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Mangalia area harbors in the western Black Sea a distinctive marine environment thriving under specific hydrochemical conditions, largely influenced by a significant number of sulphurous springs occurring in shallow marine waters. These springs led to the designation of the area as part of the Natura 2000 Marine Protected Area (MPA) network at European level (Underwater Sulphurous Springs from Mangalia - ROSAC0094), as unique hydro-geomorphological features in the region. In 2021 and 2023, two research cruises led by GeoEcoMar investigated underwater sulphurous springs primarily located offshore of Mangalia (Constant, a County, Romania). The study area, located between 17-29 meters water depth and 1.8-3 km offshore, encompasses two marine protected areas: the Underwater Sulphurous Springs from Mangalia (ROSAC0094) and Cape Aurora (ROSCI0281). The research combined geophysical and geochemical techniques and sediment sampling. Considering the susceptibility of these natural systems to human activities such as fishing and dredging, as well as the impact of ecological and climate changes, this paper offers significant insights contributing to the development of effective conservation and management strategies for these environments. The surveys were conducted for benthic habitats mapping, with the objective of improving our understanding of these ecosystems' distribution, composition and dynamics. As these sulphurous waters are rich inmethane, a powerful greenhouse gas, our results also contribute to the inventory of greenhouse gas sources. The results presented in this paper provide valuable new insights into this specific environment, contributing to the understanding of its complex functioning and evolution. [ABSTRACT FROM AUTHOR]

Reyna Bay, an artificial bay on the northern Romanian Black Sea coast near Constanța, underwent significant modifications between 2015 and 2016 to protect against erosion. Reinforced embankments and submerged spur dikes were installed to stabilize the shoreline, while newly added sand with a high shell fragment content can mitigate sediment loss. This study focuses on habitat mapping in Reyna Bay, covering an area of 400 m in width and extending up to a kilometre beyond the bay. Habitat mapping is crucial for understanding the distribution of marine habitats, especially in areas where coastal interventions alter natural processes. This research aims to provide a detailed habitat map of the bay using a combination of modern remote sensing techniques, including acoustic classification methods for seabed sediments. By integrating bathymetric, sedimentological, and biological data, the study not only assesses current seabed conditions but also contributes to European marine biodiversity efforts through data-sharing initiatives, such as the European Marine Data Portals and the EUNIS classification system. The primary objective of this study is to classify and map seabed habitats using advanced technologies such as multibeam and singlebeam echosounders, sidescan sonar, and sediment sampling. The collected data was validated through ground truthing and biological sampling, ensuring an accurate habitat classification. By studying the area both within and outside of the bay, this research reveals how recent coastal modifications have influenced sediment distribution and habitat structure. [ABSTRACT FROM AUTHOR]

Deep‐water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years. This study discusses the co‐evolution of volcanism and deep‐water gravity flow deposits at the southern margin of the Junggar Basin, based on petrology, geochronology and geochemical analyses. The results show that a massive collapse of unstable sediments from the slope was triggered by volcanism, resulting in the formation of slumping gravity flows. The occurrence of volcanic beds in the slump deposits confirm that synchronous volcanism likely affected sediment instability, triggering gravity flows. The Th/Yb, Ta/Yb and Th/Ta elemental ratios, U‐Pb ages of detrital zircons and paleocurrent directions indicate that the North Tianshan (NTS) island arc represents the provenance of the Qianxia Formation. Moreover, statistical data on the pyroclastic components in the gravity flow deposits reveal an intensity index of volcanism, indicating that volcanism is strongly related to gravity flow deposits, especially in terms of the type and distribution of the deposits. A model for volcanically‐triggered deep‐water gravity flow deposits is established, in order to provide a more in‐depth understanding of the co‐evolution of volcanism and gravity flow deposits within the depositional setting of the late Paleozoic NTS oceanic subduction margin in the Junggar Basin. [ABSTRACT FROM AUTHOR]

