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<jats:title>Abstract</jats:title><jats:p>In this study, we combined the geochemical characteristics based on Rock-Eval pyrolysis and gas chromatography – mass spectrometry (GC–MS) results with the facies analysis. These surveys were conducted within grey to black claystones/mudstones intervals of the Podil’tsi and Kokhanivka formations, related to the Pliensbachian and Toarcian–Bathonian ages, respectively. The geochemical results revealed that the Podil’tsi Formation contains mixed marine/terrigenous, early-mature to mature organic matter. The deposition of this formation took place in dysoxic redox conditions of a sulphate-poor marine palaeoenvironment, with oxygen scarcity within the photic zone, as documented by green- and brown-pigmented Chlorobiaceae. Oleanane is present within the samples from the Podil’tsi Formation, which is uncommon within Lower Jurassic sedimentary rocks. The Kokhanivka Formation contains mostly early-mature, terrestrial organic matter, deposited in suboxic conditions of a sulphate-poor, fluvial–deltaic palaeoenvironment. The absence of aliphatic diterpenoids within the Middle Jurassic strata points to the low significance of conifers in the sediment supply area at this time. All of the Podil’tsi and most of the Kokhanivka formations are characterised by poor hydrocarbon potential. Only the middle part of the Kokhanivka Formation, built by brown, organic-rich claystones, shows fair-to-good hydrocarbon potential. Based on our results, a chemostratigraphic correlation of the Toarcian–Bathonian strata from the Carpathian Foredeep with the same strata from the neighbouring Polish Basin was performed. The juxtaposition of the geochemical and facies results suggests that the interval of brown organic-rich claystones, from the middle part of the Kokhanivka Formation can be related to the Middle–Upper Aalenian Age.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The Rhodope crystalline massif is an Alpine metamorphic complex exposed across several mountain ranges in southern Bulgaria and northern Greece which has experienced a complex history including continental collision, partial subduction and syn-metamorphic nappe stacking followed by syn- to post-contractional extension. We present new <jats:sup>40</jats:sup>Ar/<jats:sup>39</jats:sup>Ar and fission-track data from samples taken from both sides of the North Rhodopean Detachment that were combined with detailed structural studies to investigate the tectonothermal evolution of the northern Rila Mountains. A migmatite from the hanging wall of the North Rhodopean Detachment yields a <jats:sup>40</jats:sup>Ar/<jats:sup>39</jats:sup>Ar muscovite age of 100.79 ± 0.55 Ma, a zircon fission-track age of 38.6 ± 1.9 Ma, and an apatite fission-track age of 21.4 ± 1.5 Ma. A biotite schist from the footwall of the detachment yields <jats:sup>40</jats:sup>Ar/<jats:sup>39</jats:sup>Ar biotite age of 34.90 ± 0.15 Ma, and zircon and apatite fission-track ages of 35.6 ± 5.6 and 13.3 ± 1.1 Ma, respectively. Our new data give evidence of a multistage exhumation of the study area. Late Early Cretaceous (~ 101 ± 0.6 Ma) cooling of the Variscan high-grade metamorphic basement through 440–400 °C was caused by either erosion of the emplacing thrust sheet, or post-contractional denudation. Fast exhumation along the North Rhodopean Extensional System drove a pulse of increased tectonic denudation and cooling during the Eocene (39–35 Ma). Exhumation of the rocks in the northern part of the Rila Mountains below 110 ± 10 °C during the middle–late Miocene was associated with displacement along a system of normal faults.</jats:p>

<jats:sec> <jats:title>Abstract</jats:title> <jats:p>Geochemical and geochronologic data are presented for meta-mafic to meta-felsic rocks along the Paleo-Tethys Suture in the Binalood Mountains east of Neyshabur, NE Iran. The rocks have a late Cambrian age (U–Pb zircon, ~ 490 Ma) and were metamorphosed in the Early Jurassic (<jats:sup>40</jats:sup>Ar/<jats:sup>39</jats:sup>Ar amphibole and plagioclase, 199–192 Ma). The rocks of this suite are alkaline and sub-alkaline (tholeiitic). The alkaline rocks are enriched in light relative to heavy rare earth elements, and do not show depletion of high-field strength elements on primitive mantle-normalized multi-element diagrams; they are similar to ocean island basalts (OIB). The tholeiitic rocks are depleted in Nb and Ta and have higher MgO and lower TiO<jats:sub>2</jats:sub> than the alkaline rocks. Both types have similar, high and variable <jats:sup>87</jats:sup>Sr/<jats:sup>86</jats:sup>Sr<jats:sub>(i)</jats:sub> isotopic compositions of 0.7044 to 0.7082 and <jats:sup>143</jats:sup>Nd/<jats:sup>144</jats:sup>Nd<jats:sub>(i)</jats:sub> values of 0.5118 to 0.5122. The alkaline rocks are lower-degree partial melts than the tholeiitic rocks and were generated at greater depths; they likely originated from a garnet pyroxenite-rich source. The spatial, temporal, and geochemical relationships of early Paleozoic meta-mafic to felsic rocks along the Paleo-Tethys Suture (e.g., Shahrud, Jajarm, Binalood, Torbat-e-Jam) substantiate the role of a mantle plume in continental breakup along the northern margin of Gondwana and a late Cambrian-Ordovician onset of rifting that resulted in the opening of the Paleo-Tethys Ocean. The Early Jurassic metamorphism post-dates its closure.</jats:p> </jats:sec><jats:sec> <jats:title>Graphical abstract</jats:title> </jats:sec>