Reeshidev B Bansal

US Patent:

20100177595, Jul 15, 2010

Filed:

Jan 7, 2010

Appl. No.:

12/683869

Inventors:

Vijay Khare - Sugar Lane TX, US
Alexander A. Martinez - Houston TX, US
Michael P. Matheney - The Woodlands TX, US
Reeshidev Bansal - Houston TX, US

International Classification:

G01V 1/28

US Classification:

367 73

Abstract:

Method for aligning converted wave seismic reflection data (PS data) with conventional PP seismic reflection data so that both data types may be used to more accurately image the subsurface for hydrocarbon exploration or field development. Amplitude vs. angle (AVA) or amplitude vs. offset (AVO) attributes of PP and PS seismic data are identified and defined, which attributes are theoretically expected to be in phase and optimize seismic resolution in the data. In one embodiment of the invention, such attributes are calculated (), then the same horizons are identified in a series of PP attributes and in a series of PS attributes, then the second series is aligned with the first at the horizon locations (), then a time transfer function is generated and applied to the PS mode data (), and the aligned joint-mode data are inverted () using, for example, AVA attributes.

US Patent:

20140058678, Feb 27, 2014

Filed:

Mar 9, 2012

Appl. No.:

14/110581

Inventors:

Reeshidev Bansal - Spring TX, US
Michael P. Matheney - The Woodlands TX, US
Enru Liu - Sugar Land TX, US

International Classification:

G01V 1/30

US Classification:

702 14

Abstract:

Method for determining fracture orientation and fracture intensity in multiple fractured layers in the subsurface in a layer-stripping manner. Multi-component, multi-azimuth seismic data are required (), from which the horizontal, primarily converted wave, components are selected, and these data are further reduced by selecting only the data for which the survey azimuths are either parallel or perpendicular to the general fracture strike (). If the general fracture trend is unknown, such selective data may be determined by an azimuth-offset scanning process. Layer stripping is performed on azimuth/offset stacks () to produce fracture parameter maps (). All offsets are stacked in those azimuths that produce consistent fracture parameter maps (), then layer stripping is performed () on the stacks to produce final fracture orientation and S-wave time difference maps (). These maps can be used to produce true amplitude fast and slow S-waves ().

US Patent:

20170108602, Apr 20, 2017

Filed:

Aug 30, 2016

Appl. No.:

15/251298

Inventors:

Di YANG - Spring TX, US
Reeshidev Bansal - Spring TX, US
Spyridon K. Lazaratos - Houston TX, US
Jia Yan - Houston TX, US
Anatoly I. Baumstein - Houston TX, US

International Classification:

G01V 1/28
G01V 1/36
E21B 41/00
G01V 1/32

Abstract:

A method, including: obtaining a seismic dataset that is separated into subsets according to predetermined subsurface reflection angle ranges; performing, with a computer, an acoustic full wavefield inversion process on each of the subsets, respectively, to invert for density and generate respective density models; generating acoustic impedances for each of the subsets, as a function of reflection angle, using the respective density models; and transforming, using a computer, the acoustic impedances for each of the subsets into reflectivity sections, wherein the transforming includes normalizing the reflectivity sections by their respective bandwidth.

US Patent:

20170097428, Apr 6, 2017

Filed:

Aug 30, 2016

Appl. No.:

15/251313

Inventors:

HONGCHUAN SUN - SPRING TX, US
ERIC G. WILDERMUTH - SPRING TX, US
JONATHAN LIU - HOUSTON TX, US
REESHIDEV BANSAL - SPRING TX, US
SPYRIDON K. LAZARATOS - HOUSTON TX, US

International Classification:

G01V 1/28
G01V 1/36

Abstract:

A method, including: obtaining a velocity model generated by an acoustic full wavefield inversion process; generating, with a computer, a variable Q model by applying pseudo-Q migration on processed seismic data of a subsurface region, wherein the velocity model is used as a guided constraint in the pseudo-Q migration; and generating, with a computer, a final subsurface velocity model that recovers amplitude attenuation caused by gas anomalies in the subsurface region by performing a visco-acoustic full wavefield inversion process, wherein the variable Q model is fixed in the visco-acoustic full wavefield inversion process.

