Basin Research - Volume 34, Issue 1, 2022

A seismic data led approach to modelling subsurface temperatures in offshore basins.

The North Viking Graben (NVG) is part of the mature North Sea Basin petroleum province and designated as a major carbon storage basin for NW Europe. It has been extensively drilled over five decades with an abundance of well and seismic data in the public domain. As such it serves as an excellent setting to demonstrate the efficacy of a reflection seismic data led approach to predicting subsurface temperatures using a state‐of‐the‐art, full‐waveform inversion velocity model covering the entire NVG. In a forward modelling approach, an empirical velocity to thermal conductivity transform is used in conjunction with predefined heatflow to predict subsurface temperature. The predefined heatflow parameters are set based on the range of values from previous studies in the area. Abundant well data with bottom hole temperature (BHT) records provide calibration of results. In the second step of inverse modelling, BHTs and the velocity derived thermal conductivity are used to derive heat flow based on a 1D steady‐state approximation of Fourier's law. In this way, heatflow is estimated over the 12,000 km² model area at a km scale (lateral) resolution, highlighting lateral variability in comparison with the traditional point‐based heatflow data sets. This heatflow is used to condition a final iterative loop of forward modelling to produce a temperature model that is best representative of the subsurface temperature. Calibration against 139 exploration wells indicate that the predicted temperatures are on average 0.6℃ warmer than the recorded values. BHT for the recently completed Northern Lights carbon sequestration 31/5‐7 (Eos) modelled to be 97℃, which is 6℃ below the recorded BHT. This highlights the applicability of this workflow not only towards enhancing petroleum systems modelling work but also for use in the energy transition and for fundamental scientific purposes.

Schematic illustration of the tectono‐stratigraphic evolution of the offshore western Niger Delta from the Cretaceous to the Present. (a) Development of duplexes within the upper detachment unit; (b) initiation of gravity‐driven deformation within the currently active extensional and translational zones; (c) coupling of deformation between the extensional and translational zones, and inferred progradation of the ‘Oligocene‐Tortonian extensional zone’; (d) acceleration of gravity‐collapse of the continental shelf, and initiation of deformation within the outer fold‐thrust belt (OFTB); (e) intensification of gravity collapse and deformation at the leading front of the OFTB. (a, b) Line drawing, showing the stratigraphic architecture of the offshore eastern Niger Delta lobe (ENDL) (after Jermannaud et al., 2010) and western Niger Delta lobe (WNDL). Note: (i) Overall progradation during the late and early Pliocene, in the ENDL and WNDL; (ii) retrogradation and sediment storage on shelf of the ENDL in the Pleistocene, compared to progradation and sediment bypass on the shelf of WNDL during the Pleistocene.

The interaction between sedimentary wedge dynamics and paleo‐fracture zones is investigated offshore western Niger Delta lobe (WNDL) to reconstruct the evolution of the delta from the Cretaceous to present. This was achieved through detailed regional seismic interpretation, calibrated with well data. Our results suggest that high sedimentation rates in the WNDL since the Serravallian–Tortonian triggered the migration of the ‘Oligocene‐Tortonian extensional zone’ and gravity spreading seawards (from a present‐day onshore to a present‐day offshore position), with extensional, translational and contractional deformation. An additional increase in sedimentation rate since the early Pliocene, further accelerated gravity spreading and the development of the present‐day contractional front. A five‐stage tectono‐stratigraphic evolution of the offshore WNDL from the late Cretaceous to present is proposed. Paleo‐topographies formed by the Charcot and Chain Fracture Zones exerted depositional control on the stratigraphic architecture of the offshore WNDL from the Cretaceous to Serravallian. Differential subsidence on both sides of the relict Charcot and Chain transform faults is responsible for the segmentation of gravity‐driven deformation of the eastern and western Niger Delta lobes. In addition, a comparison of the stratigraphic architecture of the eastern Niger Delta lobe (ENDL) and WNDL demonstrates a similar overall progradation and sediment bypass to the deep basin during the Pliocene. During the Pleistocene, the two lobes show a distinct evolution and architecture: the ENDL shows an overall retrogradation and sediment sequestration on the shelf, whereas the WNDL displays an overall progradation and sediment bypass. This study documents long‐term and large‐scale control of delta dynamics and paleo‐topography on gravity‐driven deformation of the offshore eastern and western Niger Delta lobes, and similar analysis could be applied in the reconstruction of other passive margin basins.

