The Gulf of Mexico (GoM) is one of the most extensively studied offshore regions, but its Mesozoic evolution remains uncertain. The presence of a thick sedimentary cover and Jurassic salt poses challenges for geophysical imaging, hindering our understanding of the Mesozoic depositional history and crustal architecture evolution. Current tectonic models with rigid plates fail to capture key aspects of GoM evolution. This study introduces a new deformable plate model with optimised focused deformation designed to dynamically adjust stretching factors (SF) during rift evolution. Our model, which calculates crustal thickness and tectonic subsidence (TS) through time and accounts for stretching and thermal subsidence, can explain the depositional history of the pre-salt section and crustal architecture evolution of the GoM. Our model produces a predicted present-day crustal thickness with a root mean square error of 5.6 km with the GEMMA crustal thickness model. The resultant TS of ~1.5 km before the Yucatán block drifted, provides routes for the deposition of red beds through the paleo drainage systems of the northern GoM as successor basin infilling. The model explains ~40 Myrs of missing sedimentary strata, which we attribute to rapid subsidence in the central GoM, shifting red beds deposition beneath the Jurassic salt formations. Extension rate and SF calculations reveal a transition from a magma-rich to a hyperextended margin, with possible mantle exhumation. Our model can be useful in understanding the extent of other Jurassic deposits in the GoM basin and offers a robust framework for comprehending global passive rift margin evolution.

The Gulf of Mexico (GoM) is a passive rift margin that is shrouded in thick sedimentary layers, making it challenging to trace its Mesozoic evolution. Traditionally, plate tectonic models have required an assumption of rigid plates, limiting our ability to understand the evolution of passive margins given the wealth of geological and geophysical evidence indicating significant crustal deformation during rifting processes. However, recent advances have been made in our ability to incorporate deformation into plate tectonic models.Here, we present a novel approach to reconstruct the evolution of the GoM by using an optimized and focused deformable plate model. Our new model uses a time-evolving focused deformation along the rift, where the strain rate evolves over time from being more uniform initially to increasing exponentially seaward to the point of continental rupture and ocean crust formation.By incorporating time-evolving deformation into our plate reconstruction, we can additionally derive crustal thickness and thermal and tectonic subsidence through time, which allows us to better explore the depositional history of the presalt deposition and crustal architecture evolution of the GoM basin. Our deformation model is optimized to minimize the root mean squared error (RMSE) between predicted present-day crustal thickness and the GEMMA crustal thickness model, resulting in an RMSE of 5.6 km compared to GEMMA, with <2 km absolute error in the northwest and northeast GoM. The resulting tectonic subsidence of ~1.5 km before the Yucatán block drifted in Late Triassic providing routes for the deposition of red beds through the paleo-drainage systems of the northern GoM as successor basin infilling. We find rapid subsidence occurred in the central GoM during the Early Jurassic shifting red bed deposition to a location that presently lies beneath the salt formation, potentially reconciling ~40 Myrs of missing sedimentary strata. Extension rate and stretching factor calculations reveal a transition from a magma-rich to a hyperextended margin, with possible mantle exhumation.Through our study, we highlight the significance of adopting optimized deformable plate reconstruction models, which enables quantitative interpretations of the tectonic history and geological evolution in rift basins globally.

The Cameroon Volcanic Line (CVL) and other tectonic features in Cameroon remain enigmatic, prompting ongoing debates about their detailed structure, composition, and geodynamic evolution. To shed light on these complexities, we leverage the ambient noise tomography (ANT) method to invert shear wave velocity (Vs) and image subsurface structures, providing crucial insights into both subsurface geology and deep crustal processes. Specifically, we employed two different methods: Markov chain Monte Carlo (MCMC) and Evolutionary Algorithm (EA) inversions to robustly constrain the Vs velocity structure, Vp/Vs ratio, and density beneath the CVL and its surrounding area.Our results reveal a prominent high-velocity structure at depths of 25 to 35 km, which precisely aligns with the CVL. Within this region, Vs velocities reach up to 4.0 km/s, accompanied by a Vp/Vs ratio ranging between 1.85 and 1.88 and density varying from 2.9 to 3.1 g/cm3. These characteristics suggest the presence of cooled mafic material that has intruded the crust. Our 2D depth cross-sections along the CVL indicate that these cooled mafic intrusions are ubiquitous along the entire volcanic line. However, they are spatially separated from the upper crust's volcano-plutonic structure by a thin intermediate structure exhibiting a Vp/Vs ratio of 1.68 to 1.71 and an average Vs velocity of 3.8 km/s, indicative of felsic to intermediate crust, which may be linked to the Pan-African Orogeny.The high Vp/Vs ratio and Vs velocity structures are found closer to the surface in the recently active volcanic provinces, accompanied by a thinner low Vp/Vs structure. We posit that this thinned low Vp/Vs structure may have facilitated the ascent of mafic material, contributing to recent volcanic activity in the region. Conversely, beneath the Oubanguides belt and Congo craton, these low Vp/Vs structures appear thicker, with mafic intrusions present at depth > 35 km. This observation suggests a dynamic process involving the pushing and exhumation of lower crustal material by the mafic material.Our crustal imaging results hold significant implications for our understanding of the region's geodynamic evolution, suggesting an interaction with deeper structures, may be responsible for the crustal intrusions and volcanism observed along the CVL.