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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. FAULT RECOGNITION • ABRUPT TERMINATION OF REFLECTION • OFFSET OF A REFLECTION • DIFRACTION • CHANGE IN RELECTION PATTERN • CHANGE IN DIP • CHANGE IN FREQUENCY • DISTORTION OF DATA BELOW FAULT • - VELOCITY ANOMALY • - SHADOW ZONE • REFLECTION FROM FAULT PLANE

  6. NORMAL FAULTS • HORST AND GRABEN • TILTED BLOCKS • HIGH ANGLE SAMPLE FAULTS • UNCONFORMITY ON PRE-FAULT SEDIMENTS • STRUCTURES ANGULAR IN CROSS SECTION • FAULTS DIP TOWARD UPLIFT • DRAPE COMMON • DRAG ON DOWNSIDE OF FAULTS • FAULTS RELAY, ZIG-ZAG IN MAP VEIW • DIFRACTIONS ON DOWNSIDE OF FAULTS • OFTEN HIDDEN BY OVERLYING STRUCTURE KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 1/10

  7. UPTHRUST FAULTS • FAULT FORMS ZONE OF INTENSE DEFORMATION • BLOCKY AWAY FROM FAULT • FAULT IS HIGH ANGLE - MAY SPLIT OUT • ONE PERIOD OF MOTION • STRUCTURES PARALLEL FAULTS • STRUCTURES ANGULAR IN CROSS SECTION • GRAVITY AND MAGNATIC EXPRESSION PROBABLE

  8. EN ECHELON FOLDS AND FAULTS • STRUCTURES AT ANGLE TO THRUOGH-GOING FAULTS • STRUCTURES ASYMMETRICAL • ANTICLINES PREDOMINATE • FAULT-STRUCTURE RELATION CHANGES LINE TO LINE • FAULTS VERY HIGH ANGLE • FAULTS SPLY UPWARD INTO SHALLOWER BEDS • THROUGH-GOING FAULT GENERALLY NOT SEEN • EXTENSIONAL FAULTS MAY DEVELOP ON CRESTS • GRAVITY AND MAGNETICS MAY SHOW

  9. FLOWER STRUCTURES • PARALLEL THROUGH-GOING FAULT • DIE OUT DOWNWARD • COMPOSED OF COMPLEX PATTEN OF ABERRANT WEDGES • FAULTS NEARLY VERTICAL BUT SPLAY OUT UPWARD • STRUCTURE -FAULT RELATION CHANGES LINE TO LINE • STRUCTURING DIES OUT ABRUPTLLY • ANTICLINES PREDOMINATE • DIFRACTIONS COMMON • GRAVITY AND MAGNATICS MAY SHOW

  10. FOLD AND THRUST BELT ROLES • COMPRESSIONAL AND DETACHED • DOMINANT VERGENCE DIRECTION • OUTWARD DEVELOPMENT OF THRUST SHEEETS • THRUSTS OUT UPSECTION IN DIRECTION OF TRANSPORT • THRUST BRING OLDER ROCKS OVER YOUNGER ROCKS • EXISTENCE OF PREFERRED DETACHMENTS IN SECTION • EXISTENCE OF A REGOINAL TECTONIC LEVEL

  11. COMPATIBILITY WITH GRAVITY DATA A GEOLOGICAL MODEL THAT IS COMPATIBLE WITH THE OBSERVED GRAVITY DATA IS POSSIBLY CORRECT. A GEOLOGICAL MODEL WHOSE GRAVITY EXPONSE DISAGREES WITH THE OBSERVED GRAVITY DATA IS DEFINITELY WRONG.

  12. PASSIVE MODE SALT DOES NOT ACTIVELY DEFORM SEDIMENT. MOST FEATURES ARE ATTRIBUTED TO SALT WITHDRAWAL. ACTIVE MODE SALT ACTIVELY PUSHES SEDIMENT COVER OUT OF THE WAY AS I TRIES TO RISE TO THE SAE FLOOR.

  13. VERTICAL MOTION • FORCE • DEFFERENTIAL LOADING OR DENSITY DIFFRENCES RESULTANT SALT DOMES SALT DIAPIRS SHALE DOMES

  14. SALT STRUCTURES INTRODUCTION TYPES OF STRUCTURES AND TRAPS 1. CLASSIFICATION 2. VARIATIONS DUE TO GROWTH HISTORY 3. DETACHED NORMAL FAULTS SEISMIC INTERPRETATION 1. REFLECTION QUALITY 2. INTERNAL SEISMIC CHARACTER OF SALT 3. WHAT TO USE WITHOUT SALT REFLECTION 4. DOME WITH SHADOW DOME 5. INTERPRETATION PROBLEMS

  15. NON PIERCEMENT PIERCEMENT HORIZANTAL ACTIVE (1-SIDED?) DOME OR WALL ACTIVE PILLOW OR ANTICLINE SILL INTRUSIVE ACTIVE IMPLACEMENT PROCESS PASSIVE (RESIDUAL) PILLOW OR ANTICLINE PASSIVE DOME OR WALL GLICIER (EXTRUSIVE) PASSIVE SALT FEATURE

