Surface-based and point-based algorithms for automated detections of strata and fractures from DOM

Sophie Viseur. ( 2008 )
in: 28th gOcad Meeting, ASGA

Abstract

For recent years, LIDAR techniques are extensively used for geoscienstist applications. Due to LIDAR high flexibility and precision, the number and sizes of virtual outcrop data collections increase drastically implying the development of efficient interpretation methods. A digital outcrop model can contain several imbricated stratigraphic and structural pieces of information from centimeter to decameter scales. The manual geological interpretation of these images is a time consuming process as a result of the great size of the numerical data set. Beyond the effort toconstruct accurate and light Digital Outcrop Model (DOM), it is then of paramount importance to develop tools for interpreting in a automated way strata and fracture locations from DOM. In this scope, we propose two algorithms to help geologists to interpret in a semi-automated way sedimentary structures and fractures from DOM: (1) A surface-based algorithm. It must be applied on DOM that are represented as triangulated surfaces. Differential operators are computed on the topography surface and are used to extrapolate from seed points strata or fracture interpretations. However, the XYZ points that are primarily acquired from LIDAR techniques are often very dense and are then decimated as soon as triangulated surfaces are built to obtain a DOM. (2) We then propose a point-based algorithm that directly works on data points. It uses techniques inspired from image processing algorithms to locally extract geological features from the data points. These two approaches have been tested on real case studies and results will be illustrated and compared.

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    BibTeX Reference

    @inproceedings{ViseurRM2008,
     abstract = { For recent years, LIDAR techniques are extensively used for geoscienstist applications. Due to LIDAR high flexibility and precision, the number and sizes of virtual outcrop data collections increase drastically implying the development of efficient interpretation methods. A digital outcrop model can contain several imbricated stratigraphic and structural pieces of information from centimeter to decameter scales. The manual geological interpretation of these images is a time consuming process as a result of the great size of the numerical data set. Beyond the effort toconstruct accurate and light Digital Outcrop Model (DOM), it is then of paramount importance to develop tools for interpreting in a automated way strata and fracture locations from DOM. In this scope, we propose two algorithms to help geologists to interpret in a semi-automated way sedimentary structures and fractures from DOM: (1) A surface-based algorithm. It must be applied on DOM that are represented as triangulated surfaces. Differential operators are computed on the topography surface and are used to extrapolate from seed points strata or fracture interpretations. However, the XYZ points that are primarily acquired from LIDAR techniques are often very dense and are then decimated as soon as triangulated surfaces are built to obtain a DOM. (2) We then propose a point-based algorithm that directly works on data points. It uses techniques inspired from image processing algorithms to locally extract geological features from the data points. These two approaches have been tested on real case studies and results will be illustrated and compared. },
     author = { Viseur, Sophie },
     booktitle = { 28th gOcad Meeting },
     month = { "june" },
     publisher = { ASGA },
     title = { Surface-based and point-based algorithms for automated detections of strata and fractures from DOM },
     year = { 2008 }
    }