the capacity to produce hydrocarbons. The density-neutron cross-plots of the identified reservoirs show a dual mineral system and also indicate the effect of gas in the Cretaceous reservoirs. This study found that the Anambra Basin has gas potential. However, the identified gas reservoirs should be further evaluated using reservoir pressure data, if available, to aid in accurate hydrocarbon fluid typing. The reservoirs should be developed and optimized in such a way as to keep production risk to its minimum. [ABSTRACT FROM AUTHOR]

We investigated the palynological organic matter (POM) recovered from shale horizons, intercalating the Nubian-type sandstones in middle Egypt, for paleoenvironmental reconstruction. Our palynofacies are dominated by either amorphous organic matter (AOM) or phytoclasts whereas palynomorphs are relatively rare, but not uncommon. The palynofacies categories revealed two different palynofacies types, reflecting estuarine/tidal and fluvio-lacustrine environments for the Maghrabi and the basal Quseir formations, respectively. The kerogen composition of our investigated material and the colors of the thin-walled spores suggest possible sources of hydrocarbons, which are poorly explored in the middle and southern areas of Egypt. Our findings confirmed the previously described marine origin of the Maghrabi Formation. The complete missing of any marine palynomorphs suggests that the basal sediments of the Quseir Formation are almost exclusively of terrestrial origin. This may reveal that the worldwide Late Cretaceous transgression was not effective during deposition of these basal clastics. [ABSTRACT FROM AUTHOR]

Umenocoleidae is an enigmatic, extinct Mesozoic beetle-like roach family with cosmopolitan distribution erroneously attributed to various insect orders by past authors. Here unusual and well-preserved Archaeospinapteryx tartarensis gen. et sp. n., Trapezionotum vrsanskyi gen. et sp. n., Poikiloprosopon celiae gen. et sp. n., Vzrkadlenie karneri sp. n., and V. saintgermaini sp. n. are described from Cenomanian Burmese amber of the Hukawng Valley. Furthermore, Nigropterix angustata gen. et sp. n. and Umenotypus maculatus gen. et sp. n. are reported from Turonian sediments of Kzyl-Zhar, Kazakhstan. ?Classopolis pollen grains directly attached on the frons of the head of one specimen indiciate pollen transfer, as reported in other representatives of Umenocoleoidea. The herein studied material increases our knowledge of the diversity of this bizarre lineage and extends its temporal and paleogeographic distribution. [ABSTRACT FROM AUTHOR]

The Blattulidae Vishniakova, 1982 is an extinct family of cockroaches which was widely distributed around the world from Late Triassic to Late Cretaceous. Huablattula vrsanskyi sp. n., based on a well-preserved specimen from mid-Cretaceous Kachin amber differs from other species of genus Huablattula Qiu et al., 2019 in having different patterns on the pronotum, forewing with vein A bifurcated and hind wing without pterostigma. The new discovery enriched the diversity of the family Blattulidae in Kachin amber and expanded our understanding of cockroach structure and phylogeny. [ABSTRACT FROM AUTHOR]

Field observations, together with the results of gas chromatography–mass spectrometry (GC-MS) and stable carbon isotope analysis of bitumen, coupled with fluid inclusion microthermometry and stable isotope analyses of closely associated vug- and fracture-filling columnar calcite in the Upper Cretaceous Bekhme Formation, Kurdistan Region of Iraq, suggest that the degradation of crude oil was caused by the regional incursion of meteoric waters. This incursion, which is interpreted to have occurred during tectonic uplift during the Zagros Orogeny, is evidenced by: (i) the depletion of n-alkanes and acyclic isoprenoid alkanes (pristane and phytane) in the bitumen; (ii) low δ13CVPDB values (−8.5‰ to −3.9‰) and δ18OVPDB values (−22.9‰ to −15.0‰), with more radiogenic Sr isotopic ratios (0.70771–0.70772) compared to Cretaceous seawater; and (iii) low salinity and low temperatures (20 to 40 °C) in fluid inclusions of the columnar calcite. This study demonstrates that regional meteoric water incursion into sedimentary basins can be linked to crude oil degradation accompanied by calcite cementation events in carbonate reservoirs. [ABSTRACT FROM AUTHOR]

