SPE ATCE 2008, Denver

Attendees to the ‘Unconventional Resources’ session learned that these are fast becoming ‘conventional.’ A ‘Data and Decisions’ session discussed rig scheduling and the application of MWD techniques to well intervention. Chevron describes critical path-based ‘under rig floor’ logging.

In the plenary ‘Unconventional Resources’ session, Marshall Atkins (Raymond James Energy Group) noted previous cyclicity as the downturn of the 1980s effectively killed off most unconventional projects. At today’s prices, wind, fuel cells and so on make sense. But if oil doesn’t stay high the situation for unconventionals will be a return to the 1980s.

Chuck Stanley (Questar) recalled that only a decade or so back most US gas came from conventional reservoirs. We still dream of finding such reservoirs, but reality is that unconventional is becoming conventional. Typical tight gas wells show initial decline rates of over 60% and 50% of reserves are produced in 5 years. Gas in place was hugely underestimated in these exotic reservoirs. According to a CERA study, half of US gas comes from tight sands, shales and coal.

Glenn Vawter (NOSA) described oil shales, a.k.a. ‘the rock that burns’ as a huge, untapped resource. In parts of the Piceance basin there are 2 million barrels per acre. Shale oil is a huge resource with great long term potential but it is ‘certainly not a short term play.’

In the ‘data to decisions’ session, Morten Irgens (Actenum) presented work done for Saudi Aramco on scheduling its drilling rigs. Actenum blends artificial intelligence and operational research to increase knowledge workers’ productivity. Today’s decision support applications such as the ubiquitous Microsoft Project does not really cut the mustard. What’s needed is a tool that helps, that criticizes decisions which may be too complex for humans to understand. Saudi Aramco used the tool to plan an optimal drilling sequence for its 130 rigs. Schedules were required to meet targets, minimize transport costs and maximize productivity. Actenum’s tool analyzed 1,500 well locations with 32,000 constraints and competing objectives. There are more ways of scheduling Aramco’s rigs than atoms in the universe. The answer is a ‘two experts’ approach—man and machine sharing the decision.

You would think that in a costly well intervention such as fishing for lost or stuck equipment, that operators in general know what is happening at the tool face. Not so according to Sid Huval (Baker Hughes). Traditional techniques mean that knowledge of what’s going on downhole is often little better than guesswork. The situation is changing with real time logging during well intervention. New downhole sensors have been added to traditional service tools with the results displayed on the rig floor. A compelling case was made for real time observation of milling, debris cleaning and fishing jobs. ‘Now we can see what we’re doing downhole—we need this in every complex well.’

Paul Gregory (Intervera Data Solutions) listed some data management scare stories such as the one where a rig was on standby for five days while engineers tried to confirm that the correct depth has been reached. The information was stored in a drilling and completions database but had been associated with the wrong well. Data forensics allowed the correct well data to be located. Similar mix ups occurred during a fishing job when there was an expensive mix-up over data that belonged to a different lateral. Afterwards a detailed check of the well database revealed that 5% of the client’s wells had similar issues. In all cases the problem was fixed with data quality profiling (DQP). For Gregory, DQP is like anti virus software and should be running in the background continuously monitoring data.

Milad Ershagi (USC, now with Schlumberger) presented a GIS tour de force combining data from the Minerals Management Services’ website with published work from the SPE digital library and other sources, using ArcScene and ArcGlobe for 3D visualization of the whole Gulf of Mexico data set. 30,000 wells and deviation surveys were analyzed with geoprocessing to produce probability surfaces of sands and suggest new targets, using the objective function to forecast production indices.

Schlumberger was showing early results from the integration of ISS’ BabelFish production data access toolset with its Avocet asset management environment. Bablefish plugs a gap in Schlumberger’s offering with customizable visualization of production operations data. One initial target workflow is gas lift optimization. BabelFish provides a map of the operation along with key performance indicators, traffic lights and so on. Drilling further down into the display pulls up well schematics—and allows engineers to fire up applications such as PipeSim in context for nodal analysis.

Julian Pickering outlined the design of BP’s Advanced Collaboration Environment (ACE) for onshore drilling on the Tangguh LNG development, Indonesia. This is the first time BP has used an ACE for drilling performance enhancement, rather than to reduce offshore headcount. WITSML has provided an enhanced data environment suitable for ‘faster and better informed decision making.’ The ACE provides high value problem solving while crossing faults and allows for learning from other operations. The ACE is located in Jakarta and houses an immersive environment with curved screens, built on the control room paradigm. Drilling and completions workflows leverage Halliburton’s DecisionSpace, engineering data model and OpenWorks. The ACE has provided ‘hard benefits’ such as improved recovery from non productive time and abnormal situations. Teething troubles with some WITSML implementations have meant that BP has now set up a WITSML test environment in Aberdeen where vendors’ implementations can be assessed. This test bed is currently running the SiteCom WITSML server—but BP expects Energistics certification to replace in-house testing eventually.

Eric Upchurch presented the results of ‘under rig floor’ logging that Chevron has been using in the Gulf of Thailand for the past couple of years. The idea is simple, the rig is never left idle, after drilling the surface section of one hole, the unit is skidded over to drill a second hole while logging operations progress on the first. Such ‘batch drilling’ operations require modifications to the rig and ‘a very good knowledge of drilling operations.’ Chevron’s wells now take 4½ days to drill, an 11% saving on rig time. Less items in the critical path makes for smoother safer operations.

This report is a brief extract from The Data Room’s Technology Watch report from the 2008 SPE ATCE. More from www.oilit.com/tech.

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