Geol 755: Basin Analysis The horizontal section shows a ...crack.seismo.unr.edu/ftp/pub/louie/class/755/data/Louie-power...2 Taken From: Alistair R. Brown, AAPG Memoir 42,Interpretation

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Taken From: Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-Dimensional Seismic Data, 4th & 6th Editions

John N. Louie, Presenter

Stratigraphic InterpretationRecognition of Characteristic Shape

Reconstituting a Depositional SurfaceMethods of Making Horizon Slices

Unconformities

Geol 755: Basin AnalysisGeol 755: Basin AnalysisGeophysics Week 4Geophysics Week 4


Recognition of Characteristic Shape The horizontal section shows a circular area of carbonate buildupThe horizontal section shows a circular area of carbonate buildup


Recognition of Characteristic Shape Circular sinkholes in Circular sinkholes in karstkarst, , Gippsland Gippsland basin, Australiabasin, Australia Clear in horizontal but not vertical sectionsClear in horizontal but not vertical sections


Recognition of Characteristic Shape Bifurcating channel in Gulf of Mexico Chevron dataBifurcating channel in Gulf of Mexico Chevron data

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Recognition of Characteristic Shape Branching channel in Gulf of Mexico Chevron dataBranching channel in Gulf of Mexico Chevron data Summing time slices useful if less than half-cycle of dipSumming time slices useful if less than half-cycle of dip


Recognition of Characteristic Shape Horizontal/vertical composite of Gulf of Thailand dataHorizontal/vertical composite of Gulf of Thailand data


Recognition of Characteristic Shape Horizontal sections of Gulf of Thailand dataHorizontal sections of Gulf of Thailand data

1Taken From: Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-

Dimensional Seismic Data, 4th & 6th Editions

Recognition of Characteristic Shape Horizontal sections of Gulf of Thailand dataHorizontal sections of Gulf of Thailand data

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Recognition of Characteristic Shape Horizontal section of Gulf of Thailand dataHorizontal section of Gulf of Thailand data

3Taken From: Alistair R. Brown, AAPG Memoir 42, Interpretation of Three-

Dimensional Seismic Data, 4th & 6th Editions

Recognition of Characteristic Shape Tidally reworked channels, large & small channelsTidally reworked channels, large & small channels


Recognition of Characteristic Shape Shallow (100 ms) seismic & satellite photo,Shallow (100 ms) seismic & satellite photo, KalimantanKalimantan


Recognition of Characteristic Shape Erosion and Erosion and dendritic dendritic drainage,drainage, KalimantanKalimantan

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Recognition of Characteristic Shape Crossing channels shows a geologic time interval andCrossing channels shows a geologic time interval and

finitefinite section thickness represented assection thickness represented as singlesingle reflection.reflection.


Recognition of Characteristic Shape Can you find the channel on the vertical section?Can you find the channel on the vertical section?


Recognition of Characteristic Shape Mobile, AL offshoreMobile, AL offshore fans as subtle low-amplitude featuresfans as subtle low-amplitude features


Recognition of Characteristic Shape Mobile, AL offshoreMobile, AL offshore fan- dark channels are reservoirsfan- dark channels are reservoirs

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Reconstituting a Depositional Surface We have to follow a reflection to remove post-depositional structure.We have to follow a reflection to remove post-depositional structure.


Reconstituting a Depositional Surface Vertical section showing 3 horizons followed across faultsVertical section showing 3 horizons followed across faults


Reconstituting a Depositional Surface Time-structure map from 3d structure interpretation, reconstructed, amplitude-Time-structure map from 3d structure interpretation, reconstructed, amplitude-

extracted extracted ““shallowshallow”” horizon slice (right) with faults & erosion, sandbar horizon slice (right) with faults & erosion, sandbar 60 m60 mbelow horizon slice.below horizon slice.


Reconstituting a Depositional Surface Top and bottom of channel in stacked horizon slicesTop and bottom of channel in stacked horizon slices

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Methods of Making Horizon Slices

TrackedTrackedhorizon abovehorizon abovebright channelbright channelintersections.intersections.



Horizon sliceHorizon slicewithwithintersectingintersectingchannels,channels, aaconstant timeconstant timebelow anbelow aneasily-tracked,easily-tracked,less interestingless interestinghorizonhorizon


Methods of Making Horizon Slices Elaborations of the horizon-slicing method to work intoElaborations of the horizon-slicing method to work into

areas not easily tracked automaticallyareas not easily tracked automatically



You donYou don’’ttalways snapalways snapto theto themaximummaximumamplitude ofamplitude ofthe newthe newhorizon.horizon.

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Methods of Making Horizon Slices Tracking in Tracking in vertvert. section,. section, time-time-

structure map, amplitude horizonstructure map, amplitude horizonslice slice w/ w/ reconstructed channelreconstructed channel


Methods of Making Horizon Slices Continuity in horizon slice shows proper trackingContinuity in horizon slice shows proper tracking


Methods of Making Horizon Slices Amplitude horizon slice with structure contours shows gas in highsAmplitude horizon slice with structure contours shows gas in highs


Unconformities Amplitude horizonAmplitude horizon

slice with structureslice with structurecontourscontoursdistinguishes faultsdistinguishes faultsfrom bed truncationfrom bed truncation

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Unconformities Horizon slice showing Horizon slice showing nearshore paleodrainage nearshore paleodrainage ending at shorelineending at shoreline


Unconformities Lisburne Lisburne 3D vertical section,3D vertical section, Prudhoe BayPrudhoe Bay


Unconformities Amplutude Amplutude horizonhorizon slice along slice along Lisburne Lisburne Lower Cretaceous UnconformityLower Cretaceous Unconformity

(LCU) with NW-SE (LCU) with NW-SE lineationslineations..


Unconformities NW-SE LCU NW-SE LCU lineations lineations interpreted as truncations of reservoir rocks.interpreted as truncations of reservoir rocks.

Documents

Geol 755: Basin Analysis The horizontal section shows a ...crack.seismo.unr.edu/ftp/pub/louie/class/755/data/Louie-power...2 Taken From: Alistair R. Brown, AAPG Memoir 42,Interpretation