Tectonic significance of changes in post-subduction Pliocene-Quaternary magmatism in the south east part of the Carpathian-Pannonian Region

The south-eastern part of the Carpathian–Pannonian region records the cessation of convergence between the European platform/Moesia and the Tisza–Dacia microplate. Plio-Quaternary magmatic activity in this area, in close proximity to the ‘Vrancea zone’, shows a shift from normal calc-alkaline to much more diverse compositions (adakite-like calc-alkaline, K-alkalic, mafic Na-alkalic and ultrapotassic), suggesting a significant change in geodynamic processes at approximately 3 Ma. We review the tectonic setting, timing, petrology and geochemistry of the post-collisional volcanism to constrain the role of orogenic building processes such as subduction or collision on melt production and migration. The calc-alkaline volcanism (5.3–3.9 Ma) marks the end of normal subduction-related magmatism along the post-collisional Călimani–Gurghiu–Harghita volcanic chain in front of the European convergent plate margin. At ca. 3 Ma in South Harghita magma compositions changed to adakite-like calc-alkaline and continued until recent times (< 0.03 Ma) interrupted at 1.6–1.2 Ma by generation of Na and K-alkalic magmas, signifying changes in the source and melting mechanism. We attribute the changes in magma composition in front of the Moesian platform to two main geodynamic events: (1) slab-pull and steepening with opening of a tear window (adakite-like calc-alkaline magmas) and (2) renewed contraction associated with deep mantle processes such as slab steepening during post-collisional times (Na and K-alkalic magmas). Contemporaneous post-collisional volcanism at the eastern edge of the Pannonian Basin at 2.6–1.3 Ma was dominated by Na-alkalic and ultrapotassic magmas, suggesting a close relationship with thermal asthenospheric doming and strain partitioning related to the Adriatic indentation. Similar timing, magma chamber processes and volume for K-alkalic (shoshonitic) magmas in the South Apuseni Mountains (1.6 Ma) and South Harghita area at a distance of ca. 200 km imply a regional connection with the inversion tectonics

Origin of basaltic magmas of Perşani volcanic field, Romania: A combined whole 6 rock and mineral scale investigation

The Perşani volcanic field is a low-volume flux monogenetic volcanic field in the Carpathian–Pannonian region, 24 eastern-central Europe. Volcanic activity occurred intermittently from1200 ka to 600 ka, forming lava flow fields, 25 scoria cones andmaars. Selected basalts fromthe initial and younger active phaseswere investigated for major and 26 trace element contents and mineral compositions. Bulk compositions are close to those of the primitive magmas; 27 only 5–12% olivine and minor spinel fractionation occurred at 1300–1350 °C, followed by clinopyroxenes at about 28 1250 °C and 0.8–1.2 GPa. Melt generation occurred in the depth range from 85–90 km to 60 km. The estimated 29 mantle potential temperature, 1350–1420 °C, is the lowest in the Pannonian Basin. It suggests that no thermal 30 anomaly exists in the uppermantle beneath the Perşani area and that themaficmagmas were formed by decom- 31 pressionmelting under relatively thin continental lithosphere. Themantle source of themagmas could be slightly 32 heterogeneous, but is dominantly variously depleted MORB-source peridotite, as suggested by the olivine and 33 spinel composition. Based on the Cr-numbers of the spinels, two coherent compositional groups (0.38–0.45 and 34 0.23–0.32, respectively) can be distinguished that correspond to the older and younger volcanic products. This in- 35 dicates a change in themantle source region during the volcanic activity as also inferred from the bulk rockmajor 36 and trace element data. The younger basaltic magmas were generated by lower degree of melting, from a deeper 37 and compositionally slightly different mantle source compared to the older ones. The mantle source character of 38 the Perşanimagmas is akin to that ofmany other alkaline basalt volcanic fields in theMediterranean close to oro- 39 genic areas. The magma ascent rate is estimated based on compositional traverses across olivine xenocrysts using 40 variations of Ca content. Two heating events are recognized; the first one lasted about 1.3 years implying heating 41 of the lower lithosphere by the uprisingmagma,whereas the second one lasted only 4–5 days,whichcorresponds 42 to the time of magma ascent through the continental crust. The alkaline mafic volcanismin the Perşani volcanic 43 field could have occurred as a response to the formation of a narrow rupture in the lower lithosphere, possibly 44 as a far-field effect of the dripping of dense continental lithospheric material beneath the Vrancea zone. Upper 45 crustal extensional stress-field with reactivation of normal faults at the eastern margin of the Transylvanian 46 basin could enhance the rapid ascent of the mafic magmas

Toward understanding the post-collisional evolution of an orogen influenced by convergence at adjacent plate margins; Late Cretaceous-Tertiary thermotectonic history of the Apuseni Mountains

