Jurassic - Science topic

Retene and dehydroabietic acid methyl ester (DAME) are biomarkers linked mostly to terrigenous organic matter. However, their aquatic origin from algae and/or cyanobacteria has been discussed in the past few years. The complex origin of retene and DAME can lead to misinterpretation during biomarker interpretation, which can be minimalised with the...

The Cintura Formation is the youngest formation of the Bisbee Group (Lower Cretaceous), whose type locality is the Cintura Hill in southeastern Arizona. The Cintura Formation exposed in the Sonora state of Mexico has been divided into three informal stratigraphic members, which from base to top are: Marquechi, San Marcos, and San Juan, respectively...

Lower Jurassic marine basins across the northwest European epicontinental shelf were commonly marked by deposition of organic-rich black shales. Organic-carbon burial was particularly widespread during the Toarcian Oceanic Anoxic Event (T-OAE: also known as the Jenkyns Event) with its accompanying negative carbon-isotope excursion (nCIE). Lower Toa...

The Jurassic Shaximiao Formation in the Sichuan Basin represents a significant tight gas reservoir, exhibiting marked permeability variations between the southern and northern regions of western Sichuan. This study examines the reservoir characteristics of the Shaximiao Formation, with a focus on the evolution of sandstone porosity under bidirectio...

Ithonidae (moth lacewings) are an enigmatic, small family of the insect order Neuroptera (lacewings). Its phylogenetic position within Neuroptera and internal subfamily relationships remain unresolved. In this study, the complete mitochondrial genome (mitogenome) of Ithone fulva Tillyard, 1916 representing the first mitogenome of Ithoninae, as well...

Deep coalbed methane (CBM) resources are abundant in China, and in the last few years, the country’s search for and extraction of CBM have intensified, progressively moving from shallow to deep strata and from high-rank coal to medium- and low-rank coal. On the other hand, little is known about the gas content features of deep coal reservoirs in th...

A comprehensive geochemical analysis for the Sargelu, Naokelekan, and Najmah formations cutting rock and crude oil samples from Z1, Z3, and Z5 wells of Hawler Block, Kurdistan Region, Iraq have been studied for source rock evaluation. Depending on the total organic carbon (TOC) content from pyrolysis analyses, the Sargelu and Naokelekan formations...

The research focuses on structural geological mapping and fracture analysis of part of Kala-Chitta Range, Himalayan foothills, northern Pakistan. The area exhibits complex geological settings characterized by intense deformation with eight litho-stratigraphic units ranging from the Late Jurassic to Paleocene. The outcropping rocks have well recorde...

The knowledge of Pliensbachian (Early Jurassic, ∼192.9-184.2 Ma) plesiosaurs is notoriously insufficient. Although there have been specimens described from different parts of the world, only three of them have been established as diagnosable taxa. Here, we describe two previously unreported lower Pliensbachian plesiosaur occurrences that originate...

The Toarcian lacustrine deposits of the Sichuan Basin (China) are represented mainly by silty marlstones and bivalve rich limestones disposed in decametric-scale thickening upwards sequences. Dense accumulations of bivalve shells are related to episodes of mass mortality under oxygen depleted conditions in the bottom waters. The geochemical detrita...

Distinct, new oviposition lesion types, Paleoovoidus pyriformis ichnosp. nov. and Variomorphonotatus sagittaeformis ichnogen. et ichnosp. nov., occurring on two fossil compression Cycadophyte leaves from the Lower Jurassic Shemshak Formation of western Alborz Ranges, northern Iran are documented and compared with the previously instituted morpholog...

The structure of the Tajik Basin is characterized by a series of NE-trending foldthrust belts that share a common detachment layer composed of Upper Jurassic evaporite rocks. These fold-thrust structures, thrusting face to face, converge toward the Vakhsh Depression. Due to limitations of seismic and drilling data, the controlling factors of the fo...

The area of the city of Shenzhen at the Pearl River Delta in Guangdong Province, China, comprises rocks that preserve, with few interruptions, around 1.8 billion years of geological history. However, to date, only few scientific studies within a palaeontological context have been conducted on the sediment rocks in Shenzhen. Herein, the fossil recor...

Radiolarians are rock-forming constituents of siliceous beds of the Bazhenovo Formation in Western Siberia. Studying radiolarians is necessary for stratigraphy and correlation of the organic-rich Bazhenovo Formation, as they provide reliable dating of productive intervals of the section and detailed stratigraphy and zonation, which is especially im...

