Plate corners that transition from subduction to transform motion can result in complex deformation. The southeastern corner of the Caribbean plate is a site where active westward subduction of the oceanic South American plate transitions to transform motion along continental South America. The Northern Range (Trinidad) and Paria (Venezuela) metamorphic mountains are located directly above this eastward propagating plate transition zone. We examined the exhumation history of the Northern Range and eastern Paria using apatite fission track (AFT) and apatite and zircon (U‐Th)/He (AHe and ZHe, respectively) thermochronology on 21 bedrock samples. These samples yield ages of ∼43–6 Ma (ZHe: aliquots), ∼20–4 Ma (AFT: pooled) and ∼5–2 Ma (AHe: aliquots). Along strike of the mountains, our new and published samples show a gradual eastward increase in age. Thermal modeling reveals two phases of rapid cooling and inferred exhumation that post‐dates oblique collision and that migrated from west to east. We record an ∼six‐fold increase in cooling and exhumation between ∼13–9 Ma in the Paria Peninsula and western Northern Range; a deceleration followed this rapid exhumation at ∼7 and 5 Ma. Synchronous with the deceleration in the west, exhumation of the eastern Northern Range increased ∼4 Ma. These post‐collisional changes in exhumation constrain the inversion to east‐side‐up tilting of the Northern Range to ∼4 Ma. We interpret the timing and pattern of exhumation since the mid‐Miocene to be consistent with the time‐transgressive processes produced by an eastward propagating lithospheric subduction‐transform edge propagator fault.

The Late Cenozoic is typically considered a time of widespread episodic tectonic uplift along the West Greenland continental margin (36-2 Ma), similar to other margins across the North Atlantic, such as Norway, East Greenland and the UK. The present study re-examines and remodels onshore thermochronological data from central West Greenland and the Cretaceous Nuussuaq Basin, utilising a Bayesian modelling approach and new concepts related to radiation damage within apatite. These new thermal histories indicate that slow-protracted cooling has occurred across the southern extent of the margin during the Mesozoic and Cenozoic, whereas those from within the Nuussuaq Basin display reheating through the Late Cretaceous/Palaeogene and cooling to present. Results suggest that no significant Late Cenozoic uplift has occurred along the southern margin, while cooling in the Nuussuaq Basin is consistent with events outlined in the basin's stratigraphy and implies uplift during volcanism and an isostatic response to the unroofing of the lithosphere has elevated the modern topography. These results imply significant tectonism in the region ceased by~45 Ma, yet have wider implications regarding how low temperature thermochronology data are treated and our understanding of the postrift evolution of passive margins. K E Y W O R D Smodelling, passive margins, stratigraphy, tectonics and sedimentation, thermochronology

Intraplate basin/structural inversion (indicating tectonic shortening) is a good marker of ("far-field") tectonic stress regime changes that are linked to plate geometries and interactions, a premise that is qualitatively well-established in the literature. There is also quantitative evidence that Late Cretaceous-Palaeocene inversion of sedimentary basins in north-central Europe was explicitly driven by an intraplate, relaxational response to forces developed during rapid reconfigurations of the Alpine-Tethys (Europe-Africa) convergent plate boundary. Although with a degree of temporal ambiguity, three main periods of intraplate tectonics (marked primarily by structural inversion in initially extensional sedimentary basins) are indicated in the North Atlantic-western Alpine-Tethys realm. These are in the Late Cretaceous-Palaeocene, the Eocene-Oligocene and the Miocene. Examples recording these periods are primarily interpreted seismic reflection profiles (of varying quality and resolution) from the published literature. Additional examples where seismic data are not present, but timing constraints are robust from other observations, have also been considered. The schematic distribution and orientation of the literature-compiled intraplate inversion structures are compared to the model palaeostress fields derived from Late Cretaceous-Palaeocene, Eocene-Oligocene and Miocene tectonic reconstructions of the North Atlantic-western Alpine-Tethys realm. The modelled palaeostress fields include geopotential effects from palaeobathymetry and palaeotopography of the Earth's surface as well as laterally variable lithosphere and crustal palaeothicknesses but do not include any component of the stress field produced by processes occurring at contiguous convergent plate margins. The former satisfactorily provides the background stress field of most of the Earth's plate interiors and it is inferred that the latter is paramount in producing "stress trauma" in the interior of plates resulting in permanent intraplate deformation such as basin inversion.

The two branches of the East African Rift System (EARS) are believed to have initiated diachronously. However, a growing body of work continues to suggest the onset of rifting in the Western Branch occurred in the Palaeogene, coeval to the Eastern Branch. Due to a lack of pre-Miocene stratigraphy, attempts to resolve the geological history of the Western Branch must study the uplift and erosional histories of the modern rift topography. In this study, the rock uplift history of the Rwenzori Mountains, Western Uganda, is resolved to better our understanding of the tectonic history of the Western Branch of the EAR. Through the application of low-temperature thermochronology, -mapping and the modelling of river profiles, we show that rock uplift of the Rwenzori dates back to the Oligocene, with thermal history models suggesting uplift induced exhumation may date back as far as the Eocene. This provides tangible evidence that extension began in the region in the Paleogene, coeval with the Eastern Branch, and not the late Neogene. These results have broad implications for the tectonic evolution of the entire East African Rift System and suggest our current understanding of the region's rift history remains incomplete.

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