During the Messinian Salinity Crisis (MSC, 5.97–5.33 Ma), thick evaporites were deposited in the Mediterranean Sea associated with major margin erosion. This has been interpreted by most authors as resulting from water level drop by evaporation but its timing, amplitude and variations between subbasins are poorly constrained due to uncertainty in post‐Messinian vertical motions and lack of a clear time‐correlation between the marginal basin and offshore records. The Balearic Promontory and surrounding basins exemplify a range of responses to this event, from margin erosion to up to a kilometre thick Messinian units in the abyssal areas containing the majority of the MSC halite. The Balearic Promontory contains unique patches of halite with thickness up to 325 m at intermediate depths that provide valuable information on water level during the stage of halite deposition. We compile seismic markers potentially indicating ancient shorelines during the drawdown phase: the first is marked by the transition from the MES to UU based on seismic data. The second is the limit between the bottom erosion surface (BES) and abyssal halite deposits. We restore these shorelines to their original depth accounting for flexural isostasy and sediment compaction. The best‐fitting scenario involves a water level drop of ca. 1,100 ± 100 m for the Upper unit level and 1,500 ± 100 m for the BES level. According to our results, halite deposition began in the Central Mallorca Depression at 1,300–1,500 m depth, perched hundreds of metres above the deep basins, which were at 1,500–1,800 m (Valencia Basin) and >2,900 m (Algerian Basin). The hypothesis that erosion surfaces were formed subaerially during the drawdown phase is consistent with a model of halite deposition before/during the water level drop of at least 1,000 m, followed by the deposition of the Upper unit until the MSC is terminated by the reinstatement of normal marine conditions.

Erosional surfaces and deposits linked to the Messinian Salinity Crisis are restored to their original depth by planform flexural‐isostatic backstripping. A large seismic dataset covering the Western Mediterranean is used to constrain the current depth of Messinian markers, and by matching the water level to interpreted shoreline markers at the bottom erosion surface and the Upper unit limit we estimate possible water level at different moments during the Messinian Salinity Crisis.

Submarine landslides associated with the Cascadia subduction zone offshore of the Pacific northwest United States and Canada represent significant natural geohazards. Mapping past submarine landslide deposits is critical for understanding present and future slope failure and tsunami hazard potential. We focus on the portion of Cascadia offshore Oregon to map the occurrences of submarine landslide deposits (mass transport deposits [MTDs]) in the subsurface using recent high‐resolution reflection seismic data. We identified 133 MTDs and categorized them based on their present morphology inferred from their acoustic characteristics as disintegrative or blocky. Interestingly, nearly 76% of the MTDs are located in the northern Oregon margin and many of these are non‐cohesive disintegrative deposits. MTDs are less common in the southern Oregon margin, however, they were also much larger and more cohesive than those found in the north. The differences are not likely to be related to differences in earthquake intensity but rather sedimentation rates and basin structures. Specifically, the northern Oregon margin is proximal to the sediment‐delivery systems of the Columbia River and has landward verging fold‐and‐thrust structures, whereas the southern Oregon margin is relatively sediment starved and has seaward verging structures resulting in fewer steep ridges. Because of the higher sedimentation rates, the northern Oregon margin may be prone to more frequent and disintegrative types of slope failures. In contrast, the southern margin may have enhanced slope stability due to seismic strengthening and lower sedimentation rates. However, when slope failures do occur in the southern Oregon margin, they tend to be more cohesive and blocky. Therefore, even though there are fewer slope failures in the southern Oregon margin, there is still hazard potential because fast‐moving cohesive slope failures can generate tsunami.

Mapping past submarine landslide deposits is critical in understanding present and future slope stability and its associated tsunami hazard potential. Here we focus on the offshore Oregon portion of the Cascadia margin to map the spatial distribution of subsurface mass transport deposits (MTDs) offshore Oregon. MTDs plotted here are medium and high confidence and color‐coded by type (blocky (blue squares), disintegrative (yellow circles) or slump (red diamond)) along strike of the margin (latitude) and with time (depth). Both margins are dominated by disintegrative MTDs, however, the south has a higher percentage of blocky MTDs than the south. Even though there are fewer MTDs in the southern Oregon margin, there is still significant hazard potential because fast‐moving cohesive slope failures can generate tsunami.

Mud volcano plumbing systems and dissolution structures present novel kinematic markers during salt tectonic deformation. The offset of their genetically connected pre‐salt and post‐salt components records the translation direction, distance, average velocity and allows the salt flow regime to be inferred. The widespread distribution of these kinematic markers in the Western Nile provides calibration of salt flow over an area > 3000 km². Mud volcano systems and dissolution structures can be added to deformed fluid escape pipes, salt‐detached ramp syncline basins and deformed intra‐salt structures as part of a growing suite of kinematic markers for reconstructing salt flow.

