Engineering in Support of Transformative Science Scientific Ocean Drilling of Mid-Ocean Ridge and Ridge-Flank Setting Workshop August 27, 2009 Austin, Texas Greg Myers IODP-MI
Outline o Main engineering needs for young crust drilling o Where do technology gaps exist o Solutions and explanations o Next steps
Primary engineering goals 1. Increasing the quantity and quality of acquired core 2. Increasing the borehole depth achieved The goals for young crust drilling are inline with the primary IODP engineering goals
3.1 Technology Challenges Facing the IODP To achieve the scientific goals identified d in the ISP, there is a range of technology challenges that requires engineering development (Table 2). Table 2. Technology Challenges for the IODP 1 Expand temperature and pressure tolerance 2 Drill/Instrument unstable lithologies and over pressured zones 3 Improve core recovery and quality 4 Improve depth control and cross-instrument depth correlations 5 Develop long-term borehole monitoring systems 6 Develop ability to perform in situ experiments 7 Improve well directional control 8 Make measurements under in-situ conditions 9 Sample at in situ conditions and transfer samples at in situ conditions shipboard 10 Improve hard-rock drilling capabilities 11 Improve remote and post-deployment t capabilities 12 Improve reliability 13 Extend depth capabilities 14 Improve operability under strong currents and severe sea state 15 Magnetic orientation From EDP technology roadmap Version 3.0
Current solutions to primary issues o o o Marine drilling riser Chikyu provides true borehole management system Present riser will operate in water depths up to 2,500 meters Engineering feasibility and scoping underway for 4000 meter riser CDEX is working on extreme length drillstring Drillstring stabilization Active and passive compensation systems are in use in IODP Coordinated system analysis - study to establish a baseline for core quality and quantity
Technology Gaps o Drilling and coring in deep or unstable boreholes in water depths greater than 4,000 m o Over pressured or gas bearing formations drilled with riserless rig o Core recovery and quality still needs improvement in all depths of borehole Recovery % improvement critical in all borehole depths o Reliable hard rock spudding and reentry o Ability to operate in water temperature >200C
Solutions to technology gaps Four main focus areas: o Drillstring i stabilization ti o Spudding and reentry o High temperature o Borehole management
Drillstring Stabilization Techniques o BHA bumper sub Used with limited success pre IODP Enhancements can be made o Passive compensation Presently installed on JOIDES Resolution Refurbished in dry dock, anecdotal evidence suggest core quality / quantity improvement o Active compensation Presently installed on CHIKYU. Effectiveness of system is under investigation. Appears to be providing significant benefit o Seafloor mounted Still conceptual, likely the most effective technological approach Must be developed and is likely to be expensive (cost will be justified by core quality and quantity results)
Spudding and Reentry o Coring and Bit technology High temperature bits (under development by CDEX) Retractable bit technology o Operational techniques not yet developed or utilized For instance, utilization of an ROV to identify and prepare the site prior to mobilization of the drill rig by setting up sub-sea infrastructure o ED A-4: Hard rock re-entry system (HRRS) The current design of the HRRS installs a single string of 16 casing to shallow sub seafloor depths (<30 m). This depth limitation is likely insufficient to isolate the unstable upper crust of morphologically young basalt flows, thus limiting the ability to attack scientific objectives focused on zero age crust. The penetration limitation is partly due to frictional drag along the casing as it follows behind the hammer bit. An improved theoretical design of the hammer-in-casing system uses dual hammers: one hammer at the bit creates the hole and is coupled to a second hammer at the top of the casing, which overcomes the frictional drag and drives the assembly into the bedrock. This development is still completely theoretical at this time. The two bit styles that have been developed with a ring style offer the most promising option.
Spudding and Reentry (cont.) o Sea floor coring systems for acquisition of the upper section rocks ED A-13: Seabed coring devices Explore the application of seabed coring devices to capture the uppermost 0 to 150 m of the seafloor. Several shallow seabed-coring devices have been developed, utilizing high-speed diamond coring techniques employed by the mining/mineral exploration field. Developments in the mid- to late-1990 s sawthe advent of several new seabed corers with extended reach capabilities that are capable of obtaining deeper cores with the addition of rods behind the core barrel. Continued development of these types of tools into the 2000 s has seen these devices become a routine tool for geotechnical operations for collecting not only hard rock cores but CPT data and piston samples as well. Newer seafloor corers have wireline retrieval capabilities and reverse circulation modes for capturing 100 percent of the material drilled.
