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Terminal Ediacaran–late early Cambrian deposition, faunas and passive margin evolution of the north Indian margin are recorded in the Nigali Dhar syncline succession. Restudy of the upper Tal Group (upper lower Cambrian Koti Dhaman Formation, KDF) ichnofauna from the Khud-Drabil section reduces it to 18 confidently named forms. The lower KDF (Lower Quartzite Member) Cruziana-Rusophycus assemblage is in subtidal (not intertidal) sandsheet facies. The overlying black Shale Member (SM) records trans-East Gondwanan deepening, not intertidal facies, in the Palaeolenus Zone. The SM, with low diversity Planolites-Palaeophycus assemblage, is overlain by subtidal (not intertidal) sandsheet facies of the middle KDF (Arkosic Sandstone Member, ASM) with shallow burrowers and furrowers (Gordia marina assemblage, new; Cruziana ichnofacies). KDF faunas with Cruziana and Rusophycus are similar to coeval, shallow marine associations elsewhere in Gondwana and NW Laurentia. Interpretation of a second KDF section 20 km from Khud-Drabil has confused an understanding of Lesser Himalaya geologic evolution as it claims Ordovician Cruziana species in the ASM and an angular SM–ASM unconformity caused by the Cambrian–Ordovician boundary Kurgiakh orogeny. However, upper lower Cambrian microfaunas occur in and above the ASM, while the angular SM–ASM unconformity is consistent with submarine sliding. KDF-type ichnofaunas do not show a tropical location of Avalonia, which has the distinctive lithofacies and biotas of a high-latitude continent unrelated to Gondwana. [ABSTRACT FROM AUTHOR]

This paper analyzes a letter sent by the South African paleobotanist Edna Plumstead in 1982 to the US philosopher of science Henry Frankel, in answer to his questions about her involvement in the early debates on the concept of continental drift. Her response gave a biographical account of her life and explained in what context she first became acquainted with the themes that would become her life's work, and the scientific network of people who influenced her along the way. Beginning with her undergraduate years in the 1920s, Plumstead was aware that continental drift was being discussed in scientific circles in South Africa, earlier than in the northern hemisphere. This was followed by her more direct involvement in paleontological studies on fossils of the seed-plant Glossopteris, her important description of Glossopteris reproductive organs in direct attachment to the leaves, and how the distribution of these fossils contributed to the concept of Gondwanaland and the continental drift theory. These contributions, although extremely relevant to science, were mostly ignored in the Global North. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibetan Plateau and its surrounding areas have a long and complex tectonic evolutionary history. Cratons and blocks, such as northern India, Lhasa, Qiangtang, Qaidam and Central Qilian, and their in-between orogenic belts constitute the main part of the Qinghai-Tibetan Plateau. During the Cambrian Period, most of these cratons and blocks were on the northwestern periphery of Gondwana, and were associated with the surrounding blocks, e.g. Arabian, Central Iran, Afghanistan, Tarim, Alxa, North China, South China and Sibumasu through the Proto-Tethys Ocean. The Cambrian stratigraphic sequences on these stable blocks are composed of mixed siliciclastic and carbonate rocks deposited in the shallow-water marine environments, and contain the trilobite assemblages of shelf facies. The Cambrian stratigraphic sequences in the Qilian tectonic belts, however, are characterized by the intermediate-basic igneous rocks and silicates formed in the Proto-Tethys Ocean, and contain the trilobite assemblages of deep-water slope facies. Combining with previous data, field observations and newly discovered fossils through funding by the Second Tibetan Plateau Scientific Expedition and Research, the general characteristics of the Cambrian strata in different tectonic units of the Qinghai-Tibetan Plateau and its surrounding areas have been summarized in this paper. Furthermore, efforts have been made to subdivide and correlate the Cambrian strata across these areas by utilizing available biostratigraphic and geochronological data. As a result, a comprehensive litho- and biostratigraphy chart has been compiled. Finally, from the biogeographic perspective, this paper also provides a brief overview of the Cambrian paleogeographical reconstruction of the major tectonic blocks, and discusses the problems associated with the evolution of the Proto-Tethys tectonic belt. [ABSTRACT FROM AUTHOR]

The Paleogene is a crucial period when terrestrial and marine ecosystems recovered from major disruptions and gradually approached their modern states. In the Qinghai-Tibetan Plateau and its surrounding regions, the Paleogene also represents a significant phase of tectonic evolution in the Qinghai-Tibetan Plateau-Himalaya orogeny, reorganization of Asian climates, and evolution of biodiversity. Due to limitations in research conditions and understanding, there are still many controversies regarding stratigraphic divisions in the Qinghai-Tibetan Plateau and its surrounding regions In recent years, extensive studies on sedimentary petrology, magnetostratigraphy, and isotope dating have been conducted in the region. Numerous fossils have been discovered and reported, contributing to a more systematic understanding of biostratigraphy. These studies have laid a solid foundation for the comprehensive investigation of the stratigraphy, biotas and paleogeographic evolution of the Qinghai-Tibetan Plateau and its surrounding regions during the Paleogene. In this paper, we integrate recent research on fossils, isotopic dating, magnetostratigraphy, and geochemistry to refine the stratigraphic divisions and correlation framework of different tectonic units in the region, building upon previous studies. Since the Second Tibetan Plateau Scientific Expedition and Research, the knowledge of Paleogene floras has gradually expanded. This paper discusses the biostratigraphic significance of extinct and newly appeared taxa based on the latest dating results of these plant species. The new understanding of fossil species such as the "Eucalyptus" and Arecaceae establishes connections between the Paleogene flora of the Qinghai-Tibetan region and the biotas of Gondwana, specifically Oceania and South America. The evolutionary history of key taxa near the Yarlung Zangbo suture zone indicates that the collision between the Indian and Eurasian plates occurred approximately 65–54 Ma. Paleoelevation reconstructions, based on plant fossils, suggest that the Hengduan Mountain had already formed their current topographic pattern prior to the Early Oligocene. The warm and humid lowlands adjacent to the main suture zones in the Paleogene Qinghai-Tibetan Plateau served as the primary pathway for biota exchanges. The relatively low elevation of the Himalaya during the Paleogene did not effectively block the moisture from the Indian Ocean. [ABSTRACT FROM AUTHOR]

The East Kunlun Orogen on the northern margin of the Tethyan orogenic system records a history of Gondwana dispersal and Laurasian accretion. Uncertainties remain regarding the detailed histories of northern branches of the Paleo-Tethys Ocean in East Kunlun Orogen (Buqingshan Ocean). Based on a synthesis of sedimentary, structural, lithological, geochemical, and geochronological data from the East Kunlun Orogen and adjacent regions, this paper discusses the spreading and northward consumption of the Paleo-Tethys Ocean during Late Paleozoic–Early Mesozoic times. The main evolutionary stages are: (1) during Carboniferous to Middle Permian, the Paleo-Tethys Ocean (Buqingshan Ocean) was in an ocean spreading stage, as suggested by the occurrence of Carboniferous MORB-, and OIB-type oceanic units and Carboniferous to Middle Permian Passive continental margin deposits; (2) the Buqingshan Ocean subducted northward beneath the East Kunlun Terrane, leading to the development of a large continental magmatic arc (Burhan Budai arc) and forearc basin between ~270–240 Ma; (3) during the late Middle Triassic to early Late Triassic (ca. 240–230 Ma), the Qiangtang terrane collided with the East Kunlun–Qaidam terranes, leading to the final closure of the Buqingshan Ocean and occurrences of minor collision-type magmatism and potentially inception of the Bayan Har foreland basin; (4) finally, the East Kunlun Orogen evolved into a post-collisional stage and produced major magmatic flare-ups and polymetallic mineral deposits between Late Triassic to Early Jurassic (ca. 230–200 Ma), which is possibly related to asthenospheric mantle upwelling induced by delamination of thickened continental lithosphere and partial melting of the lower crust. In this paper, we propose that the Wilson cycle-like processes controlled the Late Paleozoic–Early Triassic tectonic evolution of East Kunlun, which provides significant implications for the evolution of the Paleo-Tethys Ocean. [ABSTRACT FROM AUTHOR]

The Prototethyan Ocean has been suggested as an Early Paleozoic Ocean developed at the Gondwana northern margin. However, its spatial pattern, subduction style and closure time in SW Yunnan and SE Asia still remain unknown. The Prototethyan evolution in SW Yunnan and SE Asia and its internal connection with the South China Kwangsian (Ordo-Silurian) intracontinental orogenesis are also poorly constrained. By summarizing and analyzing the Early Paleozoic geological records in the Sibumasu and Indochina blocks, the eastern South China and SW Japan, this paper proposes the existence of a giant Ordo-Silurian igneous belt along the Gondwana northern margin. A preliminary limitation has been obtained regarding the source nature and migration pattern of the igneous belt. Our data allow us to propose a model of the Early Paleozoic Andean-type active continental margin along the East Gondwana northern margin. This is the foundation to determine the southward subduction of the southern branch of the eastern Prototethyan Ocean underneath the Sibumasu and Indochina blocks along the Yunxian-Menghai (SW Yunnan)-Thailand Peninsula and the Tam Ky-Phouc Son suture in Central Vietnam, respectively, and the eastward linkage with the Early Paleozoic Osaka subduction zone in SW Japan across the peripheral Sanya area. These data synthetically indicate an easterly-diachronous and propagating Andean-type Cambrian (Furongian)-Silurian (Llandovery) orogenesis along the Gondwana northern margin from Nepal, NW India, South Tibet, Qiangtang to Central Vietnam across South Indochina and Sibumasu. This paper reconstructs the Early Paleozoic locations of the Sibumasu and Indochina fragments, as well as SW Japan and South China continent in the Gondwana northern margin, and proposes the far-field effect on the South China Kwangsian intra-continental orogenesis from the subduction of the Early Paleozoic Prototethyan southern branch. [ABSTRACT FROM AUTHOR]