US Patent:

20160238722, Aug 18, 2016

Filed:

Oct 26, 2015

Appl. No.:

14/922276

Inventors:

Tetyana VDOVINA - Spring TX, US
Reeshidev Bansal - Spring TX, US
Anatoly Baumstein - Houston TX, US
Yaxun Tang - Spring TX, US
Di Yang - Spring TX, US

International Classification:

G01V 1/28
G01V 1/36

Abstract:

A multi-stage FWI workflow uses multiple-contaminated FWI models to predict surface-related multiples. A method embodying the present technological advancement, can include: using data with free surface multiples as input into FWI; generating a subsurface model by performing FWI with the free-surface boundary condition imposed on top of the subsurface model; using inverted model from FWI to predict multiples; removing predicted multiples from the measured data; using the multiple-free data as input into FWI with absorbing boundary conditions imposed on top of the subsurface model; and preparing a multiple free data set for use in conventional seismic data processing.

US Patent:

20160061974, Mar 3, 2016

Filed:

Jul 16, 2015

Appl. No.:

14/801409

Inventors:

Reeshidev Bansal - Spring TX, US
Anatoly Baumstein - Houston TX, US
Tetyana Vdovina - Houston TX, US
Dongxing Wang - Spring TX, US
Hongchuan Sun - Spring TX, US

International Classification:

G01V 1/28
G06F 17/10

Abstract:

Method for performing a full wavefield inversion (FWI) without simulating free-surface multiple reflections. The free-surface multiples are removed from the field gathers of seismic data, which are then used to generate a subsurface velocity model by FWI. In the FWI, the field monopole sources and receivers are replaced with dipole (actual and mirror image) sources and receivers () when model-simulating () synthetic survey data. Also, direct arrivals at the mirror receiver locations are preferably simulated () with the dipole sources for each shot location and added () to the synthetic survey data () for that shot location, resulting in corrected synthetic survey data (), which is used in the FWI to generate residuals. A model update may be computed by back-propagating the residuals by injecting them at both mirror and actual receiver locations.

US Patent:

20160033661, Feb 4, 2016

Filed:

Jul 2, 2015

Appl. No.:

14/790527

Inventors:

Reeshidev Bansal - Spring TX, US
Pavel Dimitrov - Houston TX, US

International Classification:

G01V 1/28
G06F 17/16

Abstract:

A deterministic method for selecting a set of encoding weights for simultaneous encoded-source inversion of seismic data that will cause the iterative inversion to converge faster than randomly chosen weights. The encoded individual source gathers are summed (), forming a composite gather, and simulated in a single simulation operation. The invention creates multiple realizations of the simulation (), each with its own encoding vector () whose components are the weights for the shots in the composite gather. The encoding vectors of the invention are required to be orthogonal (), which condition cannot be satisfied by random weights, and in various embodiments of the invention are related to eigenvectors of a Laplacian matrix, sine or cosine functions, or Chebyshev nodes as given by the roots of Chebyshev polynomials. For non-fixed receiver geometry, an encoded mask () may be used to approximately account for non-listening receivers.

US Patent:

20150012221, Jan 8, 2015

Filed:

Jun 20, 2014

Appl. No.:

14/311045

Inventors:

Reeshidev Bansal - Spring TX, US
Anatoly Baumstein - Houston TX, US
Partha S. Routh - Katy TX, US

International Classification:

G01V 1/30

US Classification:

702 18

Abstract:

Method for using the full wavefield (primaries, internal multiples and free-surface multiples) in inversion of marine seismic data, including both pressure and vertical velocity data (), to infer a subsurface model of acoustic velocity or other physical property. The marine seismic data are separated () into up-going () and down-going () wavefields, and both wavefields are inverted in a joint manner, in which the final model is impacted by both wavefields. This may be achieved by inverting both wavefields simultaneously (), or one after the other, i.e. in a cascaded approach (, or ), for the subsurface properties ().