24 research outputs found
Lithological control and structural inheritance on faults growth in multilayer foreland sequences
No full textForeland sectors and foredeep-forebulge systems are affected, as the orogenic wedge migrates, by successive stages of stress states and tectonic deformation, resulting in the development of complex fault networks, even if characterized by limited deformation. The role played by structural inheritance and changes in stress field through time, in influencing the successive re-activations of fault segments, is still a topic to be thoroughly investigated. In this work, thanks to an extensive database made available by courtesy of Energean, we were able to investigate a foreland sector at the margin of the southern Apennines. By means of thickness analysis of the Neogene foredeep sequence and of displacement analysis along the fault network, we documented a shift from forebulge-related extension, in Zanclean, to a new tectonic phase, since Piacenzian, related to a strike slip stress field, possibly related to the activity of the Tremiti Fault Zone. We also characterized the geometry and connectivity of the cover-restricted faults, developing above propagating normal faults and observed a clear correlation between fault propagation tendency and lithological/mechanical layering within the cover units
The Impact of Polyphasic Extensional Tectonics on Fault Growth in the Central Apennines Foreland
No full textStructural properties of fractured and faulted Cretaceous platform carbonates, Murge Plateau (southern Italy)
No full textThe Upper Cretaceous carbonates cropping out in the Murge Plateau are good analogues of the fractured and faulted carbonate oil reservoirs of southern Italy. For this reason, a detailed field analysis focused on
structural architecture of fault and fracture networks has been carried out in the Murge Plateau. The well-bedded carbonates exposed there are crosscut by a set of bed-parallel stylolites and two sets of bedperpendicular cross-orthogonal joints/veins. These structural elements were likely formed under vertical loading during burial diagenesis and flexure of the Apulian foreland of the Southern Apennines fold-andthrust belt. Bed-parallel stylolites and bed-perpendicular cross-orthogonal joints/veins represent the background deformation that was overprinted by the fault-related localized deformation. The fault sets
documented in the study area are arranged in two kinematically-compatible fault networks. The first one is made up ofWNW-ESE and NNW-SSE oriented strike-slip faults, right- and left-lateral, respectively, and NWeSE oriented normal faults. The second fault network consists of WNW-ESE oriented left-lateral strike-slip faults, and NEeSW oriented normal faults. First, both architecture and dimensional parameters of the fault and fracture networks have been characterized and computed by means of statistical analysis. Then, the permeability structures associated to the aforementioned networks have been assessed in order to determine the role exerted by fault architecture and dissolution/cementation processes on the fluid storage and migration pathways within the studied platform carbonates. Network 1 faults show a quite variable fluid behavior, in which the fluid flow is strongly affected by inherited structural elements and karst dissolution, whereas network 2 faults show a more uniform, fluid conduit behavior
Scaling relationships and permeability structures of fault zones crosscutting tight Cretaceous platform carbonates (Murge Plateau, southern Italy)
No full textFault zones may exert a first-order control on fluid flow by acting either as a barrier and/or conduit in the
subsurface. Faults often include highly fractured damage zones encompassing cataclastic bodies (fault core) where
most of the deformation is localized. Especially in tight carbonates, both porosity and permeability significantly
increase within the fault damage zones, while the fault cores behave as a hydraulic barrier for cross-fault fluid
flow. The general validity of this hydraulic-deformational characterization of fault zones is influenced by several
factors including displacement distribution, fault geometry, modalities of fault propagation, fault slip direction,
mechanical rock properties and environmental conditions of deformation (mainly lithostatic burial and pore fluid
pressure).
In order to investigate the inner structure of tight platform carbonates, and hence gain new insights on the related
fault permeability, we study the fault dimensional parameters (i.e. damage zone and core thickness variations
relative to the amount of displacement) of different types of faults cropping out in the Murge Plateau, southern
Italy. The Murge Plateau represents the Plio-Pleistocene foreland of the South-Apennines orogenic belt which is
characterized by a relatively-thick lithosphere and a little deformed sedimentary cover. The outcrops in Murge
Plateau are good analogues of the Upper Cretaceous carbonate systems of the peri-Adriatic area that represent
important hydrocarbon reservoirs in southern Italy.