By studying fossil bite traces, we can reconstruct the behaviour of extinct organisms and better understand past communities, environments, and ecosystems. In this paper, we analyse bite traces on a fragmented sauropod rib from the Upper Cretaceous of the Bauru Basin, southeastern Brazil. The fossil was collected in the Ibirá municipality, São Paulo State, in the strata of the São José do Rio Preto Formation (Santonian-?Maastrichtian). The analysed specimen displays nine tooth drag traces on its external surface, produced by six or seven biting events. The traces consist of shallow linear grooves, with tapered ends and a serrated or smooth edge morphology. They can be classified as Linichnus serratus, Linichnus bromleyi, and Knethichnus parallelum and were produced by an organism with ziphodont dentition, probably an Abelisauridae. This work adds to the knowledge of the Bauru Basin palaeoecology and palaeobiology and expands the record of Mordichnia of Gondwana. [ABSTRACT FROM AUTHOR]

This paper investigates the origin of ultra-deep dolostone and the factors influencing large-scale dolostone reservoirs, focusing on the Sinian Dengying Formation and the Cambrian Longwangmiao Formation in the Sichuan Basin. The study involves petrology, microscale X-ray diffraction, trace element analysis, and C-O-Sr-Mg isotope experiments to provide a detailed analysis. The research findings indicate that the Dengying and Longwangmiao formations comprise six types of matrix dolostone and four types of cement. The Dengying Formation, which developed under a sedimentary background of a restricted platform, contains special microbial and microcrystalline dolostones. The dolomite grains are small (<30 µm) and have a low order degree (Min=0.55), with large unit cell parameters and an extremely high Na content (Max=788 ppm). The 87Sr/86Sr value of the dolostone is consistent with contemporaneous seawater, while the δ13C and δ18O values are lower than those of the contemporaneous seawater. The δ26Mg value is small (Min=−2.31‰). Powder crystal, fine-crystalline, and calcite dolostones with coarser and more ordered crystals exhibit similar δ13C and 87Sr/86Sr values to microbial and microcrystalline dolostone. During the sedimentary period of the Dengying Formation, ancient marine conditions were favorable for microbial survival. Microorganisms induced the direct precipitation of primary dolomite in seawater, forming microbial and microcrystalline dolostones during the seawater diagenesis period. During the subsequent diagenesis period, dolostones underwent the effects of dissolution-recrystallization, structures, and hydrothermal fluids. This resulted in the formation of dolostone with coarser crystals, a higher degree of order, and various types of cement. The Longwangmiao Formation was developed in an inter-platform beach characterized by special particle dolostone. The particle dolostone has a large grain size (>30 µm), high order degree (Min=0.7), small unit cell parameters, high Na content (Max=432 ppm), and low Fe and Mn content. The δ26Mg and δ13C values are consistent with the contemporaneous seawater, while the δ18O and 87Sr/86Sr values are higher than those of the contemporaneous seawater. There is mutual coupling between multiple-period varying δ26Mg values and sedimentary cycles. The dolostone in the Longwangmiao Formation resulted from the metasomatism of limestone by evaporated seawater. The thickness and scale of the dolostone in the Longwangmiao Formation are controlled by the periodic changes in sea level. The period of dolostone development from the Sinian to the Cambrian coincides with the transition from Rodinia's breakup to Gondwana's convergence. These events have resulted in vastly different marine properties, microbial activities, and sedimentary climate backgrounds between the Sinian and the Cambrian. These differences may be the fundamental factors leading to the distinct origins of dolostone formed in the two periods. The distribution of sedimentary facies and deep tectonic activities in the Sichuan Basin from the Sinian to the Cambrian is influenced by the breakup and convergence of the supercontinent. This process plays a key role in determining the distribution, pore formation, preservation, and adjustment mechanisms of ultra-deep dolostone reservoirs. To effectively analyze the genesis and reservoir mechanisms of ultra-deep dolostone in other regions or layers, especially during the specific period of supercontinent breakup and convergence, it is crucial to consider the comprehensive characteristics of seawater properties, microbial activities, sedimentary environment, and fault systems driven by tectonic activities. This can help predict the distribution of high-quality and large-scale ultra-deep dolostone reservoirs. [ABSTRACT FROM AUTHOR]

Comprehensive U-Pb detrital zircon geochronology of Ediacaran sandstones from Oman indicates that they originated from Neoproterozoic basement with a peak magmatic age of ca. 850-780 Ma (Tonian), with lesser Paleoproterozoic and Ediacaran sources and renewed magmatic input starting at ca. 550 Ma. Comparison with detrital zircons from the Arabian-Nubian and NW Indian Shields supports an eastern Gondwana affinity for the Ediacaran succession of Oman. Tonian basement sediment sources are present in Oman. Sources for older Paleoproterozoic zircons (ca. 2500 and 1800 Ma) are not found in Oman but are known from the cratonic Indian Shield. The signal of the main magmatic events of the juvenile Arabian-Nubian Shield, peaking at ca. 640-620 Ma, is rare or absent in the Ediacaran rock succession of Oman. However, deformed Ediacaran clastic units with an Arabian-Nubian Shield affinity occur in western Oman. Influx of latest Ediacaran-early Cambrian zircons (550-525 Ma) is interpreted as due to final Cambrian Angudan/Malagasy orogeny-related magmatism. These results, together with new ages for volcano-sedimentary terranes in the subsurface of SW Oman and seismic observations, support the interpretation that the Ediacaran succession of Oman was deposited along the western, passive margin of the Greater Indian Shield, on the eastern (east and west in this paper refer to present-day coordinates) side of the Mozambique Ocean. Oman then collided with the Arabian-Nubian Shield in the early Cambrian, when the Angudan/Malagasy orogeny led to final consolidation of Gondwana. Our data support the inference that the youngest and final suture between the Indian and Arabian Shields lies in the subsurface of Oman along the early Cambrian western deformation front. [ABSTRACT FROM AUTHOR]

Sardinia (Italy) represents one of the most comprehensive cross-sections of the Variscan orogen. The metamorphic and structural complexity characterizing its axial zone still presents many unresolved issues in the current state of knowledge. The data presented from the structural study of the entire axial zone of this area have allowed the authors to propose a subdivision into two new structural complexes. In particular, a younger complex is identified as the New Gneiss Complex, containing remnants of an older and higher-grade metamorphic complex defined as the Old Gneiss Complex. The structural and geometric relationships between the two complexes suggest the redefinition of the axial zone of Sardinia as part of the intracontinental East Variscan Shear Zone/medium-temperature Regional Mylonitic Complex. Comparable relationships are also highlighted in many other areas of the Variscan chain (e.g., Morocco, Corsica, Maures Massif, and Argentera Massif). Extending this new structural interpretation to other axial zones of the South European Variscan orogen could provide new hints for reconstructing the collision boundaries between Gondwana and Laurussia in the late Carboniferous to the early Permian periods. [ABSTRACT FROM AUTHOR]

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Among the vast swathes of Gondwanan sedimentary rocks in India, exposures of the Lower Permian Talchir Formation at Manendragarh in India are exceptional for their cold marine faunal assemblage and muddy conglomerates of possible glacial origin. They may represent a record of the late Palaeozoic glaciation that affected Gondwana in the Permo-Carboniferous. Although the fossil record is relatively well documented, the sedimentology of this area is not well understood. This paper intends to fill the gap in knowledge regarding palaeogeography and the palaeoenvironmental changes within the basin through space and time. We distinguish conglomerates that are formed by glacial and mass flow processes. The lateral variation in facies associations along a NNE-SSW transect in the study area identifies the depositional basin as an interior sea that formed when the sea spilled over a steep basement ridge during a transgression. The benthic organisms remained confined to the seaward basin margin where they only flourished in the initial stage of basin filling. Locally derived, bioclastic storm beds are limited to the seaward flank of the basin. Alternating phases of glaciation and interglaciation resulted in an interbedded succession of grey shales and interglacial density flow deposits. The channels that fed these density flows are preserved closest to the landward margin of the basin. Co-existence of glacial diamictites and interglacial density flow deposits highlights the climatic changes in this part of Gondwana during the Late Palaeozoic. [ABSTRACT FROM AUTHOR]

The formation ages and tectonic features of the Bulunkuole Complex (BKC) is critical for understanding the geological evolution of the western section of the West Kunlun Orogenic Belt (WKOB), and they are also critical for understanding the metallogenic background of the Taxkorgan Iron Belt. In this paper, we report new geochemical and in situ zircon U–Pb isotopes data for the most southwestern iron-bearing formation of the BKC. The petrography and sedimentation ages of the BKC reveal that the main part of the BKC was emplaced in the Early to Late Cambrian period as a giant accretionary wedge formed during the Proto-Tethys Ocean south-southwestward subduction. The high-pressure metamorphic rocks located at the margin of the Kangxiwa Fault should be further disintegrated from the Cambrian BKC to form a Triassic accretionary complex. Geochemical characteristics indicate that the metasedimentary rocks of the Cambrian BKC derived predominantly from the regional contemporary intermediate to felsic source rocks, and deposited in the fore-arc basin. Provenance studies further demonstrate that the detrital materials were mainly sourced from the Gondwana-affinity terranes, Mazar Terrane as well as the volcanic and magmatic rocks produced during the Tethys subduction. The metamorphism of the Cambrian BKC occurred at ca. 200 Ma in the western section of the WKOB. Proto-Tethys Ocean did not close until 230 Ma, possibly during the Early Mesozoic (200–180 Ma). [ABSTRACT FROM AUTHOR]

