Petrophysical examples from the Gjøa Field
by Matthew G. Reppert, GdF Suez
Presented on the 5 th of September.
The Gjøa field gas cap overlies an oil leg, with combines in place resources (STOIIP + GIIP) of approx. 100 MSm3 hydrocarbon equivalent in Upper Jurassic reservoir sandstones and siltstones. Petrophysical evaluations and models were initially based on wireline data from three vertical exploration wells for the purpose of Field development sanctioning. LWD data was acquired in all horizontal oil wells, in addition to combined LWD and wireline data in high angle gas wells during the development drilling.
This talk will review the Upper Jurassic reservoir characteristics which impact petrophysical models & interpretations, including matrix properties, clay volume & grain size understanding. Ongoing analyses of the porosity system, and issues of mineralogy and texture on both effective porosity and hydrocarbon saturation estimates will be reviewed. The need for more detailed understanding of logging tools and how to get ‘more out of the data’ will be discussed.
Matthew G. Reppert, CV
Matt is currently a Principal Petrophysicist with GDFSUEZ. He is a Geologist by education and training, having worked for 15 years in Total and ConocoPhillips before switching to Petrophysics at the start of the new millennium. He joined GDFSUEZ in 2008, functioning as well planning coordinator during 4 years of development drilling. He continues under the pretense of Petrophysicist for the asset department in GDFSUEZ.