The recognition of linear trails of fluid escape pipes that have been deformed by salt flow have recently been suggested to offer a novel approach to reconstructing the internal kinematics of thick salt sequences deforming under gravity. These deformed pipes constrain a number of key parameters for salt tectonic analysis including the salt flow direction, translation distance of the top salt and overburden, the internal flow profile and from the flow velocity, the bulk viscosity of the salt. Here we interpret and characterise two previously unrecognised large‐scale strain markers within a salt sequence that may be equally as valuable as the deformed pipes for constraining salt flow. This study is based on the interpretation of a ca. 4,600 km² 3D seismic survey from the outer slope of the Nile Cone, offshore Egypt, located at the boundary between the extensional and translational domains of the deformed marginal region of the Messinian salt basin. We mapped five deformed pipe trails that allow us to constrain the average flow velocity of the top salt, at ca. 2 mm/yr over the past 2–3 Myrs. The salt flowed in a basinward NW/NNW direction away from the basin margin. In addition, we mapped two large (ca. 2 km diameter) salt dissolution depressions formed by subjacent dissolution of the evaporites. These are presently located down the salt flow direction of a large remnant erosional high at the base of the salt, and in the general alignment of one of the pipe trails. We therefore argue that this dissolution structure most likely formed by fluid venting from the base salt high, and as such can be used to measure translation direction, distance and average velocity. The second of the two novel kinematic indicators requires mapping of genetically connected mud volcanoes and their depletion zones. The study area contains over 400 individual mud volcanoes that are sourced from beneath the salt and erupted from the Early Pliocene to Recent. A subset of these, extruded at or near to the present day seafloor, have well imaged pre‐salt depletion zones vertically beneath the erupted volcanic cones. A smaller subset, typically buried Early Pliocene extrusions, is found to have volcanic cones that are systematically offset laterally from their corresponding depletion zones, with an offset direction and distances closely matched with other kinematic markers. Hence we suggest that mud volcanic plumbing systems can provide another independent kinematic marker from which to infer salt flow regime.

Continental rifting is accommodated by the development of normal fault networks. Fault growth patterns control their related seismic hazards, and the tectonostratigraphic evolution and resource and CO2 storage potential of rifts. Our understanding of fault evolution is largely derived by observing the final geometry and displacement (D)‐length (L) characteristics of active and inactive fault arrays, and by subsequently inferring their kinematics. We can rarely determine how these geometric properties change through time, and how the growth of individual fault arrays relate to the temporal evolution of their host networks. Here we use 3D seismic reflection and borehole data from the Exmouth Plateau, NW Shelf, Australia to determine the growth of rift‐related, crustal‐scale fault arrays and networks over geological timescales (>10⁶ Ma). The excellent‐quality seismic data allows us to reconstruct the entire Jurassic‐to‐Early Cretaceous fault network over a relatively large area (ca. 1,200 km²). We find that fault trace lengths were established early, within the first ca. 7.2 Myr of rifting, and that along‐strike migration of throw maxima towards the centre of individual fault arrays occurred after ca. 28.5 Myr of rifting. Faults located in stress shadows become inactive and appear under‐displaced relative to adjacent larger faults, onto which strain localises as rifting proceeds. This implies that the scatter frequently observed in D‐L plots can simply reflect fault growth and network maturity. We show that by studying complete rift‐related normal networks, rather than just individual fault arrays, we can better understand how faults grow and more generally how continental lithosphere deforms as it stretches.

The three stages of fault network evolution are (A) Initiation, (B) Interaction, and (C) Through‐going zones. We expand on this model by presenting a schematic evolution (1–5) that aims to honour kinematic and geometric constraints imposed by D‐L observations, and the recognition of stress feedback between fault arrays.

Thermokinematic models of balanced cross‐sections integrated with bedrock cooling ages and basin thickness and depositional ages are presented for Arunachal Pradesh, NE India. Model results demonstrate that the location and timing of rock uplift and exhumation (cooling) is largely controlled by the kinematic sequence and shortening rate. Measured bedrock cooling ages and basin constraints are best fit by models with a kinematic sequence involving early foreland propagation combined with variable shortening rates.

Quantitative integration of cross‐section geometry, kinematics and cooling ages requires notably more complicated kinematic and exhumation pathways than are typically assumed with a simple in‐sequence model of cross‐section deformation. Incorporating measured basin thickness and depositional ages, determined from magnetostratigraphy or young detrital zircon fission track cooling ages, provide further constraints on the timing of fault motion, as changes in shortening rate that may not alter bedrock cooling ages can affect the depositional age of foreland basin strata. Thermokinematic models of balanced cross‐sections in Arunachal Pradesh, NE India demonstrate that the kinematic sequence and shortening rate exert the largest control over the pattern of predicted cooling ages for the region, by dictating the location and timing of rock uplift and exhumation (cooling) over ramps. The best fit to the measured bedrock cooling ages and basin constraints is achieved with a kinematic sequence involving early foreland propagation of four Lesser Himalayan faults combined with variable shortening rates. Fast rates (25–30 mm/yr) are required to accompany early foreland propagation at ca. 14–13 Ma followed by slower rates (18–20 mm/yr) until 10 Ma. Shortening rates increase to ca. 25–35 mm/yr at ca. 10 Ma until ca. 5–7 Ma. A decrease in shortening rate occurs between 7 and 5 Ma, with rates of 9–15 mm/yr until the present. Although non‐unique, the updated cross‐section geometry and kinematics highlight the components of geometry, deformation and exhumation that must be included in any valid cross‐section model for this portion of the eastern Himalaya such as the location of active ramps, and location and age of two key fault systems, the Bomdila imbricate zone and the thrust faults that form the Lumla duplex. Less unique are the specific geometries of faults, thickness of strata they carry, shortening rates, particularly between 14–8 Ma, and model parameters such as topography, heat production and flexure.

Integrating bedrock and detrital cooling ages with thermokinematic models of sequential deformation of a balanced cross‐section reveals spatial and temporal variations in exhumation rates in Arunachal Pradesh, NE India. Predicted detrital apatite fission track ages record a constant lag time, while predicted detrital zircon fission track ages record changes in lag time as a function of the kinematics, deformation rates, and thermal profile of the crust in the source region.

The exhumation record of a fold‐thrust belt is preserved by thermochronologic minerals, such as zircon and apatite, both in exposed bedrock and in synorogenic sedimentary rocks in the foreland basin. Treating these as separate records can lead to potentially contrasting interpretations of a single exhumation history. Integrating the bedrock and detrital records with thermokinematic models of sequential deformation of a fold‐thrust belt can identify viable exhumation pathways of the bedrock and elucidate both how bedrock exhumation varies in space and time and how accurately the basin records exhumation changes in the source region. Predicted bedrock cooling ages and modelled basin thickness are used to estimate the amount and source of sediments supplied to the foreland basin during each increment of deformation to predict the detrital cooling signal over time. Applying this integrated bedrock‐detrital model to a cross‐section in Arunachal Pradesh, NE India demonstrates spatial and temporal variability in exhumation, with a background exhumation rate of <2 mm/yr, periods of rapid exhumation at rates of 3–7 mm/yr, and short pulses of 10–12 mm/yr rates during out‐of‐sequence thrusting. Our results predict that the detrital apatite fission track (DAFT) system records a constant lag time of 0.5–1 Myr. Although the response of the detrital zircon fission track (DZFT) system is more complex, the system records changes in lag time (1–5 Myr) as a function of the kinematics, deformation rates and thermal profile of the crust in the hinterland. However, the DZFT cooling signal is delayed by 1–2 Myr relative to the age of marked shifts in location, magnitude and rate of exhumation in the source region. Our models also highlight the importance of recycled foreland deposits in matching the ca. 20 Ma static peak in the DZFT record and ca. 14 Ma static peak in the DAFT record.

A three‐stage structural model for development of the Xuanhua basin during Late Jruassic‐Early Cretaceous (161‐136 Ma). Piggyback progradation of the Xiahuayuan thrust fault system (faults F7, F9, and F11) controlled this period of basin‐filling processes and the formation of two large‐scale upward‐coarsening successions, which represent syn‐tectonic sedimentation of thrusting events.

Arguments for recognizing autogenic vs. allogenic signals in the stratigraphic record are still far from settled, as is the decoding of unsteady allogenic responses to climate vs. tectonic forcing. We offer the case of late Mesozoic Xuanhua basin in the western Yanshan fold‐and‐thrust belt of North China to make these points. The study area is an intramontane basin that has allowed detailed structural, sedimentological, and provenance analyses in a kilometre‐thick succession (the Tuchengzi Formation) of alluvial fan, fluvial, lake‐delta and lacustrine deposits. Extensive geological mapping provided confidence of near‐basinwide later correlation of strata, revealing two large‐scale upward‐coarsening (CU) successions each 80–240 m thick, with prominent vertical changes from lacustrine through deltaic and fluvial to alluvial fan deposits. Two intervals of thrust‐related growth strata identified in the Tuchengzi Fm suggest that the CU successions were the signals of tectonic uplift and accommodation change related to Likouquan and the Mapu thrusting. In the lower CU succession, there is a stacking (30+) of small‐scale (3–16 m thick) upward‐fining cyclothems that are argued to have been generated by alternating wet‐dry climate cycles. The wet half‐cycle is argued to have initiated with high sediment and water discharge of flood‐generated mass flows into the lake and ended with accumulation of lacustrine mudstones as lake level rose. The lake deposits include the maximum flooding during the wet half‐cycle. The dry half‐cycle was characterized by continued lacustrine deposits, but increased evidence of subaerial exposure (rooting, paleosols, and mudcracks) argued to result from falling of the lake level under dry conditions.