In this work, we compute the scaling relationships between fault dimensional parameters and the cumulative
frequency distributions of the fault-related fracture networks (i.e. spacing and opening). The scaling relationships
are fitted by power-law, logarithmic or exponential relationships, in agreement with different degree of faults
development within the geo-structural contest of this sector of the Apenninic foreland. Based on the relative
thickness between fault damage zones and fault cores, we infer different permeability structures associated to the
studied faults. These last parameters are strongly affected by the presence of both sedimentary dykes, which include
large clasts of breccias, clay material and calcite, and karst that often is present within the fault damage zones
Faults scaling relationships and permeability structures in Cretaceous Platform Carbonates (Murge Plateau, Southern Italy)
No full textThe Upper Cretaceous carbonates cropping out in the Murge Plateau are good analogues of the fractured and faulted carbonate oil reservoirs of southern Italy. For this reason, a detailed field analysis focused on
structural architecture of fault and fracture networks has been carried out in the Murge Plateau. The well-bedded carbonates exposed there are crosscut by a set of bed-parallel stylolites and two sets of bed perpendicular cross-orthogonal joints/veins. These structural elements were likely formed under vertical loading during burial diagenesis and flexure of the Apulian foreland of the Southern Apennines fold-and thrust belt. Bed-parallel stylolites and bed-perpendicular cross-orthogonal joints/veins represent the background deformation that was overprinted by the fault-related localized deformation. The fault sets documented in the study area are arranged in two kinematically-compatible fault networks. The first one is made up ofWNW-ESE and NNW-SSE oriented strike-slip faults, right- and left-lateral, respectively, and NWeSE oriented normal faults. The second fault network consists of WNW-ESE oriented left-lateral strike-slip faults, and NEeSW oriented normal faults. First, both architecture and dimensional parameters of the fault and fracture networks have been characterized and computed by means of statistical analysis. Then, the permeability structures associated to the aforementioned networks have been assessed in order to determine the role exerted by fault architecture and dissolution/cementation processes on the fluid storage and migration pathways within the studied platform carbonates. Network 1 faults show a quite variable fluid behavior, in which the fluid flow is strongly affected by inherited structural elements and karst dissolution, whereas network 2 faults show a more uniform, fluid conduit behavior
Anatomy and kinematic evolution of an ancient passive margin involved into an orogenic wedge (Western Southern Alps, Varese area, Italy and Switzerland)
No full textWe make use of own geological mapping, interpretations of seismic reflection profiles and deep geophysical data to build a lithospheric-scale cross-section across the European Western Southern Alps (Varese area) and to model a progressive restoration from the end of Mesozoic rifting to present-day. Early phases of Alpine orogeny were characterized by Europe-directed thrusting, whereas post-Oligocene shortening led to basement-involving crustal accretion accompanied by backfolding, and consistent with the kinematics of the adjoining Ivrea Zone. Wedging was favored by a significant component of reactivation of the inherited Adriatic rifted margin. Our results also suggest that, during the collisional and post-collisional tectonics, lithosphere dynamics drove diachronically the onset of tectonic phases (i.e., wedging and slab retreat), from east to west, across the Western Southern Alps
Frontal accretion vs. foreland plate deformation: discriminating the style of post-collisional shortening in the Apennines
No full textInterpretation of confidential and public data was carried out in this study focusing on the structural setting and seismic stratigraphy of both foreland basin deposits and underlying shallow water carbonates of the foreland plate. Our structural interpretation, supported by accurate depth conversion of the seismic data and 2D restoration, reveals how the style of deformation of the foreland carbonate platform is dominated by positive inversion involving the oblique-slip reactivation of high-angle, inherited extensional faults rooted below the base of the carbonate succession. Rather than thrust accretion involving the foreland carbonate platform postulated by thin-skinned thrusting models, the observed structures record post-collisional foreland plate deformation associated with the far-field transmission of compressive stresses. Plio-Pleistocene foreland shortening resulted in the formation of segmented positive flower structures arranged in a right-stepping en-échelon pattern and in the coeval development of bending-moment faults accommodating arc-parallel extension in the growing anticlines. Our results emphasize the importance of Permo-Triassic extensional faults during later shortening, reducing on the other hand the role locally played by forebulge-and foreland plate flexuring-related normal faults in inversion structures involving the foreland carbonate platform. Oblique-slip faulting with substantial strike-slip components of motion and associated positive structures exerted a significant control in the development of structural traps and related hydrocarbon accumulation in the deformed foreland plate
Pro-inflammatory genetic profile and familiarity of acute myocardial infarction.
