Synchronous exhumation episodes across Arctic Canada, North Greenland and Svalbard in relation to the Eurekan Orogeny

Shallow Thermal Anomalies and Their Role in the Breakup Evolution Along the Conjugate Margins of the Fram Strait (Svalbard and Eastern North Greenland), Indicated by Low‐Temperature Thermochronology

“…Accordingly, we interpret Prins Karls Forland as a horst, which was exhumed and thus cooled during the Oligocene in response to the formation of the Forlandsundet Graben. In addition to Pearya and Prins Karls Forland, Oligocene exhumation is also described for other areas of the Arctic (Bonow et al, 2014;Bonow & Japsen, 2021;Japsen et al, 2021Japsen et al, , 2023 (Note that Japsen et al (2023) reported Oligocene exhumation also for the Wandel Sea Basin including Nakkehoved and the Thyra Ø Formation. It is not clear from their study whether Oligocene cooling is constraint-driven or actually required by their thermochronology data.…”

“…Opening and subsequent widening and deepening of the Fram Strait was related to the uplift of pre-Miocene erosion surfaces in Greenland and Svalbard (Bonow & Japsen, 2021;Dörr et al, 2013;Dörr, Lisker, Piepjohn, & Spiegel, 2019), and to the formation of a middle to late Miocene unconformity in the offshore sediments of the Greenland shelf, detected by seismic data (Døssing et al, 2016). Previous thermal history models of thermochronology data from Greenland and Svalbard also frequently involve middle or late Miocene cooling (Blythe & Kleinspehn, 1998;Dörr et al, 2013;Dörr, Lisker, Piepjohn, & Spiegel, 2019;Japsen et al, 2021Japsen et al, , 2023, but these cooling periods are poorly constrained and differ in terms of their timing. We included Miocene cooling as a constraint in our thermal history inversions.…”

“…This led eventually to the opening of the Fram Strait, connecting the spreading centers of the Arctic and the North Atlantic oceans. During the middle Miocene, the Greenland and Barents margins experienced uplift (Bonow & Japsen, 2021;Dörr et al, 2013;Dörr, Lisker, Piepjohn, & Spiegel, 2019;Japsen et al, 2023), associated with a regional unconformity in the offshore seismic record (Døssing et al, 2016), and accompanied by magmatic activity (Geissler et al, 2019;Prestvik, 1978;Sushchevskaya et al, 2009). Døssing et al (2016) related these changes to a changed stress regime along the Greenland Fracture Zone-segment of the DGFZ, coeval with accelerated widening of the Fram Strait.…”

“…(b) Transpessive/compressive phase of Eureka deformation at the Svalbard-Greenland margin with De Geer Fracture Zone (DGFZ) activity and onset of volcanism at the Yermak Plateau and the Vestbakken Volcanic Province in the early Eocene (Faleide et al, 2010;Piepjohn et al, 2016;Riefstahl et al, 2013). Thyra Ø Basin and the Central Tertiary Basin were heated while the geothermal gradient decreased and cooling due to inversion of fault zones occurred partially (Barnes & Schneider, 2019;Dörr, Lisker, Jochmann, et al, 2019;Japsen et al, 2021Japsen et al, , 2023. (c) Transtensive phase of the Eurekan with progressive lateral offset and enhanced heat flow along the DGFZ.…”

“…Between the Carboniferous and the Early Cretaceous, the basins of Svalbard and eastern North Greenland evolved in a similar way, but from the Late Cretaceous onwards, both areas experienced different geological developments: While Late Cretaceous deposits are widely exposed in North Greenland (e.g., in Nakkehoved, Kilen, or in the Kap Washington area), they are lacking on Svalbard (except for a possible occurrence in the Sørkapp Land of Spitsbergen; Krutzsch, 2001; Smelror & Larssen, 2016). During the Late Cretaceous, North Svalbard and the wider area of the Barents Shelf experienced a period of enhanced exhumation (Dörr et al., 2012; Dörr, Lisker, Piepjohn, & Spiegel, 2019; Japsen et al., 2023; Lasabuda et al., 2021). Paleogene deposition started with the Paleocene to Eocene coastal to shallow marine sandstones, siltstones and shales of the Van Mijenfjorden Group and its equivalents in the Central Tertiary Basin and on Brøggerhalvøya, respectively (Figures 2b and 3; Dallmann, 1999, 2015).…”