wheeler diagram and interpretation of wheeler diagram

WHEELER DIAGRAM&

ITS USES IN EXPLORATIONAND EXPLOITATION IN

HYDROCORBONS

Presented by: Awais Ayub Awan Muhammad Umar

Muhammad Sajid

Presented to: Mr. Abdul Hannan

Group # 4

Wheeler Diagram Harry Eugene Wheeler ( History to Wheeler

diagram) Integrated data of Wheeler Diagram Application of Wheeler diagram in Exploration

and hydrocarbon exploitation Wheeler Diagrams related to base level changes,

system tracts, stratigraphic surfaces, Unconformity

Wheeler diagram of a fluvial to shallow-marine depositional sequence(Dip oriented stratigraphic succession)

Contents

Interpretation of Wheeler diagram of a fluvial to shallow-marine depositional sequence

Wheeler diagram on the base of well log data

(Pseudo Wheeler diagram)Calibration through Pseudo wheeler diagram

workflow for interpretation of Pseudo Wheeler Diagram

Geohistory diagram and location of well data

Application of Pseudo wheeler diagram

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wheeler diagram related to interpretation of Coastal onlap curve

Wheeler transformation ( seismic based wheeler diagram

Uses of Wheeler diagram Conclusion References

A stratigraphic summary chart on which geologic time is plotted as the vertical scale, and distance across the area of interest as the horizontal scale, and on which a variety of stratigraphic information is brought together.

Display both the horizontal distribution of the contemporaneous component sedimentary layers of a sequence but also the significant hiatuses in sedimentation. 

Wheeler Diagram

Stratigraphic summary chart It’s a spatio-temporal diagram Consist of x-axis and y-axis On x-axis plot distance of stratigraphic area

of interest On y-axis plot Geologic age ( absolute and

relative) of stratigraphic section

Wheeler diagram

On the cross section above the A5 surface is truncated by an unconformity but on this area-time plot of Wheeler (1964) the A5

surface extends across the entire region, with a large portion of it is within the lacuna domain

Wheeler diagram

American Geologist and Stratigraphic (1907 – 26 January 1987) A professor of geology at the University of

Washington from 1948 until 1976 Wheeler's work in the 1950 and 1960s was

pivotal in the later development of sequence stratigraphy

still used today, for example by Petroleum industry

Harry Eugene Wheeler 

His 1964 paper, Baselevel, Lithosphere Surface, and Time-Stratigraphy evolved the concept of base level

   To emphasize the continuous spatial and

temporal nature of stratigraphy, eventually giving rise to wheeler diagram.

Harry Eugene Wheeler

The contemporaneous component sedimentary layers 

Systems tracts of sequences in terms of their relationship to baselevel, hiatuses, timing and geographic location. 

Wheeler diagrams enable the analysis of a stratigraphic section

Outcrops dataCore dataWell logsSeismic data

Integrated data of Wheeler Diagram

Base level change Interplay between base level change and

sedimentation Interpretation of sedimentary environment Stacking pattern (Progaradation &

retrogradation) System tracts Sequences Surfaces

Application of Wheeler diagram

Unconformity Deposition Condensation Erosion Hiatus Hydrocarbon exploration Economic minerals Geologic time and thickness of formation Geographic distance of stratigraphic

succession

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Depositional patterns during a full regressive-transgressive cycle

Base level Change

For the stratal stacking patterns of the four systems tracts

Their inferred timing relative to the base-level curve

Above Wheeler diagram illustrate

Subaerial unconformity extends basinward

Due to forced regression of the shoreline

correlative conformity meets the basinward termination of the subaerial unconformity

Appearance of fluvial onlap depends on topographic gradients

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Grading trends (fining- vs. coarsening-upward) are temporally offset between shallow- and deep-water systems

Progradation of basin-floor fans continues throughout the regressive stage

onset of base-level rise marks a change from high-density to low-density turbidity currents

sand starts to be trapped

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aggrading fluvial to coastal systems during lowstand normal regression

stratal architecture breakdown of a sequence into the four systems tracts

A full cycle of base-level changes consists of a succession of four distinct stages of shoreline shifts

(i.e., two normal regressions, one transgression and one forced regression)

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Its logic in separating the products of deposition of four stages in the evolution of a sequence

Each stage of shoreline shift is associated with different economic opportunities

i. Petroleum plays, ii. Exploration strategiesiii. change markedly between the products of

forced regression and subsequent lowstand normal regression.