No full textBACKGROUND:
Acute myocardial infarction (AMI) is a multifactorial disease with a complex pathogenesis where lifestyle, individual genetic background and environmental risk factors are involved. Altered inflammatory responses are implicated in the pathogenesis of atherosclerosis and a premature AMI of parents is associated with an increased risk of the disease in their offspring (Offs). However, the genetic background of familiarity for AMI is still largely unknown. To understand which genes may predispose to increased risk of cardiovascular disease gene polymorphism of immune regulatory genes, and clinical events from the Offs of parents with an early AMI were investigated. Genetics data from Offs were compared with those obtained from healthy subjects and an independent cohort of patients with clinical sporadic AMI. Rates of clinical events during a 24 years follow up from Offs and from an independent Italian population survey were also evaluated.
RESULTS:
This study showed that a genetic signature consisting of the concomitant presence of the CC genotype of VEGF, the A allele of IL-10 and the A allele of IFN-γ was indeed present in the Offs population. In fact, the above genetic markers were more frequent in unaffected Offs (46.4%) and patients with sporadic AMI (31.8%) than in the CTR (17.3%) and the differences were highly statistically significant (Offs vs CTR: p = 0.0001, OR = 4.129; AMI vs CTR: p = 0.0001, OR = 2.224). During the 24-year follow-up, Offs with a positive familiarity in spite of a relatively young age showed an increased prevalence of diabetes, ischemic heart disease and stroke. These findings reinforce the notion that subjects with a familial history of AMI are at risk of an accelerated aging of cardiovascular system resulting in cardiovascular events.
CONCLUSION:
Our data suggest that selected genes with immune regulatory functions are part of the complex genetic background contributing to familiarity for cardiovascular diseases. This inflammatory genetic profile, along with classical cardiovascular risk factors, may be used for better defining individual risk of AMI in unaffected subjects
Pro-inflammatory genetic profile and familiarity of acute myocardial infarction
No full textAbstract Background Acute myocardial infarction (AMI) is a multifactorial disease with a complex pathogenesis where lifestyle, individual genetic background and environmental risk factors are involved. Altered inflammatory responses are implicated in the pathogenesis of atherosclerosis and a premature AMI of parents is associated with an increased risk of the disease in their offspring (Offs). However, the genetic background of familiarity for AMI is still largely unknown. To understand which genes may predispose to increased risk of cardiovascular disease gene polymorphism of immune regulatory genes, and clinical events from the Offs of parents with an early AMI were investigated. Genetics data from Offs were compared with those obtained from healthy subjects and an independent cohort of patients with clinical sporadic AMI. Rates of clinical events during a 24 years follow up from Offs and from an independent Italian population survey were also evaluated. Results This study showed that a genetic signature consisting of the concomitant presence of the CC genotype of VEGF, the A allele of IL-10 and the A allele of IFN-γ was indeed present in the Offs population. In fact, the above genetic markers were more frequent in unaffected Offs (46.4%) and patients with sporadic AMI (31.8%) than in the CTR (17.3%) and the differences were highly statistically significant (Offs vs CTR: p = 0.0001, OR = 4.129; AMI vs CTR: p = 0.0001, OR = 2.224). During the 24-year follow-up, Offs with a positive familiarity in spite of a relatively young age showed an increased prevalence of diabetes, ischemic heart disease and stroke. These findings reinforce the notion that subjects with a familial history of AMI are at risk of an accelerated aging of cardiovascular system resulting in cardiovascular events. Conclusion Our data suggest that selected genes with immune regulatory functions are part of the complex genetic background contributing to familiarity for cardiovascular diseases. This inflammatory genetic profile, along with classical cardiovascular risk factors, may be used for better defining individual risk of AMI in unaffected subjects.</p
Relationship between Structure and Stress Field - A Key for Successful HC Exploration in the Northern Zagros Thrust Belt
No full text
