Upper Jurassic and Lower Cretaceous limestones and dolostones serve as hydrocarbon reservoirs in the offshore area of NE Spain. Since similar dolomitized rocks crop out in the adjacent onshore Maestrat Basin in the SE Iberian Range, understanding the dolomitization and other diagenetic processes is key to assessing reservoir properties. The Maestrat Basin dolostones crop out as elongated, asymmetric bodies, ranging from tens of centimetres to kilometres in length and up to 150m thick, with a wedge-shaped geometry closely associated with fractures. These dolostones are calcium-rich with low concentrations of Mn, Sr, and Na, but variable Fe, indicating that the replacement of the host limestone was followed by dolomite cement precipitation. Fluid inclusion data suggestthat dolomitization took place at temperatures ranging between 70 and 120ºC. Such temperatures, together with the high 87Sr/86Sr ratio and fluid salinity (16 to 23% wt. NaCl equivalent), reveal that the dolomitization process took place in burial conditions, from fluids that were infiltrated and likely interacted with Triassic, Liassic, and basement rocks. Although the exact age of dolomitization is not fully constrained, it is thought to coincide with fault-related dolomitization events of the same type previously described in the Maestrat Basin, likely during the latest Early Cretaceous and/or during the Late Cretaceous, in relation to the post-rift basin stage. Geochemical differences between the depocenters and structural highs may reflect the controls of the Maestrat Basin basinarchitecture on the composition and distribution of fluids.

The Aptian–Albian transition in the Maestrat Basin (E Iberian Chain) encompasses two lithostratigraphic units: the Benassal and Escucha formations. In some sectors of the basin, such as the western Galve and Las Parras sub-basins, this stratigraphic interval recorded a progressive shift from widespread carbonate platform settings to coastal siliciclastic-influenced and coal-bearing environments. Due to the transitional nature of this interval, establishing a clear stratigraphic boundary between the upper part of the Benassal Formation and the lower part of the Escucha Formation is challenging. Additionally, there is no unanimous agreement on the age range of these formations. To shed light on the stratigraphic location of the boundary between the Aptian and the Albian, strontium-isotope analyses were carried out on thirteen low-Mg calcite oyster shells to derive numerical ages. In the Las Parras Sub-basin, the 87Sr/86Sr values obtained from the siliciclastic-influenced transitional deposits between the Benassal and Escucha formations, as well as from the lowermost part of the Escucha Formation, range from 0.707282±0.000002 to 0.707410±0.000002. These Sr-isotope ratios translate into numerical ages that constrain this stratigraphic interval to the early Albian. The oyster shells collected in the Galve Sub-basin exhibit a higher degree of diagenetic alteration. Nevertheless, the least altered specimens analysed from the lower part of the transitional facies between the Benassal and Escucha formations in this latter sub-basin yielded Sr-isotope ratios between 0.707197±0.000003 and 0.707256±0.000002. These values correspond to ages spanning from the latest Aptian to the earliest Albian. Accordingly, in most sectors of the western Maestrat Basin, the Aptian–Albian boundary is likely to be stratigraphically located at the lowermost part of the transitional facies between the Benassal and Escucha formations.

The magnetic fabrics (or anisotropy of magnetic susceptibility) are used in this work to decipher thrust kinematics in the Cantabrian Mountains (western Pyrenees). Most of the analyzed rocks (total of 51 sites) correspond to the Mesozoic rifting and post-rifting stages (Triassic, Jurassic and Cretaceous) rocks in the Asturian-Leonese region, whose alpine structure is controlled by south-verging, basement-involved thrusts. Paramagnetic minerals are scarce as shown by the thermomagnetic analyses, and maghemite/hematite predominates as carriers of the magnetic fabric. The rifting phase is recorded by a primary fabric that remained unaltered during the alpine contraction, whereas the magnetic fabric of the Albian and Upper Cretaceous rocks show a reorientation due to contraction, which is better recorded in the fine grained continental facies of the Utrillas Group than in the carbonatic rocks overlying them. In the contractional fabrics found, the magnetic lineation delineates the thrust front enhancing the changes of the local shortening direction along strike. This reinforces the hypothesis of a strong control of the thrust direction by inherited structures.

The study explores the Precambrian tectonic evolution and the growth of continental crust in the southern region of the North Odisha Singhbhum Craton (NOSC), delving into the potential petrogenetic processes and source characteristics. The Tikiba Granitic Complex (TGC) is in the contact area of the Eastern Ghat Mobile Belt (EGMB) and the NOSC. The present study involves the geochemical characteristics of TGC granitoids and their geochemical variations. Petrographically, the TGC is comprised of alkali feldspar granite, monzogranite to granodiorite. The major element geochemistry reveals calc-alkalic, ferroan to magnesian affinities, and a metaluminous, peraluminous and peralkaline character. It is enriched in LILE and HFSE like Yb, Sm, Zr and Y. The (La/Yb)N values range from 4.0–26.1 and exhibit distinct negative Eu anomalies (Eu/Eu*) (0.4-0.6). This granitic complex shows high ΣREE contents of 176-860ppm with variable enrichment in LREE. Both REE and other incompatible element compositions define an A-type affinity. Based on geochemical data, we conclude that these granitoids have probably derived from a predominant crustal source with variable mantle characteristics in a post-orogenic setting.

