Static modelling of geological structures for carbon sequestration purposes in the Lorestan area of Iran

One of the most important methods aimed at climate mitigation technology is carbon geological sequestration. During the process of site selection and characterization required for evaluation of capacity storage potential of a given region, geological static modelling plays an essential role by providing a better understanding of the structure in terms of petrophysical and geological characteristics. This work presents the 3D geological model of several anticlines in the Lorestan area (northwestern Zagros), to evaluate their carbon storage capacity potential. The 3D geological model is based on seismic data and well-log data from 2 wells drilled in the area, kindly provided by the National Iranian Oil company (NIOC). Preliminary well logs analysis allowed to identify potential target formations by considering pivotal criteria of CO2 storage such as depth, porosity, and other petrophysical characteristics. The 3D model will be followed by the construction of a geocellular model that will be populated by petrophysical data obtained from well logs. The reconstructed volume will be then used for injection simulations to obtain an evaluation of the volume available for storage. The dynamic simulation will also provide and support the evaluation of other important aspects such as the injection strategies and efficiency coefficient, comparing the observed theoretical and effective capacity

Physical and Transport Property Variations Within Carbonate-Bearing Fault Zones: Insights From the Monte Maggio Fault (Central Italy)

AbstractThe physical characterization of carbonate‐bearing normal faults is fundamental for resource development and seismic hazard. Here we report laboratory measurements of density, porosity, Vp, Vs, elastic moduli, and permeability for a range of effective confining pressures (0.1–100 MPa), conducted on samples representing different structural domains of a carbonate‐bearing fault. We find a reduction in porosity from the fault breccia (11.7% total and 6.2% connected) to the main fault plane (9% total and 3.5% connected), with both domains showing higher porosity compared to the protolith (6.8% total and 1.1% connected). With increasing confining pressure, P wave velocity evolves from 4.5 to 5.9 km/s in the fault breccia, is constant at 5.9 km/s approaching the fault plane and is low (4.9 km/s) in clay‐rich fault domains. We find that while the fault breccia shows pressure sensitive behavior (a reduction in permeability from 2 × 10−16 to 2 × 10−17 m2), the cemented cataclasite close to the fault plane is characterized by pressure‐independent behavior (permeability 4 × 10−17 m2). Our results indicate that the deformation processes occurring within the different fault structural domains influence the physical and transport properties of the fault zone. In situ Vp profiles match well the laboratory measurements demonstrating that laboratory data are valuable for implications at larger scale. Combining the experimental values of elastic moduli and frictional properties it results that at shallow crustal levels, M ≤ 1 earthquakes are less favored, in agreement with earthquake‐depth distribution during the L'Aquila 2009 seismic sequence that occurred on carbonates

Observing mineral dust in northern Africa, the middle east and Europe: current capabilities and challenges ahead for the development of dust services

Mineral dust produced by wind erosion of arid and semi-arid surfaces is a major component of atmospheric aerosol that affects climate, weather, ecosystems, and socio-economic sectors such as human health, transportation, solar energy, and air quality. Understanding these effects and ultimately improving the resilience of affected countries requires a reliable, dense, and diverse set of dust observations, fundamental for the development and the provision of skillful dust forecasts tailored products. The last decade has seen a notable improvement of dust observational capabilities in terms of considered parameters, geographical coverage, and delivery times, as well as of tailored products of interest to both the scientific community and the various end-users. Given this progress, here we review the current state of observational capabilities including in-situ, ground-based and satellite remote sensing observations, in Northern Africa, the Middle East and Europe for the provision of dust information considering the needs of various users. We also critically discuss observational gaps and related unresolved questions while providing suggestions for overcoming the current limitations. Our review aims to be a milestone for discussing dust observational gaps at a global level to address the needs of users, from research communities to nonscientific stakeholders

A slip tendency analysis to test mechanical and structural control on aftershock rupture planes

Large portions of intraplate regions are characterised by relatively uniform stress fields with moderate to large main shock fault-ruptures nucleating on planes successfully predicted by 2D frictional fault reactivation theory. Here we use a slip tendency analysis, based on the notion that slip on a fault is controlled by the ratio of shear stress to normal stress acting on the plane of weakness, to test whether aftershock sequences are also governed by fault reactivation theory within the regional stress field. We observe that aftershocks for two well-documented seismic sequences occurring in extensional and compressional environments, the 1997 M(w)=6.0 Colfiorito sequence (Central Italy) and the 1999 M(w)=7.5 Chi-Chi sequence (Taiwan), respectively, nucleate on planes favourably oriented for frictional fault reactivation. In particular, 89% of 329 and 81% of 121 events for the Colfiorito and Chi-Chi sequences respectively, are the result of fault reactivation processes on geological structures that represent well oriented planes within the regional stress field. This suggests that stress rotations induced by the main shock for these two intracontinental sequences are unlikely. In addition, the percentage of well oriented aftershock rupture planes reaches 100% for Colfiorito and 86% for Chi-Chi if we consider a magnitude threshold above M(w)=3.7 and M(w)=5.0, respectively. We interpret this as the fact that stress heterogeneities if present are generally localised and can influence only small structures capable of generating small magnitude aftershocks. (c) 2007 Elsevier B.V. All rights reserved

Evaporites bearing faults as a tool to understand the deformation processes into the seismogenic zone of the Northern Apennines [Zone di faglia in rocce evaporitiche ed interpretazione dei processi defoimativi nella zona sismogenetica dell'Appennino Settentrionale]

In the Northern Apennines the integration of commercial seismic reflection profiles with the location of the mainshocks of the recent seismic sequences (the 1997 Mw = 6.0 Colfiorito and the 1998 Mw = 5.1 Gualdo Tadino) constrains the nucleation of the major events at ∼6 km of depth within the Triassic Evaporites, TE, formation. In order to investigate the deformation processes responsible for earthquake nucleation we have studied ancient and exhumed Evaporites bearing normal faults cropping out in Tuscany. Within the TE formation, that is a 2.5 km thick sequence, composed of decimetric-to-decameter scale interbeds of foliated gypsumanhydrites and brecciated dolostones, we have studied fault zone architecture and deformation processes of both small (100 m) displacement faults. Small and large scale faults display a relatively well structured internal architecture with a sharp reduction in grain-size between the damage zone (coarse grained protocatclasite) and the fault core (fine/very fine grained cataclasite). Extreme localization of slip to discrete and very thin (Y and B shear up to 10-100 mm) sliding surfaces is observed within the fine-grained dolomitic bearing cataclasite layers within the fault core. Fluid assisted processes have been inferred by fault fracture mesh development with crack and seal textures within dolomite-dominated damage fault zone. The deformation processes observed in the field are consistent with elastic friction behaviour, recorded by random fabric fault rocks developed within localised zones of high shear strain. Coseismic slip along very narrow slip zones ( 700 °C); it is currently under investigation whether such temperature increase which produces thermal decomposition of dolomite and phase transition in anhydrite rocks is able to cause dramatic coseismic slip weakening within the fault zone