Documents

mrscanner_br.pdf

Categories
Published
of 6
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Share
Description
Direct reservoir answers MR Scanner Applications I Radial profiling of fluid vol- umes and fluid saturations I Direct hydrocarbon charac- terization in fresh, unknown, or varying formation water resistivities, as well as in low-resistivity, low-contrast pay and thin beds I Formation evaluation in rugose boreholes I Thin-bed evaluation from high vertical-resolution measurements I Continuous log of oil viscosity by depth for perforation and completion optimization I Determination of fluid stor
Transcript
  Direct reservoiranswers MR Scanner  Applications  Radial profiling of fluid vol-umes and fluid saturations  Direct hydrocarbon charac-terization in fresh, unknown,or varying formation water resistivities, as well as in low-resistivity, low-contrast pay and thin beds  Formation evaluation inrugose boreholes  Thin-bed evaluation from high vertical-resolution measurements  Continuous log of oil viscosityby depth for perforation andcompletion optimization  Determination of fluid storage volume based on lithology-independent porosity  Residual oil saturation inwater-base muds and residualwater saturation in oil-basemuds Benefits  Measurements taken beyonddamaged zone  Fluids and environmentaleffects identified by radial profiling   Valid interpretations in the presence of borehole rugosityor thick mudcake  Reduced rig time Features  Eccentered, gradient design  Multiple, simultaneous, well-defined depths of investiga-tion (DOIs) up to 4 in.,regardlessof hole size or geometry   Vertical resolution of 7.5 in.  Logging speeds to 3,600 ft/hr   Hydrocarbon characterization  Transverse relaxation time( T  2 ), longitudinal relaxationtime ( T  1 ), and diffusion distri-butions at multiple DOIs Formation evaluation simplicity The MR Scanner* expert magnetic resonanceservice is provided with thenext-generation wireline nuclear mag-neticresonance (NMR) logging tool.Using simultaneous multifrequencymeasurements in a gradient-field design,the MR Scanner tool performs investiga-tions at multiple DOIs in a single pass.Its measurement sequence allows a  profiled view of the reservoir fluids.Deep DOIs enable easy identificationof data-quality problems associated withrugose boreholes, mudcake, and fluidsinvasion; and the measurement depthsare maintained regardless of the holesize, deviation, shape, or temperature. This wireline NMR tool providesnumerous user-friendly and direct-depthlog outputs for immediate input to petro- physical analysis and log interpretation.They include  oil and water saturations for identifi-cation and quantification of pay zones  total and effective porosities for determination of pore volume andstorage capacity  bulk volume irreducible water for determination of water-production rate  crude oil T  2 distributions for deter-mination of oil viscosity and to assist in standard T  2 log interpretation  brine T  2 distributions corrected for hydrocarbon effects for improved pore size analysis  hydrocarbon-corrected Timur-Coates permeabilities for determination of  producibility   T  1 for use when T  2 is unavailable;e.g., when logging in vuggy porositiesor light hydrocarbons.These outputs comprise a detailed for-mation evaluation of the near-wellboreregion and are independent of conven-tional formation evaluation measure-ments,such as resistivity or density. The answers are independent of Archieanalysis and can be derived withouthaving to input water salinity.The advanced design of the MRScanner tool and its ready-to-applycomputations bring simplicity to for-mation evaluation. You don’t have to be an NMR data processing and inter- pretation expert to take advantageof the wealth of information provided by this NMR instrument. Multiple depths of investigation  An important feature of the MR Scanner tool is its multiple-antenna design.The main antenna operates at multiplefrequencies and is used primarily for fluid characterization applications. Ithas three different frequencies of oper-ation corresponding to independentmeasurement volumes (shells) thatform concentric arcs in front of theantenna. Because of the eccenteredmode of operation and sensor design,the four DOIs, ranging from 1.5 to 4 in.,are maintained regardless of hole size,mud type, or temperature.Because the MR Scanner tool makessimultaneous measurements at multipleDOIs, it can provide a profile of satura-tion distribution and formation damagein a single pass. Knowledge of the inva-sion profile lends important insight tothe reverse process of production; andalong with other formation evaluationmeasurements, the MR Scannertooldelivers producibility information thatgoverns overall project economics.The high-resolution