In the Baltic sector of the North German Basin, minor salt movement started comremporaneous with Late Cretaceous inversion in the Coniacian‐Santonian and lasted until the end of the Late Cretaceous. A late Paleocene to middle Eocene phase of tectonic quiescense was followed by recommencing major salt movement in the Glückstadt Graben in the Late Eocene‐Oligocene. This Cenozoic phase of salt structure growth critically exceeded salt flow during the Late Cretaceous inversion and is likely controlled by thin‐skinned extension, possibly related to the beginning development of the European Cenozoic Rift System.

The Late Cretaceous to Cenozoic is known for its multiple inversion events, which affected Central Europe's intracontinental sedimentary basins. Based on a 2D seismic profile network imaging the basin fill without gaps from the base Zechstein to the seafloor, we investigate the nature and impact of these inversion events on Zechstein salt structures in the Baltic sector of the North German Basin. These insights improve the understanding of salt structure evolution in the region and are of interest for any type of subsurface usage. We link stratigraphic interpretation to previous studies and nearby wells and present key seismic depth sections and thickness maps with a new stratigraphic subdivision for the Upper Cretaceous and Cenozoic covering the eastern Glückstadt Graben and the Bays of Kiel and Mecklenburg. Time‐depth conversion is based on velocity information derived from refraction travel‐time tomography. Our results show that minor salt movement in the eastern Glückstadt Graben and in the Bay of Mecklenburg started contemporaneous with Late Cretaceous inversion in the Coniacian‐Santonian. Minor salt movement continued until the end of the Late Cretaceous. Overlying upper Paleocene and lower Eocene deposits show constant thickness without indications for salt movement suggesting a phase of tectonic quiescence from the late Paleocene to middle Eocene. In the late Eocene to Oligocene, major salt movement recommenced in the eastern Glückstadt Graben. In the Bays of Kiel and Mecklenburg, late Neogene uplift removed much of the Eocene‐Miocene succession. Preserved deposits indicate major post‐middle Eocene salt movement, which likely occurred coeval with the revived activity in the Glückstadt Graben. Cenozoic salt structure growth critically exceeded salt flow during Late Cretaceous inversion. Cenozoic salt movement could have been triggered by Alpine/Pyrenean‐controlled thin‐skinned compression, but is more likely controlled by thin‐skinned extension, possibly related to the beginning development of the European Cenozoic Rift System.

Sediment transport through the Mississippi River affects the lives and economies of millions of people along its course, so that understanding the controls on this process is of scientific and societal importance. Detrital U‐Pb geochronology, supported by grain size and major element data, can be a robust tool for constraining sediment provenance in clastic sedimentary systems that has been applied to the Mississippi. However, sediment storage and reworking can complicate interpretation, and this can be further exacerbated by anthropogenic alteration via the construction of levees, dams, locks and river diversion projects. In this study, we date zircons from the modern Mississippi River and compare them to previously acquired data to illustrate the difference between samples taken from the same catchment in order to better understand the downstream propagation of the modern detrital zircon signal. The modern Mississippi River and tributary systems show distinct similarities and are comparable between studies when samples are not too far separated (<100 km). We estimate that the Arkansas River is more important than previously proposed, at least in terms of sand supply, supplying 7%–11% of the total load. The largest supplier of sediment to the Mississippi is the Missouri River (33%–43%), which derives much of its sediment from sedimentary rocks in the foredeep deposited during the Sevier and Laramide events. Anthropogenic alteration of the modern river system can be seen in the downstream propagation of a Red River cut‐off signal following construction of the “River Control Structure”, implying slow zircon transport rates (<2.8 km/year). Differences in the degree of recycling caused by sampling locations and low numbers of grains introduce significant uncertainties to mixing calculations.