  16. SUMMARY OF HYDROCARBONE TRAPS RELATED TO SALT PILLOW • A TRAP IS A DOUBLY-PLUNGING ANTICLINE • STRTIGRAPHIC COMPLICATIONS ONLAP, LOSS OF SECTION ON TO CREST VARATION BETWEEN FAULT BLOCKS • STRUCTURAL COMPLICATIONS COMPLEX TRAP SEGMENTATION BY FAULTS FAULT SEAL

  17. EPSODIC VS CYCLIC DEPOSOTION 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 32/60

  18. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 33/60

  19. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 34/60

  20. GENERATING FEATURE TIME-STRATIGRAPHY UNCONFORMITIES YES YES SEPARATES OLDER STRATA BELOW FROM YOUNGER STRATA ABOVE STRATAL SURFACES REFLECTION AND TIME-STRATIGRAPHY KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 35/60

  21. 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) KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 36/60

  22. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 37/60

  23. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 38/60

  24. LIMITATIONS RESOLUTION • VERTICAL • LATERAL IMPROPER POSITIONING REFLECTIONS • DIP ANALOG SECTION • OUT-OF-PLANE REFLECTION NONPRIMARY REFLECTIONS • NONCOHERENT NOISE • COHERENT NOISE KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 39/60

  25. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 40/60

  26. REFLECTION GEOMETRIES REFLECTION CHARACTERISTICS LOG ANALYSIS CORE ANALYSIS CALIBRATION INTERPRETATION FACIES MODEL DEPOSITIONAL ENVIRONMENT SEDIMENT SUPPLY PRIDICTION SEISMIC FACIES ANALYSIS APPROACH SEISMIC FACIES ANALYSIS KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 41/60

  27. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 42/60

  28. REFLECTION GEOMETRIES • TERMINATION PATTERN • INTERNAL CONFIGRATION • EXTERNAL FORM REFLECTION CHARACTERISTICS • AMPLITUDE • CONTINUITY • FREQUENCY INTERVAL VELOCITY SEISMIC FACIES PARAMETERS KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 43/60

  29. REFLECTION GEOMETRIES INTERNAL CONFIGURATIONS UNSTRATIFIED STRATIFIED SIMPLE PROGADATIONAL COMPLEX CHAOTIC REFLECTION FREE • SEGMIOD • OBLIQUE • COMBINATION • SHINGLED • MOUNDED • HUMMOCHY • DEFORMED • BARALLEL • SUBPARALLEL • DIVERGENT KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 44/60

  30. REFLECTION GEOMETRIES EXTERNAL FORM UNIFORM THICKNESS VARYING THICKNESS • SHEET-EVEN • SHEET-DRAPE • SHEET-SMOOTHING • FILL • MOND • COMBINATION KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 45/60

  31. EROSION TOPLAP CONCODANT ONLAP DOWNLAP CONCORDANT PARALLEL SUBPARALLEL DIVERGENT SIGMOID OBLIQUE SHINGLED MOUNDED HUMMOCKY DEFORMED GEOMETRIC PARAMETERS ABC TECHNIQUE KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 46/60

  32. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 47/60

  33. AMPLITUDE CONDITIONS LITHOLOGY UNIFORM ALTERNATING VARYING MASSIVE INTERFINGERED DISCONTINUOUS LOW HIGH VARIABLE CONTINUITY DEPOSITION HIGH WIDESPREAD REFLECTION CHARECTERISTICS AND DEPOSITIONAL ENERGY KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 48/60

  34. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 49/60

  35. VISUAL SEISMIC SIGNATURES OF HYDROCARBON INDICATORS • AMPLITUDE ANOMALY • FREQUENCY ANOMALY • TIME SAG • ABRUPT TERMINATIONS • PHASE CHANGE • FLUID CONTACT REFLECTION • SHADOW ZONE • CHINMEY KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 50/60

  36. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 51/60

  37. TECHNIQUES DISADVANTAGES MISS STRUCTURES THAT STRIKE SUB-PARALLEL TO LINES INACCURATE 3-D TIES OF HORIZONS & STRUCTURES MAPPING IS ADDITIONAL STEP CUMBERSOME MANUAL (SERIAL OVERLAY) WITHOUT TIME SLICES, FEW CROSS LINES PRELIMINARY EVALUATION 2-D INTERPRETATION TECHNIQUES ADVANTAGES CHEAP NO SPECIAL EQUIPMENT FAST IN STRUCTURALLY SIMPLE AREAS KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 52/60

  38. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 53/60

  39. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 54/60

  40. PRELIMINARY EVALUATION 3-D INTERPRETATION TECHNIQUES TECHNIQUES ADVANTAGES DISADVANTAGES CONVERSION OF SEISMIC DATA TO ACCEPTABLE FORMAT CAN BE TIME-CONSUMMING EXCESSIVE DETAIL AVAILABLE INTERACTIVE SEISMIC INTERPRETATION 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 55/60

  41. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 56/60

  42. 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 KFUPM/ES/Geophysics/Seismic Interpretation/Al-Ghamdi # 57/60

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