M4 4 Make Zones Layering

Module 4 3D Grid Construction

Make Zones and Layering Objectives 

Isochore processing

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Make Zones and Layering process

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Stratigraphic intervals

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Set parameters for Making zones and Layering

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 Apply adjustments to well tops QC results in 3D.

Processes used for 3D Grid Construction 3D Grid Construction Corner Point Gridding Structural Gridding

Structural Modeling

Fault Framework Modeling Fault Modeling

Structural Gridding

Structural Framework

Pillar Gridding

Make Horizons/Zones/Layers Make Horions/Zones/Layers

Fault Framework Modeling

Horizon Modeling Make Simple Grid

Make Zones: Process  Allows for further refinement of the vertical resolution of the 3D grid. Adds isochores, constants, etc. to the framework to create additional horizons above, below, and between the original horizons. Structural Modeling

Fault Modeling

Pillar Gridding

Make Horizons

Make Zones

Layering

Make Zones: Stratigraphic Intervals 1. Set the Stratigraphic interval. 2. Click Append number of zones and set the input type. 3. Click the Multiple drop icon and insert the isochores from the Input pane. 4. Input well tops if any.

Make Zones: Zones Tab Build from

Volume correction

Build along

Top Horizon Isochores added from top of interval.

Proportional correction Splits the error proportionally into the zones according to relative thickness.

Vertical Thickness (TVT)

Base Horizon  – Isochores added from base of interval.

Equal correction Splits the error into equal proportions for each zone.

Stratigraphic Thickness (TST)

Both Base and Top Horizon  Active only if a Rest zone is defined. (all zones build towards it)

None correction Will not make volume corrections for all zones.

Along Pillar Use when pillars are close to vertical.

Make Zones: Settings Tab Minimum Cell Thickness Sometimes when gridding thin layers, some cells can be defined to have zero thickness. To be able to assign values to these cells, toogle ON the option to define a Minimum cell thickness. Use min. cell thickness to collapse all thin cells less than the given length (project units) to zero thickness.

No min.cell thickness Min.cell thickness Start from Base Min.cell thickness Start from Top

Make Zones: Well Adjustment Tab

1. Make sure the well tops are included as input in the Zones settings. 2. On the Well Adjustment tab, choose Across segment or Inside segment only. Specify the influence radius. 3. Click Apply, and move into the next Stratigraphic interval.

Make Zones: Results

Before

After

Layering: Process Defines the cells of the 3D grid. It is the final vertical subdivision of the framework. The layers are part of the zone but have no direct filter like Zones. Structural Modeling

Fault Modeling

Pillar Gridding

Make Horizons

Make Zones

Layering

Layering: Settings 1. Set the Zone Division (five types). 2. Specify the number of layers (Proportional), cell thickness (Follow top/Base), or relative proportions (Fractions). Proportional 3. (Optional) Input a Reference Surface (e.g., Clinoforms). Follow Base

Follow Top

Fractions

Follow Base with Reference

Layering: Results Types of Zone Division Follow base Proportional Follow top Fractions Follow top + using a depositional surface

Note: It is always a good idea to display edges in 3D to see all updates before applying the Make Zones and Layering processes.

Local Model Update for Structure The Local model update adjusts horizons and layers for selected regions while preserving all 3D properties in all cells. 1. Open the Local model update process and drop in the polygon defining the area to be updated.

2. Drop in the input data to be used to guide the update process. 3. Choose the horizons to recalculate and click Apply.

EXERCISE