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Automated processing Automated processing of large data volumes of large data volumes
for development of the for development of the Hugoton-Panoma Hugoton-Panoma
geomodelgeomodel
Geoffrey C. Bohling, Martin K. Geoffrey C. Bohling, Martin K. Dubois, John Doveton and Alan P. Dubois, John Doveton and Alan P.
ByrnesByrnesKansas Geological Survey
Processing StepsProcessing Steps
• Generation of geologic constraining Generation of geologic constraining variables (logs) from tops setvariables (logs) from tops set
• Prediction of lithofacies from logsPrediction of lithofacies from logs
• Porosity log correctionPorosity log correction
• Computation of water saturation, Computation of water saturation, OGIPOGIP
• Back-calculation of free water levelBack-calculation of free water level
Solution strategySolution strategy
• Excel add-in Kipling2.xla used for Excel add-in Kipling2.xla used for prediction of lithofacies from logs prediction of lithofacies from logs (neural net code in Visual Basic)(neural net code in Visual Basic)
• Remaining steps accomplished with Remaining steps accomplished with special-purpose Excel workbooksspecial-purpose Excel workbooks– Spreadsheet input driving VB codeSpreadsheet input driving VB code– Batch processing of LAS filesBatch processing of LAS files
Geologic constraining Geologic constraining variablesvariables• Depositional environment code (MnM)Depositional environment code (MnM)
– 1 for nonmarine1 for nonmarine– 2 for marine2 for marine– 3 for tidal flat3 for tidal flat
• Relative position curve (RelPos)Relative position curve (RelPos)– 0 at bottom of interval to 1 at top0 at bottom of interval to 1 at top
• Added to well logs for facies predictionAdded to well logs for facies prediction
The solution: GenMnM.xlsThe solution: GenMnM.xls
• Spreadsheet with table of tops, Spreadsheet with table of tops, depositional environment codes for depositional environment codes for each intervaleach interval
• Attached VB code generates LAS files Attached VB code generates LAS files with depositional enviornment code with depositional enviornment code (MnM) and relative position (RelPos) (MnM) and relative position (RelPos) curvescurves
GenMnM.xlsGenMnM.xls
Prediction of facies from Prediction of facies from logslogs
• Using neural net in Excel add-in Using neural net in Excel add-in Kipling2.xlaKipling2.xla
• Until recently, Kipling2.xla called Until recently, Kipling2.xla called neural net function in “R” statistical neural net function in “R” statistical language for training; now all in VBlanguage for training; now all in VB
• Includes batch prediction over LAS Includes batch prediction over LAS filesfiles
Neural NetNeural Net
Training the neural netTraining the neural net
Training for prediction of L10, Chase
4000
5000
6000
7000
8000
9000
10000
0 10 20 30 40 50 60 70 80 90 100
Iteration number
Ob
ject
ive
fun
ctio
n
Prediction on spreadsheet dataPrediction on spreadsheet data
Count of Pred. L10Pred. L10L10 1 3 4 5 7 9 10 Grand Total
1 241 16 1 2 22 2822 8 1 1 103 5 5 10 204 1 15 5 17 21 7 506 1 2 1 47 3 12 43 3 618 10 1 119 3 4 2 9
10 1 14 15Grand Total 262 23 1 35 81 3 58 463
Facies Probabilities, Shankle
0 0.5 1
2540
2552.5
2564.5
2576.5
2588
2600
2611.5
2623
2635
2647
2664.5
2676
2687.5
2699.5
2711
2722.5
2734
2745.5
2757
2768
2780
Elo
gD
epth
NM Silt
NM ShlySilt
Mar Shale & Silt
Mdst/Mdst-Wkst
Wkst/Wkst-Pkst
Fxln Sucrosic (Dol)
Pkst/Pkst-Grnst
Grnst/PA Baff
Moldic/sucrosic dol
Marine SS
Batch prediction on LAS filesBatch prediction on LAS files
Porosity log correctionPorosity log correction
• Variations from reference mineralogy Variations from reference mineralogy (limestone)(limestone)– Regression of log vs. core porositiesRegression of log vs. core porosities
• Washouts in shales Washouts in shales – Remove spikes and associated shouldersRemove spikes and associated shoulders
• Excel worksheet with VB code attachedExcel worksheet with VB code attached– Processes LAS files in specified folderProcesses LAS files in specified folder
Log-core porosity relationshipsLog-core porosity relationships
0
5
10
15
20
25
0 5 10 15 20 25Density porosity (ls equiv)
Co
re p
oro
sity
Facies 1
Facies 2
Facies 3
Facies 4
Washout correctionWashout correction
0.20 0.15 0.10 0.05
Porosity
2840
2835
2830
2825
2820D
ep
th
Wa
sho
ut
Th
resh
old
= 0
.20
mean = 0.07
drops below mean
turns back up
Before replacing peakAfter replacing peakAfter replacing shoulders
Porosity correction Porosity correction worksheetworksheet
Batch OGIP calculationBatch OGIP calculation
• Computes Sw & OGIP vs. depth at wells Computes Sw & OGIP vs. depth at wells from facies, porosity in LAS filesfrom facies, porosity in LAS files
• Uses porosity-Sw transforms by facies; Uses porosity-Sw transforms by facies; need HFWL and initial pressureneed HFWL and initial pressure
• Constant FWL (from spreadsheet) or by Constant FWL (from spreadsheet) or by well (from headers)well (from headers)
• Ditto for initial pressureDitto for initial pressure• Generates LAS files with Sw, OGIP Generates LAS files with Sw, OGIP
curvescurves
Batch OGIP spreadsheetBatch OGIP spreadsheet
Backcalculating FWL from Backcalculating FWL from OGIPOGIP
• Computes FWL at each well that Computes FWL at each well that produces best match between produces best match between volumetric OGIP and mass balance volumetric OGIP and mass balance OGIPOGIP
• Mass balance OGIP (target) for each Mass balance OGIP (target) for each well read from LAS headerswell read from LAS headers
• Other than fitting FWL, works like Other than fitting FWL, works like Batch OGIPBatch OGIP
Bracketing search for FWLBracketing search for FWL
Concluding remarksConcluding remarks
• Flexible, easy batch processing Flexible, easy batch processing crucial to a project of this scalecrucial to a project of this scale
• Excel with VB provides reasonably Excel with VB provides reasonably accessible & inexpensive accessible & inexpensive environment for developing environment for developing customized processing codecustomized processing code
Hugoton Asset Hugoton Asset Management Project Management Project industry partnersindustry partners• Anadarko Petroleum CorporationAnadarko Petroleum Corporation• BP America Production CompanyBP America Production Company• Cimarex Energy CompanyCimarex Energy Company• ConocoPhillips CompanyConocoPhillips Company• E.O.G. Resources Inc.E.O.G. Resources Inc.• Medicine Bow Energy CorporationMedicine Bow Energy Corporation• Osborn Heirs CompanyOsborn Heirs Company• OXY USA, Inc.OXY USA, Inc.• Pioneer Natural Resources USA, Inc.Pioneer Natural Resources USA, Inc.