Abstract

A method for mapping acoustic properties of water bottom sediments includes penetrating a piling into the water bottom sediments at a first of a plurality of locations. A first distributed acoustic sensor is inserted adjacent to the first piling. A second piling is driven into sediments at a second location. Acoustic signals are detected at the first acoustic sensor while penetrating the second piling. The detecting is indexed to a depth of the second piling as it is driven. A second acoustic sensor is inserted adjacent to the second piling. Penetrating a piling, detecting acoustic signals at each acoustic sensor and inserting a sensor are repeated until a piling is driven at all the locations. The signals are used to generate a map of properties of the sediments bounded by the plurality of locations. The properties comprise attenuation excluding effects of diffractors in the sediments.

IPC Classes  ?

• G01V 1/143 - Generating seismic energy using mechanical driving means
• E02D 1/00 - Investigation of foundation soil in situ
• E02D 13/06 - Accessories for placing or removing piles or bulkheads for observation while placing
• G01V 1/30 - Analysis
• G01V 1/38 - SeismologySeismic or acoustic prospecting or detecting specially adapted for water-covered areas
• G01V 1/20 - Arrangements of receiving elements, e.g. geophone pattern

Abstract

A method for imaging non-specular seismic events as well as correlating non-specular events with physically measurable quantites in a volume of Earth's subsurface. Includes entering as input to a computer signals detected by a plurality of seismic sensors disposed above and/or within the volume in response to actuation of at least one seismic energy source above and/or within the volume. Parameter analysis is performed to populate the initial model with point-wise, best-fit wavefront travel-time approximations. Imaging is performed to obtain undifferentiated specular and non-specular representations of the volume. Specular boundaries are mapped using the imaged volume and using the boundaries to form a model of specular components of the volume. Beamforming is used to characterize seismic attributes associated with specular and non-specular reflections as separate and differentiated data sets.

IPC Classes  ?

• G01V 1/30 - Analysis
• G01V 1/28 - Processing seismic data, e.g. for interpretation or for event detection
• E21B 49/00 - Testing the nature of borehole wallsFormation testingMethods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
• G01V 1/34 - Displaying seismic recordings
• E21B 7/04 - Directional drilling
• G01V 1/42 - SeismologySeismic or acoustic prospecting or detecting specially adapted for well-logging using generators in one well and receivers elsewhere or vice-versa

Abstract

A method for locating diffractors in subsurface formations includes actuating at least two seismic energy sources at spaced apart locations. Seismic energy is detected in the formations resulting from actuation of the two sources. Signals corresponding to the detected seismic energy are processed to remove components related to direct arrivals from each source. Arrival times of seismic energy in the signals corresponding to energy diffracted from at least one diffractor are identified. The at least one is located diffractor in a plane using the identified arrival times.

IPC Classes  ?

• G01V 1/42 - SeismologySeismic or acoustic prospecting or detecting specially adapted for well-logging using generators in one well and receivers elsewhere or vice-versa