Late Tithonian (Late Jurassic) palaeobotanical records from the Jaisalmer Basin are infrequent. We report the first record of an age-diagnostic palynological assemblage of the sedimentary rocks in the Bhadasar Formation from the Jaisalmer Basin, India. The study is carried out to consider the palaeoenvironmental settings in this basin based on paly...

To reveal the shale oil occurrence state and its controlling factors of the Jurassic Lianggaoshan Formation in the Sichuan Basin, experimental analyses, including total organic content, X-ray diffraction, low-temperature nitrogen adsorption-desorption, nuclear magnetic resonance, conventional, and multistage rock-eval, were conducted on the shale s...

One of the five greatest mass extinction events in the history of life occurred at the end of the Triassic (~ 201 million years ago), as confirmed by profound loss of life in marine realm. Terrestrial ecosystems were also suffered but the extent of life loss and timing of subsequent recovery remain equivocal, largely because of scarcity of fossil r...

The paper deals with the research of mineralogical composition of clay fraction of rock samples, injection of different water in the fields of Western Siberia, analyzed well performance. It was found that the final oil recovery of reservoirs at reservoir pressure maintenance by water injection is significantly affected by the swelling of clay miner...

Проведен анализ основных представлений о стратиграфическом объеме тоарского яруса на Северо-Востоке Азии с позиции концепции исторической динамики науки. Показано, что, несмотря на детальные исследования нижне-среднеюрских отложений, проводившиеся более ста лет, и создание биостратиграфического каркаса стратиграфических схем, остаются нерешенными н...

Материалом для проведения ревизии системы семейства Oxytomidae (подсемейства Oxytominae) являлись собственные и музейные коллекции из мезозойских отложений, собранные на разных стратиграфических уровнях. С помощью метода возрастной периодизации получены представления об изменчивости лигаментного и биссусного блоков раковин в онтогенезе моллюсков. К...

The planform is a defining feature of mantle convection. It can be gleaned from the stratigraphic record by mapping the continent-scale distribution of hiatus and no hiatus surfaces serving as a proxy for high and low dynamic topography. We carry this out for all continents apart from Antarctica for eight geological series since the Upper Jurassic,...

Genome size is an adaptive trait, and its variations influence the organismal phenotype and fitness. In this study, we propose a hypothesis linking variations in genome size within Scolopendra to ecological factors. To test this hypothesis, we employed flow cytometry to estimate genome size in seven Scolopendra species from Chinese mainland. Subseq...

Desert dust is a key component of the climate system, as it influences Earth's radiative balance and biogeochemical cycles. It is also influenced by multiple aspects of the climate system, such as surface winds, vegetation cover, and surface moisture. As such, geological records of dust deposition or dust sources are important palaeoclimate indicat...

The evolution of Jurassic carbonates is globally significant for understanding the depositional framework, diagenetic phases and sedimentary characteristics of shallow marine shelf deposits. For this purpose, two outcrop sections of the Jurassic carbonates with a road distance of 121 km in the Trans Indus Ranges, NW Himalayas, were included in this...

This study analyzes 105 coal ash samples from Jurassic and Carboniferous coals from five mines in Kazakhstan, Lenin, Saradyr, Bogatyr, Maikuben, and Shubarkol, focusing on the inorganic elemental compositions, their occurrence, and industrial and environmental implications. Methods include coal ash yield and volatile matter analysis, mineralogical...

The China-Pakistan Economic Corridor (CPEC) has sparked a significant construction boom in Pakistan, driving a critical need for diverse natural aggregate sources. This research seeks to discover new sources of high-quality construction materials, enhancing concrete performance and fulfilling the need for sustainable building resources. The researc...

The lower Triassic Main Buntsandstein Subgroup represents a promising, but high-risk geothermal play in the Netherlands. Although the gross thickness in boreholes locally exceeds 200 m, the spatial distribution, geometries and preservation of these sedimentary units remained uncertain due to the lack of seismic data with sufficient resolution and t...

Hydrogen sulphide (H2S) concentrations across three adjacent gas condensate fields in Southwestern Gissar produced from fractured Middle-Upper Jurassic reef-carbonates with anhydrite-bearing beds have been analysed. Wellsite testing measurements followed by iodometric titration showed concentrations of H2S below 0.2 mole%. Statistical analyses and...

