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SEISMIC STRATIGRAPHY

SEISMIC STRATIGRAPHY. SEISMIC STRATIGRAPHY. PROCEDURE. 1. IDENTIFY & MAJOR DEPOSITIONAL UNITS 2. INTEGRATE WELL & SEISMIC 3. ANLYZE REFLECTION CHRACTERISTICS 4. RELATE LITHOLOGY TO SEISMIC 5. PREDICT ENVIRONMENTAL SETTING & LITHOLOGY 6. DETERMINE AN AGE MODEL 7. EVALUATE PREDICTIONS.

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SEISMIC STRATIGRAPHY

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  1. SEISMIC STRATIGRAPHY

  2. SEISMIC STRATIGRAPHY PROCEDURE 1. IDENTIFY & MAJOR DEPOSITIONAL UNITS 2. INTEGRATE WELL & SEISMIC 3. ANLYZE REFLECTION CHRACTERISTICS 4. RELATE LITHOLOGY TO SEISMIC 5. PREDICT ENVIRONMENTAL SETTING & LITHOLOGY 6. DETERMINE AN AGE MODEL 7. EVALUATE PREDICTIONS

  3. SEISMIC STRATIGRAPHY TECHNIQUE 1. SEISMIC SEQUENCE ANALYSIS 2. SEISMIC-WELL TIE 3. SEISMIC FACES ANALUSIS 4. SEISMIC CALIBRATION 5. GEOLOGIC INTERPRETION 6. CHRONOSTRATIGRAPHIC ANALYSIS 7. SEISMIC AND STRATIGRAPHIC MODELING

  4. USING A STRATIGRPHIC FRAMEWORK STRATIGRAPHIC FRAMEWORK ANALYSIS BURIAL HISTORY TRAP DEVELOPMENT AND TIMING MODELING TEMPERATURE HISTORY RESERVOIR PROPERTIES HYDROCARBON GENERATION PREDICTION SOURCE MIGRATION RESERVOIR SEAL TRAP

  5. SCALE OF DEPOSITION CONTROLS EPISODIC • STORMS • FLOODS • TIDES LAMINA LAMINASET BED BEDSET PARASEQUENCE PARASEQUENCESET SEQUENCE INCREASING • SHIFTING SEDIMENT DISTRIBUTION PATTERNS • SEA-LEVEL FLUCTUATIONS • LONG-TERM TECTONICS CYCLIC EPSODIC VS CYCLIC DEPOSOTION

  6. DEPOSITIONAL SEQUECES BEDS FORMATION A SINGLE EPISODE OF DEPOSITION A SINGLE CYCLE OF DEPOSITION BOUNDING SURFACES BEDDING PLANES UNCONFORMITIES • LIMITED EXTENT • SMALL THICKNESS • TERMINATES WHERE • BEDDING SURFACES INTERSECT MORPHOLOGY • WIDESPREAD • THICK ENOUGH TO RESOLVE SEISMICALLY • TERMINATES AGAINST UNCON-FORMITIES OR THEIR CORRELATIVE BED VS DEPOSITIONAL SEQUENCES

  7. SEISMIC REFLECTION • GENERATED AT PHYSICAL SURFACES ACROSS WHICH THERE IS A CHANGE IN IMPEDENCE • POLARITY IS DETERMINED BY SIGN OF THE REFLECTION COEFFCIENT • AMPLITUDE IS A FUNCTION OF: • - MAGNITUDE OF THE REFLECTION COEFFCIENT • - SHARPNESS OF THE REFLECTION COEFFCIENT • - RESOLUTION OF THE SYSTEM

  8. GENERATING FEATURE TIME-STRATIGRAPHY UNCONFORMITIES YES YES SEPARATES OLDER STRATA BELOW FROM YOUNGER STRATA ABOVE STRATAL SURFACES REFLECTION AND TIME-STRATIGRAPHY

  9. SEISMIC RESPONSE OF STARATAL SURFACES • SEISMIC REFLECTIONS PARALLEL STARATAL SURFACES • RESOLUTION IS COMMONLY AT SCALE OF PARASQUENCES • REFLECTION TERMINATION INDICATES THE ASSOCIATED STRATAL UNIT HAS: • - ENDED ABRUPTLY (TRUNCATION) • OR • - THINNED BELOW RESOLUTION (LABOUT)

  10. LOCATE UNCONFORMITIES • AT THE BASE OF ONLAPS AND DOWNLAPS • HALF CYCLE ABOVE TRUNCATION AND TOPLAP MARK • ONSETS (ZERO-CROSSINGS) FRO MINIMUM PHASE • PEAKS?TROUGHS FOR ZERO PHASE REFLECTION CHARECTERISTICS CAN VARY ALONG AN UNCONFORMITY MARKING THE SEISMIC SECTION

  11. SEISMIC REFLECTIONS DO NOT FOLLOW • FACIES BOUNDARIES HOWEVERE • REFLECTION CHRACTERISTICS ARE AFFECTED BY CHANGES IN THE FACIES • - REFLECTION AMPLITUDE • - REFLECTION CONTINUITY • - REFLECTION POLARITY SEISMIC RESPONSE OF FACIES CHANGES

