Abstract: Systems and methods for estimating surface of fracture per volume of rock are provided. The systems include a logging tool, such as a resistivity tool, for generating a borehole image representative of segments of fractures in one or more planes and a processor for estimating surface of fracture per volume of rock (P32) from the segments without the need for defining the one or more planes bearing the segments. The methods include using a downhole logging tool, such as a resistivity tool, to collect data corresponding to segments of fractures in one or more planes, and estimating surface of fracture per volume of rock (P32) by reconstructing theoretical elliptical fractures from the segment data, calculating length of fracture segment per surface of borehole (P21) for the theoretical elliptical fractures, and deriving P32 from P21.

Abstract: Methods for dip determination from an image obtained by a down-hole imaging tool. For each pixel forming the image, a probability that a symmetry axis coincides with the pixel is determined. A probability map is then generated, depicting the determined probability of each pixel coinciding with the symmetry axis. The probability map and the image are then superposed to generate a mapped image. The symmetry axis is then estimated based on the mapped image. Image pixels coinciding with a boundary of the geologic feature are then selected in multiple depth zones, and a segment of a sinusoid is fitted to the selected image pixels within each depth zone. Dip within each of the depth zones is then determined based on the fitted sinusoid segments therein.

Abstract: Methods for dip determination from an image obtained by a down-hole imaging tool. For each pixel forming the image, a probability that a symmetry axis coincides with the pixel is determined. A probability map is then generated, depicting the determined probability of each pixel coinciding with the symmetry axis. The probability map and the image are then superposed to generate a mapped image. The symmetry axis is then estimated based on the mapped image. Image pixels coinciding with a boundary of the geologic feature are then selected in multiple depth zones, and a segment of a sinusoid is fitted to the selected image pixels within each depth zone. Dip within each of the depth zones is then determined based on the fitted sinusoid segments therein.

Abstract: Systems and methods for estimating surface of fracture per volume of rock are provided. The systems include a logging tool, such as a resistivity tool, for generating a borehole image representative of segments of fractures in one or more planes and a processor for estimating surface of fracture per volume of rock (P32) from the segments without the need for defining the one or more planes bearing the segments. The methods include using a downhole logging tool, such as a resistivity tool, to collect data corresponding to segments of fractures in one or more planes, and estimating surface of fracture per volume of rock (P32) by reconstructing theoretical elliptical fractures from the segment data, calculating length of fracture segment per surface of borehole (P21) for the theoretical elliptical fractures, and deriving P32 from P21.

Abstract: A method for structure modeling of a formation penetrated by multiple wells includes obtaining borehole dips from borehole measurements; filtering the borehole dips based on a dip sequence analysis; computing structural dips based on the filtered dips; computing structural delineation by using the structural dips; projecting the structural dips to horizon point sets based on the structural delineation; and generating stratigraphic surfaces by mapping the projected horizon point sets.

Abstract: A method for structure modeling of a formation penetrated by multiple wells includes obtaining borehole dips from borehole measurements; filtering the borehole dips based on a dip sequence analysis; computing structural dips based on the filtered dips; computing structural delineation by using the structural dips; projecting the structural dips to horizon point sets based on the structural delineation; and generating stratigraphic surfaces by mapping the projected horizon point sets.

Abstract: A method for identifying geological features in an image of an underground formation surrounding a borehole. The method comprising: analysing the image properties to identify image regions and defining segments based on the identified image regions. Then identifying segments corresponding to a group relating to a geological feature and analysing the segments of the group to classify the feature as one of a pre-determined type.

Abstract: The present invention relates to a user-guided dip picking method from electrical borehole images using Hough Transform. It includes defining a top and bottom reference curve, applying the Hough Transform to the borehole image limited by the top and bottom reference dips so that the Hough Transform space is restrained in the neighborhood of the reference dips. A 1D average trace representing the extrema of the 3D Hough parameter space for each depth is then computed and the extrema exceeding a given threshold are search in this 1D trace. The position in the 3D Hough space of an extremum represents a dip event.

Abstract: The present invention relates to a user-guided dip picking method from electrical borehole images using Hough Transform. It includes defining a top and bottom reference curve, applying the Hough Transform to the borehole image limited by the top and bottom reference dips so that the Hough Transform space is restrained in the neighborhood of the reference dips. A 1D average trace representing the extrema of the 3D Hough parameter space for each depth is then computed and the extrema exceeding a given threshold are search in this 1D trace. The position in the 3D Hough space of an extremum represents a dip event.

Abstract: The present invention relates to a method of determining the "P" and "S" wave propagation velocities and the Young's modulus and Poisson's ratio in geological formations. An acoustic transmitter is placed in a borehole, and receivers in another borehole at predetermined heights. The differences in the propagation times of "P" waves and the exact distance between receivers and transmitter enable the velocities of the "P" and "S" waves to be obtained with sufficient accuracy to calculate the constants. The invention is useful in civil engineering.