The relationship between syn- to post-collisional orogenic shortening and stresses transmitted from other neighboring plate boundaries is important for understanding the kinematics of mountain belts, but has received little attention so far. The Apuseni Mountains are an example of an orogen in the interference zone between two other subduction systems located in the external Carpathians and Dinarides. This interference is demonstrated by the results of a combined thermochronological and structural field study that quantifies the post-collisional latest Cretaceous-Tertiary evolution. The exhumation history derived from apatite fission track and (U-Th)/He thermochronology indicates that the present-day topography of the Apuseni Mountains originates mainly from latest Cretaceous times, modified by two tectonic pulses during the Paleogene. The latter are suggested by cooling ages clustering around ∼45 Ma and ∼30 Ma and the associated shortening recorded along deep-seated fault systems. Paleogene exhumation pulses are similar in magnitude (∼3.5 km) and are coeval with the final collisional phases recorded in the Dinarides and with part of the Carpathian rotation around the Moesian promontory. These newly quantified Paleogene exhumation and shortening pulses contradict the general view of tectonic quiescence, subsidence and overall sedimentation for this time interval. The Miocene collapse of the Pannonian Basin did not induce significant regional exhumation along the western Apuseni flank, nor did the subsequent Carpathian collision. This is surprising in the overall context of Pannonian Basin formation and its subsequent inversion, in which the Apuseni Mountains were previously interpreted as being significantly uplifted in both deformation stages. Copyright 2011 by the American Geophysical Union

Сверхлегкие генераторные модули для КВЧ-терапии

Разработаны миниатюрные генераторные модули для КВЧ-терапии, лег-ко фиксируемые в любом месте тела пациента. Могут быть использованы не только в медицине

Contribuţii la cunoaşterea obiectelor de os şi corn de cerb din Municipium Septimium Apulense. Descoperiri recente / Contributions to the study of bone and deer antler artefacts from Municipium Septimium Apulense. Recent discoveries

The authors present a batch of 81 items made of bone and antler found in 2016 and 2017 in Alba Iulia, in the southern sector of Municipium Septimium Apulense, with the occasion of preventive archaeological researches. Based on the discovered fibula, the bone and antler pieces were chronologically dated to the 3rd century, more precisely, from the beginning of the century to the Aurelian withdrawal. The vast majority of items were discovered in 2017. Among them two unfinished pieces were identified. In our opinion this speaks for the existence in the researched area or in its proximity of a small workshop for bone and antler processing. The discovered items belong to the following categories : toiletries and adorments (bone hair pins, a deer antler pendant), household items (needles, needle boxes, perforators), gaming pieces (tokens), a musical instrument (whistle), a medical instrument (spatula), and some fragile pieces with uncertain attribution. Significant quantities of objects made of bone and red deer antler have been discovered in the Roman canabae / municipium Septimium Apulense during the archaeological excavations, both preventive and systematic, undertaken so far. Most of them are already assesed in the scientific literature. This recently discovered artefacts are useful to complete our information about this category of items from Dacia in general and from Apulum in particular.Autorii prezintă un lot format din 81 de obiecte, obținute din os și din corn, descoperite în anii 2016 și 2017, la Alba Iulia, în sectorul sudic al Municipium Septimium Apulense, cu ocazia unor cercetări arheologice preventive. Pe baza unora dintre fibulele descoperite, piesele de os și corn au fost încadrate cronologic în secolul al III-lea, mai precis, în intervalul cuprins între începutul secolului și retragerea aureliană. Aproape toate obiectele au fost descoperite în cercetarea întreprinsă în anul 2017. Între acestea, au fost identificate și două piese în curs de prelucrare, datorită cărora luăm în considerare posibilitatea ca, în zona cercetată de noi sau în proximitatea ei, să fi existat un mic atelier de prelucrare a osului și cornului. Amintim aici categoriile de obiecte descoperite : piese de toaletă și podoabă (ace de păr de os, un pandantiv de corn de cerb), piese de uz casnic (ace de cusut, cutii pentru ace, străpungătoare), piese pentru jocuri (jetoane), un instrument muzical (fluier), un instrument medical (spatulă) și câteva piese fragmentare cu atribuire incertă. În cercetările arheologice preventive și sistematice întreprinse până în prezent în canabele romane / municipium Septimium Apulense, au fost descoperite importante cantități de obiecte realizate din os și din corn. Cele mai multe dintre acestea au fost introduse în literatura de specialitate. Piesele publicate în prezentul articol ajută la completarea informațiilor cunoscute despre această categorie de artefacte descoperite la Apulum, în special, și în Dacia, în general.Bleoancă Mihaela, Ciulavu Florin. Contribuţii la cunoaşterea obiectelor de os şi corn de cerb din Municipium Septimium Apulense. Descoperiri recente / Contributions to the study of bone and deer antler artefacts from Municipium Septimium Apulense. Recent discoveries. In: Materiale şi cercetãri arheologice (Serie nouã), N°15 2019. pp. 123-155