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GEOLOGY & RESERVOIR ENGINEERING HIGHLIGHTS STRUCTURE The Mann Oil Field is located in the Central Myanmar Basin. The Mann structure is a ten by one mile northwards dipping narrow anticline probably started as an old
The Mann Field Structure ; the blue line shows the path of MPRL E&P’s new 2D line 2010-MPRL-06
RESERVOIR Production in the Mann Oil Field comes from 24 stacked Oligocene-Miocene sandstones deposited in deltaic to shallow sea environments. The producing sands lie between 300 and 9,400 ft in depth. Porosity varies from 10% to 35% with permeabilities are in the 1-1,000 mD range.
HC OCCURRENCES, PRESSURE REGIME & PRODUCTION MECHANISM
INTEGRATION Since 2004, the technical teams are working in an ever increasing integrated manner to better implement and monitor drilling results and calibrating geological and reservoir models using state-of-the-art software and workstations. This integration has allowed to successfully reverse the declining trend of the Mann Production Oil Field by finding and tracking sweet spots especially along faults.
PRODUCTION ENGINEERING HIGHLIGHTS
Sharing of Oil in Mann Production Enhancement Project ( as of April 2011 ) 
Mann Production Split per Activity ( as of April 2011 )
MPRL E&P is using a variety of classical and innovative Enhancement Oil Recovery ( EOR ) methods to successfully reverse the declining production trend of the Mann Field. Additional perforation was first carried out in 2001. After introducing casing swabbing in 2003, MPRL E&P started drilling new infill wells on its own in 2004, starting with Mann-649. MPRL E&P has completed Mann-665 as a light oil producer in September 2009, and is preparing to drill Mann Deep-1 wildcat in June 2011 ( see Mann Deep Project ). Deepening existing wells is an effective way to increase production since mid-2008. Mann Production Split per Activity Managed by MPRL E&P ( as of April 2011 )
CLASSICAL ENHANCEMENT METHODS New Infill Well Drilling Operations
MPRL E&P’s investment in new well drilling between 1999 and June 2010 has resulted in a total of ( 17 ) new wells, as well as one sidetracked directional well in the various fault compartments in the field. These operations, from shallow to medium-deep wells ( 2500 ft - 7000 ft ), were carried out using four drilling rigs, the Gardner Denver II, the Rig Emsco D3 Type2 rigs ( belonging to MOGE ), the Dreco rig AD-1 ( belonging to Asia Drilling Pte Ltd. ) and the pulling unit P-100 belonging to MPRL E&P. The company’s direct rig costs for these operations have been maintained at very low levels, essentially because of its shared responsibilities with MOGE. As a result of these new well drilling operations, MPRL E&P has so far achieved around in excess of 300,000 bbls of additional oil. Furthermore, having ensured that it maintains tight control of its production costs, the company has managed to bring its average drilling cost to US$100/ft for conventional vertical well drilling, and just US$40/ft for well deepening. Based upon these target costs, all drilling operations have a 100% achievement rate in terms of reaching target depth. By March 2011, the Mann Production Enhancement project has produced a total of 4.99 MMbbls of incremental oil above baseline, and given its sound and successful reservoir management process, the company is in general agreement with the estimates of approximately 25 million barrels of recoverable crude oil remaining in the producing reservoirs of the Mann Field. Drilling Operations at Mann-665 ( June 2009 )
Since mid-2008, deepening wells has proven to be the most effective way to fight the decline of the Mann Field. No less than ( 21 ) wells have been deepened, most after mid-2008, including ( 11 ) in the April 2010 to March 2011 fiscal year with a 73% success ratio. The completion with slotted liners rather than perforations of cemented liners, has led to both a decrease in deepening costs and an increase in flow rate, as the formation is less damaged.
Additional perforations have been the oldest method applied by MPRL E&P to increase production, and continues to be quite successful especially considering their low price, with for instance 14 additional perforations conducted during the 2010-2011 fiscal year, resulting in a 79% success ratio. Casing Swabbing Operations Periodic casing swabbing and/or pressure build-up treatment is undergoing on a total of 73 wells ( April 2011 ); the process involves the use of continuous well stimulation for improved production. Two casing swabbing units are used to carry out these operations, which have proven to be very efficient at relatively little costs.