  12. LIMITATIONS RESOLUTION • VERTICAL • LATERAL IMPROPER POSITIONING REFLECTIONS • DIP ANALOG SECTION • OUT-OF-PLANE REFLECTION NONPRIMARY REFLECTIONS • NONCOHERENT NOISE • COHERENT NOISE

  13. SEISMIC SEQUENCE ANALYSIS SEISMIC DATA CHRONO-STRATIGRAPHIC FRAMEWORK SEISMIC SEQUENCES SEISMIC FACIES ANALYSIS SEISMIC REFLECTION CHARACTERISTICS GEOLOGIC INTRPRETATION DEPOSITIONAL FRAMEWORK DEPOSITIONAL ENVIRONMENT LITHOLOGY PREDICTION LITHOLOGY PREDICTION

  14. REFLECTION GEOMETRIES REFLECTION CHARACTERISTICS LOG ANALYSIS CORE ANALYSIS CALIBRATION INTERPRETATION FACIES MODEL DEPOSITIONAL ENVIRONMENT SEDIMENT SUPPLY PRIDICTION SEISMIC FACIES ANALYSIS APPROACH SEISMIC FACIES ANALYSIS

  15. OBSERVE VARIATIONS IN CORES, ON LOGS AND ON SEISMIC CALIBRATE • LOG RESPONSE TO CORE LITHOFACIES • SEISMIC PESPONSE TO CORES AND LOGS INTERBRATE DEPOSITIONAL ENVIRONMENTS SUBENVIRONMENTS SETTING PREDICT LATERAL AND VERTICAL LITHOLOGIC DISTRIBUTION INTEGRATED FACIES ANALYSIS WELL AND SEISMIC DATA

  16. REFLECTION GEOMETRIES • TERMINATION PATTERN • INTERNAL CONFIGRATION • EXTERNAL FORM REFLECTION CHARACTERISTICS • AMPLITUDE • CONTINUITY • FREQUENCY INTERVAL VELOCITY SEISMIC FACIES PARAMETERS

  17. REFLECTION GEOMETRIES INTERNAL CONFIGURATIONS UNSTRATIFIED STRATIFIED SIMPLE PROGADATIONAL COMPLEX CHAOTIC REFLECTION FREE • SEGMIOD • OBLIQUE • COMBINATION • SHINGLED • MOUNDED • HUMMOCHY • DEFORMED • BARALLEL • SUBPARALLEL • DIVERGENT

  18. REFLECTION GEOMETRIES EXTERNAL FORM UNIFORM THICKNESS VARYING THICKNESS • SHEET-EVEN • SHEET-DRAPE • SHEET-SMOOTHING • FILL • MOND • COMBINATION

  19. EROSION TOPLAP CONCODANT ONLAP DOWNLAP CONCORDANT PARALLEL SUBPARALLEL DIVERGENT SIGMOID OBLIQUE SHINGLED MOUNDED HUMMOCKY DEFORMED GEOMETRIC PARAMETERS ABC TECHNIQUE

  20. DEPOSITIONAL ENERGY HIGH LOW DEPOSITIONAL PROCESSES SEDIMENTARY FACIES DIAGNOSTIC GEOMETRIES EXPLORATION • ACTIVE • SORTED • COARSEST AVAILABLE GRAIN SIZE • TOPLAB/OBLIQUE • MOUNDS • QUIET WATER • POOR SORTING • FINE PRESENT • SHEET/DRAPE • SIGMOID PROG. • SLOPE FRONT FILL

  21. AMPLITUDE CONDITIONS LITHOLOGY UNIFORM ALTERNATING VARYING MASSIVE INTERFINGERED DISCONTINUOUS LOW HIGH VARIABLE CONTINUITY DEPOSITION HIGH WIDESPREAD REFLECTION CHARECTERISTICS AND DEPOSITIONAL ENERGY

  22. I) ESTABLISH CHORONOSTRATIGRAPHIC FRAMEWORK • SEISMIC SEQUENCE ANALYSIS • TIE WELL AND SEISMIC II) DEVELOP DEPOSOTIONAL FRAMEWORK • ANALYZE REFLECTION GEOMETRIES • TIE WELL AND SEISMIC • INTERPRET DEPOSITIONAL SETTING • CALIBRATE SEISMIC FACIES • EXTRAPOLATE AWAY FROM WELL(S) • USE FACIES MODELS • USE CONCEPT OF DEPOSITIONAL ENERGY LITHOLOGY PREDICTION

  23. VISUAL SEISMIC SIGNATURES OF HYDROCARBON INDICATORS • AMPLITUDE ANOMALY • FREQUENCY ANOMALY • TIME SAG • ABRUPT TERMINATIONS • PHASE CHANGE • FLUID CONTACT REFLECTION • SHADOW ZONE • CHINMEY

