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This work presents new apatite fission track LA–ICP–MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometry) data from Mid–Late Paleozoic rocks, which form the substratum of the Swiss Jura mountains (the Tabular Jura and the Jura fold-and-thrust belt) and the northern margin of the Swiss Molasse Basin. Samples were collected from cores of deep boreholes drilled in North Switzerland in the 1980s, which reached the crystalline basement. Our thermochronological data show that the region experienced a multi-cycle history of heating and cooling that we ascribe to burial and exhumation, respectively. Sedimentation in the Swiss Jura Mountains occurred continuously from Early Triassic to Early Cretaceous, leading to the deposition of maximum 2 km of sediments. Subsequently, less than 1 km of Lower Cretaceous and Upper Jurassic sediments were slowly eroded during the Late Cretaceous, plausibly as a consequence of the northward migration of the forebulge of the neo-forming North Alpine Foreland Basin. Following this event, the whole region remained relatively stable throughout the Paleogene. Our data show that the Tabular Jura region resumed exhumation at low rates in early–middle Miocene times (≈20–15 Ma), whereas exhumation in the Jura fold-and-thrust belt probably re-started later, in the late Miocene (≈10–5 Ma). Erosional exhumation likely continues to the present day. Despite sampling limitations, our thermochronological data record discrete periods of slow cooling (rates of about 1°C/My), which might preclude models of elevated cooling (due to intense erosion) in the Jura Mountains during the Miocene. The denudation (≈1 km) of the Tabular Jura region and the Jura fold-and-thrust belt (≈500 m) has provided sediments to the Swiss Molasse Basin since at least 20 Ma. The southward migration of deformation in the Jura mountains suggests that the molasse basin started to uplift and exhume only after 5 Ma, as suggested also by previous authors. The data presented here show that the deformation of the whole region is occurring in an out-of-sequence trend, which is more likely associated with the reactivation of thrust faults beneath the foreland basin. This deformation trend suggests that tectonics is the most determinant factor controlling denudation and exhumation of the region, whereas the recently proposed “climate-induced exhumation” mechanism might play a secondary role.

The Cameros Basin (North Spain) is a Late Jurassic-Early Cretaceous extensional basin, which was inverted during the Cenozoic. It underwent a remarkable thermal evolution, as indicated by the record of anomalous high temperatures in its deposits. In this work the subsidence and thermal history of the basin is reconstructed, using subsidence analysis and 2D thermal modeling. Accepted ArticleThis article is protected by copyright. All rights reserved.

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The intraplate Cameros Rift Basin in northern Spain, which has sediments some 6500 m thick, developed between the Late Jurassic and Early Albian. Its facies and their distribution in the sedimentary record suggest the basin may contain hydrocarbon systems. The arenite composition of the basin reveals two main petrofacies: (1) a quartzolithic petrofacies, the provenance of which is related to recycling processes that took place in the pre-rift sedimentary cover; and (2) a quartzofeldspathic petrofacies mainly related to the erosion of a plutonic and metamorphic source of arenite. The succession of these petrofacies reflects two main cycles representing the progressive erosion of their sources, one of 10 Ma, the other of 30 Ma. Such succession is typical of a non-volcanic rift basin. The quartzolithic petrofacies shows early carbonate cements that inhibited compaction and later quartz, feldspar and clay mineral diagenetic phases. The quartzofeldspathic petrofacies has a rigid framework that maintained the original pores of the arenite during burial diagenesis. Quartz and K-feldspar overgrowths are common, with secondary porosity occurring as a product of feldspar dissolution. The quartzofeldspathic petrofacies has a greater potential to act as a hydrocarbon reservoir. This study corroborates the close relationship between the provenance of arenite and its reservoir potential in continental rift basins.