The Jurassic Lianggaoshan Formation in Yingshan-Pingchang region, northeastern Sichuan has great exploration potential for shale oil and gas resources. To better understand the control of natural fractures on oil and gas enrichment and reservoir production, this paper utilizes multi-scale fracture characterization methods such as field observation,...

Sciaroidea is a megadiverse clade within Diptera that exhibits diverse larval feeding modes. In this study, we explored the phylogenetic relationships and evolution of larval feeding modes within the superfamily using a fossil-calibrated time tree. We found that filtering out potentially fast-evolving sites altered the family-level tree topology, a...

Basin hydrology and subcrop are key controls on carbonate sedimentation in continental basins. Hydrologically sensitive carbonates can record groundwater fluctuations within an aquifer in deep time. Late Jurassic extension, footwall uplift, erosion and karstification of marine Jurassic carbonates in the western Cameros Basin (Spain) saw deposition...

As a result of sedimentological study of the Kimeridge-Berriasian interval rocks, characterized by core from wells, drilled in the Caspian Sea area in the Prikumskaya-Central-Caspian system of depressions and uplifts, lithotypifi cati on was carried out. Microfacial types were also identifi ed and facies were determined based on this data. It was e...

The development height of a water-flowing fractured zone is the key parameter to consider when carrying out mining under water pressure and coal mining with water conservation. In this paper, Jurassic coal seam 3-1 in the Menkeqing Coal Mine was taken as the research target, and a three-dimensional mining geological model was established by using F...

Early Jurassic mafic–ultramafic igneous rocks are sporadically exposed in the eastern part of northeastern China. Understanding their petrogenesis and geological implications is essential for elucidating the evolution of magma in subduction zones and the evolutionary history of the Paleo-Pacific Ocean. This study presents a detailed petrological, z...

Glauconite is an authigenic green mineral which has been studied extensively because its conditions of formation make it possible to evaluate certain parameters of the sedimentary environments where it is found. The most widespread view is that glauconite forms very slowly from a clay precursor, in environments where low sedimentation rates allow p...

Jurassic lacustrine shale in the Sichuan Basin is a focal exploration area in China, while the pronounced heterogeneity presents challenges, necessitating detailed research as a prerequisite. This study aims at the Jurassic Ziliujing Formation Da’anzhai shale in the central Sichuan Basin, systematically characterizing its geological features. Emplo...

The El Zorro gold district is the most recent gold discovery in the Coastal Cordillera of northern Chile. Ternera is the largest deposit in the district with total resources currently estimated at 1.282 Moz. New geology, geochemistry and geochronology data indicate that hydrothermal mineralization is mostly hosted within felsic to intermediate, ilm...

This spectacular mega erratic at Neuchâtel attracted many of the leading nineteenth-century British geologists who visited Switzerland. It was just one of numerous erratics on the Jura east facing slope. Its fascination revolved around the problem of how clasts of Mont Blanc granite sourced c.100 km away came to lie on Jurassic limestone bedrock. I...

Tight gas sandstone represents a significant unconventional resource extensively discovered across numerous sedimentary basins around the world. Tight sandstone reservoirs are characterized by low porosity, low permeability, variable source material, rapid spatial and temporal changes, poor reservoir properties, and strong heterogeneity. Traditiona...

In Raptors and Rapture: An Examination of Physical Threats and Theological Misinterpretations, we explore two distinct yet culturally resonant concepts—raptors, the predatory creatures that evoke primal survival fears, and the rapture, a theological construct deeply embedded in Christian eschatology. While the physical threat of a raptor, famously...

Leaf-associated fungi, the fungi that depend on leaves to sporulate, have a rich Cenozoic record, however their earlier diversity is poorly characterized. Here we describe Harristroma eboracense gen. et sp. nov., a Middle Jurassic leaf-associated fungus colonizing the leaf cuticle of Nilssonia tenuicaulis (cycadophyte). To place our newly described...

The biostratigraphy of the Jurassic in East Greenland is historically based on macroscopic fossils. Stratigraphy based on palynomorphs (spores, pollen and dinoflagellate cysts) has progressed more slowly and sporadically. The Scriniodinium crystallinum dinoflagellate cyst Zone is identified in middle – upper Oxfordian strata of Ilimananngip Nunaa (...