This paper focuses on one orogenic belt that formed during the Rinconada phase on the final stage of the Famatinian orogeny, between 445 and 410 Ma, which is well exposed at Sierra de Ramaditas and neighbouring ranges in western Argentina. The Ramaditas Complex is formed by metasedimentary and meta-ultrabasic rocks and amphibolites. This complex forms the upper nappe of a thrust stack resulting from westward thrusting. Deformation consists of an early high-temperature S1 foliation (stromatic migmatites), coeval with thrusting and metamorphism. Metamorphism attained peak P–T conditions of 6.0–6.9 kbar and 795–810 °C, at c. 440 Ma, i.e. coincident with the Rinconada orogenic phase. The lower unit and intermediate nappes crop out in the nearby sierras of Maz and Espinal and underwent low- to medium-grade Silurian metamorphism, respectively, together with the upper nappe, defining an inverted Barrovian-type metamorphism with T decreasing and P increasing downwards across the thrust stack (i.e. westward). We argue that the Rinconada orogenic phase developed near the continental margin of SW Gondwana, during a magmatic lull following accretion of the Precordillera terrane to the continental margin at c. 470 Ma. The active margin jumped to the west after accretion, and flat-slab subduction resumed in the early Silurian, provoking thrusting and imbrication of nappe stack under the still hot root (800–900 °C) of the older Famatinian magmatic arc. This 'hot-iron' process explains both the inverted Barrovian-type metamorphism and the missing overburden of 21 to 24 km implied by the P estimate. [ABSTRACT FROM AUTHOR]

Gonds are one of the largest and the earliest indigenous communities of India. The four Gond Kingdom - Graha Mandala, Deogarh, Kherla and Chanda formed the region known as "Gondwana". The Raj Gonds of Adilabad are the successors of the Chanda rulers. Their legacy of cultural heritage is carried out from Generation to Generation. All the tangible and intangible cultural heritage is on the verge of extinction due to the rapid urbanization, heavy influence and adaptation of popular culture and migration from native places to the cities. Intangible cultural heritage can be preserved in the form of documentation. The promotion of cultural practices can save the heritage by keeping the practices alive. Nagoba Jatara is one of the significant festivals still carried out and celebrated in traditional manners by the Raj Gonds. Documentation of such festivals and associated intangible cultural practices is a significant attempt to safeguard and preserve living practices of the Gondi Culture. The paper presents the case study of the Keslapur Nagoba Jatara. The methods used for data collection are field visits, ethnographic interviews, focused group interviews, participant observation and audio-visual documentation of the festival. This paper attempts to understand, analyze, and discuss the Gonds' indigenous cultural practices performed at Nagoba Jatara Festival, belief systems associated with various cultural and ceremonial ritualistic practices and the importance of documentation to preserve the intangible cultural heritage practices. [ABSTRACT FROM AUTHOR]

Porphyry copper ore is a vital strategic mineral resource. It is often associated with significant hydrothermal alteration, which alters the original mineralogical properties of the rock. Extracting alteration information from remote sensing data is crucial for porphyry copper exploration. However, the current method of extracting hydrothermal alteration information from ASTER remote sensing data does not consider the influence of disturbing factors, such as topography, and ignores the weak report of surface minerals, which has significant limitations. Therefore, this paper selects the Gondwana region of the East Tethys–Himalayan tectonic domain as the study area, combines waveform calculation with principal component analysis methods, proposes a spectral feature-enhanced principal component analysis (EPCA) method, and constructs a model to complete the automatic selection of principal components for each scene image. The results show that the etching information extracted by the EPCA method is significantly better than the traditional Crosta method in terms of etching area and spatial aggregation and discovers several prospective mineralization areas that have not yet been explored and exploited, such as Sakya and Xietongmen counties in Rikaze, providing theoretical support for subsequent mineralization exploration and large-scale mineral extraction. Meanwhile, obtaining the alteration information of the whole area can help to understand the distribution of mineralizing elements from a macroscopic perspective in the future, which is of great scientific significance in order to deeply analyze the formation process of metal deposits in mineralizing areas and improve the theory of porphyry mineralization. [ABSTRACT FROM AUTHOR]

This paper presents new structural, anisotropy of magnetic susceptibility (AMS), and petrological data in tandem with existing geochronological data to determine a polyphase Variscan tectonometamorphic event in the southwestern Moldanubian Zone of the Bohemian Massif. The high-grade metamorphic rocks of this Zone underwent the successive tectonometamorphic evolution (from ca. 360 to 310 Ma) that portrays three main geodynamic episodes: (a) The collisional to exhumation episode (ca. 360–335 Ma) recorded by the relict, steeply dipping, and ~ N(NNE) to S(SSW) striking foliation planes (S1) developed at temperatures of 720–754 °C and pressures of ca. 790 MPa (M1) and superimposed flat-lying foliation planes (S2) under temperatures of 674 ± 27 °C and pressures of 680 ± 110 MPa (M2). (b) The late-orogenic ~ N–S oriented shortening (ca. 335–325 Ma) controlled by convergence of a crustal segment derived from the Gondwana continent (newly named as the "Salzburgia Block) and the mostly consolidated Bohemian Massif. These collisional processes resulted in superimposition of the foliation planes (S3) dipping steeply to moderately to the ~ N to ~ NNE(NE), re-heating and metamorphic overprint at temperatures of 770–830 °C and pressures of 450–530 MPa (M3) and syn-tectonic emplacement of the numerous late-orogenic granitoids. (c) Subsequently, the switch in the paleostress regime from ~ N–S shortening to that of late-orogenic ~ ENE–WSW extension (ca. 325–310 Ma) led to the activation of regional right-lateral transtension and exhumation of the deep-seated rocks. Associated re-equilibration proceeded under temperatures of 662–701 °C and pressures of 362–437 MPa (M4 event). In the latter stages of this episode, the synchronous reactivation of the regional ~ NW–SE striking right-lateral shear zones (Pfahl and Danube) and the almost perpendicular ~ NNE(NE)–SSW(SW) striking left-lateral shear zones took place. [ABSTRACT FROM AUTHOR]

Deserts are stressful environments where the living beings must acquire different strategies to survive due to the water stress conditions. From the late Albian to the early Cenomanian, the northern and eastern parts of Iberia were the location of the desert system represented by deposits assigned to the Utrillas Group, which bear abundant amber with numerous bioinclusions, including diverse arthropods and vertebrate remains. In the Maestrazgo Basin (E Spain), the late Albian to early Cenomanian sedimentary succession represents the most distal part of the desert system (fore-erg) that was characterised by an alternation of aeolian and shallow marine sedimentary environments in the proximity of the Western Tethys palaeo-coast, with rare to frequent dinoflagellate cysts. The terrestrial ecosystems from this area were biodiverse, and comprised plant communities whose fossils are associated with sedimentological indicators of aridity. The palynoflora dominated by wind-transported conifer pollen is interpreted to reflect various types of xerophytic woodlands from the hinterlands and the coastal settings. Therefore, fern and angiosperm communities abundantly grew in wet interdunes and coastal wetlands (temporary to semi-permanent freshwater/salt marshes and water bodies). In addition, the occurrence of low-diversity megafloral assemblages reflects the existence of coastal salt-influenced settings. The palaeobotanical study carried out in this paper which is an integrative work on palynology and palaeobotany, does not only allow the reconstruction of the vegetation that developed in the mid-Cretaceous fore-erg from the eastern Iberia, in addition, provides new biostratigraphic and palaeogeographic data considering the context of angiosperm radiation as well as the biota inferred in the amber-bearing outcrops of San Just, Arroyo de la Pascueta and La Hoya (within Cortes de Arenoso succesion). Importantly, the studied assemblages include Afropollis, Dichastopollenites, Cretacaeiporites together with pollen produced by Ephedraceae (known for its tolerance to arid conditions). The presence of these pollen grains, typical for northern Gondwana, associates the Iberian ecosystems with those characterising the mentioned region. [ABSTRACT FROM AUTHOR]

The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed, diverse in lithotypes and rich in fossils. It records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern hemisphere. Thus, it is of great significance for explaining the global paleogeographic evolution, tectonic activities and biodiversity changes during this critical period. The blocks on both sides of the southern Tienshan suture zone and the Longmu Co-Shuanghu-Changning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions, showing important tectonic paleogeographic partitioning significance. The two suture zones represent the main branches of the Paleo-Asian Ocean and the Paleo-Tethys Ocean, respectively, and on this basis the Devonian System can be subdivided into three types: the Tienshan type, the Tethys type and the Gondwana type. Based on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas, this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction, providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of Gondwana. The results indicate that the North Qiangtang, South Qiangtang, Simao, Baoshan and Tengchong terranes, as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block, while the Lhasa Terrane has affinities with the Australian Block, and may be located between the South China and Australian blocks. In the Emsian (Early Devonian), the South China Block separated from the northern margin of Gondwana, a process that was accompanied by the opening of the Jinshajiang-Ailaoshan Ocean. In the Middle Devonian, the mid-oceanic ridge of the Paleo-Tethys Ocean expanded rapidly, corresponding with a global sea-level rise, the widespread development of carbonate platforms and nadir values of Devonian seawater strontium isotopes. By the Late Devonian, the Paleo-Tethys Ocean had reached a considerable size, leading to abundant occurrences of Upper Devonian radiolarian cherts in the Paleo-Tethys suture zones. [ABSTRACT FROM AUTHOR]

