# US 2014/0150545 A1 · Scattering Detection from Downhole Optical Spectra > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150545 A1 - Document ID: US20140150545A1 - Status: Published application - Kind: A1 - Application number: 13/693,782 - Filed: 2012-12-04 - Published: 2014-06-05 - Earliest claimed: 2012-12-04 - Assignees: Schlumberger Technology Corporation - Applicants: Schlumberger Technology Corporation - Inventors: Kai Hsu; Kentaro Indo; Julian Pop - Web page: https://patentgrep.com/patent/US20140150545A1 ## CPC - E21B 49/0875: {determining specific fluid parameters} - E21B 49/081: {with down-hole means for trapping a fluid sample (E21B49/10 takes precedence)} - E21B 49/088: {combined with sampling} - E21B 49/10: using side-wall fluid samplers or testers - G01N 21/534: {by measuring transmission alone, i.e. determining opacity} - G01N 29/032: by measuring attenuation of acoustic waves - G01N 29/348: {with frequency characteristics, e.g. single frequency signals, chirp signals (measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00)} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract Obtaining in-situ, at a first time, first optical spectral data associated with a formation fluid flowing through a downhole formation fluid sampling apparatus, and then obtaining in-situ, at a second time after the first time, second optical spectral data associated with the formation fluid flowing through the downhole formation fluid sampling apparatus. A wavelength-independent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus is then determined based on the first and second optical spectral data, and a wavelength-dependent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus is determined based on the first and second optical spectral data. ## Claims ### Claim 1 A method, comprising: obtaining in-situ, at a first time, first optical spectral data associated with a formation fluid flowing through a downhole formation fluid sampling apparatus; obtaining in-situ, at a second time after the first time, second optical spectral data associated with the formation fluid flowing through the downhole formation fluid sampling apparatus; determining a wavelength-independent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus based on the first and second optical spectral data; and determining a wavelength-dependent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus based on the first and second optical spectral data. ### Claim 2 (depends on 1) The method of claim 1 further comprising adjusting an operating parameter associated with the downhole formation fluid sampling apparatus based on at least one of the determined wavelength-independent scattering intensity and the determined wavelength-dependent scattering intensity. ### Claim 3 (depends on 2) The method of claim 2 wherein the operating parameter is an operating parameter of a pump of the downhole formation fluid sampling apparatus. ### Claim 4 (depends on 3) The method of claim 3 wherein adjusting the operating parameter of the pump comprises decreasing a flow-rate of the pump based on at least one of the determined wavelength-independent scattering intensity and the determined wavelength-dependent scattering intensity. ### Claim 5 (depends on 1) The method of claim 1 wherein determining the wavelength-independent scattering intensity and the wavelength-dependent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus comprises fitting the first and second optical spectral data with a wavelength-independent scattering coefficient and a wavelength-dependent scattering coefficient. ### Claim 6 (depends on 5) The method of claim 5 wherein determining the wavelength-independent scattering intensity comprises determining a variance of the wavelength-independent scattering coefficient in real-time, and wherein determining the wavelength-dependent scattering intensity comprises determining a variance of the wavelength-dependent scattering coefficient in real-time. ### Claim 7 (depends on 6) The method of claim 6 wherein determining the wavelength-independent scattering intensity comprises detecting when the variance of the wavelength-independent scattering coefficient exceeds a first predetermined threshold, and wherein determining the wavelength-dependent scattering intensity comprises detecting when the variance of the wavelength-dependent scattering coefficient exceeds a second predetermined threshold. ### Claim 8 (depends on 5) The method of claim 5 wherein determining the wavelength-independent scattering intensity and the wavelength-dependent scattering intensity comprises determining in real-time a semblance of the first and second optical spectral data before and after correcting the first and second optical spectral data based on the determined wavelength-independent scattering coefficient and the determined wavelength-dependent scattering coefficient. ### Claim 9 (depends on 1) The method of claim 1 wherein the first and second optical spectral data are obtained at least in part via a multi-channel optical sensor of the downhole formation fluid sampling apparatus, and wherein the multi-channel optical sensor of the downhole formation fluid sampling apparatus comprises at least one spectrometer. ### Claim 10 (depends on 1) The method of claim 1 wherein the downhole formation fluid sampling apparatus comprises a first spectrometer and a second spectrometer, wherein obtaining the first optical spectral data utilizes the first spectrometer, and wherein obtaining the second optical spectral data utilizes the second spectrometer. ### Claim 11 (depends on 1) The method of claim 1 further comprising assessing the quality of at least one answer product based on at least one of the determined wavelength-independent scattering intensity and the determined wavelength-dependent scattering intensity. ### Claim 12 (depends on 11) The method of claim 11 wherein assessing the quality of at least one answer product comprises estimating a gas-to-oil ratio (GOR) of the formation fluid flowing through the downhole formation fluid sampling apparatus based on at least one of the determined wavelength-independent scattering intensity and the determined wavelength-dependent scattering intensity. ### Claim 13 (depends on 1) The method of claim 1 further comprising identifying the size of scattering objects flowing within the downhole formation fluid sampling apparatus based on at least one of the determined wavelength-independent scattering intensity and the determined wavelength-dependent scattering intensity. ### Claim 14 (depends on 1) The method of claim 1 further comprising conveying the downhole formation fluid sampling apparatus within a wellbore extending into the formation, wherein the conveying is via at least one of wireline and a string of tubulars. ### Claim 15 A system, comprising: means for obtaining in-situ: first optical spectral data associated with a formation fluid flowing through a downhole formation fluid sampling apparatus at a first time; and second optical spectral data associated with the formation fluid flowing through the downhole formation fluid sampling apparatus at a second time; and means for determining: a wavelength-independent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus based on the first and second optical spectral data; and a wavelength-dependent scattering intensity within the formation fluid flowing through the downhole formation fluid sampling apparatus based on the first and second optical spectral data. ### Claim 16 (depends on 15) The system of claim 15 further comprising means for automatically adjusting an operating parameter associated with the downhole formation fluid sampling apparatus based on at least one of the determined wavelength-independent scattering intensity and the determined wavelength-dependent scattering intensity, wherein the adjusting means and the determining means are communicably coupled. ### Claim 17 (depends on 15) The system of claim 15 wherein the determining means comprise means for fitting the first and second optical spectral data with a wavelength-independent scattering coefficient and a wavelength-dependent scattering coefficient. ### Claim 18 (depends on 17) The system of claim 17 wherein the determining means comprise means for determining a variance of the wavelength-independent scattering coefficient and the wavelength-dependent scattering coefficient in real-time. ### Claim 19 (depends on 17) The system of claim 17 wherein the determining means comprise means for detecting at least one of: the variance of the wavelength-independent scattering coefficient exceeding a first predetermined threshold; and the variance of the wavelength-dependent scattering coefficient exceeding a second predetermined threshold. ### Claim 20 (depends on 17) The system of claim 17 wherein the determining means comprise means for determining in real-time a semblance of the first and second optical spectral data before and after correcting the first and second optical spectral data based on the determined wavelength-independent scattering coefficient and the determined wavelength-dependent scattering coefficient.