The shale sedimentary environment is crucial for evaluating shale gas reservoirs and sweet spot zones. The Xiahuayuan Formation in the Xuanlong Depression of the Yanshan area is an important exploration and development region for shale gas due to its multi-layer dark shale. The paleosedimentary environment and organic matter accumulation mechanism...

Stick and leaf insects are a group among the Insecta that are famous for their extraordinary mimicry ability. Since the establishment of the Phasmatodea, their internal classification has been constantly revised. Mitochondrial genes as molecular markers have been widely used for species classification, but the phylogenetic relationships within the...

During the Middle to Late Eocene (~45-35mya), Balkanatolia was an island continent comprised of modern-day Turkey and the Balkans. By this time, Balkanatolia had been isolated from mainland Europe and Asia for several million years since the end of the Paleocene. As a result, the endemic fauna was unique and included many distinct lineages not foun...

Since the last comprehensive review of the then state-of-the-art progress in paleomammalogy in 2010, there has been substantial further advances in understanding the middle ear development and phylogeny of Mesozoic mammals, evolution of early primates, and so on. The post-dentary bone morphologies of two Jurassic mammaliaforms, Dianoconodon youngi...

Understanding the biospheric response to climate change over evolutionary time scales is a paleontological endeavor. Dinosaurs offer a unique opportunity to examine continuous (>150 million years, Ma) responses to climate in a large clade of terrestrial tetrapods. Throughout the Mesozoic, multiple hyperthermal events influenced diversity, biogeogra...

The thiolliericrinids, although having a stem in the adult stage, are classified as comatulids (Comatulida) that are usually identified as stemless forms. They first appeared in the Bajocian (Middle Jurassic), and their last occurrence is noted in the Hauterivian (Early Cretaceous). Herein we report a thiolliericrinid crinoid from the Aptian of nor...

The mechanism for crustal thickening and superposition of several orogens is critical for understanding the growth of mountain ranges. Our study focuses on a trans-orogen crustal cross-section to revisit the Andean tectonic evolution in the Northern Central Andes (5◦-8◦S). It is based on a review of the geological setting, the definition of long-te...

Sargelu Formation from X Well, northern Iraq was studied to evaluate the hydrocarbon generation potential. To achieve this purpose, 15 rock samples were analyzed for Total Organic Carbon, Rock Eval pyrolysis and biomarkers analysis. The studied samples were classified as poor-excellent source rocks, in which they have Total Organic Carbon content i...

The history of study of the Upper Jurassic Volgian Stage and Lower Cretaceous Ryazanian Stage, their geographic occurrence, and use in world practice, subdivision, and correlation are considered. The data on the occurrence of various groups of macro-and microfossils (ammonites, bivalves, radiolarians, dino-cysts, and marine vertebrates) in the Volg...

Ring inversion structures are a phenomenon of geological structure of the northern regions of the West Siberian Basin. They include synclines in Jurassic sediments overlain by subtle uplifts in Cretaceous sediments. Interpretation of seismic data shows that these disharmonic structures probably resulted from salt diapir growth in Paleozoic sediment...

The M'goun UNESCO Global Geopark is located in the central part of the High Atlas Mountains in Morocco. Numerous studies have highlighted the richness of the geological heritage of this area. Despite these increased efforts in characterization, some areas, such as Anergui, remain underexplored. This mediation work aims to describe the most signific...

S’Albufereta de Pollença es troba situada al nord de l’illa de Mallorca, a l’extrem més meridional de la badia de Pollença. Es tracta d’una zona humida, amb una extensió de 400 ha que estructuralment ocupa una depressió postmiocena resultat de l’extensió distensiva, que tingué lloc després de la formació de la serra de Tramuntana a finals de l’olig...

UnambiguousPinaceae taxa are described from the Late Jurassic onwards. This fossil record does not, however, match the molecular estimates of deep divergence within Pinaceae. In recent years, new anatomical observations and revisions have reassigned several species of Schizolepis Braun to the emended genus Schizolepidopsis Doweld, 2001 Emend. Domog...

The Barremian-aged Wessex Formation of the Isle of Wight, UK, offers a globally significant glimpse into the sauropod dinosaur faunas of the early Cretaceous. These deposits have yielded specimens of several neosauropod lineages, such as rebbachisaurids, titanosauriforms (including some of the earliest titanosaur remains), and possible flagellicaud...