During the Permian-Triassic transition, dramatic environmental changes occurred, including the segmentation of Pangaea and the beginning of the Alpine orogenic cycle with widespread magmatism and tectonic activity. The Permian-Triassic succession deposited in the northern (palaeo-) Gondwana is now exposed in the inner Northern Apennines where it crops out discontinuously in the Middle Tuscan Ridge, a NS-oriented morphotectonic feature mainly formed by blue-schist and green-schist facies metamorphic rocks. In this paper, we describe a previously unreported late Palaeozoic succession exposed in the central part of the Middle Tuscan Ridge: the Montagnola Senese Ridge. This succession provides information concerning the enigmatic late Palaeozoic units exposed in southern Tuscany, and permits the age constraint of continentalization at the Permian-Triassic boundary with associated magmatism. Specifically, by integrating stratigraphic, structural, and petrographic data, we describe a siliciclastic, volcanoclastic-to-carbonate succession which recorded the transition from marine sedimentation to the typical continental, red-beds of the Verrucano tectofacies. Additionally, deformational features, metamorphism and age of the succession are discussed in terms of its tectono-sedimentary evolution and implications for the Palaeozoic-Triassic setting of the central Pangaea sector currently exposed in southern Tuscany. The results allow us to recognize a middle-late Permian pre-Verrucano succession, and to date the transition to continental facies as latest Permian. The microflora permits correlation of the pre-Verrucano succession to the late Palaeozoic units of the inner Northern Apennines, and establishes the diachronous nature of the Verrucano tectofacies exposed in the inner Northern Apennines. Finally, the thermal maturity of the organic matter indicates a maximum temperature of 387 ± 30°C attained during metamorphism. [ABSTRACT FROM AUTHOR]

Simple Summary: Earwigs (Dermaptera) have their highest diversity in the tropical areas of the southern hemisphere, whereas the temperate regions of the northern hemisphere have relatively few species. This pattern has been considered a reflection of their origin in Gondwana, the supercontinent that grouped most of the land masses in today's southern hemisphere, including Antarctica, South America, Africa and Madagascar. An analysis of the distributions of the major evolutionary lineages of earwigs supports the role of the Gondwanan breakup in determining the current patterns of their diversity, as well the influence of the Indian collision with the Eurasian plate. The dispersal into the Eurasian plate was largely constrained by the Himalayan orogenesis and the presence of colder temperatures. This climatic barrier was probably the most important factor that largely hampered the colonization of North America from South America. The Dermaptera are an insect order exhibiting their highest diversity in the tropical areas of the southern hemisphere. This pattern has been considered a reflection of a Gondwanan origin. However, this hypothesis has not been tested through analytical methods. In this paper, the world distribution of earwigs was analysed by using the 'Cladistic Analysis of Distributions and Endemism' (CADE), a method which groups areas of endemism on the basis of shared distributions and phylogenetic relationships among taxa. In addition, clustering techniques were applied to depict biotic relationships based on similarity indices. Results of CADE support the idea that Gondwanan fragmentation exerted a crucial role in shaping the current distribution of the main clades of earwigs. However, the relationships between India with South East Asia suggested a biotic interchange occurred after the Indian collision with the Eurasian plate. The overall scenario emerging from cluster analyses revealed a strong influence of dispersal events. Overall, the distribution of earwig major clades indicates that their biogeographical history was mainly characterized by vicariance events (led by the break-up of Gondwana) followed by large scale dispersal processes constrained by the Himalayan orogenesis and the presence of colder temperatures, which have largely hampered the colonization of the northern hemisphere. [ABSTRACT FROM AUTHOR]

The article discusses the idea of fixed continents connected by land bridges within the field of paleogeography, espoused in the papers "Gondwana Land Bridges" by Charles Schuchert and "Isthmian Links" by Bailey Willis, both published in 1932. The papers opposed the theory of continental drift championed by scientist Alfred Wegener. The author notes that the research focused on the southern hemispheric continent of Gondwana and comments on Willis' ideas about the tectonic uplifts of oceanic isthmuses and continental areas. Other topics include bathymetric data, Permian climates, and the lack of discussion of a North Atlantic land bridge.

Cadomian (Ediacaran–Cambrian) magmatic rocks have been reported in the eastern (e.g. the Çatalca and İhsaniye plutons) and western (e.g. the Binkılıç and Safaalan plutons) parts of the Istranca (Strandja) Massif. This paper aims to investigate the tectonic setting and the magma evolution history of the Cadomian magmatic rocks using both new and previously existing geochemical and geochronological data. The meta-granitoid rocks with intermediate to felsic composition are the main magmatic activity in the region. They intrude into metamorphic basement rocks composed of gneiss, schist, amphibolite, calc-schist, and quartzites (the Tekedere group). These plutons show strong foliation and traces of the polyphase metamorphism. All plutons are peraluminous and slightly metaluminous, mostly calc-alkaline and high-K calc-alkaline, and plot into the volcanic arc granites (VAG) field on the tectono-magmatic discrimination diagrams. The zircon U–Pb crystallization ages of the plutons are between 525.3 ± 3.5 Ma and 548.7 ± 2.3 Ma. Initial εNd values vary from −0.02 to 1.86. Nd-TDM model ages range between 1.08 and 1.24 Ga and indicate that the primitive magmas were originated and/or assimilated by the remelting of Neoproterozoic juvenile crustal rocks. New geochemical and geochronological data suggest a magma generation within a subduction-related magmatic arc setting in response to the southward subduction of the Proto-Tethys Ocean during the Late Precambrian-Early Palaeozoic period in the Istranca Massif. [ABSTRACT FROM AUTHOR]

The Late Devonian witnessed landscape evolution, increased atmospheric O2 level, intense organic and volcanic activities and initial expansion of earliest wildfires. This paper is focused on petrographic and geochemical studies of Famennian inertinite-bearing marine shale facies in northern Kerman (central Iran), a Late Devonian key area in north of Gondwana.Our studies point to a wildfire activity. During the Famennian, the wildfire activity occurred in lowland vegetation (covered by lycopods) under warm and humid conditions. The moderately hot burning temperature (446.7°C to 487.9°C) of the fire and the type of the land vegetation suggest prevalence of a surface wildfire. Following the burning of the land plants, the ground became exposed to weathering that could result in erosion of the soil. Inputs of terrestrial organic matter, nutrients (particularly phosphate) and detrital materials into a nearshore marine environment were mainly controlled by proximity of the depositional environment to the terrestrial source, intense continental weathering of rocks and the soil in the land, wildfire and continental runoff during rainfall. Generally, preservation and enrichment of organic matter and formation of macerals were controlled by wildfire activity, transportation, oxidation, bacterial/fungal degradation and detrital input. [ABSTRACT FROM AUTHOR]

The Ediacaran to Early Cambrian plate tectonics was dominated by a full dispersal of the supercontinent Rodinia and the subsequent amalgamation of Gondwana. There is a consensus that the final assembly of Gondwana was not completed until the Early Cambrian. Prior to the final assembly, however, one major uncertainty remains on the quantitative paleogeography: the mainland of Gondwana was plausibly positioned at either a high or low latitude at a single time instant to meet the dual-latitude ('high-latitude' and 'low-latitude') options of Laurentia and the requirement of <600 Ma Iapetus Ocean opening between Amazonia and Laurentia. This uncertainty mainly arises from the equivocal selections on the ca. 590-560 Ma paleopoles from Laurentia and very few paleomagnetic data from Gondwana continents. In this paper, we expanded the dataset of high-quality paleomagnetic poles on the basis of Robert et al. (2017, 2018) and Wen et al. (2020), and confirmed an inertial interchange true polar wander (IITPW) event from ca. 590-580 to 560 Ma. We then provide a continuously kinematic reconstruction in the TPW-based ('absolute') framework and thus reconcile the two enigmatic paleogeographic models in this interval. The occurrence of IITPW in late Ediacaran has important implications for understanding the coevolution of Earth's system, and multidisciplinary investigations of the IITPW associated processes are needed in future work. [ABSTRACT FROM AUTHOR]

This paper reports new geochronological data on metagranitoids (U–Pb SIMS) and ophiolites (Sm–Nd) from the Khanka massif. New and published data define the Early Neoproterozoic Matveevka–Nakhimovka terrane with 935- and 915-Ma early suprasubduction magmatism, 850–880-Ma and 757-Ma withinplate and Pacific-type transform margin magmatism, as well as the Late Neoproterozoic–Early Cambrian Dvoryan and Tafuin terranes with 543, 520, 517, and 513-Ma suprasubduction magmatism. These two terranes are separated by a suture (Voznesenka and Spassk terranes) formed by Ediacaran–Cambrian shelf deposits and a Cambrian accretionary wedge with ophiolites older than 514 Ma. The greater part of the Khanka massif formed in the late Cambrian, with the Kordonka island-arc terrane accreted at the end of the Silurian. The Sergeevka terrane of the Ordovician island arc joined it through the Early Cretaceous strike-slip movements. Heterogeneous structures of the main part of the Khanka massif can be traced to the north based on the analogous stages of magmatism and metamorphism, where the Jiamusi massif (including the East Bureya terrane) is an Early Neoproterozoic block and the eastern Songnen massif (including the West Bureya terrane) is a Late Neoproterozoic–Cambrian block. These blocks are separated by the Spassk–Wuxingzhen–Melgin suture formed by their collision in the Late Cambrian. The Bureya–Songnen–Jiamusi–Khanka superterrane formed as a part of the Gondwana supercontinent approximately 500 Ma ago through orogeny and accretion of the Rodinia supercontinent fragments. [ABSTRACT FROM AUTHOR]

