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An up to 1500 m-thick clastic succession, the late Zanclean Baronia Synthem, has been analysed in detail in the Ariano wedge-top Basin (southern Apennine, Italy). In the Baronia Mountains the studied sediments are well exposed and laterally mappable due to young uplift and exhumation and rest unconformably on a complexly deformed pre-Pliocene substratum formed by Triassic to Miocene allochthonous units. The Baronia Synthem has been resolved into seven facies associations that are representative of distinct fluvial, deltaic, nearshore and offshore depositional environments and can be grouped into lowstand, transgressive, and highstand systems tracts. Using an integrated approach comprising original geological field mapping at 1:10,000 scale, conventional sedimentary facies analysis and a sequence stratigraphic approach, this paper provides a detailed description and interpretation of facies associations and new insights on the stratigraphic architecture and the geological history of this portion of the basin fill. [ABSTRACT FROM PUBLISHER]

Abstract: The Oligo-Miocene carbonates pertaining to the Bolognano Formation, cropping out at the Majella Mountain, Italy, are diffusely crosscut by bed-parallel structural elements such as compaction bands and pressure solution seams. These bed-parallel structural elements formed under a vertical loading, during the progressive burial of the carbonates. The present work focuses on the control exerted on their development and distribution by compositional, sedimentological and pore network characteristics of the studied carbonates. The main results are consistent with the following statements: (i) bed-parallel compaction bands developed only within the poorly cemented, porous grainstones (2D porosity > 10%; 3D porosity > 15%); (ii) distribution of these bands was strongly controlled by both sorting and sphericity of the carbonate grains, as well as by the amount of intergranular macroporosity; (iii) bed-parallel pressure solution seams formed, mainly, within the fine-grained packstones, which are characterized by small amounts of clayish matrix (2–4% of total rock volume), and well-sorted, spherical carbonate grains. Considering the impact that burial-related, bed-parallel structures may have on fluid flow, the results provided in this contribution can help the management of subsurface geofluids, and overall prediction of carbonate reservoir quality, by mapping/simulating/assessing carbonate facies. [Copyright &y& Elsevier]

This work focuses on the role played by depositional/diagenetic heterogeneities on the vertical growth of sub-seismic, high-angle structural elements such as joints, sheared joints, small faults, and well-developed faults in Lower Cretaceous tight carbonates exposed along the 100's m-high, km-long, western cliff of the Monte Alpi massif. The study carbonates pertain to the Inner Apulian Platform, and form a surface structural analogue of the fractured carbonate reservoirs currently exploited for hydrocarbon production in nearby areas of southern Italy. By combining traditional field stratigraphic and structural methods with photogrammetric analysis of a large portion of the aforementioned cliff, we assess the abutting and crosscutting relationships among the sub-seismic structural elements and different types of flooding surfaces. At smaller scale, bed interfaces extend laterally for a few tens-of-metres, bound tens-of-centimetres-thick beds characterized by amalgamation and bifurcation geometries, and form sequence boundaries of the 4th-5th order. At larger scale, transgressive surfaces extend laterally for hundreds-of-metres, include mm-thick terrigenous material, bound multiple metre-thick bed packages made up of multiple beds, and form sequence boundaries of the 3rd order. Field evidences are consistent with joints and sheared joints often forming stratabound and non-stratabound elements, respectively. At a reservoir scale, prominent transgressive surfaces are laterally continuous for kilometres, include up to a few centimetres-thick, clay-rich levels and collapsed breccia, bound tens-of-metres-thick bed package associations, and form sequence boundaries of the 2nd order. There, small faults with up to 10's of cm-offset mainly localize within individual bed package associations, whereas well-developed faults with up to a few m-offset crosscut multiple prominent transgressive surfaces. Results after DFN modelling of representative geo-cellular models highlight the control exerted by the study structural elements on the fluid accumulation and flow properties of the fractured carbonates. These data are useful to fill the gap between core and seismic data, as they provide information on the sub-seismic domain (i.e. below seismic resolution). • The work focuses on both dimensional and scalar properties of fractures. • Fracture stratigraphy analysis of Lower Cretaceous limestone is carried out. • Primary heterogeneities drive the vertical growth of small faults and fractures. • Fracture porosity and permeability computed for both outcrop and reservoir scales. [ABSTRACT FROM AUTHOR]

This work focuses on the nature, relative timing, and multi-scale dimensional properties of both background and fault-related fracture networks that crosscut the Lower Cretaceous shallow-water carbonates exposed at the Monte Alpi, southern Italy. Away from the major fault zones, fractures mainly consist of stratabound and non-stratabound joints and sheared joints, which form two main bed-perpendicular cross-orthogonal sets. Both sets are characterized by a Poissonian spacing distribution, they do not form well-defined clusters, and formed during either burial diagenesis or subsequent Upper Miocene foreland flexure of the Inner Apulian Platform. In contrast, the study fault damage zone is mainly crosscut by non-stratabound fractures and through-going slip surfaces, which form clustered conjugate systems characterized by power law spacing distributions. Results of Discrete Fracture Network modelling of geocellular volumes representative of the surveyed outcrops show that the fractured carbonates of the study fault damage zone form the main storage volume for underground fluids. There, non-stratabound fractures act as the main control on fracture porosity and contribute towards determining isotropic horizontal fluid flow properties. These isotropic conditions are interpreted as a factor of the profound control exerted by the pre-existing cross-orthogonal fracture sets, which underwent to an extreme uplift during the Plio-Quaternary tectonic evolution of the area. Data presented in this work also highlight the importance of scan area methods for the quantitative analysis of stratabound fracture sets. • Dimensional and scalar properties of both background and fault-related fracture networks are computed. • Both scanline and scanarea methods are employed for quantitative fracture analysis. • Values of fracture porosity and permeability for host rock dependent upon the methods employed for structural analysis. • Values of fracture porosity and permeability for the fault damage zone are not dependent from the methods employed in field. • Fault damage zones, characterized by quite isotropic horizontal flow properties, form main repositories for underground fluids. [ABSTRACT FROM AUTHOR]

Bed-perpendicular, opening-mode diffuse fractures are common features in carbonate rocks because they become brittle during the first stages of diagenesis. Early-fractures could be independent of tectonics and form a background structural network from sub-millimeter to 10's of centimetres scale. This study focuses on the outcrop-to-micro scales structural, stratigraphic, and petrographic characterization of Lower Cretaceous, shallow-water, tight limestones of the Inner Apulian Platform exposed along the axial sector of the southern Apennines fold-and-thrust belt, Italy. This work aims at understanding the formation of early diagenetic fractures during the first stages of sediment lithification, and on their impact on subsequent deformation mechanisms associated to polyphase tectonics. The results of field structural surveys, of petrographic and cathodoluminescence analyses of representative samples unravel the main structural-diagenetic processes in shallow-water carbonates. We document that early brittle fractures were intrinsically related to the host rock pore type and cementation processes, and summarize the overall time-dependant evolution of the structural assemblages in a conceptual model. This model includes all abutting and crosscutting relationships among the various structural elements from field to thin-section observation, and form the now days fracture network. • Reconstruction of fracture networks nature and relative timing in shallow-water limestones. • Inferences on the carbonate facies control on the structural diagenesis. • New insights into the process of early fracture nucleation. [ABSTRACT FROM AUTHOR]