Correlative conformity marked the end of regression and base level fall

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Wheeler diagram of a fluvial to shallow-marine depositional sequence(Dip oriented stratigraphic succession)

(1)Fluvial to shallow-marine depositional sequence

(2) Wheeler diagram

based on the Upper Cretaceous succession in southern Utah,

End of the estuary life time (end of transgression) is accompanied by an abrupt shift in fluvial styles upstream

It recognize nonmarine portion of the maximum flooding surface.

Interpretation of Wheeler diagram of a fluvial to shallow-marine depositional sequence

Landward shift of facies through time

Boundary between braided and meandering stream facies

Fining upward trend within the fluvial part of each systems tract.

Threshold of facies shift across the maximum flooding surface

Maximum flooding surface in fluvial successions indicated by an abrupt increase in fluvial energy, from meandering to overlying braided fluvial systems

End estuary life time triggers a rapid seaward shift of the river mouth ( delta)

Maximum flooding surface is indicated by a grain size.

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Wheeler Diagram interpreted on the base of Well log data

Calibration through a 'pseudo Wheeler' diagram

A review of depositional episodes Tectonic/ Eustatic gaps, Allowing identification of correlations The relevance of the sea level curve

Pseudo Wheeler Diagram

1. Lithology

2. Sequence Stratigraphy

3. Environments and Facies

4. Lithostratigraphy

5. Chronostratigraphy

workflow for interpretation of Pseudo Wheeler Diagram

Geohistory diagram and location of well data

Pseudo Wheeler Diagram

Pseudo Wheeler Diagram

Identification of depositional episodes and Environments

Evaluation of tectonic/ eustatic gaps

Allowing identification of correlations

The relevance of the sea level curve

Petroleum play

Application of Pseudo Wheeler Diagram

Dip oriented stratigraphic succession and relationships of the facies and the ‘coastal’ onlap curve

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Wheeler Diagram of Dip oriented stratigraphic succession and relationships of the facies and the ‘coastal’ onlap curve

Coastal onlap curve ‘Coastal’ onlap curve is use in the seismic and

sequence stratigraphy for the construction of the global cycle chart.

Composed mainly of a combination of fluvial and marine onlap.

‘Coastal’ onlap indicates stages of sea-level rise is misleading, and resulted in

the representation of sea-level fall as instantaneous events.

Wheeler transform is the seismic equivalent of the geologic Wheeler diagram.

Flatten the seismic data (or derived attributes) along flattened chrono-stratigraphic horizons.

The vertical axis in the Wheeler transformed domain is relative geologic time (as opposed to absolute geologic time)

Wheeler transform can be performed in 2D and 3D

Wheeler Transformation

Purpose; To flatten the seismic data while honoring

hiatuses caused by non-deposition and erosion.

Work flow; i. Select a pre-calculated chrono-stratigraphy

ii. Add a Wheeler scene and use the selected chrono-stratigraphy to flatten the seismic data (or attribute).

Wheeler Transformation

Wheeler Transformation

Wheeler diagram on base of seismic data

Wheeler diagrams provide a useful tool for hydrocarbon exploration when it used in junction with sequence stratigraphic principles.

Reservoir risks can be significantly reduced by using such charts

It use with sequence stratigraphic depositional models to identify potential sand-prone facies.

Conclusions and Uses

Interpretation of sedimentary environment Stacking pattern (Progaradation &

retrogradation) Unconformity Economic minerals

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Principle of Sequence stratigraphy by Octuvian Catuneanu

Sequence stratigraphy by Emry Web search Google Books Google Imageswww.wikipedia.comwww.geology.comwww.scl.comStrata terminology site

Refrences

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