The Aptian shallow-water carbonate platform of the Benassal Formation in eastern Spain (Maestrat Basin) contains facies dominated by scleractinian corals. Corals and coral reefs are widely used as environmental archives; however, the effects of their complex diagenetic evolution are a major factor impacting reliable reconstructions of the environments. This study addresses the environmental signatures (i.e. relative sea-level changes) and burial conditions that controlled the various diagenetic minerals present in the Aptian coral facies. A multiproxy approach including petrographic and geochemical evaluation reveals the diagenetic pathways, fluid compositions and timing accounting for the syn- to post-depositional history of this ancient coral facies. Cc1, which shows low Fe and Mn content and high Na content, precipitated within the primary porosity, alongside the replacement of coral skeletons, in a mixing zone dominated by marine waters. Cement Cc2, characterized by its higher Fe and Mn content and low Na values, precipitated in the mixing zone dominated by meteoric waters related to a relative sea-level drop. Cement Cc3, distinguished by low Fe and Mn content and high Na content, reflects a subsequent phase of increased marine influence, likely associated with a relative sea-level rise. Silica and isolated rhombohedral dolomite crystals formed concurrently in this mixing zone. During intermediate burial, saddle dolomite and cement Cc4 precipitated from high-temperature formation brines. Finally, during uplift, meteoric fluids caused the calcitization of previously formed dolomite rhombohedra.

Late Carboniferous coal seams in the Zonguldak Basin (NW Türkiye) underwent several tectonic movements after the Late Permian; hence, these seams exhibit rank variations. This study presents initial insights into coal rank, mineralogical compositions, and hydrocarbon generation potential of Serpukhovian-Bashkirian coals within the Alacaağzı Formation from the south-easternmost part of the Basin. The examined seams are of bituminous C rank, and Tmax (442–445°C) and HI (221–288mg HC/g TOC) values indicate that they are at the set of oil generation. However, the low PI (0.01–0.02), BI (0.03–0.06), and QI (2.2–2.9) values and the possible presence of preserved cytoplasm spore-filling within the sporinite grains may indicate that the studied coals have only gas-generation potential. The results also show that the studied coals display relatively lower random vitrinite reflectance (%Rr 0.75–0.82%) and calculated Tpeak values (113–123ºC) using %Rr and micro-Raman spectra than their counterparts in the northern parts of the Basin (%Rr 1.18–1.52% and 173–206ºC). This difference seems to be related to the shallower burial depths of the studied coals or to the fact that they experienced relatively lower maximum attained temperatures than the northern parts of the Basin. Furthermore, the coal petrography and SEM-EDS data also suggest that the post-coalification tectonic deformation in the study area created space for circulating Ca- and Sirich solutions within the coal seams and controlled epigenetic mineralization. Nevertheless, the redox conditions and clastic influx into the palaeomires also controlled syngenetic mineral formations, similar to the other parts of the Basin.

During the Cenomanian–Turonian interval, Europe was largely submerged under a shallow tropical sea within the Cretaceous Tethyan Archipelago, limiting non-marine lacustrine habitats to a few coastal lakes on the islands. This study reports an island refugium for charophytes in the Upper Cretaceous of Tarragona located at the palaeo-shores of the former Ebro Massif. The Upper Cretaceous of Tarragona comprises three carbonate formations that record a Cenomanian–Turonian transgressive-regressive sequence. This sequence is represented by a shallow marine platform to pelagic facies at the base, overlain by lacustrine and palustrine facies at the top. These non-marine deposits are newly attributed to the Turonian, based on the stratigraphic context and the presence of the species Atopochara trivolvis var. multivolvis. In addition to this dominant species, the charophyte assemblage contains a clavatoroidean species, represented by the thallus Munieria grambastii forma sarda, and is associated with freshwater gastropods. A. trivolvis var. multivolvis had a wide distribution in the Northern Hemisphere at a palaeolatitude of around 40ºN, occurring in the United States, Spain, France, and Armenia. The European localities suggest that the island charophyte flora in the Cretaceous Tethyan Archipelago was an impoverished version of the prehighstand Early Cretaceous flora, which was dominated by clavatoraceans. This contrasts with coeval floras from the mainland (Chinese and Argentinian basins), where Turonian charophyte communities were diverse and already dominated by modern characean genera. The island lakes acted as refugia for the last clavatoracean-dominated charophyte communities before their complete replacement by modern characean communities during the latest Cretaceous.

