This paper recounts the challenges faced by an integrated study team working on fields in offshore Malaysia. These challenges included flat production since last rig activity, unwanted water/gas production and modeling difficulties, which led to poor history matches.

The team petrophysicist faced specific technical challenges. The reservoir rock (as evident from cores) is very shaly, with thinly laminated hydrocarbon bearing sands in multiple stacked reservoirs. In addition, the low salinity of the formation water further reduced the contrast between pay and non-pay rocks. The reservoirs are relatively shallow with minimal consolidation, and large washouts commonly affected density/neutron logs. Consequently, fluid typing, fluid contact identification and derivation of petrophysical evaluation parameters posed significant technical challenges.

The paper presents three selected cases that inspired unusual approaches to overcome the foregoing difficulties and also rigorously challenge/support static and dynamic models.

Case One will demonstrate how adapting an innovative permeability prediction method – the Flow Quality Indicator (FQI) Concept - helped to resolve history-matching difficulty in Dynamic simulation. The FQI concept has since been tested successfully in other clastic depositional settings in Brunei and Nigeria.

In Case Two, the model integrity was improved through checking for consistency in input and model data. In particular, a comparison of the conventional wireline saturations and the core-derived saturation profile proved the value of thin-bed evaluation. Further check was to ensure that the resultant group of saturation-height tables covered the full range of rock quality before assigning to model layers.

Case Three draws from the recommendation in Case Two for thin-bed evaluation and demonstrates how reservoir value was maximized in thinly bedded sands. Consequently, hitherto production accounting problem was resolved.

In conclusion, this paper will demonstrate that a challenging environment brings out the best in the team Petrophysicist to make contributions that do result in business game change.

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