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Continental passive margins and their hinterlands in the Atlantic realm have been the locus of many Low Temperature Thermochronology (LTT) and time-Temperature (t-T) modelling studies that evidence pre-, syn- and post-rift episodic km-scale exhumation and burial episodes. In this study, we integrate data from over 30 published LTT and t-T modelling studies from Morocco and its surroundings using a three-step workflow to obtain: (a) exhumation/burial rates, (b) erosion rates and (c) palaeoreconstructions of source-to-sink domains, between the Permian and the Present. Our synthesis of available t-T modelling results predicts high exhumation rates in the Anti-Atlas (0.1 km/Myr) during the Early to Middle Jurassic, and in the High Atlas (0.1 km/Myr) and Rif (up to 0.5 km/Myr) during the Neogene. These rates are comparable to values typical of rift flank, domal or structural uplifts settings. During the other investigated periods, exhumation rates in the Meseta, High-Atlas, Anti-Atlas and Reguibat shield are around 0.04 ± 0.02 km/Myr. Interpolation of the exhumation rates at the regional scale allow calculation of the volume of rocks eroded. Estimates of erosion rates are between 0.2 x 103 and 7.5 x 103 km3 (in the Meseta and the Reguibat Shield respectively). Ten erosional (quantitative, from interpolation results) and depositional (qualitative, from data synthesis) "source-and-sink" maps have been constructed, with emphasis on the Jurassic and Cretaceous periods. The maps integrate the extent of exhumed domains, using information from geological maps, lithofacies and biostratigraphic data from new geological fieldwork and well data from onshore and offshore basins. The results illustrate changes in the sourceto-sink systems and allow for a better understanding of the Central Atlantic margin hinterlands evolution. [ABSTRACT FROM AUTHOR]

Crustal rheology and surface processes strongly influence strain distribution and shape of orogenic wedges at their front but how they influence the wedge rear is still unclear. Here, we analyse the coupled control of viscosity and sedimentation on forearc high growth during advanced stages of subduction accretion. We use 2D thermo-mechanical finite element models constrained with data of the south Anatolian margin. Our simulations show that forearc highs grow as a thermallyactivated viscosity drop in the lower crust induces ductile deformation and viscous flow. Initial viscosity and the amount of sediments in the forearc basin control nonlinearly the occurrence and timing of the thermally-activated viscosity drop, and thus of the growth of the forearc high. High sedimentation rates result in thicker forearc basins that stabilise the subduction wedge and delay the onset of uplift in the forearc high. Low viscosities promote earlier onset of forearc high uplift and lead to larger morphological variability along the subduction margin. Increasing either the sedimentation rate or viscosity may prevent forearc high formation entirely. The thermo-viscous forearc highs grow at an age set by wedge thermal state as a function of accretionary flux, wedge viscosity, and synorogenic sedimentation. Our models explain vertical motions in south Anatolia and potentially in other accretionary margins, like the Lesser Antilles or Cascadia, during the formation of their broad forearc highs. [ABSTRACT FROM AUTHOR]

Early marine diagenetic dolomite is a rather thermodynamically‐stable carbonate phase and has potential to act as an archive of marine porewater properties. However, the variety of early to late diagenetic dolomite phases that can coexist within a single sample can result in extensive complexity. Here, the archive potential of early marine dolomites exposed to extreme post‐depositional processes is tested using various types of analyses, including: petrography, fluid inclusion data, stable δ13C and δ18O isotopes, 87Sr/86Sr ratios, and U‐Pb age dating of various dolomite phases. In this example, a Triassic carbonate platform was dissected and overprinted (diagenetic temperatures of 50 to 430°C) in a strike‐slip zone in Southern Spain. Eight episodes of dolomitization, a dolostone cataclasite and late stage meteoric/vadose cementation were recognized. The following processes were found to be diagenetically relevant: (i) protolith deposition and fabric‐preservation, and marine dolomitization of precursor aragonite and calcite during the Middle–Late Triassic; (ii) intermediate burial and formation of zebra saddle dolomite and precipitation of various dolomite cements in a Proto‐Atlantic opening stress regime (T ca 250°C) during the Early–Middle Jurassic; (iii) dolomite cement precipitation during early Alpine tectonism, rapid burial to ca 15 km, and high‐grade anchizone overprint during Alpine tectonic evolution in the Early Eocene to Early Miocene; (iv) brecciation of dolostones to cataclasite during the onset of the Carboneras Fault Zone activity during the Middle Miocene; and (v) late‐stage regression and subsequent meteoric overprint. Data shown here document that, under favourable conditions, early diagenetic marine dolomites and their archive data may resist petrographic and geochemical resetting over time intervals of 108 or more years. Evidence for this preservation includes preserved Late Triassic seawater δ13CDIC values and primary fluid inclusion data. Data also indicate that oversimplified statements based on bulk data from other petrographically‐complex dolomite archives must be considered with caution. [ABSTRACT FROM AUTHOR]

Geologic evidence across orogenic plateau margins enables the discrimination of the relative contributions of orogenic, epeirogenic and/or climatic processes that lead to growth and maintenance of those plateaus and their margins. Here, we discuss the mode of formation of the southern margin of the Central Anatolian Plateau (SCAP) and evaluate its time of formation using fieldwork in the onshore and seismic reflection data in the offshore. In the onshore, uplifted Miocene rocks in a dip‐slope topography show monocline flexure over >100 km, km‐scale asymmetric folds verging south, and outcrop‐scale syn‐sedimentary reverse faults. On the Turkish shelf, vertical faults transect the basal latest Messinian of a 10 km fold where on‐structure syntectonic wedges and synsedimentary unconformities indicate pre‐Pliocene uplift and erosion, followed by Pliocene and younger deformation. Collectively, Miocene rocks delineate a flexural monocline at plateau margin scale that is expressed along our on‐offshore sections as a kink‐band fold with a steep flank 20–25 km long. In these reconstructed sections, we estimate a relative vertical displacement of 3.8 km at rates of ca. 0.5 mm/y, and horizontal shortening values <1 %. We use this evidence together with our observations of shortening at outcrop, basin, plateau‐margin and forearc‐system scales to infer that the SCAP forms as a monoclinal flexure to accommodate deep‐seated thickening and shortening since >5 Ma, and to contextualize the plateau margin as the forearc high of the Cyprus subduction system. [ABSTRACT FROM AUTHOR]

Using low-temperature thermochronology on apatite and zircon crystals, we show that the western Reguibat Shield, located in the northern part of the West African Craton, experienced significant cooling and heating events between Jurassic and present times. The obtained apatite fission track ages range between 49 and 102 Ma with mean track lengths varying between 11.6 and 13.3 μm and Dpar values between 1.69 and 3.08 μm. Zircon fission track analysis yielded two ages of 159 and 118 Ma. Apatite (U-Th)/He uncorrected single-grain ages range between 76 and 95 Ma. Thermal inverse modelling indicates that the Reguibat Shield was exhumed during the Early Cretaceous, Late Cretaceous, Palaeocene-Eocene and Quaternary. These exhumation events were coeval with regional tectonic and geodynamic events, and were probably driven by a combined effect of plate tectonics and mantle dynamics. [ABSTRACT FROM AUTHOR]

Pervasive fracture networks are common in many reservoir-scale carbonate bodies even in the absence of large deformation and exert a major impact on their mechanical and flow behaviour. The Upper Cretaceous Jandaíra Formation is a few hundred meters thick succession of shallow water carbonates deposited during the early post-rift stage of the Potiguar rift ( NE Brazil). The Jandaíra Formation in the present onshore domain experienced <1.5 km thermal subsidence and, following Tertiary exhumation, forms outcrops over an area of >1000 km2. The carbonates have a gentle, <5⁰, dip to the NE and are affected by few regional, low displacement faults or folds. Despite their simple tectonic history, carbonates display ubiquitous open fractures, sub-vertical veins, and sub-vertical as well as sub-horizontal stylolites. Combining structural analysis, drone imaging, isotope studies and mathematical modelling, we reconstruct the fracturing history of the Jandaíra Formation during and following subsidence and analyse the impact fractures had on coeval fluid flow. We find that Jandaíra carbonates, fully cemented after early diagenesis, experienced negligible deformation during the first few hundreds of meters of subsidence but were pervasively fractured when they reached depths >400-500 m. Deformation was accommodated by a dense network of sub-vertical mode I and hybrid fractures associated with sub-vertical stylolites developed in a stress field characterised by a sub-horizontal σ1 and sub-vertical σ2. The development of a network of hybrid fractures, rarely reported in the literature, activated the circulation of waters charged in the mountainous region, flowing along the porous Açu sandstone underlying the Jandaíra carbonates and rising to the surface through the fractured carbonates. With persisting subsidence, carbonates reached depths of 800-900 m entering a depth interval characterised by a sub-vertical σ1. At this stage, sub-horizontal stylolites developed liberating calcite which sealed the sub-vertical open fractures transforming them in veins and preventing further flow. During Tertiary exhumation, several of the pre-existing veins and stylolites opened and became longer, and new fractures were created typically with the same directions of the older features. The simplicity of our model suggests that most rocks in passive margin settings might have followed a similar evolution and thus display similar structures. [ABSTRACT FROM AUTHOR]

Zones of anomalously high topography within continental interiors, distant from active plate boundaries, are interpreted as being either dynamically supported by viscous flow in the underlying mantle or influenced by plate tectonics. Constraining the models of their genesis requires accurate data on the timing and dimensions of such features. New apatite fission-track and thermal maturity data from the Illizi Basin in Algeria quantify the magnitude and timing of kilometre-scale uplift and exhumation of the northern flank of the Hoggar swell in North Africa. The findings of this study, integrated with previously published thermochronological data, confirm that long-wavelength regional uplift occurred during the Cenozoic extending over a distance in excess of 1500 km from north to south. The uplift, centred on the Hoggar Massif, significantly impacted the flanking Illizi and Tim Mersoï basins. The combination of thermal history modelling and regional stratigraphic observations indicates that the onset of exhumation of the Illizi Basin likely occurred during the Eocene, broadly coincident with magmatism on the Hoggar Massif to the south and the onset of tectonic shortening in the Atlasic belt to the north. [ABSTRACT FROM AUTHOR]

The western Calabria continental margin forms the transition between the Pliocene to Recent Marsili spreading center and continental Calabria, all parts of the upper plate of the Ionian subduction zone. Integrating high-resolution and crustal seismic images constrained by gravity modeling, we provide a detailed reconstruction of the architecture of the margin and develop a new scheme for its Miocene to present evolution. This time span encompasses the continent-continent collision between Africa and Eurasia, subsequent orogenic collapse and rifting apart between the two continental masses, and the Pliocene to Recent emplacement of oceanic crust in the Vavilov and Marsili basins. The crust of the margin thins from the Calabria coast (∼25 km) to the Marsili continent-ocean transition (∼12 km). On the whole, upper and lower crusts thin proportionally with pure shear geometry. The continental margin is covered by an Oligocene(?) to present sedimentary succession reaching a maximum thickness of ∼6.0 km in the Paola Basin. During the Miocene the continental margin experienced regional shortening accommodated by a large number of mainly west vergent thrusts possibly associated with the late stages of the Kabilo-Calabrian chain. Shortening continued through Pliocene to Recent but was accommodated by a limited number of west vergent thrust faults located in the western part of the margin and by a few tens of kilometers wide syncline located in the eastern part of the profile. The accommodation space created in the syncline core hosted a ∼4.5 km thick, Plio-Quaternary sedimentary succession, the Paola Basin. No significant extensional fault is observed along the profile. Miocene to Recent subsidence was controlled by (1) a short-wavelength component related to shortening and responsible for the formation of the Paola Basin syncline and, possibly, contributing to the uplift of onshore Calabria and (2) a long-wavelength component responsible for the regional subsidence and oceanward tilting of the Calabria margin. Short-wavelength subsidence ended in the late Pliocene, but long-wavelength downward movements persisted and even accelerated during late Pliocene(?) to Quaternary times when the present-day bathymetry was achieved. Both horizontal deformations and vertical movements are difficult to explain in the context of a normal back-arc basin without taking into consideration patterns of secondary mantle flow generated by the retreat of the subducting slab. [ABSTRACT FROM AUTHOR]

The Ligurian Alps segment of the Alpine–Apennine orogen in NW Italy is unconformably covered by Upper Eocene to Holocene sediments in the Tertiary Piedmont Basin (TPB) and Po Plain. These sediments dip towards the north demonstrating the erosional nature of the southern border of the succession and implying that the adjacent orogenic belt formed the substratum rather than the margin of the sedimentary basin. Apatite (U–Th)/He and fission track thermochronology shows that the orogen first subsided and was buried at >4 km from 30 to 26 Ma and began its exhumation thereafter. From 26 Ma to present, this upward movement was contemporaneous with subsidence in the northern TPB. The couple exhumation in the S and subsidence in the N migrated northwards through time. Vertical movements in the area are similar to those reconstructed in Corsica. In both cases, the onset of exhumation becomes younger away from the Ligurian-Provençal basin and has little correlation with the opening of the surrounding oceanic basins. [ABSTRACT FROM AUTHOR]

Structural analysis and paleostress fault slip inversion of the Transylvanian basin and its border regions with the surrounding East and South Carpathians and the Pannonian basin (e.g., the Apuseni Mountains) reveal at least two distinct tectonic phases for the Neogene evolution for the eastern part of the Pannonian basin system. Our main focus is on the role of the Transylvanian basin and its border regions in the Neogene as a transition zone between the extending Pannonian basin and the converging East and South Carpathians. The results provide constraints on the mechanisms responsible for as well the formation of the Transylvanian basin itself as on the relation between the basin-formational processes operating in the Pannonian basin and the contractional history of the East and South Carpathian mountain belt. In the middle Miocene (17-14/12 Myr) the Transylvanian basin underwent E-W extension coeval with the first and major phase of overall E-W extension affecting the Pannonian basin and with submarine accretionary wedge tectonics in the East Carpathian arc. In the late Miocene to early Pliocene (12-8/6 Myr) the Transylvanian basin experienced a strong pulse of E-W oriented shortening coeval with the climax of compression in the East Carpathians and a second rift phase affecting the Pannonian basin. Continued contractional deformation affected the Transylvanian basin during the Pliocene and Pleistocene with compression directions shifting to ESE-WNW directions. [ABSTRACT FROM AUTHOR]

Up to several kilometers deep sedimentary basins of Neogene to Quaternary age are found in the south Adriatic between the Apennines and the Dinarides/Albanides. They are the Apennines foredeep, the Central Adriatic Basin, and the South Adriatic Basin. Two regional seismic lines, 260 and 170 km long, across the entire system provide hitherto unavailable constraints on the kinematics and dynamics of basin development. The Apennine foredeep imaged along the lines, formed in middle to late Pliocene times through a rapid westward tilting of the basin floor. A paleobathymetry of few kilometers was created in which allochthonous bodies were emplaced and sediments deposited unaffected by deformation and farther rotations. The Central and South Adriatic Basins formed in Neogene to Quaternary times and are both characterized by strong subsidence in their central parts, gradually diminishing toward the edges in the SW and NE. Depocenters did not shift laterally through time. Subsidence rates increase through time, and subsidence continued also following the end of main shortening episodes in the Dinarides/Albanides. The Central and South Adriatic Basins form two crustal-scale synclines with subsidence concentrated in their central parts. Basins' geometries and subsidence patterns indicate that the Adriatic crust has undergone (episodes of) buckling since Miocene times. Wavelengths and amplitudes of such folds change along strike corresponding to mechanical changes of the folded medium. [ABSTRACT FROM AUTHOR]

Presents information on a study which described the crustal features and rifted margin formation in north Sicily, Italy and in the south Tyrrhenian Sea. Geology of the south Tyrrhenian Sea and the north Sicily margin; Regional seismic section across the north Sicily rifted margin; Kinematic evolution of the margin.

Examines the tectogenesis of the South Alpine-Apennines foredeep in Italy. Discovery of shallower dips along profiles crossing domains which underwent extension; Continuous weakening of the flexed plate with the increase in the dip and curvature of the loaded plate.

We present the results of quantitative forward modeling of the Sardinian rifted margin of the Tyrrhenian Sea. The purpose of this study is to investigate the thermo-mechanical structure that affects the thinning of the lithosphere across the margin. The role of lithospheric necking during basin formation, constrained by basement topography, Moho depth, and gravity anomalies, is modeled for different compensation models. Independent constraints are obtained from the analysis of the predicted thermal structure. A deep level of necking (25 km) is required to explain the observed crustal geometries and gravity anomaly signature. The model predicts spatial and temporal variations in rheology during extension with important implications for kinematics of lithospheric thinning. Prerift lithospheric conditions, strain rate, and temperature during extension appear to be the key controls on the style of lithospheric rifting and necking in the Tyrrhenian Sea. A forward model for basin stratigraphy is presented for the polyphase history of the Tyrrhenian rifting. This model provides quantitative estimates of time-space dependent crustal thinning and rates of extension. [ABSTRACT FROM AUTHOR]