公开(公告)号：US09851468B2

公开(公告)日：2017-12-26

申请号：US14433366

申请日：2013-10-04

Applicant: Schlumberger Technology Corporation

Inventor： Michael M. Herron ,  Susan Herron ,  James A. Grau ,  John P. Horkowitz ,  Paul R. Craddock ,  Robert Badry

IPC: G01V11/00 ,  G01N33/24 ,  E21B49/00 ,  G01V5/10

CPC classification number: G01V11/00 ,  E21B49/00 ,  G01N33/246 ,  G01V5/101

Abstract: The accurate determination of formation hydrocarbon or water saturation is a useful step in the petrophysical evaluation of petroleum reservoirs. This disclosure presents a new method for estimating hydrocarbon saturation directly from a porosity log and a total organic carbon (TOC) log. The method is enabled by the recent development of a geochemical spectroscopy logging tool that combines inelastic and capture gamma ray measurements to provide a robust and accurate TOC log. The method differs from the prior approach of using carbon-to-oxygen ratios that is most often applied in cased hole evaluation. The main advantages of this method are that it does not use knowledge of formation water resistivity, it does not rely on a resistivity model, it does not use an extensive calibration database, and it is largely independent of clay or other lithology effects. Here, the principles of the method and the main challenges are described, and calculations that explore uncertainties in the saturation estimates arising from uncertainties in the log inputs are presented. The statistical uncertainty in the estimate of hydrocarbon saturation is as good as 10 saturation units (s.u.) in conventional reservoirs with porosities of 15 porosity units (p.u.) or greater. The method has been applied to the determination of hydrocarbon saturation in a variety of formations, including bitumen-filled dolomite, heavy oil sand, and shaly-sands with both open hole and cased hole wells. The method works equally well in formations drilled and logged with either oil- and water-based mud. The saturation estimates have been benchmarked against a combination of conventional and new logging approaches (e.g., resistivity, magnetic resonance and dielectric logs) and core measurements, with generally excellent agreement among independent determinations. Hydrocarbon saturations can be determined accurately using the method in a number of formation types where conventional methods and models for estimating fluid saturation commonly fail, such as freshwater and unknown water salinity in formations under enhanced oil recovery. The case studies included herein demonstrate that a TOC log derived from geochemical spectroscopy logs can be used to obtain reliable estimates of hydrocarbon saturation in a wide range of environmental conditions and formations.

公开(公告)号：US20150285944A1

公开(公告)日：2015-10-08

申请号：US14433366

申请日：2013-10-04

Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION

Inventor： Michael M. Herron ,  Susan Herron ,  James A. Grau ,  John P. Horkowitz ,  Paul R. Craddock ,  Robert Badry

IPC: G01V11/00 ,  E21B49/00 ,  G01V5/10

CPC classification number: G01V11/00 ,  E21B49/00 ,  G01N33/246 ,  G01V5/101

Abstract: The accurate determination of formation hydrocarbon or water saturation is a useful step in the petrophysical evaluation of petroleum reservoirs. This disclosure presents a new method for estimating hydrocarbon saturation directly from a porosity log and a total organic carbon (TOC) log. The method is enabled by the recent development of a geochemical spectroscopy logging tool that combines inelastic and capture gamma ray measurements to provide a robust and accurate TOC log. The method differs from the prior approach of using carbon-to-oxygen ratios that is most often applied in cased hole evaluation. The main advantages of this method are that it does not use knowledge of formation water resistivity, it does not rely on a resistivity model, it does not use an extensive calibration database, and it is largely independent of clay or other lithology effects. Here, the principles of the method and the main challenges are described, and calculations that explore uncertainties in the saturation estimates arising from uncertainties in the log inputs are presented. The statistical uncertainty in the estimate of hydrocarbon saturation is as good as 10 saturation units (s.u.) in conventional reservoirs with porosities of 15 porosity units (p.u.) or greater. The method has been applied to the determination of hydrocarbon saturation in a variety of formations, including bitumen-filled dolomite, heavy oil sand, and shaly-sands with both open hole and cased hole wells. The method works equally well in formations drilled and logged with either oil- and water-based mud. The saturation estimates have been benchmarked against a combination of conventional and new logging approaches (e.g., resistivity, magnetic resonance and dielectric logs) and core measurements, with generally excellent agreement among independentdeterminations. Hydrocarbon saturations can be determined accurately using the method in a number of formation types where conventional methods and models for estimating fluid saturation commonly fail, such as freshwater and unknown water salinity in formations under enhanced oil recovery. The case studies included herein demonstrate that a TOC log derived from geochemical spectroscopy logs can be used to obtain reliable estimates of hydrocarbon saturation in a wide range of environmental conditions and formations.

公开(公告)号：US09091774B2

公开(公告)日：2015-07-28

申请号：US13833297

申请日：2013-03-15

Applicant: Schlumberger Technology Corporation

Inventor： Jeffrey Miles ,  Robert Badry ,  James A. Grau

IPC: G01V5/04 ,  G01V5/12 ,  E21B47/04 ,  E21B47/08

CPC classification number: G01V5/045 ,  E21B47/04 ,  E21B47/082 ,  G01V5/125

Abstract: A method of analyzing a geologic formation having a borehole therein may include operating at least one tool within the borehole to collect respective borehole dimensions at different depths in the borehole, and collect respective total values for a given element at the different depths in the borehole. Each total value may be based upon both a value for an adjacent portion of the geologic formation and a value for material within the borehole. The method may also include determining each value of the given element in the adjacent portion of the geologic formation based upon the total value and the corresponding borehole dimensions.

Abstract translation: 分析其中具有钻孔的地质构造的方法可以包括在钻孔内操作至少一个工具以收集钻孔中不同深度处的相应钻孔尺寸，并且针对钻孔中不同深度处的给定元件收集相应的总值。 每个总值可以基于地质层的相邻部分的值和钻孔内的材料的值。 该方法还可以包括基于总值和对应的钻孔尺寸确定地质构造的相邻部分中的给定元素的每个值。