The Western Carpathians and Himalayas belong to the same global Alpidic orogenic system, which is the result of Euroasian plate collision with the continental fragments of Gondwana after closing of the Tethys ocean. Having the field experiences from both distant mountain ranges of the same orogenic system and applying the principles of comparative tectonics, they were evaluated and compared in the paper. Generaly, they have the same collisional structural-tectonic style, but there are as well many peculiarities and differences resulting from the specific conditions of collision in the Western Carpathian and Himalayan areas. The Western Carpathians structure is a result of gradual alternation of Variscan (Hercynian; Paleozoic), Paleo-Alpine (Mesozoic) and Neo-Alpine (Cenozoic) convergent and divergent plate tectonic processes, while the Himalayas represents purely Neo-Alpine Cenozoic structure evolved during the continual long lasting and rapid plate convergence. Despite the geosutures from the earlier orogenic evolutions are known in the parallel north-located zone, too. As the most important factors, influencing character of collision, seems to be the geometry of converging plate margins and the rate of the ocean floor spreading/subduction, driving the orogenesis. Paper gives a brief overview of tectonic architecture and evolution of both mountain ranges and compares their common features and contrasts. [ABSTRACT FROM AUTHOR]

This paper proposes an algorithm to detect coal fires using time-series Land Surface Temperature (LST) maps generated from data acquired by a wide-swath Visible Infrared Imaging Radiometer Suite (VIIRS) satellite sensor. VIIRS provides remotely sensed thermal images daily during daytime and nighttime. The proposed algorithm primarily uses the trend component extracted at pixel level from time-series LST maps by using the Seasonal Trend decomposition based on Loess (STL) model. The proposed algorithm is suitable for detecting coal fires at the regional scale. The obtained results were validated with coal fire observations collected during a field survey. [ABSTRACT FROM AUTHOR]

Understanding of the geodynamic evolution of the Tethyan realm cannot be complete without paleogeographical reconstructions of the North Qiangtang Block (NQB) that occupies a central position in Tibet. However, the reliability of such a reconstruction for the Paleozoic still requires substantial improvement. In this paper, we present paleomagnetic results obtained from the Middle Permian limestones and Upper Permian volcanic rocks in the Tanggula area, aiming to provide precise constraints on the NQB kinematics during the geodynamic evolution of the Tethys realm. Combined with other available paleomagnetic data from the NQB, our results suggest that the block was stably located at ~24°S for a long time before the Middle Permian, started to drift rapidly northward in the Middle Permian, and reached ~8.4°S in the Late Permian. The NQB continued drifting rapidly northward during the Triassic until merging with the southern margin of Eurasia in the Late Triassic. We reviewed new and available paleomagnetic and geological data and proposed a revised model for the tectonic evolution of the eastern Tethys realm. The NQB likely belonged to a ribbon-like separate continental archipelago in the middle of the Paleo-Tethys Ocean during the early--late Paleozoic. The Cimmerian continent, including the South Qiangtang Block (SQB), rifted away from the northern margin of Gondwana and drifted northward to ~22°S in the Middle Permian. The continent approached or partially collided with the NQB, resulting in the rapid northward movement of the NQB and the formation of the Longmuco--Shuanghu suture between the NQB and SQB. [ABSTRACT FROM AUTHOR]

• A diverse jawed polychaete assemblage has been found in Katian/Hirnantian of Prague Basin. • Ancyrochitina merga and Tanuchitina elongata biozones are confirmed. • Scolecodonts confirm closer connection of Gondwana to Laurentia than to Baltica. Jawed polychaetes evolved and diversified extensively during the Ordovician. However, Ordovician polychaete jaws (scolecodonts) have remained poorly documented for many regions. This applies for the Prague Basin of peri-Gondwana, from where the previous study on Late Ordovician scolecodonts was published more than 70 years ago, with just two species preliminarily identified. The aim of the present paper was to fill this research gap and to study organic-walled microfossils from the boundary interval of the Králův Dvůr and Kosov formations (uppermost Katian and lowermost Hirnantian) at the Levín locality. As a result, a diverse assemblage of scolecodonts and chitinozoans was discovered. Chitinozoans are represented by at least 24 species from 15 genera, i.e., a relatively diverse assemblage whose species composition points toward the Ancyrochitina merga and Tanuchitina elongata biozones. The recovered jawed polychaete fauna contains at least 19 species from 14 genera. Taxa with labidognath and prionognath type maxillary apparatuses predominate in samples, whereas placognath and ctenognath taxa are relatively rare. A similar pattern is typical for the Laurentian samples but contrasts with the Baltic polychaete faunas. Polychaetaspids dominate in the Levín assemblage, followed by other families such as ramphoprionids, paulinitids, and atraktoprionids. The studied interval in the Levín section is represented by a succession of thin-bedded silty shales with diamictite beds, practically devoid of shelly fossils and with a variable degree of bioturbation. The deposits are interpreted as distal turbidites and debrites, reflecting sea-level changes driven by the growth and retreat of glacial ice and possibly also local tectonics. Reduced diversity and abundance of scolecodonts was recorded in the uppermost part of the Králův Dvůr Formation, which correlates with less bioturbation and finer silt fraction. The reported discovery shows wide geographical distribution and diversity of jawed polychaetes before and during the Hirnantian glaciation and mass extinction. [ABSTRACT FROM AUTHOR]

The igneous rocks of Cerro Cacheuta are considered a typical expression of the Permian-Triassic magmatism within the Andes Precordillera of Mendoza, Argentina. In particular, the southwestern margin of this hilltop is characterised by intermediate volcanic and felsic intrusives from the Choiyoi Group, one of the most extensive volcano-sedimentary suites of southern South America. The Choiyoi magmatism is widely associated with dramatic tectonic and environmental changes in the Gondwana supercontinent. Therefore, a better characterisation of the igneous facies of Cerro Cacheuta is critical to understand the evolution of Gondwana and recognise the multiple events that occurred towards the end of the Permian. This paper presents new data about the mineralogy, petrography, and geochemistry of the plutonic and volcanic units of Cerro Cacheuta, which enables authors to draw additional conclusions about the genesis and evolution of the magmatism in the region. Microscope observations indicate that the volcanic rocks are largely consistent with intermediate facies dominated by a porphyry texture with plagioclase and sanidine phenocrystals within a trachytic groundmass. Coetaneous breccias of possible hydrothermal origin and geodes with cryptocrystalline silica, limonite, and quartz are also recognised in outcrops. Geochemical analysis suggests that the lavas would likely correspond to andesites from a calc-alkaline magmatic arc. Furthermore, trace elements show enrichment in LREE/HREE, a slight negative anomaly in Eu, and concentration ratios compatible with crustal extension during the initial stages of the Choiyoi Group. Based on their chemical similarities, the monzonites of the Boca del Río Pluton would correlate with the lower section of the Choiyoi Group, of Permian age. In contrast, granites of the Cacheuta Pluton show a signature typically recognised in units from the Triassic and, therefore, would be comparable to the upper member of the Choiyoi Group. [ABSTRACT FROM AUTHOR]

The Tethyan evolution depicts the continuous process of landmasses separating from the Gondwana continent in the south, drifting northwards, and subsequently colliding with the continents in the north over the past 500 million years. In this process, the Tethyan oceans that formed between the landmass and the southern or northern continents underwent growth, evolution, and eventual closure with the early Cenozoic India-Eurasia collision. However, the Tethyan lithosphere did not disappear but rather continued to evolve after entering into the deep Earth. The current position, morphology, and volume of the subducted Tethyan oceanic slabs in the deep mantle record the latest moment of this continuous evolution, providing critical constraints for Tethyan studies. This paper summarizes and analyzes the results of global-scale whole-mantle seismic tomography in the past nearly two decades, revealing a northwest-southeast seismically high-velocity anomaly, which is linearly distributed at depths of 1000–2000 km beneath the Tethyan realm and referred to as the Tethyan anomaly. By searching for an optimal linear combination of previous global seismic tomographic models to best match the known subducted slabs in the upper mantle, we observe that the Tethyan anomaly extends approximately 8700 km in length and 2600 km in width, exhibiting a parallel structure with northern and southern branches. Combining geological records of oceanic subduction initiation and previous geodynamic studies, this study suggests that the main body of the Tethyan anomaly represents the remnants of the subducted Neo-Tethyan oceanic slabs, which subducted from the Late Jurassic to the early Cenozoic. The northern branch consists of subducted slabs from the Neo-Tethys beneath the southern margin of Eurasia, while the southern branch likely reflects the intra-oceanic subducted slabs of Neo-Tethys during the Cretaceous. The western portion of the Tethyan anomaly may reflect remnants of Paleo-Tethys, while the eastern portion, towards India and the Bay of Bengal, shows signs of subduction towards the core-mantle boundary. Finally, this study discusses the future prospects of whole-mantle seismic tomographic studies focusing on the Tethyan realm. [ABSTRACT FROM AUTHOR]

