Fluid contacts
A fluid contact records the boundary between two fluids inside one zone of the Conceptual Model: an oil-water contact (OWC), a gas-oil contact (GOC), a gas-water contact (GWC) or the free water level (FWL). Contacts are added and edited only in the Conceptual Model panel. They are not used in structural modeling; a constant-level FWL contact can, however, supply the free-water level when applying a Saturation Height Model.
A zone is the interval between two adjacent geological objects and is shown as a Zone row in the tree. Contacts are added to a zone and appear as separate rows beneath it, with the contact type in the Type column. Each assignment that defines a contact is listed as a child row below the contact.
Adding a contact
- Right-click a Zone row and open the Add Contact submenu. On a geological object row, use Add Contact ▸ Zone Above or Add Contact ▸ Zone Below instead.
- Choose the type of the contact: OWC, GOC, GWC or FWL.
The contact is created under the zone and takes its type as name; a second contact of the same type is named OWC (2), and so on. A zone can hold as many contacts as needed – for example one contact per fault block. Right-click a contact and choose Rename to edit its name in place, or Remove Contact to delete it.
Defining a contact
A contact is defined either by a constant level, optionally limited laterally by a polygon, or by a surface. Right-click the contact and use:
- Set Level... – enter the depth of the contact in the Level (depth) field of the dialog that opens.
- Assign Polygon... – choose a polygon that limits the contact laterally, for example to one fault block.
- Assign Map... – choose a depth map that the contact follows, for a tilted or variable contact.
The two options are mutually exclusive: assigning a map clears the level and the polygon, and setting a level or assigning a polygon clears the map. A depth map or a polygon can also be dragged from the Data Manager onto the contact row; other item types are refused with a message.
Each assignment is listed as a child row of the contact, with Level, Polygon or Depth Map in the Type column; a level row shows the depth with its unit. Right-click such a row and choose Change... to select a different value, or Remove to clear it. Maps and polygons are references: the contact points at the item in the Data Manager and does not copy it.
Warnings
A warning icon on a contact row means that the contact needs attention. Point at the row to read the reason:
- No data is assigned yet, so the contact has nothing to draw.
- A referenced Data Manager item is missing, for example because the map or the polygon was deleted. The contact itself is kept, so a new item can be assigned to it.
- The zone changed. When a geological object is removed, the zones above and below it merge, and the contacts of the affected zones move to the merged zone instead of being deleted – check that their definition is still valid.
Showing contacts in the Data Manager
Switch on Show in Data Manager on the Conceptual Model panel title bar to list the contacts in the Data Manager. A Fluid contacts folder appears, with one subfolder per zone and one entry per contact, named after its type and its name. Use the check box of an entry to show or hide that contact in the views. A contact with no data assigned has nothing to draw, so its check box is disabled. The folder is a view of the Conceptual Model and stays in step with it; contacts are still added, renamed and defined in the Conceptual Model panel.
Contacts on sections
A visible contact is drawn as a horizontal line on seismic sections – inline, crossline and arbitrary, in both the time and the depth domain – and on Well correlation view sections, at the depth where the contact crosses each well trajectory.
A contact defined by a level is drawn at that constant depth, and a contact defined by a map follows the map along the section. Where a polygon is assigned, the line is drawn inside the polygon only and breaks outside it. Contacts are defined in depth, so on a time section the line is converted with the project velocity model.
Each contact type has a default colour: OWC blue, GOC green, GWC teal, and FWL blue with a dashed line. In Visual Settings the section overlay is listed as All fluid contacts, with one entry per contact named after its type and its level or map – OWC 2417.0, for example. The colour and the line style of each entry can be changed there.
See Also