The end‐Triassic mass extinction is considered one of the "Big Five" extinction events in the Phanerozoic. However, whether the terrestrial ecosystem began to deteriorate or even collapse prior to the Triassic–Jurassic (Tr‐J) transition remains controversial. Compared with the documented data from the western Tethyan region, evidence from the eastern Tethyan realm is limited. We undertake a fitting analysis of the sedimentary system, floral community successions and major geological events of the Xujiahe Formation as reflected by the Qilixia Section, Xuanhan area, northeast Sichuan Basin, China. Our results reveal an oscillating fluvial‐lacustrine depositional system during the Late Triassic, with the dominant sedimentary processes mainly controlled by the Indosinian Movement. Beside the sedimentary influence on the Xujiahe Flora, climate changes played a more important role. Fluctuating conditions to cooler and dryer climates at this time promoted diversification of gymnosperms under an overall warm and humid climate setting in the Late Triassic in the Xuanhan area. Superimposed on this oscillating long‐term climate state, ecosystem destabilization occurred over 1 million years prior to the Tr–J interval in the Xuanhan study area, possibly in response to the intensified storm and wildfire activity and the following environmental changes. Although the Xujiahe Flora always recovered from the interruption of the tectonic movement, it ultimately collapsed under extreme climatic events and ecological pressures induced by the Late Triassic Central Atlantic Magmatic Province event. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the thermal maturity of Upper Badenian (Middle Miocene) petroleum source rocks of the Getic Depression, Romania, and to characterize the dispersed organic matter using organic petrography associated with Rock-Eval pyrolysis. A total of 33 core samples of Upper Badenian source rocks from the central–southern part of Getic Depression was studied. The results show that most samples with values of total organic carbon (TOC) < 1% wt.% have a limited potential of hydrocarbons (HC) generation, and 30% of samples with TOC < 1.82 wt.% and kerogen type III, presenting particularly gas generation potential. In three samples from the Bibești, Grădiște and Socu structures the kerogen type III-II was identified, indicating the capability of oil and gas generation. The Badenian source rocks are thermally immature, as few samples are in the pre-oil window, with values of vitrinite reflectance (VRo%) ranging between 0.41% and 0.55%, and the values of Tmax between 409 °C and 443 °C. Optical microscopy with reflected white light and fluorescence blue light was used for identification of terrigenous macerals (vitrinite, liptinite as, resinite, cutinite, sporinite, and inertinite) associated with marine liptinite macerals (telalginite and lamalginite) showing yellow and bright–yellow epifluorescence. [ABSTRACT FROM AUTHOR]

The sequence of Permian volcanic and volcaniclastic rocks (up to 2 km thick) in the Sirinia Basin (Svinița-Svinecea Mare sedimentary zone) of the Upper Danubian Units, South Carpathians, is considered to be the product of subaqueous volcanism passing into a subaerial volcanism and subsequent deposition by debris flow. The investigated volcano-sedimentary rocks are composed of a rhyolitic clastic framework embedded within a fine-grained matrix. The electron probe microanalyses of monazites in the rhyolite clasts and in the volcaniclastic matrix yielded a U-Th- total Pb mean age of 296±3.2 Ma. This result is the first to constrain the age of the volcanic activity event recorded in the volcaniclastic rocks of the Sirinia Basin. The monazite age also estimates the maximum depositional age of the volcano-sedimentary rocks as not older than early Permian (middle Asselian). [ABSTRACT FROM AUTHOR]

The Carboniferous Cucuiova Formation of the Sirinia Basin, Danubian Units, in Almăj Mountains, South Carpathians, yields a highly diverse yet rare compressive flora representing significant heritage values of the Iron Gates Natural Park. This flora includes pteridophytes (lycopsids, sphenopsids, filicopsids) and gymnosperms (pteridosperms and conifers), some of these representatives being important coal generators during the Late Carboniferous times. The facies features, distribution and paleofloral features of the Cucuiova Formation are discussed in the framework of the Sirinia Basin. The lycopsid Lepidophloios acerosus Lindley et Hutton 1831 is reported for the first time in Romania from the Cucuiova Formation in Dragosela Valley, in the central part of the Iron Gates Natural Park. [ABSTRACT FROM AUTHOR]

The Cucuiova Formation is a Pennsylvanian (late Carboniferous) coal-bearing unit in the intramontane Sirinia Basin, which was formed in the Danubian Units of the South Carpathians. The main coal seam in the Cucuiova Formation was worked at Baia Nouă (Nové Doly) and this locality has yielded a typical adpression coal flora. Previous studies have suggested that this flora was Moscovian (late Westphalian or even earliest Stephanian) in age. However, newly collected samples from Baia Nouă have included abundant Neuralethopteris, which clearly indicates a late Bashkirian (Langsettian) age. This suggests a possible link with the Svoge Basin in northern Bulgaria, which is another intramontane basin located on the Balkan Terrane with early Westphalian coal-bearing deposits. [ABSTRACT FROM AUTHOR]