A multiproxy study of the lower Pliocene (Zanclean) shallow lacustrine succession in the southwestern margin of the Baklan Basin (southwestern Anatolia, Türkiye) provides new insights into the paleoclimatic and paleohydrologic evolution of an extensional basin located at the top of the western Taurides mountain range in the southeastern Mediterranean region. Detailed petrographic, sedimentological, palynological and stable isotope analyses on Mg-rich carbonates were carried out on the dolomitic succession in the Sapaca locality in the basin, indicating a vegetated, quiet to slow-moving, low-gradient, perennial, alkaline shallow lake environment under warm and arid climate conditions. The stable isotopic analysis of the dolomitic carbonates exhibits a narrow range of values (-1.31<δ18O<+5.82‰ and -7.10<δ13C<-2.10‰) and the δ18O–δ13C correlation (r= 0.70) indicates a hydrologically closed lake. Two types of dolomite are identified in the studied section. Type-1 crystals formed mainly as a result of primary precipitation of dolomite in the shallow lake, whereas type-2 crystals probably indicate microbially controlled dolomite precipitation. The palynological record from Sapaca reveals that the early Pliocene paleoenvironment was dominated by steppe and open vegetation with some isolated shrubs. Similar paleoclimatic and paleovegetational conditions are observed in other Anatolian basins and in the southern Mediterranean region. Therefore, the results of this study demonstrate that the shallow lacustrine system of the Baklan Basin serves as a good analogue for understanding early Pliocene warmth and aridity in this region.

Some aspects on the age and correlation of the upper Barremian-lower Aptian stratigraphic units of the NW Maestrat Basin were uncertain prior to this study, due to the differing lithostratigraphy of the marginal Oliete subbasin compared to the more depocentral Galve and Morella subbasins. New magnetostratigraphic, ammonite and sedimentological data presented in this study refine the age and sequence stratigraphy of the upper Barremian-lower Aptian succession, enabling a direct and precise correlation across these subbasins. Three third-order TR sequences are identified. The lower boundary of Sequence 1 corresponds to a transgressive surface found on top of the continental red beds of the lower Morella Fm. These beds are equivalent in age to the continental succession of the upper Blesa Fm. (Oliete subbasin). The boundary between the M1 and M0r magnetozones (latest Barremian) is found above this surface, in the lower part of the Alacón Fm. Sequence 1 includes the lower part of the Alacón Fm., which passes basinwards to the upper Morella and Xert formations. Sequence 2 corresponds to the upper part of the Alacón Fm and basinwards to the Cap de Vinyet and Barra de Morella members of the Forcall Fm. The boundary between the M0r and C34n magnetozones (earliest Aptian) is found towards the lowermost part of Sequence 2. Sequence 3 includes the Josa Fm and its offshore equivalents, the Morella la Vella Mb. and the Villarroya de los Pinares Fm. Additionally, the overall facies distribution in successive depositional stages is reconstructed, describing the lateral transition from marginal protected to open marine areas. The improved chronostratigraphic framework presented here will enable more accurate correlations with other subbasins of the Maestrat Basin, and the reconstructed sedimentary evolution may be useful for the interpretation of other Lower Cretaceous successions of the Tethys.

Two decapod (Arthropoda: Malacostraca: Decapoda) assemblages from two newly discovered localities near Torreblanca (Castelló, Valencian Country, Spain), situated in the Orpesa Sub-basin of the Maestrat Basin, are described. The first assemblage exhibits a diverse fauna of lobsters, including erymoids, glypheoids and nephropoids representatives of five different genera, some of them reported for the first time in Iberia, as well as brachyuran crabs, primarily palaeocorystoids, including one new species, Paranecrocarcinus xivertensis. It is assigned to the uppermost Aptian of the Benassal Formation. The second assemblage, found in the lower Albian Escucha Formation, showcases an exceptional richness of exquisitely preserved complete remains of a new genus and species of axiidean ghost shrimp, Cretagourretia salasi, along with some palaeocorystoids, also representatives of a new species, Joeranina tausi, within a varied community of invertebrates and plants. This work investigates the paleoenvironment in which these assemblages thrived, and explores their faunal similarities with other decapod assemblages from the nearby Garraf Basin, as well as more distant ones such as the Basque-Cantabrian Basin and the Isle of Wight. An ammonite occurrence, likely belonging to the genus Roberticeras, has been identified in the upper Aptian Benassal Formation. Additionally, the juvenile stage of the ammonite Parengonoceras bassei from the lower Albian Escucha Formation is reported and described for the first time. The study provides valuable insights into reconstructing coastal to marine environments and the associated biota that developed in the Maestrat Basin during the Aptian-Albian transition.