Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes a plurality of optical fibers arranged adjacently to each other and a plurality of bonding regions intermittently spaced along a length of the optical fiber ribbon. At each bonding region, at least one bond is formed between two optical fibers of the plurality of optical fibers. Further, the at least one bond comprises a first material applied to outer surfaces of the two optical fibers and a second material applied over the first material. The first material is different from the second material, and at least one of the first material or the second material includes a colorant configured to identify the optical fiber ribbon. Also disclosed are embodiments of making such an optical fiber ribbon as well as of optical fiber cables including such an optical fiber ribbon.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes a plurality of optical fibers arranged adjacently to each other. Each optical fiber has a circumferential outer surface. The optical fiber ribbon also includes a lengthwise continuous coating disposed on at least a portion of the circumferential outer surface of each optical fiber. The coating includes a colorant for identifying the optical fiber ribbon among a plurality of optical fiber ribbons. The coating has a first thickness. Further, the optical fiber ribbon includes plurality of bonds intermittently formed between adjacent optical fibers of the plurality of optical fibers. Each of the bonds has a second thickness that is greater than the first thickness. The plurality of bonds provide the only connection between the adjacent optical fibers of the plurality of optical fibers.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes a plurality of subunits each comprising a subunit coating surrounding at least two optical fibers arranged adjacently to each other. The subunit coating is made of a first material. A plurality of bonds are intermittently formed between adjacent subunits of the plurality of subunits. The plurality of bonds are made of a second material. The optical fiber ribbon includes a diffusion zone at an interface between each of the plurality of bonds and the subunit coating of each adjacent subunit. Each diffusion zone has a gradient of the second material in the first material. Further, the intermittent bonds may include one or more saddle surfaces formed by intersecting convex and concave curvatures. A method of forming such optical fiber ribbons is also disclosed.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes optical fibers arranged in a row having a first width. Indicator fibers are provided at the edges of the row. The indicator fibers have different color fiber jackets. The optical fiber ribbon also includes a primary matrix into which the plurality of optical fibers is embedded. The optical fiber ribbon also includes an opacifying layer having a second width and a color layer, distinct from the opacifying layer, having a third width. The optical fiber ribbon further includes a layer of printing disposed on an outer surface of the primary matrix. In the optical fiber ribbon, the first width is greater than at least one of the second width or the third width such that the indicator fibers extend past at least one of the opacifying layer or the color layer.

Abstract: A DAS VSP technique is used to determine the induced fracture height and fracture density of an induced fracture region. The DAS VSP technique obtains pre-hydraulic fracturing DAS VSP survey time-lapse data to establish a baseline reference for the direct acoustic wave travel time. The DAS VSP technique obtains one or more time-lapse data corresponding to the subsequent monitor surveys conducted after each hydraulic fracturing stage along the well. Forward modeling is used to determine a theoretical acoustic wave travel time difference. The forward modeling uses seismic anisotropy to describe the behavior of seismic waves traveling through the induced fracture regions. An inversion scheme is then used to invert for the induced fracture height and the fracture density using the forward modeling. The two extracted induced fracture characteristics may then be used to determine optimal hydraulic fracturing parameters.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes a plurality of optical fibers arranged adjacently to each other and a plurality of bonding regions intermittently spaced along a length of the optical fiber ribbon. At each bonding region, at least one bond is formed between two optical fibers of the plurality of optical fibers. Further, the at least one bond comprises a first material applied to outer surfaces of the two optical fibers and a second material applied over the first material. The first material is different from the second material, and at least one of the first material or the second material includes a colorant configured to identify the optical fiber ribbon. Also disclosed are embodiments of making such an optical fiber ribbon as well as of optical fiber cables including such an optical fiber ribbon.

Abstract: An apparatus obtains measurements from a seismic sensor, wherein the seismic measurements include a set of seismic waves having at least a subset of seismic multiples and a machine-readable medium having program code executable by a processor to cause the apparatus to determine seismic measurements of the seismic waves, fit reflectivity model based on a set of reflectivity models using a nonlinear scheme to the seismic measurements, and identify a subset of the seismic measurements corresponding to the subset of seismic multiples. The apparatus also includes program code to cause the apparatus to generate a set of reduced-noise seismic measurements based on attenuation of the subset of the seismic measurements.

Abstract: To mitigate zigzag noise and increase the quality of data provided from DAS VSP in wells with significant vertical sections, zigzag noise characteristics are identified and quantified. The zigzag noise properties can be extracted from an analysis of an autocorrelation of DAS VSP traces. The zigzag noise has a characteristic time period or repeat time delay that is the time period for the noise to propagate along the wireline through a zone of the wellbore with poor acoustic coupling between the fiber optic cable and formation. This period can be identified from analysis of the autocorrelation referred to herein as a crosswise lag summation function. The crosswise lag summation function identifies groups of DAS data traces containing zigzag noise and outputs zigzag noise periodicity for each group of traces. Once it has been identified, the zigzag noise can be removed from the VSP data and improve formation evaluation.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes optical fibers arranged in a row having a first width. Indicator fibers are provided at the edges of the row. The indicator fibers have different color fiber jackets. The optical fiber ribbon also includes a primary matrix into which the plurality of optical fibers is embedded. The optical fiber ribbon also includes an opacifying layer having a second width and a color layer, distinct from the opacifying layer, having a third width. The optical fiber ribbon further includes a layer of printing disposed on an outer surface of the primary matrix. In the optical fiber ribbon, the first width is greater than at least one of the second width or the third width such that the indicator fibers extend past at least one of the opacifying layer or the color layer.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes optical fibers arranged in a row having a first width. Indicator fibers are provided at the edges of the row. The indicator fibers have different color fiber jackets. The optical fiber ribbon also includes a primary matrix into which the plurality of optical fibers is embedded. The optical fiber ribbon also includes an opacifying layer having a second width and a color layer, distinct from the opacifying layer, having a third width. The optical fiber ribbon further includes a layer of printing disposed on an outer surface of the primary matrix. In the optical fiber ribbon, the first width is greater than at least one of the second width or the third width such that the indicator fibers extend past at least one of the opacifying layer or the color layer.