The provenance of the upper Cambrian to Upper Ordovician sedimentary rocks of Tasmania and Waratah Bay in southern Victoria provides information about the complex and dynamic tectonic environment present during their deposition. This paper uses U–Pb detrital zircon data to constrain stratigraphic comparisons and tectonic reconstructions of these rock sequences. Multivariate statistics are used to investigate the similarity between the U–Pb ages and quantify the disparity among different samples from various locations. In western and central Tasmania, the Tyennan region supplied most detrital zircons during the late Cambrian and Early Ordovician. The overlying Middle Ordovician Pioneer Sandstone records a switch in provenance with zircons derived from the Mount Read Volcanics (MRV) mixed with zircons similar to those from continental-derived Paleozoic sedimentary rocks deposited throughout east Gondwana. The Middle to Upper Ordovician Gordon Group in western and central Tasmania lacks detrital zircons younger than 1.2 Ga, which indicates a return to a local provenance from Precambrian rocks. In southern Tasmania, the switch to zircons derived from the MRV and east Gondwana-like sources occurred earlier within the Cambrian Deadmans Bay Formation, which is dominated by the east Gondwana Paleozoic zircon age signature. In the East Tasmania Terrane, Ordovician sedimentary rocks from Lefroy have detrital zircon populations dominated by Neoproterozoic and earliest Paleozoic sources similar to the Ordovician sedimentary rocks in the Lachlan Orogen. In southern Victoria, the Bear Gully Chert from Waratah Bay exhibit both Tyennan and distal Gondwana detrital sources. The switching of detrital zircon sources in the west Tasmanian sedimentary sequences implies the docking of Tasmania with mainland Australia during the Cambrian Tyennan Orogeny. The arrival of the distal zircons into these basins occurred at different times in the different areas, reflecting a complex local topography and paleogeography. Paleozoic sedimentary rocks in Tasmanian exhibit multisource detrital U–Pb age signatures that change over time, implying tectonic activity during their deposition. Paleozoic sedimentary rocks in northeastern Tasmania show Gondwana-wide detrital signatures similar to Lachlan Orogen. The Ordovician Bear Gully Chert at Waratah Bay in southern Victoria shows mixed Tasmanian and distal Gondwana detrital populations. The change in detrital zircon signature in western Tasmania suggests that VanDieland docked with the Australian continent during the Cambrian Tyennan Orogeny. [ABSTRACT FROM AUTHOR]

Middle to Late Ordovician (late Darriwilian –early Katian) trilobites from trinucleid, raphiophorid and cyclopygid biofacies are for the first time documented from the West Balkhash and North Betpak‐Dala regions in south‐central Kazakhstan. Twenty taxa are described; six of them, that is, Miaopopsis sokyrensis sp. nov., Pricyclopyge keralensis sp. nov., Kongqiaoheia sarytumensis sp. nov., Shumardia karasaiensis sp. nov., Triarthrus akkermensis sp. nov. and Mynaralaspis perforata gen. et sp. nov. are new to science. Six taxa are reported in open nomenclature and two are not identified on a genus level. A new trinucleid Subfamily Nanshanaspinae is designated. Newly discovered faunas show strong links to contemporaneous faunas of Tarim and, to a lesser degree, to those of South China and the Australian sector of Gondwana. Based on results of cluster analysis (Dice similarity), trilobite associations of raphiophorid biofacies from the Chu‐Ili and Stepnyak terranes form a single first‐order cluster with little similarity to the trilobite associations characteristic of the nielid and illenid–cheirurid biofacies from the Stepnyak and Tarbagatai regions. Also, there is no distinct interaction between the pelagic Degamella–Pricyclopyge association and other trilobite faunas. The geographical distribution of raphiophorid and trinucleid trilobites described in this paper, including species of genera Malongullia?, Miaopopsis, Nanshanaspis and Kongqiaoheia, supports Ordovician palaeogeographical reconstructions showing the Kazakh terranes as part of a huge archipelago situated on both sides of the equator in proximity to the west coast of Gondwana and positioned a considerable distance from the Siberia continent and its associated terranes. [ABSTRACT FROM AUTHOR]

The expansion of ice masses across southern Africa during the Late Palaeozoic Ice Age has been known for 150 years, including the distribution of upland areas in controlling the configuration of glaciation. In Namibia, increasing attention has focussed on long and deep palaeovalley networks in the Kaokoland region in the north, but comparatively little work has been attempted in the topographically subdued plains of the south, in the Aranos and Karasburg basins. The desert terrain of the Aranos area exposes diamictites of the Dwyka Group discontinuously over about 300 km, extending further south to the Karasburg area at the Namibian‐South African border along the Orange River. Whilst examined at a stratigraphic level, the nature of the contact between the Dwyka glacial rocks and underlying lithologies has not been systematically investigated. This paper presents the results from fieldwork in austral winter 2019, in which a highly varying basal contact is described that records the processes of growth, flow and expansion of ice masses across this part of Gondwana. At the basin margins, subglacially produced unconformities exhibit classic glacially striated pavements on indurated bedrock. In comparison, the basal subglacial unconformity in the more basinward regions is characterised by soft‐sediment striated surfaces and deformation. In the Aranos Basin, soft‐sediment shear zones originated in the subglacial environment. This type of subglacial unconformity developed over well‐differentiated, unconsolidated, siliciclastic materials. Where ice advanced over more poorly sorted material or cannibalised pre‐existing diamictites, 'boulder‐pavements' recognised as single clast‐thick boulder‐dominated intervals formed. Importantly, these boulder‐pavements are enriched in clasts, which were facetted and striated in‐situ by overriding ice. By integrating measurements of striation orientations, fold vergence and palaeocurrent information, former ice flow pathways can potentially be reconstructed over a wide area. [ABSTRACT FROM AUTHOR]

Cadomian calc-alkaline I-type and within-plate A-type igneous rocks are widespread in the crust of Iran where they are ascribed to a convergent margin associated with the southward subduction of Prototethyan oceanic lithosphere beneath N Gondwana. These rocks are found as unmetamorphosed magmatic rocks and their metamorphic equivalents (mafic to felsic gneisses) could have been generated in both Cadomian arcs and associated rear-arcs. Nearly all these exposures also contain metamorphosed metasediments, whereas Cadomian igneous rocks of central Iran are associated with thick sequences of unmetamorphosed terrigenous rocks. In the Zagros Fold-Thrust belt of S Iran, salt diapirs contain abundant xenoliths of Cadomian igneous and sedimentary rocks in association with evaporites, dolomites, carbonates, and banded iron-salt deposits. This paper presents new zircon U-Pb and geochemical-isotopic data from igneous clasts in the Chah-Banu salt diapir in SE Zagros. Petrographic and geochemical data indicate two different types of rock clasts; calc-alkaline, I-type dacites-rhyolites, and arc-related to E-MORB-OIB-like gabbros, basalts, and dolerites. New zircon U-Pb ages show that dacites formed at 538.2 ± 2.2 Ma, whereas gabbros show ages of 539.0 ± 1.8 Ma. Zircons from dacites have negative εHf(t) values of – 1.1 to – 8.3. In contrast, zircons from gabbros have higher εHf(t) values of +4.5 to +8.5, indicating crystallization from mantle-derived juvenile magmas. Bulk rock Nd-Sr isotopic data (e.g. ɛNd(t) = +0.3 to +4.0 and 87Sr/86Sr(i) = 0.7059 to 0.70848) for gabbros, dolerites, and basalts confirm that these rocks originated from a mantle source similar to enriched parts of the subcontinental lithospheric mantle, whereas dacites and rhyolites (with εNd(t) = −3.4 to −4.1 and 87Sr/86Sr(i) = 0.70806 to 0.70907) show strong interaction with, and/or re-melting of older continental crust. We suggest that the bimodal calc-alkaline and E-MORB-OIB-like magmatic rocks in salt diapirs as well as associated evaporites and sedimentary rocks formed in a retro-arc rifted basin behind the Cadomian magmatic arc. [ABSTRACT FROM AUTHOR]

Late Neoproterozoic to Early Cambrian (Cadomian) magmatic rocks are abundant in Iran, but their occurrence in east-central Iran is voluminous. This paper reports, for the first time, on the Cadomian rocks of the eastern Iranian region known as Tapeh Tagh and deals with their geochemistry and uranium-lead (U-Pb) zircon ages. The Tapeh Tagh region contains masses of Cadomian meta-igneous rocks (including various types of granitic gneiss) and overlying meta-sedimentary rocks. The granitic gneisses show tectonic contact with metasedimentary rocks and their connection appears to have been obscured during the younger tectonic movements. The granitic gneisses show mylonitic texture with quartz ribbons and feldspar augen. Laser Ablation Inductively Coupled Plasma Mass Spectrometry U-Pb dating of zircon grains, separated from medium to coarse-grained gneissic rocks, consistently yielded near concordant to discordant pairs of 527 ± 5 and 522 ± 10 Ma. Geochemically, these rocks show a felsic composition with SiO2 content varying from 70.30 to 79.63 wt.%, a high content of FeO(t), alkalis, and incompatible trace elements (Zr, Nb), along with high ratios of Ga/Al and FeO(t)/MgO. They have fractionated rare earth element (REE) patterns with La/Yb = 9.1–24.7. Eu shows depletion with Eu/Eu*<1. The highly fractionated granites of the Tapeh Tagh are geochemically classified into the volcanic arc granites (VAG) and within plate granite.The granitic gneisses are geochemically and geochronologically similar to other Cadomian granites and gneisses in other parts of Iran as well as the Cadomian magmatic rocks from Turkey. These widely disseminated Cadomian basement rocks in Iran and Turkey are considered as fragments of Neoproterozoic to Early Cambrian continental arcs that formed the northern active margin of Gondwanaland. [ABSTRACT FROM AUTHOR]

