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Northern Svalbard represents a basement high surrounded by the Norwegian‐Greenland Sea/Fram Strait, Eurasian Basin, the Barents Shelf and the onshore Central Tertiary Basin (CTB). Published apatite fission track (AFT) data indicate Mesozoic differential, fault‐controlled uplift and exhumation of the region. Thermal history modelling of published and new AFT and (U–Th–Sm)/He ages of 51–153 Ma in the context of regional stratigraphy and geomorphology implies at least two, possibly three, uplift and exhumation stages since late Mesozoic, separated by episodes of subsidence and sediment deposition. Late Cretaceous/Palaeocene exhumation and subsequent burial appear to be related with the transition of compressional to transpressional collision of Svalbard and Greenland during the Eurekan Orogeny. Renewed exhumation since the Oligocene probably results from passive margin formation after the separation of Svalbard and Greenland, when a new offshore sedimentary basin opened west of Svalbard. Final uplift since the Miocene eventually re‐exposed the palaeosurface of northern Svalbard. [ABSTRACT FROM AUTHOR]

• 1st low temperature thermochronological age-elevation profiles of the IBR, Myanmar. • Major exhumation around the Oligo-Miocene boundary; possible earlier event by latest Eocene. • Divergence of provenance east and west of IBR by Miocene, consistent with timing of uplift. The Indo-Burman Ranges (IBR) are a mountain range comprised of Mesozoic-Cenozoic rocks which run the length of Western Myanmar, extending into India and Bangladesh; to the west lies the Indian Ocean, and to the east lies the Central Myanmar Basin (CMB) along which the Irrawaddy River flows. The IBR are considered to be an accretionary prism, developed at the juncture of the Indian and Sunda plates, and a number of hypotheses have been proposed for their evolution. However, in order for these hypotheses to be evaluated, the timing of IBR evolution needs to be determined. We undertook a two-pronged approach to determining the timing of uplift of the IBR. (1) We present the first low-temperature thermochronological age elevation profiles of the IBR using ZFT, AFT and ZHe techniques. Our data show: a major period of exhumation occurred around the time of the Oligo-Miocene boundary; we tentatively suggest, subject to further verification, an additional period of exhumation at or before the late Eocene. (2) We carried out a detailed multi-technique provenance study of the sedimentary rocks of the IBR and Arakan Coastal region to their west, and compared data to coeval rocks of the CMB. We determined that during Eocene times, rocks of the CMB and IBR were derived from similar local provenance, that of the Myanmar arc to the east. Therefore at this time there was an open connection from arc to ocean. By contrast, by Miocene times, provenance diverged. Rocks of the CMB were deposited by a through-flowing Irrawaddy River, with detritus derived from its upland source region of the Mogok Metamorphic Belt and Cretaceous-Paleogene granites to the north. Such a provenance is not recorded in coeval rocks of the IBR, indicating that the IBR had uplifted by this time, providing a barrier to transport of material to the west. To the previously published list of viable proposals to explain the exhumation of the range, we add a new suggestion: the period of exhumation around the time of the Oligo-Miocene boundary could have been governed by a change to wedge dynamics instigated by a major increase in the thickness of the incoming Bengal Fan sediment pile. [ABSTRACT FROM AUTHOR]

The Arctic history is characterized by high complexity with the Eocene Eurekan Orogeny representing one of the most important tectonic events. It resulted from plate re-organisation and opening of North Atlantic Ocean. Related to that, multiple and changing tectonic regimes affected the wider region, causing differentiated deformation in the different parts of the Arctic Ocean margin. Our study focuses on the area of northern Ellesmere Island (Canadian High Arctic), the northernmost land exposures studied so far. We investigate the temporal and spatial exhumation patterns along the western part of the Eurekan orogen in relation to the wider geotectonic settings. For this, we applied low-temprerature thermochronology (apatite fission track and (U-Th-Sm)/He) methods, along with palynological analysis from Paleocene to Early Eocene sedimentary deposits, and we correlate the results with the history of the spreading ridges in North Atlantic, as well as with climatic changes in the Arctic. Our data show that from Palaeocene to Oligocene, significant exhumation occurred along the Canadian Arctic margin. This was episodic, and highly differentiated from exhumation documented for southern Ellesmere Island. This difference may be well explained by considering our study area as part of a mega-transform-fault-system that extends all the way to Svalbard and NE Greenland. The activity of major strike-slip fault segments, according to the changing tectonic regimes, may have been responsible for increased exhumation and intermittent periods of quiescence. Since the Palaeocene, we distinguish four main periods of enhanced exhumation: (i) ~64-59 Ma (pre-Eurekan), related to crustal stretching and basin formation during the Paleocene, contemporaneously to the opening of the Baffin Bay / Labrador Sea; (ii) ~55 to 48 Ma (Eurekan I), related to strike-slip regime with continuation of deposition in the earlier formed Palaeocene basins, and controlled by the initiation of the Norwegian-Greenland Sea opening. Sediment deposition (that started already in the Palaeocene) occurred in a coastal swamp environment under a warm and humid climate that lasted into the Early Eocene; (iii) ~44 to 38 Ma (Eurekan II), again related to strike-slip movements, leading to rapid exhumation, and presumably to topography build-up and the rise of the Eurekan Belt, and inversion of the Palaeocene basins. This period coincides with the deposition of ice-rafted debris off East Greenland, and therefore we suggest the rise of the Eurekan belt was an important trigger for the formation of continental icecap(s) in Greenland during the Eocene and Oligocene. During this stage, collision between Greenland and the eastern Canadian archipelago may have caused slow-down of spreading rates in the Norwegian-Greenland Sea; and (iv) ~34 to 26 Ma (post-Eurekan), related to strike-slip movements, cessation of Labrador Sea/ Baffin Bay spreading, and unification of Greenland with the North American plate. We explain the cessation of rapid exhumation at ~26 Ma with continental separation between Northeast Greenland and Svalbard due to changes of the active spreading centres in the North Atlantic. This in turns caused decoupling of northern Ellesmere Island from strike-slip movements along the De Geer fault zone, eventually leading to the opening of the Fram Strait. [ABSTRACT FROM AUTHOR]