摘要
One of the most common subsurface data sets that is easily accessible and often underutilized is the acquired measuring while drilling (MWD) gamma ray (GR-GAPI) log. Data is acquired from a given gamma ray tool positioned within the drill string and pulsed up to the surface through the mud column in the wellbore. Typical use of the data is for subsurface geologists, drillers and others to correlate the data to known stratigraphic signatures and steer wells through horizontal target zones. Through that correlation, an association to the geologic stratigraphic column can be made and the team of subsurface scientists adjusts where, how fast, and why they choose to continue drilling. The technique of correlation applies to both the conventional and unconventional application. In the unconventional ap</span><span style="font-family:Tahoma;font-size:12px;">plication, the data is also typically acquired along the length of the horizontal wellbore. From</span><span style="font-family:Tahoma;font-size:12px;"> a petrophysical standpoint, just acquiring a gamma ray can limit the amount of information </span><span style="font-family:Tahoma;font-size:12px;">and ability to fully evaluate the properties along the length of the well. In this study, we share</span><span style="font-family:Tahoma;font-size:12px;"> and demonstrate how to utilize the MWD GR for petrophysical evaluation beyond just a volume of shale or volume of clay interpretation. The workflow will allow full integration of a comprehensive petrophysical evaluation that can then be utilized to support all subsurface understandings and modelling efforts.
One of the most common subsurface data sets that is easily accessible and often underutilized is the acquired measuring while drilling (MWD) gamma ray (GR-GAPI) log. Data is acquired from a given gamma ray tool positioned within the drill string and pulsed up to the surface through the mud column in the wellbore. Typical use of the data is for subsurface geologists, drillers and others to correlate the data to known stratigraphic signatures and steer wells through horizontal target zones. Through that correlation, an association to the geologic stratigraphic column can be made and the team of subsurface scientists adjusts where, how fast, and why they choose to continue drilling. The technique of correlation applies to both the conventional and unconventional application. In the unconventional ap</span><span style="font-family:Tahoma;font-size:12px;">plication, the data is also typically acquired along the length of the horizontal wellbore. From</span><span style="font-family:Tahoma;font-size:12px;"> a petrophysical standpoint, just acquiring a gamma ray can limit the amount of information </span><span style="font-family:Tahoma;font-size:12px;">and ability to fully evaluate the properties along the length of the well. In this study, we share</span><span style="font-family:Tahoma;font-size:12px;"> and demonstrate how to utilize the MWD GR for petrophysical evaluation beyond just a volume of shale or volume of clay interpretation. The workflow will allow full integration of a comprehensive petrophysical evaluation that can then be utilized to support all subsurface understandings and modelling efforts.