antennae operate at a single frequency, which correspondsto a slightly shallower DOI than thatof the main antenna. These antennae provide rock-quality and producibilityanswers, evenin thin beds. The MRScannertool is capable of downloggingfor comparison of main-antenna outputwith high-resolution-antennae output to identify light hydrocarbons. Down-logging saves time and enables acquisi-tion of data in difficult environments. A flexible pulse-sequence programmer allows the parameters measured at themultiple frequencies to be acquired in a single pass, thereby eliminating theneed for multiple logging passes.The sensors can be operated either separately or simultaneously at loggingspeeds to 3,600 ft/hr. Comparison of the responses is used to provide high-resolution identification of fluids with long T  1  values, such as light hydrocarbons.  Fluid saturation depth logging The MR Scanner tool was run through anoil-bearing sand in a well in Louisiana.The log (Fig. 2) shows continuous oil viscosity of approximately 2 cp andindicates there is no moveable water in the oil zone (A). Filtrate invasionfrom the water-base mud was deter-mined to be responsible for the lower oil saturation at the 1.5-in. DOI com- pared with the 2.7 in. DOI (B). Thecurves for water saturation in theflushed zones (SXO) were computedentirely from the MR Scanner data (C). Advanced fluids characterization Diffusion-editing (DE) acquisition methods combined with the multifre-quency capability of the MR Scanner tool providerobust fluid saturation and oil viscosity answers using MRF*Magnetic Resonance Fluid characteriza-tion (Fig. 3).Analysis of MR Scanner diffusion measurements permits hydro-carbon characterization in environ-ments where traditional log analysisfails, such as low-resistivity pay, laminated sequences, and freshwater formations. Figure 4 shows the inter- pretation results as they are provided to the end user.MR Scanner fluid characterizationmeasurements provide initial fluid vis-cosity information much earlier thana full pressure-volume-temperature(PVT)analysis. MR Scanner fluidcharacterizations can be used to optimize fluid sampling, saving  valuable rig time. 1 10 100 1,000 10,000 T  2  (ms)10 –3 10 –4 10 –5 10 –6 Diffusion (cm 2  s –1 )GasWaterOil   Fig. 3. MRF map of gas, oil, and water diffusion versus transverse relaxation time. 1 01 01 1000.4 0(v/v)0.4 0(v/v)(cP)(ohmm)(gAPI)(m)   DOI = 1.5 in.DOI = 2.7 in.   1 01 0SXOViscosityResistivityGammaMD X080 X100 X120 SXOBound WaterFree WaterOilBound WaterFree WaterOil   Fig. 2. MR Scanner saturation profile log. ABC 10 –4 10 –5 10 –6 10 –3 Diffusion (cm 2  s –1 )1010010,00011,000 T  2  (ms) GasWaterOil Fluid Volume Saturation Viscosity (v/v) (v/v) (cP)Water 0.11 0.53 Bound 0.02 0.10 Free 0.09 0.43Oil 0.10 0.47 8.5Gas 0.00 0.00Total 0.21   Fig. 4. Interpretation from MRF processing.  Accurate fluids identification in low-resistivity, low-contrast pay The MR Scanner service was able to identify formation fluids in a low-resistivity,low-contrast pay zone in thedeepwater Gulf of Mexico when theycould not readily be identified withlogging-while-drilling (LWD) logs.Conventional LWD logs show an obvious gas-bearing interval in theupper zone from X400 to X600 (Fig. 5).However, in the lower zone, lowresistivity and the absence of a neutron-density crossover made it difficult toidentify fluid type. The MR Scanner tool was run to resolve the ambiguity.In the upper zone, the exceptionalradial profiling capabilities of the MR Scanner tool showed the gas effect of a porosity decrease as DOIincreased (Fig. 6).In the lower zone, the same gas effectwas observed, and the interval wasdetermined to be gas bearing (Fig. 7).The neutron-density crossover wasbeing suppressed because of thinlaminations in the deepwater turbiditedeposit. The MR Scannerlog also indi-cated the zone had good permeability. 0 (gAPI) 1500.2 (gAPI) 200.4 (v/v) 00.4 (gAPI) 00.3 (ms) 30000.3 (ms) 3000 GRMD (ft)X450X500X550 RES MRP (1.5) MRP (2.7) NPHI DPHI T 2  Dist (1.5 in.) T 2  Dist (2.7 in.)   Gas (MR Scanner)Gas (D-N) Fig. 7. MR Scanner radial profile of lower sand. Deficit on deepershells=gas X800X700X600X500X400X300X700X600X500X400X300X200X100X000X900   0 150 Density   1.832.65(v/v )  Neutron Porosity   500(v/v )  GasDeep Resistivity   0.22 0 (ohmm) GR   ( gAPI ) MD1 : 2400   Fig. 5. Conventional LWD log. 0 (gAPI) 1500.2 (gAPI) 200.4 (v/v) 00.4 (gAPI) 00.3 (ms) 30000.3 (ms) 3000 GRMD (ft) X450X500X550 X600 X650 X700 RES MRP (1.5) MRP (2.7) NPHI DPHI T 2  Dist (1.5 in.) T 2  Dist (2.7 in.)   Gas (MR Scanner)Gas (D-N) Fig. 6. MR Scanner radial profile of upper sand. Deficit on deeper shells=gasGas HydrogenIndex ( φ )10Radial DOIGas(low φ ) Filtrate Gas orwater?
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks