Fracture network characterisation of the Balmuccia peridotite using drone-based photogrammetry,implications for active-seismic site survey for scientific drilling  

作　　者：Niccolo Menegoni Yuri Panara Andrew Greenwood Davide Mariani Alberto Zanetti Gyorgy Hetenyi 

机构地区：[1]Ali I.Al-Naimi Petroleum Engineering Research Center,King Abdullah University of Science and Technology,Thuwal,23955-6900,Saudi Arabia [2]Chair of Applied Geophysics,Montanuniversit€at Leoben,Leoben,Austria [3]Department of Earth and Environmental Sciences,University of Pavia,Pavia,Italy [4]Institute of Geosciences and Earth Resources,National Research Council(IGG-CNR),Pavia,Italy [5]Institute of Earth Sciences,University of Lausanne,1015,Lausanne,Switzerland

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第10期3961-3981,共21页岩石力学与岩土工程学报（英文）

基　　金：the Swiss National Science Foundation for the grant PP00P2_187199 of project OROG3NY.

摘　　要：The presence of discontinuities(e.g.faults,fractures,veins,layering)in crystalline rocks can be challenging for seismic interpretations because the wide range of their size,orientation,and intensity,which controls the mechanical properties of the rock and elastic wave propagation,resulting in equally varying seismic responses at different scales.The geometrical characterisation of adjacent outcrop discontinuity networks allows a better understanding of the nature of the subsurface rocks and aids seismic interpretation.In this study,we characterise the discontinuity network of the Balmuccia peridotite(BP)in the IvreaeVerbano Zone(IVZ),northwestern Italy.This geological body is the focus of the Drilling the Ivrea eVerbano zonE(DIVE),an international continental scientific drilling project,and two active seismic surveys,SEismic imaging of the Ivrea ZonE(SEIZE)and high-resolution SEIZE(Hi-SEIZE),which aim to resolve the subsurface structure of the DIVE drilling target through high-resolution seismic imaging.For fracture characterisation,we developed two drone-based digital outcrop models(DOMs)at two different resolutions(10^(-3)-10 m and 10^(-1)-10^(3)m),which allowed us to quantitatively characterise the orientation,size,and intensity of the main rock discontinuities.These properties affect the seismic velocity and consequently the interpretation of the seismic data.We found that(i)the outcropping BP discontinuity network is represented by three more sets of fractures with respect to those reported in the literature;(ii)the discontinuity sizes follow a power-law distribution,indicating similarity across scales,and(iii)discontinuity intensity is not uniformly distributed along the outcrop.Our results help to explain the seismic behaviour of the BP detected by the SEIZE survey,suggesting that the low P-wave velocities observed can be related to the discontinuity network,and provide the basic topological parameters(orientation,density,distribution,and aperture)of the fracture network unique to the BP.These,in turn,can

关 键 词：Remote sensing Fracture intensity Digital outcrop model(DOM) Rock discontinuity Fault SEismic imaging of the Ivrea ZonE(SEIZE) IvreaeVerbano Zone(IVZ) Crystalline rock 

分 类 号：X74[环境科学与工程—环境工程] TE21[石油与天然气工程—油气井工程]