  24. LOW IMPEDANCE ROCKS • FLAT REFLECTIONS NOT RELATED TO FLUID CONTACTS • INCORRECT SECTION POLARITY • LOW GAS STATURATION RESERVOIRS • PROSITY PRESERVATION BY PRESENCE OF HYDROCARBONS - STRATIGRAPHY - MULTIPLES FALSE HDI’S AND PITFALLS

  25. TECHNIQUES ADVANTAGES DISADVANTAGES MISS STRUCTURES THAT STRIKE SUB-PARALLEL TO LINES INACCURATE 3-D TIES OF HORIZONS & STRUCTURES MAPPING IS ADDITIONAL STEP CUMBERSOME CHEAP NO SPECIAL EQUIPMENT FAST IN STRUCTURALLY SIMPLE AREAS MANUAL (SERIAL OVERLAY) WITHOUT TIME SLICES, FEW CROSS LINES PRELIMINARY EVALUATION 2-D INTERPRETATION TECHNIQUES

  26. PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES TECHNIQUES ADVANTAGES DISADVANTAGES MANUAL BUT WITH TIME SLICES (GS) SEISCROP EASY TO RECOGNIZE STRUCTURES IN MOST ORIENTATIONS ACCURATE 3-D TIES OF HORIZONS & STRUCTURES FAST WITH GOOD REFLECTION QONTINUITY EXPENSIVE AND SLOW TO MAKE FILM DIFFICULT TO TIE LINES (PAPER) TO TIME SLICES (PROJECTED) NOT USABLE IN AREAS OF POOR REFLECTION CONTINUITY CUMBERSOME AMPLITUDE CONTROLS POSITION OF TIME SLICE PICKS

  27. PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES DISADVANTAGES TECHNIQUES ADVANTAGES VERY SLOW MANY TIES TRUE 3-D GRID VERY DETAILED MAPS MOST ACCURATE PICTURES OF FAULT PATTERNS HIGHEST CONFIDENCE INTERPRETATION

  28. STRATIGRAPHIC FRAMEWORK ANALYSIS BURIAL HISTORY TRAP DEVELOPMENT AND TIMING MODELING TEMPERATURE HISTORY RESERVOIR PROPERTIES HYDROCARBON GENERATION PREDICTION SOURCE MIGRATION RESERVOIR SEAL TRAP USING A STRATIGRPHIC FRAMEWORK

  29. TECHNIQUES ADVANTAGES DISADVANTAGES MANUAL (SERIAL OVERLAY) WITHOUT TIME SLICES, FEW CROSS LINES MISS STRUCTURES THAT STRIKE SUB-PARALLEL TO LINES INACCURATE 3-D TIES OF HORIZONS & STRUCTURES MAPPING IS ADDITIONAL STEP CUMBERSOME CHEAP NO SPECIAL EQUIPMENT FAST IN STRUCTURALLY SIMPLE AREAS PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES

  30. PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES TECHNIQUES ADVANTAGES DISADVANTAGES MANUAL BUT WITH TIME SLICES (GS) SEISCROP EASY TO RECOGNIZE STRUCTURES IN MOST ORIENTATIONS ACCURATE 3-D TIES OF HORIZONS & STRUCTURES FAST WITH GOOD REFLECTION QONTINUITY EXPENSIVE AND SLOW TO MAKE FILM DIFFICULT TO TIE LINES (PAPER) TO TIME SLICES (PROJECTED) NOT USABLE IN AREAS OF POOR REFLECTION CONTINUITY CUMBERSOME AMPLITUDE CONTROLS POSITION OF TIME SLICE PICKS

  31. PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES DISADVANTAGES TECHNIQUES ADVANTAGES VERY SLOW MANY TIES TRUE 3-D GRID VERY DETAILED MAPS MOST ACCURATE PICTURES OF FAULT PATTERNS HIGHEST CONFIDENCE INTERPRETATION

  32. TECHNIQUES ADVANTAGES DISADVANTAGES CONVERSION OF SEISMIC DATA TO ACCEPTABLE FORMAT CAN BE TIME-CONSUMMING EXCESSIVE DETAIL AVAILABLE ISIS- EPR INTERACTIVE SEISMIC INTERPRATATION SYSTEM ALOWS USE OF ANY TECHNIQUE MOST ACCURATE TIES OF TIME SLICES TO LINES AND LINES TO CROSS-LINES LESS PAPER TO SHUFFLE AMPLITUDE/COLOR SCALING RAPID, ACCURATE DIGITIZING CONTOUR MAPS OF HORIZONS DIGITIZED ON LINES AND/OR SLICES IMAGE MANIPULATIONS ZOOM, STRETCH, SQUEEZE, REVERSE POLARITY RELIEVES INTRPRETATER PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES

  33. SEISMIC-WELL TIES PURPOSE: TO COMBINE TWO DATA SETS FOR A MORE COMPLETE INTERPERATION • SEISMIC DATA • TWO WAY TIME • SEISMIC VELOCITY • SEISMIC IMPEDENCE • SEISMIC SEQUENCES • SEISMIC FACIES • STRUCTURE • WELL DATA • LINEAR DEPTH • VELOCITY • DENSITY • GEOLOGIC AGE • LITHOLOGY • FAULT ORIENTATION

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