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<jats:title>Abstract</jats:title><jats:p>Geological process models typically simulate a range of dynamic processes to evolve a base topography into a final two‐dimensional cross section or three‐dimensional geological scenario. In principle, process parameters may be updated to better align with observed geophysical or geological data. However, it is hard to find any process model realisations that fit all observations if data sets are complex and sparse in space or time because the simulations typically depend highly non‐linearly on base topography and dynamic parameters. As an alternative, geophysical probabilistic tomographic methods may be used to estimate the family of models of a target subsurface structure that are consistent both with information obtained from previous experiments and with new data (the Bayesian posterior probability distribution). However, this family seldom embodies geologically reasonable images. Here we show that the posterior distribution of tomographic images obtained from travel time data can be fully geological by injecting geological prior information into Bayesian inference and that we can do this near‐instantaneously by using trained mixture density networks (MDNs). We invoke two geological concepts as prior information about the possible depositional environment of an imaged target structure: a braided river system and a set of marine parasequences. Each concept is parameterised by the latent parameters of a generative adversarial network. Data from a target structure can then be used to infer the family of compatible latent parameter values using either geological concept using MDNs. Our near‐instantaneous MDN solutions closely resemble those found using relatively expensive Monte Carlo methods. We show that while the use of incorrect geological conceptual models provides significantly less accurate results, a classifier neural network can infer which geological conceptual model is most consistent with the data. It is thus demonstrated that even apparently barely related geophysical data may contain information about abstract geological concepts, and that geological conceptual models are key to creating reasonable images from geophysical data.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Nielsen and Balling (2022) studied the thermo‐tectonic history of the eastern North Sea Basin from inversion of temperature, vitrinite reflectance and apatite fission tracks in boreholes, and found no evidence of Neogene exhumation. This contrasts with previous studies that reported the removal of 500–950 m of Cenozoic sediments during Neogene exhumation, partly based on velocity‐depth data in the Upper Cretaceous—Danian Chalk Group. Their result led Nielsen and Balling (2022) to ‘question the accuracy and precision of the sonic velocity method’. We submit that the use of velocity‐depth data to measure exhumation is a reliable method, and that the interruption of Cenozoic burial in the eastern North Sea Basin by Neogene exhumation is a well‐established geological fact. We suggest that the failure of Balling and Nielsen (2022) to detect Neogene exhumation is diagnostic of problems with their own methods, rather than reflecting on the reliability of the sonic velocity method.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The Gulf of Mexico is an intraplate oceanic basin where rifting commenced in the Late Triassic, leading to drifting and ensuing oceanic accretion by Middle‐Late Jurassic, which ceased by the Early Cretaceous. Its tectonic evolution encompasses multiple rifting phases dominated by orthogonal extension, variable magmatism and salt deposition. This complex tectonic history is recorded within the rifted margins of the Gulf of Mexico, including along the eastern part of the basin, where considerable uncertainty remains regarding the tectonic evolution and resulting crustal configuration. This study presents new insights into the crustal types and an updated tectonic framework for the Florida margin. An integrated analysis of seismic and potential field data allows us to characterize the nature of the crust, which shows wide zones of hyperextended continental crust, seaward dipping reflection (SDR) packages, exhumed mantle and magmatic crust. Our results propose elements that could improve the plate model of the Gulf of Mexico, by accounting for the polyphase nature of rifting, the counter‐clockwise rotation of the Yucatan block and the observed increase in magmatic supply.