High Temperature o High quality drilling muds become ineffective beyond 200C o Extreme logging tools will not operate beyond 250C for more than a few hours o Bits and core barrels will fail o ED B-32: Temperature tolerant muds and drilling bits o ED C-1: High temperature electronics, sensors, and sensor systems o ED C-10: Accurate estimates of downhole temperatures
Borehole Management o Drilling fluid is required to: Remove cuttings Provide lithostatic and pore pressure compensation Provide dowhole equipment lubrication i and cooling Develop mud cake on borehole wall to provide additional borehole stability o Historically, seawater with occasional mud sweeps has been utilized, thus the deepest IODP hole is just over 2,111m deep. o To avoid borehole collapse, engineered mud must be circulated continuously as part of a comprehensive plan to drill deeply. This is likely the single most important technological improvement that can be made.
Techniques for borehole management o Existing Riserless drilling - pump and dump Riser - complete mud circulation solution o Emerging Riserless Mud Recovery - mud circulation without blowout prevention o ED B-29: Mud circulation in drilling systems over 2,500- m water depth
DeepStar Riserless Mud Recovery Project The industry funded project identified the requirements for deploying AGR Drilling Services Riserless Mud Recovery system at ultra-deepwater (between 5,000ft and 12,000ft) sites in the Gulf of Mexico aboard a 3 rd generation drillship such as the JOIDES Resolution. A successful test would provide the impetus for lower cost drilling and exploration in water depths of12,000 feet and greater. This enabling technology benefits the IODP science community by providing environmentally friendly drilling access to areas previously not drillable by IODP, this includes deep crustal and overpressure sites. This technology is directly applicable to Chikyu, JOIDES Resolution or MSPs. Sea trials may be targeted as early as mid FY2011.
RMR Status o 1 st generation shallow water capable In operation and available o 2 nd generation deep water (4,800 ft) (1,600 m) In operation and available with modifications o 3 rd generation ultra-deepwater and beyond IODP-MI is working with the oil and gas industry to develop this technology
Deepwater Inline Pump Module
Summary of the RMR TM Benefits Reduced fluid and cement volumes Enables use of engineered fluid systems Predictable setting and cementing of casing at desired depth Extended casing depths to get past troubled zones - save casing strings Early gas kick detection Mud volume control No wash out seen on wells drilled with RMR and inhibitive fluid Improved wellbore stability Mitigation of shallow hazards Flow check of open hole sections Obtain geological information from tophole section Reduced discharge to sea Does not interfere with the wireline coring operation, all cuttings returned to the vessel
Issues to be addressed prior to hyper- deepwater RMR deployment o o o o o Site characterization and well planning Lithology, seabed composition, borehole stress regime, borehole fluid temperature, thermal effects, casing, mud design, etc Vessel modifications Lifting, power, deck space, plumbing Tether management Clash avoidance and fouling gprevention Pumping system modifications Engineering, fabrication and testing Operation simulation Ship crew, drilling crew, ROV operator, RMR operators to simulate hyperdeepwater deployment
Timeline o 2009 - Feasibility project completed by IODP-MI Demonstrated RMR feasibility for IODP to 12,000 (on paper) Funded by DeepStar Industry Consortium o 2011-2012 Field Trial from an IODP platform in <12,000 feet of water Must be preceded by procurement of funding and completion of engineering, vessel modifications and operations simulation Funded partially by DeepStar, RPSEA, major Industry operator/s, cost sharing by AGR and IODP operators o 2013-2014 Field trial in water depth >12,000 feet Must be preceded d by procurement of funding and completion of engineering, vessel modifications and operations simulation o 2015 Ultra-deephole in hyper-deepwater capability could be ready.
RMR platform suitability o <100 m of water - MSP o 100 to 2,750 m of water JOIDES Resolution o 2,750 to >3,650 m of water CHIKYU o Primary factors: Lifting capacity Derrick capability (single vs dual derrick) Bulk material and tubular storage Deck space
EDP INVEST White Paper o The IODP Engineering i Development Panel is developing an engineering white paper for the INVEST meeting which will cover the deep borehole drilling/coring g needs o White paper will be distributed prior to the INVEST meeting and will be available electronically on the IODP website.
To realize these goals o A engineering paradigm shift is needed if we are to achieve these goals as an integrated program. We have extremely high expectations for the technical panels, yet we cannot continue to rely so heavily on volunteer based engineering. We must bolster our engineering resources. Centralized engineering must be able to solicit proposals rather than passively receive them as we do now