MReX obtained accurate porosity measurements in high-salinity mud
A major offshore operator in the South China Sea needed to obtain accurate NMR porosity measurements that would agree with density/neutron porosity measurements for the formation lithology. The company wanted to identify the gas zone in a deepwater well with a very low mud resistivity of 0.013 ohmm.
The best results would be obtained from performing a wireline logging operation on the 5.875-in. borehole. The Geoscience team of Baker Hughes, a GE company (BHGE), recommended using the MR eXplorer™ (MReX™) nuclear resonance (NMR) service. The MReX service can run efficiently with mud resistivities less than 0.012 ohmm, but this resistitivy was near the maximum. In addition, the small borehole could have an adverse impact on the MReX performance.
NMR logging reveals precise porosity and identifes the reservoir fluid properties. As geology complexity increases, it becomes increasingly challenging to reliably and efficiently get exact data. In high-operating-cost environments, such as deepwater or remote areas, the impact of unproductive logging is amplified. The BHGE team was able to obtain accurate measurements that pervious logging services could not, enabling the operator to make better-informed decisions that would reduce formation testing costs approximately $500,000 USD.
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