Pie plots showing the evolving composition of the Mississippi along its major course with contributions from the dominant tectonic blocks of North America defined by the age of the zircons in the tributaries and the main stream. Note the large amount of 30–275 Ma grains reaching the ocean and that are largely derived from the Missouri River.

The US Appalachian Basin and the Arctic Norwegian and Russian Barents Sea shelf (BSS) areas are two strategic provinces for the energy industry. The Appalachian Basin is a well‐studied, mature, onshore basin, whereas the offshore BSS is still considered a frontier area. This study suggests that the Appalachian Basin may be an appropriate analogue for understanding the BSS and contribute to development of a tectonostratigraphic framework for the area. Although the Appalachian and BSS areas reflect different times and settings, both areas began as passive margins that were subsequently subjected to subduction and continent collision associated with the closure of an adjacent ocean basin. As a result, both areas exhibited multi‐phase subduction‐type orogenies, a rising hinterland that sourced sediments, and a foreland‐basin sedimentary system that periodically overflowed onto an adjacent intracratonic area of basins and platforms with underlying basement structures. Foreland‐basin sedimentary systems in the Mid‐to‐Late Palaeozoic Appalachian Basin are composed of unconformity‐bound cycles related to specific orogenic pulses called tectophases. Each tectophase gave rise to a distinct sequence of lithologies related to flexural events in the orogen. In this study, similar sequences are recognised in both BSS foreland‐basin and adjacent intracratonic sedimentary sequences that formed in response to the Late Palaeozoic–Mesozoic Uralian–Pai–Khoi–Novaya Zemlya Orogeny, suggesting that the processes generating the sequences are analogous to the tectophase cycles in the Appalachian Basin. Hence, this pioneering use of the Appalachian area and its succession as large‐scale tectonostratigraphic analogues for the BSS may further enhance understanding of Upper Palaeozoic to Middle Jurassic stratigraphy across the BSS.

Model A shows diagnostic features of the Acadian/Neoacadian Appalachian tectonostratigraphic setting, used in the paper as a standard analogue for interpreting the target, Uralian‐Pai‐Khoi‐Novaya Zemlya tectonostratigraphic setting on the Barents Sea shelf (Model B).

Well‐developed clastic shoreline systems have been deposited in the Gippsland Basin over a 70 Ma period, from the latest Cretaceous to the present day. Twenty‐three stacked coastal units have been mapped and described in the Traralgon and Balook formations of the Latrobe and Seaspray groups. These units are made up of prograding and backstepping shoreface deposits, which, in plan view, display well‐developed strandline geometries at the terrestrial–marine interface. Shoreface deposits are interpreted to include prograding beach, barrier island and transgressive beach deposits. The lower coastal plain is characterised by persistent deposition of coals despite changes in shoreface type and significant palaeoclimate fluctuations. These coastal deposits display approximately 123 km of transgression from the Late Cretaceous shoreline at the base of the study interval to the mid Miocene Yallourn Formation near the top. The Late Cretaceous and Palaeocene shoreline deposits individually prograde and are separated by flooding surfaces reflecting eustatic changes. Overall they display long‐term backstepping behaviour (retrogradation) as a result of basin subsidence. Though shorelines of the Eocene–Miocene are distinctly transgressional, probably reflecting basin subsidence, in the mid‐Miocene they become individually and collectively progradational. A series of unconformities in the Oligocene, coupled with Miocene progradation, likely reflects a combination of a compressional tectonic regime and glacioeustatic fluctuations. Despite major changes in the tectonics and palaeoclimate, basin subsidence appears to be the dominant driver for changes in shoreline location.

The Late Cretaceous to Miocene interval of the Gippsland Basin is composed of 23 stacked coastal plain‐shoreface units. Shorefaces are predominantly retrogradational, only becoming regressive in the Oligocene, likely as a result of compressional tectonics and global icehouse conditions. Despite changes in paleoclimate, ocean chemistry and tectonics, depositional environments remain relatively consistent over 70 Ma.

Main steps/findings of sequential restoration:

1. Fault movement is restored
2. Estimation of eroded volume (Cir‐01 profile)
3. Restoration of local erosion (p607 profile)
4. Removing the top unit and decompaction lower units
5. Restore folded unit to its original (supposed) geometry