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The equatorial margin of Brazil is an example of a rift margin with a complex landscape, dominated by an escarpment perpendicular to the continental margin, which testifies to an equally complex rift and post‐rift surface and tectonic evolution. This has been the focus of a long debate on the driving mechanism for post‐rift tectonics and on the amount of exhumation. This study contributes to this debate with new petrographic and thermochronologic data on 152 samples from three basins, Pará‐Maranhão, Barreirinhas and Ceará, on the offshore continental platform. Our detrital record goes back to the rift time at ca. 100 Ma ago and outlines three major evolutionary phases of a changing landscape: a rift phase, with the erosion of a moderate rift escarpment, a Late Cretaceous‐Palaeogene post‐rift phase of major drainage reorganization and significant vertical erosion and a Late Oligocene‐to‐Recent post‐rift phase of moderate vertical erosion and river headwater migration. We estimate that along the equatorial margin of Brazil, over a large onshore area, exhumation since the Late Cretaceous has totalled locally up to 2–2.5 km and since the late Oligocene did not exceed 1 km.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Messina Strait is a narrow fault‐bounded marine basin that separates the Calabrian peninsula from Sicily in southern Italy. It sits in a seismically active region where normal fault scarps and raised Quaternary marine terraces record ongoing extension driven by southeastward rollback of the Calabrian subduction zone. A review of published studies and new data shows that normal faults in the Messina Strait region define a conjugate relay zone where displacement is transferred along strike from NW‐dipping normal faults in the northeast (southern Calabria) to the SE‐dipping Messina‐Taormina normal fault in the southwest (offshore eastern Sicily). The narrow marine strait is a graben undergoing active subsidence within the relay zone, where pronounced curvature of normal faults results from large strain gradients and clockwise rotations related to fault interactions. Based on regional fault geometries and published age constraints, we infer that normal faults in southern Calabria migrated northwest while normal faults in NE Sicily migrated southeast during the past ca. 2–2.5 Myr. This pattern has resulted in tectonic narrowing of the strait through time by inward migration of facing normal faults and rapid mantle‐driven uplift.</jats:p>

<jats:title>Abstract</jats:title><jats:p>We investigated calcites and dolomites precipitated during burial diagenesis of the Upper Triassic (Norian) continental siliciclastics from sub‐surface reservoirs of the northern Paris Basin (Chaunoy Formation) that experienced a thermal maximum &gt;100°C during Late Cretaceous times. Relative carbonate precipitation timing was established via petrographic analyses. The diagenetic carbonates were further investigated by fluid inclusion and clumped isotope (Δ<jats:sub>47</jats:sub>) thermometry. The two thermometric datasets were interpreted by evaluating the possible occurrence of inclusion thermal reequilibration and Δ<jats:sub>47</jats:sub> solid‐state reordering, based on the known basin thermal history and the three existing Δ<jats:sub>47</jats:sub> reordering models. By considering the fluid inclusion and Δ<jats:sub>47</jats:sub> datasets obtained and the various Δ<jats:sub>47</jats:sub> reordering models, different carbonate precipitation scenarios, in terms of timing and parent fluid composition (δ<jats:sup>18</jats:sup>O<jats:sub>fluid</jats:sub>), were inferred. These results underline that in samples having experienced thermal maximum &gt;100°C, accuracy and interpretation of fluid inclusion and Δ<jats:sub>47</jats:sub> thermometry data (especially on calcite) may be biased by thermal reequilibration and solid‐state reordering. The results converge towards the need of jointly applying fluid inclusion and Δ<jats:sub>47</jats:sub> thermometry on the same carbonate phases to evaluate all the possible precipitation scenarios. The most likely carbonate precipitation scenarios, based on Δ<jats:sub>47</jats:sub> thermometry data, point at the precipitation of two calcite phases during Early to Late Jurassic times and of one dolomite phase during the Late Cretaceous. The parent fluids possibly were original formation waters of the Chaunoy Fm. that mixed with brines migrating from the East, where time equivalent evaporitic deposits occur. The proposed precipitation model for calcites and dolomites, involving different pulses of brine migration, and the dominance of calcite phases were not recorded by previous studies on the Upper Triassic units. These latter results may be of interest to evaluate the reservoir potential of the Chaunoy Fm. in this underexplored portion of the Paris Basin.