The upward continuation technique was applied to the gravity and magnetic data to obtain the residual anomalies maps in eastern Iraq. A new processing method is introduced to calculate the crustal layers depending on the relation between the total range of the residual anomalies of gravity, magnetic data and the upward continuation, with multi-elev...

Anurans are characterized by a biphasic life cycle, with an aquatic larval (tadpole) stage followed by an adult (frog) stage, both connected through the metamorphic period in which drastic morphological and physiological changes occur¹. Extant tadpoles exhibit great morphological diversity and ecological relevance², but their absence in the pre-Cre...

Dinosaurs potentially originated in the mid-palaeolatitudes of Gondwana 245–235 million years ago (Ma) and may have been restricted to cooler, humid areas by low-latitude arid zones until climatic amelioration made northern dispersals feasible ca 215 Ma. However, this scenario is challenged by new Carnian Laurasian fossils and evidence that even th...

Solid Earth CO2 outgassing, driven by plate tectonic processes, is a key driver of carbon cycle models. However, the magnitudes and variations in outgassing are poorly constrained in deep‐time. We assess plate tectonic carbon emissions and sequestration by coupling a plate tectonic model with reconstructions of oceanic plate carbon reservoirs and a...

Over the last decade, a large group of authors has been studying the fossils and biostratigraphy of the Djangura Formation (Bajocian – Lower Bathonian) in the interfluve of the Kuban and Urup rivers (Karachay-Cherkessia). This report provides information on the most unusual ammonite taxa found in this region.

This comprehensive study seeks to assess the upper Jurassic Alif reservoir within the Halewah oil field in the Marib-Shabwa (Sab’atayn) Basin of Yemen. The Halewah oil field is considered one of the most promising areas for petroleum production and is greatly favoured by exploration activities. The study’s data set consists of digitised wireline lo...

The Albanide-Hellenide belt includes two parallel NNW-SSE trending belts of Jurassic Tethyan ophiolites: the Vardar zone in the east and the Mirdita-Subpelagonian-Pelagonian (MSP) zone in the west (Saccani et al., 2011, 2017). The MSP ophiolites feature, in turn, two distinct belts with different lithostratigraphy and geochemistry: the western and...

Greywackes make up a substantial part of the Cadomian basement of Saxo-Thuringia. Here, their classification as greywackes and the timing of metamorphic overprint are re-evaluated using a multi-method approach. Immature monotonous greywacke sequences from the Lausitz (Lausitz Block) and Leipzig groups (North Saxon Anticline), as well as from the ea...

Orthosuchus stormbergi was a small‐bodied crocodyliform, representative of a diverse assemblage of Early Jurassic, early branching crocodylomorph taxa from the upper Elliot Formation of South Africa. The life history of these early branching taxa remains poorly understood, with only sparse investigations into their osteohistology, yet species like...

Climate changes are known to have been a key regulator of the biodiversity in Earth's history. However, the dry‐humid degrees and alternating patterns throughout the Phanerozoic remain largely unconstrained. In this study, we report high contents (2.4 ± 3.8 mg N kg⁻¹) and ¹⁷O anomalies (11.0 ± 7.4‰) of nitrate (NO3⁻) in the early Cambrian black sha...

Famous for its distinctive Komodo dragons (Varanus Komodoensis) and features home to underwater ecosystems, the Komodo National Park (KNP) has become a prominent and favorite destination of visitors locally and globally in recent years. Situated in Labuan Bajo, East Nusa Tenggara Province, Indonesia, KNP has three prime islands: Rinca, Komodo, and...

Zircon U-Pb dating, rock geochemistry, Sr-Nd-Pb, and zircon Hf isotope analyses were conducted on the ultrabasic and basic rocks of ophiolites in the Sabah area (Borneo, SE Asia). The zircon U-Pb ages of ultrabasic and basic rocks range from 248 to 244 Ma, indicating that the ophiolites already existed in the early Triassic. The rare earth elements...

The Pliensbachian–Toarcian succession of North Yorkshire provides a global reference for the interval incorporating the Toarcian Oceanic Anoxic Event (T-OAE, ∼183 Ma). Major and trace element, carbon stable-isotope (δ¹³Corg) and total organic carbon (TOC) data for the Dove’s Nest core, drilled close to the classic outcrop sections of the Yorkshire...