Palynology is one of the most useful tools for constructing biostratigraphic charts in the late Paleozoic basins of South America, but the lack of radiometric ages often makes it difficult to establish the precise age of the biozones. This paper focuses on two points: (i) the description of new Argentinian palynological assemblages referred to the Lueckisporites/Weylandites (LW) Biozone and (ii) the application of a new isotopic age that enables more confident large-scale correlations with the neighboring Paraná Basin of Brazil. The palynofloras were recovered from the upper part of the De La Cuesta Formation that crops out in the retroarc basin of the Paganzo Basin, more specifically obtained from mudstones intercalated with limestones, cherts, and tuffs interpreted as being deposited in a shallow water body. The assemblages are characterized by an abundance of bi-taeniate pollen grains of the Lueckisporites complex and multitaeniate pollen grains such as Lunatisporites, Protohaploxypinus, Striatopodocarpidites, Tornopollenites, and Vittatina. Colpate pollen grains are also represented by Marsupipollenites and Pakhapites. A U-Pb CA-ID-TIMS age of 278.84 ± 0.22 Ma, obtained from a tuff level interstratified with the fossiliferous strata, allows the age of the LW Biozone in the Paganzo Basin to be constrained for the first time and the adjustment of the record Lueckisporites virkkiae in Gondwana. Moreover, this date enables precise correlations with other basins, such as the San Rafael Basin (Yacimiento Los Reyunos Formation) in Argentina and the Brazilian Paraná Basin (Iratí Formation). [ABSTRACT FROM AUTHOR]

Proterozoic to lower Palaeozoic metamorphic sequences are exposed in southern Mexico providing an important geological record for Rodinia and northwestern Gondwana reconstructions. The Sierra de Juárez Complex (SJC) is an enigmatic basement block in southern Mexico that recorded Jurassic dextral strike-slip mylonitic deformation, likely instigated by Pangea break-up and opening of the Gulf of Mexico. However, the origin and pre-Mesozoic evolution of this block are poorly constrained. In this paper, we present the result of fieldwork, LA-ICP-MS U-Pb zircon geochronology, and major and trace element geochemical analyses that allow us to define the following lithological units in the SJC: (1) an anorthositic-gabbroic metamorphic unit (Viguera Suite) with protolith ages of 979–976 Ma and a thermal disturbance event at ca. 920–880 Ma; (2) a MORB-like metagabbroic unit (San Agustín Orthogneiss) with a protolith age of 441.9 ± 3.6 Ma; (3) a metamorphic supracrustal sequence (Etla Unit) that includes amphibolites and pelitic schists with maximum depositional ages of 422–414 Ma and a detrital provenance sourced in Gondwanan-type terranes; and (4) metagranitic intrusions with a protolith age of 191.9 ± 1 Ma, suspected to be syntectonic with respect to the Jurassic mylonitic event. The Silurian-Devonian San Agustín Orthogneiss and Etla Unit constitute the roots of a formerly undocumented lower Palaeozoic terrane that, together with the Viguera Suite, underwent high-pressure amphibolite facies metamorphism between 398–391 Ma, likely related to contractional tectonics. Based on these data, the SJC is proposed as a Mesoproterozoic to middle Palaeozoic crustal block with a geologic evolution coupled to NW Gondwana and a potential correlation with the Grenville-aged and peri-Gondwanan-type terranes like those currently located in southeastern Mexico, Central America, and northwestern South America. [ABSTRACT FROM AUTHOR]

During the Early Ordovician Epoch, the Mediterranean brachiopod Province was extensive in the higher-latitude sectors of the globe in the Southern Hemisphere. The latter was much occupied by the massive continent of Gondwana, which stretched from north of the Equator S-wards to cover the South Pole. The Mediterranean Province can be separated into two groups: Group 1, the higher-latitude fauna dominated by large linguliform brachiopods; and Group 2, which is more diverse, particularly in orthides. The large linguliform brachiopod faunas are particularly well known in southern Europe (France, Spain and Bohemia) and North Africa, and the second group in Avalonia, Chile and Argentina. The province is different from, but merges with, more diverse contemporary faunas in the lower latitudes of Gondwana to its north, although the latter contrast with other lower-latitude faunal provinces in South China, Laurentia, Siberia and elsewhere. Since the Rheic Ocean between Avalonia and Gondwana was relatively narrow during the Early Ordovician Epoch, the Avalonian brachiopods were integral parts of the Mediterranean Province, but only until end of the Dapingian Age. This paper focuses on the earlier phases of the Mediterranean Province, although the province continued until near the end of the Ordovician Period. Intermediate-latitude Baltica and some other faunas are included in new principal components and other analyses in order to compare them with the Mediterranean Province faunas. Radiation was very significant for many brachiopod taxa during the period, with first appearances of the Plectambonitoidea (Taffiidae), several orthide families (Euorthisinidae, Tarfayidae and Anamalorthidae) and the earliest endopunctate orthide, the dalmanelloid Lipanorthis. [ABSTRACT FROM AUTHOR]

Ichnology is fundamental to understanding characteristics of paleoenvironments such as hydrodynamic energy, oxygenation, salinity and substrate consistency. The Itararé Group is a Mississippian-Cisuralian lithostratigraphic unit of the Paraná Basin, in which trace fossils have been increasingly employed in paleoenvironmental reconstructions during the Late Paleozoic Ice Age in western Gondwana. The upper unit of the Itararé Group, the Rio do Sul Formation, exhibits a diverse trace fossil assemblage preserved in fine-grained rhythmites deposited in glacially related aquatic environments. In these rhythmites, trackways and trails produced by terrestrial and aquatic organisms were previously described. In this paper we report a new trace fossil collected from a rhythmite quarry near Trombudo Central, Santa Catarina state, and discuss potential paleoenvironmental implications. The studied specimen consists of an arthropod jumping trackway which could indicate a subaerial paleoenvironmental setting corroborating previous ichnological studies. [ABSTRACT FROM AUTHOR]

Normal incidence seismic data provide the best images of the crust and lithosphere. When properly designed and continuous, these sections greatly contribute to understanding the geometry of orogens and, along with surface geology, unraveling their evolution. In this paper we present the most complete transect, to date, of the Iberian Massif, the westernmost exposure of the European Variscides. Despite the heterogeneity of the dataset, acquired during the last 30 years, the images resulting from reprocessing the data with a homogeneous workflow allow us to clearly define the crustal thickness and its internal architecture. The Iberian Massif crust, formed by the amalgamation of continental pieces belonging to Gondwana and Laurussia (Avalonian margin), is well structured in the upper and lower crust. A conspicuous mid-crustal discontinuity is clearly defined by the top of the reflective lower crust and by the asymptotic geometry of reflections that merge into it, suggesting that it has often acted as a detachment. The geometry and position of this discontinuity can give us insights into the evolution of the orogen (i.e., of the magnitude of compression and the effects and extent of later-Variscan gravitational collapse). Moreover, the limited thickness of the lower crust below, in central and northwestern Iberia, might have constrained the response of the Iberian microplate to Alpine shortening. Here, this discontinuity, featuring a Vp (P -wave velocity) increase, is observed as an orogen-scale boundary with characteristics compatible with those of the globally debated Conrad discontinuity. [ABSTRACT FROM AUTHOR]

The Givetian to Famennian (Middle-Upper Devonian) Bahram Formation deposits (Bondar and Shahzadeh Mohammad sections) in the Kerman region, Central Iran were sampled for conodonts. The conodonts were described, their distribution investigated, and the studied sections were correlated. In the previous conodont-based papers, the age of the Bahram Formation in the Kerman region was from the upper Givetian hermanni Zone to the middle Famennian Uppermost marginifera Zone (Middle to Late Devonian). However, the new results of this study show that the Bondar section spans from the middle Givetian ansatus Zone to the upper Famennian (middle part of the Middle expansa Zone = Bispathodus aculeatus aculeatus Zone) and the Shahzadeh Mohammad section spans from the middle Givetian ansatus Zone to the lower Famennian (Uppermost crepida = Palmatolepis glabra pectinata) Zone. In both of the studied sections, the Givetian/Frasnian boundary has been identified by the first occurrence of Ancyrodella rotundiloba pristina, but there is no obvious (sedimentological or biostratigraphic) evidence to define the Frasnian/Famennian boundary. [ABSTRACT FROM AUTHOR]

Post‐glacial Permian coal‐bearing sedimentary successions are traditionally interpreted as fluvially deposited within the Gondwanaland continental set‐up throughout the globe. Recent attempts to reinterpret such successions in terms of marine flooding events, mainly based on sedimentological and ichnological attributes, raised doubt on the existing palaeogeographic model of the Late Palaeozoic Gondwanaland. Reassessing these sedimentary successions using other proxies, like petrographic and geochemical properties, may provide more reliable clues to improve the present understanding. In this paper, petrographic and geochemical analysis of sandstones, sandstone–mudstone heteroliths, and mudstones of the early Permian Barakar Formation of Lower Gondwana Supergroup, Raniganj coal Basin, India, is presented to understand the provenance, palaeoweathering pattern and palaeodepositional conditions. Petrographically, the sandstones are arkosic to sub‐arkosic in nature, with abundant unstable components and heavy minerals. Clay minerals in the matrix and the mudstones are dominated by kaolinite, illite‐smectite with authigenic glauconite, indicating a marine diagenetic realm. Mineralogical assemblage attests to sedimentation in craton interior passive margin conditions. Geochemically, the lithounits show large variations in major element and trace element (including rare earth element) concentrations. Chemical index of alteration and A–CN–K ternary plot indicate moderate to strong chemical weathering, leading to deposition of compositionally immature sediments close to their source without much recycling. Ratios of major elements (e.g., MgO, K2O, Fe2O3, Al2O3, and SiO2) signify a continental–marine transitional depositional environment developed in a stable passive margin setting under gradually warming up climatic conditions. Trace element ratios manifest an estuarine depositional setting during Barakar sedimentation, comparable with modern major river mouth estuaries. Thus, this paper provides unequivocal evidence of significant marine influence during sedimentation in the Lower Gondwana basins in India, particularly during the Permian time, and signifies the importance of re‐examining the so called “continental fluvial” coal‐bearing deposits as considerably marine‐influenced. The interpretations provide important clues in understanding and reconstructing the Permian Lower Gondwana palaeogeography in eastern peninsular India. [ABSTRACT FROM AUTHOR]