Tectono‐stratigraphic interpretation and sequential restoration modelling was performed over two high‐resolution seismic profiles crossing the Western Ionian Basin of southern Italy. This analysis was undertaken in order to provide greater insights and a more reliable assessment of the deformation rate affecting the area. Offshore seismic profiling illuminates the sub‐seafloor setting where a belt of active normal faults slice across the foot of the Malta Escarpment, a regional‐scale structural boundary inherited from the Permo‐Triassic palaeotectonic setting. A sequential restoration workflow was established to back‐deform the entire investigated sector with the primary aim of analysing the deformation history of the three major normal faults affecting the area. Restoration of the tectono‐stratigraphic model reveals how deformation rates evolved through time. In the early stage, the studied area experienced a significant deformation with the horizontal component prevailing over the vertical element. In this context, the three major faults contribute to only one third of the total deformation. The overall throw and extension then notably reduced through time towards the present day and, since the middle Pliocene, ongoing crustal deformation is accommodated almost entirely by the three major normal faults. Unloading and decompaction indicate that when compared to the unrestored seismic sections, a revision and a reduction of roughly one third of the vertical displacement of the faults offset is required. This analysis ultimately allows us to better understand the seismic potential of the region.

(a) Seismic reflection profile across the Taiepa Nui Basin and high illustrating syn‐rift seismic facies filling the basin. See Figure 1b and XY on Figures 1b, 4a and 6b for location. (b) Results of the modelling of drainage on the top basement isochron using the Hydro Terrain Processing Tool of ArcGIS software and the base map of Sahoo et al. (GNS Science Data Series 23c 1, 2017).

The Canterbury Basin in southeastern Zealandia was initiated during the late Albian (ca. 105 Ma) as a rift system, prior to the onset of seafloor spreading between Zealandia and eastern Gondwana at ca. 85 Ma. Basin‐fill architecture and sediment types have been determined from interpretation of 2D and 3D seismic‐reflection lines tied to five wells and compared to outcrop data from the literature. These data show that Cretaceous syn‐rift basin‐fill architecture was controlled by normal faulting, which produced basin and range topography that persisted for more that ca. 30 Myr after the cessation of faulting. Initial sedimentation was dominated by short drainage systems sourced from within the basin to produce alluvial fans along fault scarps, which inter‐fingered with axial‐flowing braided river conglomerates, coal measures and mudstone‐rich lake deposits in more central portions of the basins. Marine incursion of the basin from the east commenced during rifting and onset of Gondwana breakup, with maximum water depths achieved in the Oligocene. Post‐rifting, detrital sediments were mainly sourced locally from structural highs and augmented by pelagic sedimentation, which collectively draped and eventually buried most of the earlier‐formed horsts by the Early Eocene. The temporal persistence of basin and range topography reflected the low rates of erosion of horst blocks compared to the rates of fault displacement. The lack of substantial sediment input from outside of the rift basin was a key factor in the under‐filling of the Canterbury Basin. This research emphasises the key role played by sediment supply in rift basin filling. Despite an abundance of active faulting at initiation, some rift basins may fill slowly over tens of million years after rift cessation.

Block diagram showing paleogeographic reconstruction of the greater Green River Basin. (a) During the deposition of the Hams Fork member of the Evanston Formation and upper Almond Member of the Mesaverde Formation (early Maastrichtian, ca. 71 Ma). (b) During the deposition of the Canyon Creek member of the Ericson Formation (late Campanian, ca. 73 Ma). Boundary of coastal plain and location of shoreline in Colorado referenced from López and Steel (2015). Cross section view modified from Yonkee and Weil (2015).

Three drivers of subsidence are recognized in the Western Interior Basin: Mesozoic–early Cenozoic flexure adjacent to the thin‐skinned, eastward propagating Sevier Orogeny, Late Cretaceous–Eocene flexure associated with thick‐skinned Laramide Uplifts and Late Cretaceous dynamic subsidence. This study combines outcrop lithofacies, palaeocurrent measurements, detrital zircon geochronology, biostratigraphy, stratigraphic correlations and isopach maps of Coniacian–Maastrichtian (89–66 Ma) units to identify these subsidence mechanisms impact on basin geometry and stratigraphic architecture in the northern Utah to southwestern Wyoming segment of the North American Cordillera. Detrital zircon maximum depositional ages and biostratigraphy support that the Maastrichtian Hams Fork Conglomerate was deposited above the Moxa unconformity in the wedgetop and foredeep depozones. The Moxa unconformity underlies the progradational Ericson Formation in the distal foredeep. The Hams Fork, however, is younger than the Ericson Formation, and instead equivalent to upper Almond Formation. Therefore, the hiatus associated with the Moxa unconformity continued for several million years longer in the fold belt and proximal basin than in the distal foredeep, with Ericson Formation‐equivalent strata onlapping the Moxa unconformity towards the west. Regional thickness patterns record and constrain the timing of the transition from Sevier to Laramide‐style tectonic regimes. From 88 to 83 Ma (upper Baxter Formation) a westward‐thickening stratigraphic wedge characterized the foredeep developed by lithospheric flexure by thrust‐belt loading. Nevertheless, the presence of >500 m of subsidence >200 km from the thrust front suggests a long‐wavelength subsidence mechanism consistent with dynamic subsidence. By 83 Ma (Blair Formation) the long‐wavelength depocentre shifted away from the thrust belt, with no evidence of a Sevier foredeep. This depocentre continued migrating eastward during the early‐mid Campanian (ca. 81–77 Ma). The late Campanian–Maastrichtian (ca. 74–66 Ma) is marked by narrow sedimentary wedges adjacent to the Wind River, Granite and Uinta Mountain uplifts and attributed to flexural loading by Laramide deformation.