Reopening / Tieback Operations A number of wells which had previously been ‘shut in’ were found to have been producing from only part of the production casing. A full program of reactivation and re-completion of these wells with tieback casing has been undertaken since 2007 as a means of recovering oil from the entire production casing string. Workover Operations
Chemical Treatment Operations Corrosion, scale, paraffin and asphaltene deposit generation has led to acceleration of mechanical failures involving both downhole and surface pumping facilities. Regular, routine chemical treatment has proven to be successful in arresting the decline rate, resulting in stable production and a reduction in downtime. Pump Changing Operations Pump selection is important in order to get effective pumping efficiency for gas locking, sand ingress, high water cut and paraffin problem wells. The use of an insert pump ( top hold-down / bottom hold-down ) has resulted in higher pumping capacity and reduced well downtime. MPRL E&P is putting great efforts into maintaining its workshop for downhole equipments outfitted with state-of-the-art tools. As sands production and paraffin deposits are issues, MPRL E&P is finding the best ways to protect downhole equipments from erosion, stoppage and corrosion. Fishing Operations Some wells were ‘shut in’ in the past as a result of tubing string or packer string becoming lodged or lost down the hole as a result of the formation of water scale and debris. Washover operations, cleaning out with a taper mill or scraper, milling the top of the fish and successful fishing operations have all shown excellent results. INNOVATIVE ENHANCEMENT METHODS MPRL E&P and ministerial authority, MOGE, have agreed on a pioneering work program for implementing three processes which have never been applied in the country before. Multi-lateral Jetting During the 2010 - 2011 fiscal year, MPRL E&P started will apply the multi-lateral jetting technique of SEMJet® by the Maple group from Canada. SEMJet® ( standing for Single Entry Multi-Lateral Jetting ) is unique as it combines in one run the boring of four horizontal laterals up to 300 ft in length through milling a section of the casing and then jetting the formations, an operation which other contract-ors needed up to eight runs to perform. Jetting has the advantage of reaching by-passed oil beyond reservoir damage around the initial borehole. A trial for five wells is proposed in the program. The SEMJET® unit was in the field having experienced some mechanical problems in the operations. Spare parts are being sourced and the pilot project reviewed to two wells. Should these two wells be successful, a campaign involving 10 to 20 wells will be launched, with casing in-situ drilling rather than milling so as to allow a proper directional jetting at several levels, a possibility denied by the casing milling process allowing only one interval to be treated.
Greenzyme
Aphrons Drilling Fluid The Mann Field is generally severely depleted with formation pressure in most reservoirs standing at around ½ the hydrostatic pressure. This means high invasion of the reservoir by drilling fluids even by using light mud.
As part of the recent state policy to conduct operations in the environmentally most respectful manner, MPRL E&P has started an extensive restoration program of the cellars of the producing wells, and in engaging in a policy of zero-discharge into the environment. Cellar Renovation Project Most of the cellars installed by previous operations around producing wellheads in the field are made of bricks precariously covered by mortar cement. These cellars are being progressively replaced by state of the art cellars with liquid-proof cement better adapted to the frequent work-over operations incurred by the ageing producing wells. Water Dumping Project MPRL E&P has engaged in actively returning to the reservoir formations the water from production operations collected in the Gas and Oil Collection & Storage centers. MPRL E&P is carefully targeting disused wells and reservoirs so as to maintain the energy of the reservoir and slow down depletion. MPRL E&P is monitoring the influence of water dumping on surface pressures and flow rate of nearby producers. The project has the dual benefit to slow down the depletion of the field and to dispose of formation slightly salty waters which may degrade the environment if disposed of irresponsibly. CONCLUSION From a project which had previously been regarded by a group of internationally-renowned companies as not economically viable, MPRL E&P has demonstrated its ability to transform the Mann Field into one of the greatest brown field success stories in the region, by successfully lowering operating and capital costs, whilst at the same time, effectively increasing oil production throughout the whole previously depleting field by innovative techniques. * * *
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The oil composition of Mann varies widely from 25° to 47°API in density, and is moderately paraffinic, except for the lighter end. Oil is frequently associated to fairly rich gas. The initial formation pressure regime was significantly over hydrostatic, especially for the deeper reservoirs and in the southernmost compartment of the field. The present pressure regime is below hydrostatic and the oil is now produced mainly by insert pumps. Some sections of the reservoirs remain over-pressured, especially in the deeper reservoirs of the southernmost fault block and in some sections of the main normal faults dissecting the Mann Field. 
The Mann Field, discovered in 1970, was put in production in 1972 and peaked at 24,700 bopd in 1979. Water injection has been applied between the late seventies and progressively abandoned in the late 80’s-early 90’s, generally without much benefit to the field’s production. 
The majority of the company’s drilling operations over recent years have involved infill drilling as well as several different semi-exploratory drilling operations, with the primary objectives in all cases being both to arrest the natural decline rate of the field and to optimize the recovery factor of the existing reservoir. 
Additional Perforations 
In the past, some wells were ‘shut in’ using permanent bridge or cement plugs prior to any conclusive results having been obtained on the sand layers. By drilling out the bridge/cement plug, then initiating a cement squeezing job, cleaning out with circulating pumps and bailing out with a sand pump, many of these wells have been brought back online with significant production results. 
MPRL E&P started in February 2010 using Greenzyme, a protein-based non-living catalyst, as an enzymatic treatment to successfully treat two wells. A third well suffered mechanical problems possibly because of treating unconsolidated sandstones. The supplementary production from the two successful wells paid for the process in less than eight months. Greenzyme, a totally harmless non-pathogenic, biodegradable and recyclable liquid, improves oil recovery by catalyzing breakdown of larger molecules into smaller ones, thus improving the flow characteristics of oil including heavy oil. 