Knowledge of the Late Paleozoic sedimentary history of the northern Gondwana shelf is advanced by new data from the Şort Dere section (Hakkari Basin). Early Carboniferous myalinid bivalves from the Middle East are reported here for the first time. The pre-Permian basement of the Hakkari Basin consists of a Lower Carboniferous sedimentary sequence including the Köprülü and Belek formations. The Köprülü Formation has yielded rich assemblages of vertebrates and invertebrates. Hitherto myalinid bivalves were unknown from this formation; this paper reports the discovery of small and poorly calcified myaliniform shells from two thin beds in the middle part of the Köprülü Formation of the Şort Dere section in the Zap Valley. The morphological characteristics of the specimens, especially the umbonal region with the numerous rounded wrinkles, suggest that it probably belongs to an undescribed species of Selenimyalina Newell, 1942. Based on this record, the state of the art of warm-water myalinid taxa in the Paleotethyan Realm is shortly discussed with a focus on the pteriomorph bivalve faunas within a global scenario for both paleobiogeography and patterns of Gondwana-Laurussia faunal exchange. The new occurrence is one of the most important pteriomorph bivalve records ever made in Southeast Turkey, helping to assist paleogeographic reconstructions of the Paleotethyan paleocontinents. [ABSTRACT FROM AUTHOR]

Aim: Lungfishes are one of the two surviving clades from the once diverse grade of lobe‐finned fishes leading to tetrapods. This classic living fossil lineage, which is the living sister to four‐limbed terrestrial vertebrates, appeared approximately 425 million years ago and rapidly diversified. However, the evolution of lungfishes after their initial radiation is poorly understood, and whether their present distribution tracks ancient geographical change is a classic problem in biogeography. Location: Global. Taxon: Lungfishes (Dipnoi). Methods: Here, we combine mitogenomic, nuclear gene and fossil data to reconstruct the timing of lungfish diversification a Bayesian tip‐dating approach to quantitatively test hypotheses of lungfish historical biogeography and divergence times. We sample all major living and extinct lungfish lineages, including three of the four species of African lungfishes (Protopterus spp.), the Australian lungfish Neoceratodus forsteri, the South American lungfish Lepidosiren paradoxa and 13 fossils representing extinct lineages from across the globe. Results: Our results demonstrate that the divergences of the three major living lungfish clades closely recapitulate the stepwise fragmentation of the Gondwana during the Mesozoic. All of our model‐based biogeographical reconstructions support a Gondwanan vicariance model for the origins of the present distribution of lungfish lineages. Conclusions: In turn, lungfishes provide an excellent example of how the integration of fossil data may drastically change support for historical biogeographical hypotheses previously discounted by molecular data and are one of the few living animal lineages that record incredibly ancient geographical changes in their phylogeny. [ABSTRACT FROM AUTHOR]

A complete pore characteristic of the Indian Gondwana shale is studied by combining laboratory experiments and numerical modeling. Mercury injection capillary pressure (MICP), nitrogen gas adsorption (N2GA) and scanning electron microscopy (SEM) are the primary laboratory methods used to evaluate the pore characteristics. The N2GA and MICP were coupled to estimate the pore size distribution (PSD) of Indian Gondwana shale for the first time. The estimated PSD of Gondwana shale varies between 0.5 nm to 100 µm and most of the pores of the samples fall in the micropore and mesopore category. The porosity of Gondwana shale, measured using MICP, varies from 1.13 to 8.01%. The SEM micrographs and hysteresis pattern of isotherms reveal the presence of cylindrical, ink-bottle and slit shape pores in the samples. The BET (Brunauer-Emmett-Teller) surface area of pore for Gondwana shale varies from 3.42 m2/g to 21.5 m2/g. The FHH (Frenkel-Halsey-Hill) fractal model suggests that the Gondwana shale exhibits two types of fractal dimensions with highly complex pore geometry. The adsorption capacity of Gondwana shale is affected by the clay content. This paper attempted a different interpretation approach using experimental data and concluded that Indian Gondwana shale has high gas storage capacity. [ABSTRACT FROM AUTHOR]

In the Balkans, the Serbo-Macedonian Unit (SMU), Serbia, is thrust bounded by the composite Tethyan Vardar Zone and the Carpatho-Balkanides. The SMU actually emerges from beneath the Neoalpine Miocene-Pliocene deposits. Both provenance and geodynamic position of the SMU are poorly known and still debated. This paper reviews the data hitherto published and includes some new field data interpretations. The SMU is composed of a Neoproterozoic-Cambrian high-grade (para- and ortho-) gneiss with peraluminous magmatic arc components (560-470 Ma). The SMU is in the contact with Neoproterozoic upper Ordovician-Carboniferous low-grade metasedimentary succession of an accretionary wedge assembly represented by the Supragetic basement. The SMU basement became folded, sheared and metamorphosed around 490-450 Ma. Paleomagnetic data point to high southern latitudes and a peri-Gondwanan position of the SMU at that time, which concurs with glaciomarine evidence recorded from the upper Ordovician sediments at the base of an accretionary wedge succession. Based on the published data and field survey in the Stalać region, we correlate the SMU with the pre-Mesozoic gneiss terrane exposed in the Strona-Ceneri zone of the Alps. This terrane, identified as the Cenerian orogen of the Alaskan subduction type, developed at an active margin of Gondwana during middle Ordovician times. The SMU basement, with augen and migmatitic gneisses and arc-related peraluminous magmatic bodies, developed at this margin as part of the Cenerian belt or its equivalent. Such an orogenic edifice proved transient and in the earliest Silurian the SMU fragments drifted away being bound for Baltica (amalgamated Moesian microplate and Danubian terrane) to which they became accreted in the Carboniferous and included in the southern European branch of the Variscan orogen (Marginal Dacides/Carpatho-Balkanides). Despite considerable Variscan and Alpine reworking, the pre-Variscan, Cenerian-type crustal assembly along with an inferred boundary between the magmatic arc and the accretionary wedge, accompanied by back-arc/forearc deposits, are still decipherable in the Western Balkan countries. [ABSTRACT FROM AUTHOR]

Many volcanoes are buried within Te Riu-a-Māui/Zealandia sedimentary basins. Based on a large collection of seismic reflection and drillhole data, this paper outlines the morphology, location and age of over 400 volcanoes buried and preserved in offshore New Zealand basins. We discuss the relationships of these volcanoes to the timing and locations of the main tectonic events that shaped Zealandia in the last 105 Myr. Late Cretaceous volcanism mainly formed large (>20 km3) composite cones and volcanic complexes that erupted along rift faults related to the break-up of Zealandia from south-eastern Gondwana. Cenozoic intraplate volcanic activity was widespread, typically forming clusters of scattered small-volume (<1 km3) craters and cones. In contrast, large Cenozoic volcanic complexes, composite cones and shield volcanoes erupted along linear arcs associated with subduction along the Pacific-Australian plate boundary. In detail, the presence of pre-existing structures and types of host rocks also influence the passage of magma in the shallow (<5 km) crust and the location of eruptive centres, regardless the tectonic setting of eruption. Insights from this work demonstrate the value of characterising volcanoes buried in sedimentary basins for improved understanding of the interplay between volcanism and plate tectonics in Zealandia and further afield. [ABSTRACT FROM AUTHOR]

In the supercontinent of Rodinia, Baltica occurred next to Amazonia, then the two drifted away when Rodinia broke up. By the end of the Neoproterozoic, Baltica became an independent continent. At that time, Timanide orogen developed at its modern northeastern margin. In most paleogeographical reconstructions, the opposite (SW, Tornquist) edge faced the Tornquist Ocean and remained just a passive margin till the arrival of the Gondwana-born East Avalonia in the late Ordovician. However, preliminary isotopic studies of detrital zircons from the Tornquist passive margin succession hinted that rock components of Gondwana derivation reached Baltica already in the early Cambrian. In this paper, we examine 18 drill-cores of Ediacaran-Cambrian and Ordovician siliciclastic rocks from the tectonostratigraphic units along the SW–NE transect from Upper Silesia (USB) via Małopolska (MB) and the Holy Cross Mts (HCM) to the East European Platform (EEP), SE Poland, in terms of the provenance data gained from the LA-ICP-MS and SHRIMP analyses of 32 zircon samples. Rocks from all the units revealed abundant Cadomian 0.7–0.55 Ga detrital zircons (15–50% of the total analyzed grains) and other grains that yielded peaks at 0.9–1.2, 1.4–1.6, 1.8–2.2, 2.7–3.0 Ga assignable to Baltica rather than Amazonia. Such age spectra in the USB, HCM and EEP prove the proximity of peripheral (peri-Gondwanan) fragments of the Cadomian orogen to Baltica. These fragments formed the Teissyere-Tornquist Terrane Assemblage (TTA) that obliquely docked and overrode the thinned southwestern edge of Baltica which earlier accumulated Neoproterozoic rift and passive margin deposits. Our data show that in the late Ediacaran-early Cambrian, parts of the Cadomian orogenic belt became accreted to Baltica. [ABSTRACT FROM AUTHOR]