Source‐to‐sink studies and calculating sediment budgets of ancient systems are important approaches for basin analysis. Because of the enormous scale of basins, most existing studies depend on subsurface datasets. As drilling campaigns focus on structural highs or specific trap types, well datasets cover only limited subareas of entire sedimentary basins. Outcrop studies are almost always based on even more spatially limited datasets. The ramifications for basin analysis are considerable: (1) actual sediment budgets are underestimated; (2) catchment denudation rates and sizes are miscalculated; (3) predicted net:gross ratios in sink areas bear high uncertainties. This paper outlines a new workflow‐defined approach to reconstruct regional grain size profiles to better estimate sediment budgets across an entire sedimentary basin, even when datasets have spatial limited coverage. The workflow includes compilation of grain size data, transformation to mass balance frameworks, and lateral matching of local to regional grain size profiles. The approach was tested on two representative continental‐to‐marine delta systems which are covered by four spatially limited datasets while the entire sedimentary basin (sink area) is much larger. The original estimates account for only maximum 40% of the actual total sediment volume as analysed with the new approach. The new method provides significantly improved constraints for catchment (source) models as well as input parameters (sediment budget, input locations, fractions) for process‐based depositional modelling for predictions of net:gross and detailed facies proximal to distal relationships. General benefits include lower uncertainties in clastic reservoir quality prediction (hydrocarbon exploration) and provenance analysis (fundamental research).

Sediment budgets based on zircon ages (b), heavy minerals (c), integrated petrographic and heavy‐mineral datasets (d), and geochemistry (e) converge to suggest that the Lhasa Block contributes ~77% of the sand carried by the Yarlung Tsangpo in the middle reaches, and up to ~83% of the sand before draining into the Yarlung Tsangpo gorge (a).

The Yarlung Tsangpo, draining the Himalayan‐Tibetan orogen along the Indus‐Yarlung suture zone, receives detritus from the deformed remnants of both Indian margin to the south and Asian margin to the north. High resolution petrographic, heavy‐mineral and geochemical datasets, combined with published geochronological data, allow us to monitor compositional changes, estimate erosion rates and investigate lithologic, climatic and anthropic controls on sediment fluxes along this large sediment‐routing system entirely developed within high mountain areas. Sediment generated from the Lhasa Block along the southern margin of Asia is characterized by abundant feldspar and volcanic rock fragments, amphibole‐dominated transparent heavy mineral suite and high concentrations of K, Rb, Be, Th and Pb. Himalayan‐derived sand, instead, is characterized by sedimentary to low‐rank metasedimentary rock fragments, poor transparent heavy mineral suite dominated by durable recycled (zircon, tourmaline) or metamorphic minerals (chloritoid, garnet) and high Ca concentration. Sand from the ophiolitic suture is distinguished by serpentinite grains and mafic volcanic or metavolcanic detritus, transparent heavy mineral suite including olivine, Cr‐spinel, enstatite and clinopyroxene, and high Mg, Cr, Ni and low rare earth elements. Himalayan detritus is prominent in Yarlung Tsangpo upper reaches, whereas detritus from the Lhasa Block becomes progressively predominant in the middle and lower reaches. Provenance budgets based on integrated petrographic, heavy‐mineral and geochemical datasets indicate that ca. 83% of the detritus is supplied by the Lhasa Block and the rest mostly from the Himalaya (ca. 12%) and subordinately from the ophiolitic suture (5%). A low average erosion rate of ca. 0.06 mm/a was estimated for the Yarlung Tsangpo catchment upstream of the Namche Barwa syntaxis, which resulted from dry climate, relatively mild average relief and sediment storage in wide valley tracts of the middle and lower reaches. The decrease in sediment flux recorded in recent decades is mainly ascribed to growing human activities, which are becoming a prominent control on sediment generation and transportation even in the high‐mountain area of South Tibet.