Abstract: The present disclosure discloses a substituted graphane material with a three-dimensional structure. The substituted graphane material comprises a planar substrate with a plurality of six-membered carbon rings comprising continuous sp3 hybrids, wherein an organic molecular ring is connected to the planar substrate due to a Diels-Alder (D-A) reaction.

Abstract: An apparatus includes a seismic sensor to detect seismic waves having at least a subset of seismic multiples and a machine-readable medium having program code executable by a processor to cause the apparatus to determine seismic measurements of the seismic waves, generate a fitted reflectivity model based on a set of reflectivity models using a nonlinear scheme, and identify a subset of the seismic measurements corresponding to the subset of seismic multiples. The apparatus also includes program code to cause the apparatus to generate a set of reduced-noise seismic measurements based on the subset of the seismic measurements.

Abstract: A DAS VSP technique is used to determine the induced fracture height and fracture density of an induced fracture region. The DAS VSP technique obtains pre-hydraulic fracturing DAS VSP survey time-lapse data to establish a baseline reference for the direct acoustic wave travel time. The DAS VSP technique obtains one or more time-lapse data corresponding to the subsequent monitor surveys conducted after each hydraulic fracturing stage along the well. Forward modeling is used to determine a theoretical acoustic wave travel time difference. The forward modeling uses seismic anisotropy to describe the behavior of seismic waves traveling through the induced fracture regions. An inversion scheme is then used to invert for the induced fracture height and the fracture density using the forward modeling. The two extracted induced fracture characteristics may then be used to determine optimal hydraulic fracturing parameters.

Abstract: To mitigate zigzag noise and increase the quality of data provided from DAS VSP in wells with significant vertical sections, zigzag noise characteristics are identified and quantified. The zigzag noise properties can be extracted from an analysis of an autocorrelation of DAS VSP traces. The zigzag noise has a characteristic time period or repeat time delay that is the time period for the noise to propagate along the wireline through a zone of the wellbore with poor acoustic coupling between the fiber optic cable and formation. This period can be identified from analysis of the autocorrelation referred to herein as a crosswise lag summation function. The crosswise lag summation function identifies groups of DAS data traces containing zigzag noise and outputs zigzag noise periodicity for each group of traces. Once it has been identified, the zigzag noise can be removed from the VSP data and improve formation evaluation.

Abstract: Embodiments of the disclosure relate to an optical fiber ribbon. The optical fiber ribbon includes optical fibers arranged in a row having a first width. Indicator fibers are provided at the edges of the row. The indicator fibers have different color fiber jackets. The optical fiber ribbon also includes a primary matrix into which the plurality of optical fibers is embedded. The optical fiber ribbon also includes an opacifying layer having a second width and a color layer, distinct from the opacifying layer, having a third width. The optical fiber ribbon further includes a layer of printing disposed on an outer surface of the primary matrix. In the optical fiber ribbon, the first width is greater than at least one of the second width or the third width such that the indicator fibers extend past at least one of the opacifying layer or the color layer.

Abstract: A system for attenuating coherent noise from seismic data comprises one or more sensors configured to sense waves generated by a seismic source and a coherent noise attenuation module communicably coupled to the one or more sensors and comprising a processor and memory. The coherent noise attenuation module is operable to receive a plurality of traces of seismic data from the one or more sensors and apply a first transformation to the plurality of traces, identify one or more outlier waveforms in the transformed traces, attenuate the identified outlier waveforms, and apply a second transformation to the plurality of traces that is the inverse of the first transformation.

Abstract: A system for attenuating coherent noise from seismic data comprises one or more sensors configured to sense waves generated by a seismic source and a coherent noise attenuation module communicably coupled to the one or more sensors and comprising a processor and memory. The coherent noise attenuation module is operable to receive a plurality of traces of seismic data from the one or more sensors and apply a first transformation to the plurality of traces, identify one or more outlier waveforms in the transformed traces, attenuate the identified outlier waveforms, and apply a second transformation to the plurality of traces that is the inverse of the first transformation.

Abstract: Acquiring seismic input data and computing a structure tensor based on the seismic input data to determine seismic orientation data for one or more subsurface geological features. Kirchhoff migration is applied to the seismic input data and constrained with the seismic orientation data derived from the structure tensor. A seismic depth image based on the Kirchhoff migration as constrained by the structure tensor is then generated for consideration.

Abstract: First-order free-surface multiples recorded in VSP data or reverse VSP data are processed using VSP/CDP method to produce an image of the subsurface. This image produces a larger coverage than that obtained in 3-C 3-D processing of reflection data acquired in the VSP.

Abstract: A walkaway VSP survey is carried out with receivers located in a borehole near the base salt. Reflection tomographic inversion of data from the walkaway VSP is used to derive a velocity model for the subsurface and may be used for imaging of sub-salt reflections.