| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 367026000 | Threshold set system | 6 |
| 20100177594 | ATTENUATION OF UNWANTED ACOUSTIC SIGNALS BY SEMBLANCE CRITERION MODIFICATION - Methods and related systems are described for modified semblance criterions based on the approach of thresholding the signal energy. A first criterion is derived by posing the problem as that of detecting a signal with energy (or amplitude) greater than the specified threshold and deriving the generalized likelihood ratio test statistic. A second criterion is derived using the same method by posing the problem as that of rejecting any signal with energy (or amplitude) below a specified threshold and detecting it if its energy is above another threshold greater than or equal to the first. These appropriately modify the original semblance criterion which is shown to be equivalent to the GLRT test statistic in the absence of any threshold on the signal amplitude. In addition simpler modifications are also described. Tests on synthetic data illustrate the effectiveness of all these modifications which perform comparably well at suppressing unwanted arrivals while accurately processing the desired signals. | 07-15-2010 |
| 20140003190 | Method for Gas Zone Detection Using Sonic Wave Attributes | 01-02-2014 |
| 20140036627 | LOUDNESS BASED METHOD AND SYSTEM FOR DETERMINING RELATIVE LOCATION OF AN ACOUSTIC EVENT ALONG A CHANNEL - A method for determining relative location of an acoustic event along a channel such as a wellbore includes obtaining two acoustic signals at are obtained at two different and known depths in the wellbore, dividing the acoustic signals into windows, and determining the relative loudnesses of pairs of the windows. The power of the acoustic signals may be used as a proxy for the loudness of the acoustic event, and this determination can be made in the time or frequency domains. The relative depth of the acoustic event can then be determined relative to the two known depths from the relative loudnesses. The acoustic event may be, for example, casing vent flow, gas migration, a leak along a pipeline, or sounds observed in an observation well from a nearby well in which fracking is being performed. | 02-06-2014 |
| 20150378042 | METHODS FOR DETERMINING WELL LOG ATTRIBUTES FOR FORMATION CHARACTERIZATION - A method for characterizing subsurface formations penetrated by a wellbore includes accepting as input to a computer measurements of a physical parameter of the formations made over a selected axial interval of the wellbore. At least one attribute of the measurements is determined from a change in the measurements over the selected axial interval. At least one characteristic of the formations in the selected axial interval using the at least one attribute. | 12-31-2015 |
| 20160116617 | Interactive Event Grouping Method - A technique facilitates enhanced microseismic monitoring. The technique may be applied to source mechanism identification under, for example, ill-conditioned receiver coverage to enhance the resolvability for microseismic monitoring. The microseismic monitoring may be used in hydraulic fracturing monitoring, induced seismicity monitoring, CO2 injection monitoring, other injection monitoring, mining, and/or other techniques which cause microseismic events. | 04-28-2016 |
| 20160202371 | Layered Linear Inversion Techniques For Locating Microseismic Activity | 07-14-2016 |