Nanhsiungchelyidae are a group of large turtles that lived in Asia and North America during the Cretaceous. Here we report a new species of nanhsiungchelyid, Nanhsiungchelys yangi sp. nov., from the Upper Cretaceous of Nanxiong Basin, China. The specimen consists of a well-preserved skull and lower jaw, as well as the anterior parts of the carapace and plastron. The diagnostic features of Nanhsiungchelys include a large entire carapace length (~55.5 cm), a network of sculptures consisting of pits and ridges on the surface of the skull and shell, shallow cheek emargination and temporal emargination, deep nuchal emargination, and a pair of anterolateral processes on the carapace. However, Nanhsiungchelys yangi differs from the other species of Nanhsiungchelys mainly in having a triangular-shaped snout (in dorsal view) and wide anterolateral processes on the carapace. Additionally, some other characteristics (e.g., the premaxilla is higher than wide, the maxilla is unseen in dorsal views, a small portion of the maxilla extends posterior and ventral of the orbit, and the parietal is bigger than the frontal) are strong evidence to distinguish Nanhsiungchelys yangi from Nanhsiungchelys wuchingensis. A phylogenetic analysis of nanhsiungchelyids places Nanhsiungchelys yangi and Nanhsiungchelys wuchingensis as sister taxa. Nanhsiungchelys yangi and some other nanhsiungchelyids bear distinct anterolateral processes on the carapace, which have not been reported in any extant turtles and may have played a role in protecting the head. The Nanxiong Basin was extremely hot during the Late Cretaceous, and so we suggest that nanhsiungchelyids might have immersed themselves in mud or water to avoid the heat, similar to some extant tortoises. If they were capable of swimming, our computer simulations of fluid flow suggest the anterolateral processes could have reduced drag during locomotion. [ABSTRACT FROM AUTHOR]

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Two isolated metatarsals (III and IV) of theropod dinosaurs from the Bostobe Formation (Upper Cretaceous, Santonian–Campanian) of the Shakh-Shakh locality in Kazakhstan are assigned to the representatives of the families Caenagnathidae and Dromaeosauridae, respectively. The metatarsal III of Caena-gnathidae indet. confirms the presence of oviraptorosaurs in the dinosaur assemblage from the Bostobe Formation. This bone is very similar morphologically with the metatarsal III of Elmisaurus rarus Osmólska, 1981 from the Maastrichtian of Mongolia. The metatarsal IV of Dromaeosauridae indet. is characterized by a lateral crest, which among dromaeosaurids is known only for Velociraptor mongoliensis Osborn, 1924 from the Campanian of Mongolia. [ABSTRACT FROM AUTHOR]

The "Marrón Emperador" ornamental stone is known for its characteristic deep brown colour filled with white spots and veins. It consists of a brecciated dolostone with different generations of calcite/dolomite veins and veinlets that represent repeated episodes of fracture opening and partial or complete cementation, which likely corresponds to individual stages of fluid expulsion. Mineralogical, petrographic and geochemical studies point to the formation of these rocks through brecciation, dolomitization and rapid cementation processes in an active tectonic regimen. The composition and textural features of the stratiform dolomite geobody point to a structurally controlled dolomitization model. The overall breccia geometry, breccia texture and vein characteristics are all consistent with a brecciation origin driven by hydraulic fracturing, with subsequent calcite precipitation in open space and partial solution replacement of clasts. A paragenetic sequence includes: (1) marine sedimentation of original tidal carbonate sediments; (2) early lithification and marine cementation; (3) burial diagenesis with early fracturation of limestones; (4) entrance of dolomitizing fluids through fractures causing pervasive dolomitization (brown dolostones) and dolomite cements (fracture-lining and saddle dolomites); (5) fracturation by hydraulic overpressure under an active tectonic regime; (6) calcite cementation (white veins and veinlets); and (7) uplift and meteoric diagenesis producing dedolomitization, karstification and local brecciation. [ABSTRACT FROM AUTHOR]

In the Lower Campanian, Pachydiscus (Pachydiscus) launayi (De Grossouvre) was found for the first time above a soap (bentonite) clay layer, which has been described well in the literature, in an abandoned quarry on the outskirts of Kudrino village in Southwestern Crimea. This finding expands our understanding of the distribution of this species and precises the biostratigraphic position of the soap clay layer. [ABSTRACT FROM AUTHOR]

