A heuristic approach to structural consistency of a horizon surface with tectonic faults based on Mallet’s discrete model *

Model and algorithm for constructing a horizon surface in the vicinity of a single fault

Three-dimensional stability analysis of fault-controlled slopes using a column-based composite slip-surface framework

3D models from geological maps: strengths and weaknesses from the Pasubio Massif (Southern Alps)

3D geological models provide digital representations of subsurface architecture and are increasingly applied in both academic research and industry. Their construction can follow implicit or explicit approaches, depending on data availability and final modelling applications. While 3D models based on subsurface data are traditionally employed in several fields of study, models derived from outcrop data are increasingly being developed. In this study, newly acquired geological mapping data from the Pasubio Massif (Southern Alps, northern Italy), covering an area of ~36 km² within the geographic extent of the CARG sheet 081 “Rovereto”, were used to develop and test an iterative explicit workflow for 3D geological modelling using Move software. The workflow is based on the construction of a structured grid of geological cross-sections, followed by the interpolation of stratigraphic horizons and fault surfaces through Ordinary Kriging. Field observations indicate that the lithostratigraphic units cropping out in the study area form a gently NW-dipping monoclinal structure, exhibit overall constant thicknesses and are affected by the Schio-Vicenza fault system. Model validation first involved a qualitative comparison between mapped geological boundaries and faults with those obtained from the intersection of the modelled surfaces with the topography (DEM), followed by thickness maps evaluation as an internal consistency check. Where inconsistencies emerged, cross-sections were refined and the model was iteratively updated until geological geometries and thickness trends became consistent with field-mapped evidence. A final quantitative assessment was then performed by analysing thickness deviations from mean unit thicknesses and by measuring the spatial overlap between mapped and model-interpolated geological boundaries and fault traces. Comparison between the preliminary and validated models, supported by thickness deviation statistics, indicates that most residual discrepancies are constrained within ±10–20% of expected thickness values. The results highlight the critical role of iterative validation in ensuring geologically robust 3D models, emphasising common sources of uncertainty in explicit geomodelling workflows. This study provides a methodological framework for producing reliable 3D geological models in data-poor regions, complementing the recently published ISPRA guidelines for the organisation and standardisation of model datasets and supporting future applications in academic research and regional or national geological surveys.

Application of Tectonic-Physical Approach for Construction of Tectonic Model of the Deeply-Buried Complexes

Recent publications on oil and gas tectonics note the extreme “eclecticism” of the terminology used in the tectonic zoning of the sedimentary basin and surrounding structures, in describing the stage of formation, tectonic conditions, and typification of different-scale discontinuous and plicate structures. The existing situation makes it difficult for researchers to understand each other and leads to the lack of an unified approach in describing the regional tectonic models. Formation of a unified terminology and a common approach in describing tectonic processes is an important and urgent problem. At present, when studying and describing the prospects of oil and gas bearing capacity in the north of the Volga-Urals province, definitions as the Ural geosyncline, TimanPechora province, Pechora-Kolva avlacogen (palaeorift), deep faults and regmatic fault network may be used in one published work. The study of the history of tectonic elements formation in areas with complex geological structure is complicated by overlapping tectonic structures of different order and age. Based on the tectonicphysical approach, authors carried out the reconstruction of the history of tectonic transformations within the study area. When interpreting seismic data of the internal structure of the fault zone, reconstruction of evolution of the formation, tectonic-physical ideas about structural paragenesis were used as a methodological tool. From the tectonic-physical point of view, the fault zone is considered not only as the uniform displacement plane, but as the whole volume of the section, in which genetically related brittle and plastic deformations are manifested. The internal structure of the fault zone is considered as a set of structural elements that determine its kinematics, stage and duration of formation. Application of modern approaches to geological analysis of shear tectonics areas is illustrated by detail analysis of 3D seismic cube data obtained at the territory of the Pechoro-Kozhva megaval. As a result, a new tectonic model was developed. In the conditions of complex deformation history of shear zones, the structures were dated according to their belonging to different-age paragenesis.

QuSI-DEM version 1.0: A polygon-based discrete element sea ice model in spherical coordinates. Part I: Model description

Thin Ice DEM Model Based on Smoothed Elements: A 2.5-Dimensional DEM Approach for Ice–Structure Interaction Simulation