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The recent article of Loreto et al. (2021) reported new stratigraphic and structural data of the Tyrrhenian backarc basin and used them to propose a new model of crustal architecture of the basin including oceanic sectors. However, we want to open a discussion on the inconsistencies between the interpreted tectonic structures, as well as the age of faults and the data observations. In particular, data analyses and interpretations of the authors do not fully support the structural and isopach maps and models presented. Furthermore, the authors have not discussed previous published data/interpretations on timing and structural style of the rifting of the region.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The smectite‐illite transition in shales due to subsidence, temperature changes and diagenesis influences many processes in a sedimentary basin that can contribute to overpressure build up like reducing the shale permeability. The smectite‐rich layers can form sealing barriers to fluid flows that will influence pore pressure prognosis for drilling campaigns, contribute to sealing caprocks for possible CO<jats:sub>2</jats:sub> storage and to sealing of plugging and abandonment wells. In this work, we have included the diagenetic smectite‐illite transition into a three‐dimensional pressure simulation model to simulate its effect on pressure build‐up due to reduced shale permeabilities over geological time scale. We have also tested effect of thermal history and potassium concentration on the process of smectite‐illite transition and the associated smectite‐illite correction on permeability. A new smectite‐illite correction has been introduced, to mimic how shale permeability will vary dependent on the smectite‐illite transition. Stochastic Monte Carlo simulations have been carried out to test the sensitivity of the new correction parameters. Finally, a 3D Monte Carlo pore pressure simulation with 1000 drawings has been carried out on a case study covering Skarv Field, and Dønna Terrace offshore Mid‐Norway. The simulated mean overpressures are in range with observed overpressures from exploration wells in the area for the Cretaceous sandy Lysing Formation and for the two Cretaceous Intra Lange Formation sandstones. The simulated smectite content versus depth is in line with published XRD dataset from wells. The corresponding modelled present‐day permeabilities for the shales including the smectite‐illite transition are two magnitudes higher than measured permeabilities on small samples in the laboratory using transient decay method. The measured permeabilities are in the range of 2.66·10<jats:sup>−18</jats:sup> to 3.94·10<jats:sup>−22</jats:sup> m<jats:sup>2</jats:sup> (2695 to 0.39 nD) for the North Sea database and represent the end members for shales‐permeabilities with the lowest values, since the small samples are selected with no or minor natural fractures. This work shows that by upscaling shale permeabilities from mm‐scale to km scale, natural fractures and sedimentary heterogeneities will increase the shale permeabilities with a factor of two and that by including permeability correction controlled by the smectite fraction, pressure ramp can be simulated due to diagenesis effect in shales.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The seafloor morphology reflects both past and on‐going sedimentary, oceanographic and tectonic processes. Vertical movement is one of the drivers responsible for reshaping the seafloor through forming steep flanks that decrease slope stability, favour landslides, change current paths, form minibasins and control the sediment deposition, distribution and geometry. Here, we make use of these interactions to derive vertical movements and constrain the active tectonic processes at the western termination of the upper Calabrian accretionary wedge from the integrated analysis of bathymetric, backscatter, surface attributes and high‐resolution reflection seismic data. Within this area, we identify two types of deformational features and mechanisms that affect the depositional, erosional and tectonic processes at different scales. These include the deviation of channels, landslide scars, mass transport deposits (MTDs), separated drifts, sediment waves, lineaments and offset seafloor structures. The first type (long‐wavelength uplift) is an uplifted 22‐km‐wide region, in which seismic onlap relationships and the dip of deep reflectors suggest long‐lasting but slow tectonic uplift affecting sedimentation, and the second type (short‐wavelength uplift) includes three narrow elongated structures and one circular dome encircling the first region of uplift. We interpret that the first type of uplift feature was caused by tectonic deformation, while the second type is interpreted as formed by the fast uplift, tilting and faulting of modern sediments caused by diapirism due to rapid sedimentation in response to the first tectonically driven uplift. The study provides insight into the complex interaction of tectonic and sedimentary processes in the upper Calabrian accretionary wedge.</jats:p>