Alkaline dikes from the Santos-Rio de Janeiro coast, SE Brazil, mainly from São Sebastião and Búzios islands, yielded a Late Cretaceous paleomagnetic pole (SR) located at 319.7°E 81.2°S (N = 44, A95 = 3.0°, k = 44). This pole includes some sites of alkaline stocks from São Sebastião Island of the same age and supersedes the previous pole for this island. To match the available radiometric ages and the prevailing normal polarity remanence of the rocks with the geomagnetic polarity time scale, the SR pole is placed at 84 Myr. Another group of alkaline rocks, dikes located mainly in Rio de Janeiro, was assigned an age of less than 70 Myr. The ages of the Poços de Caldas, Itatiaia, and Passa Quatro paleomagnetic poles are also discussed based on available radiometric data. Assuming a rigid plate, the SR pole indicates the southward movement of about 7° with virtually no rotation between 100 and 84 Myr. From approximately 84 to 70 Myr, a clockwise rotation of 8° is postulated, with slight variation in latitude. [ABSTRACT FROM AUTHOR]

Studies of the paleopathology of the vertebrae provide an interesting, oblique approach to their paleobiology and even paleoethology. They tell us about possible ethological causes such as accidental blows with objects, social interactions within a group, and defense against predators, etc. There are numerous works on the anatomical and phylogenetic aspects of sauropod dinosaurs, and in recent years paleopathological studies have also increased. Here, we describe the injuries recorded in the caudal vertebrae of two indeterminate titanosaurids, and undertake a compilation and analysis of the pathological fossil record worldwide, focusing on the tails of sauropods. Two pathologies have been identified as present in the indeterminate titanosaurids under study: a possible case of spondyloarthropathy in MAU-Pv-LI-601, and a case of suppurative spinal osteomyelitis in MAU-Pv-LJ-472/1. Both titanosaurids are from Gondwana. In the world registry of pathologies associated with the tails of sauropod dinosaurs, it is observed that titanosaurs are the sauropods with the highest percentage of diagnosed pathologies (69% including the two new records from the province of Neuquén) and that all of these have been described in Gondwanan specimens. [ABSTRACT FROM AUTHOR]

Delta-plain strata of the Cenomanian Dunvegan Formation, in north-east British Columbia, represent anastomosed rivers that were flanked by vegetated crevasse splays, wetlands and shallow lakes. These rocks preserve a rich record of ankylosaur and ornithopod walking and wading tracks, as well as crocodylian swim traces and tracks. Analysis of depositional, erosional, and trace-making events reveals alternating phases of flooding and emergence that controlled both animal activity (walking, wading, swimming) and mud substrate consistency (firm vs. soupy), and hence fidelity of track preservation. Some tracks resemble those produced by both ankylosaurs and crocodylians, and confident attribution is difficult. The absence of tail drag marks suggests an ankylosaur trackmaker, whereas prominent claw marks might favour a crocodylian origin. Unusually large crocodylian swim traces suggest animals about 9 m, and possibly up to 12 m in length. These large traces may represent a precursor to the giant crocodylian Deinosuchus. Ankylosaur tracks are well-preserved in lake and channel-margin deposits, whereas crocodylian traces are most commonly preserved in firm muddy lake sediments that had experienced previous subaerial exposure and dewatering. Close integration of trace fossils with sedimentary and stratigraphic features makes it possible to reveal a detailed chronology of biotic and sedimentary events on palaeo-surfaces. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous (Turonian) Bissekty Formation of Uzbekistan has yielded many isolated bones and teeth representing a variety of non-avian theropod dinosaurs. A pedal phalanx II-2 indicates the presence of a dromaeosaurid theropod that attained a larger body size than any previously known member of that clade. The same formation also yielded a large maxillary fragment that has recently been described as a neovenatorid carcharodontosaurian (Ulughbegsaurus uzbekistanensis). However, this specimen lacks unambiguously diagnostic features of that clade, and its purported carcharodontosaurian characters are either taphonomic artefacts or also shared by dromaeosaurids. Thus, the phylogenetic relationships of Uleghbegsaurus uzbekistanensis remain uncertain. A giant dromaeosaurid occurred together with the medium-sized tyrannosauroid Timurlengia euotica in the Bissekty assemblage. [ABSTRACT FROM AUTHOR]