12.17.18 WellDatum

Code

WellboreDatumReference

The code value that represents the type of reference datum. This may represent a point on a device (e.g., kelly bushing) or it may represent a vertical reference datum (e.g., mean sea level).

Comment

String2000

A contextual description of the well reference datum.

ExtensionNameValue

ExtensionNameValue

Extensions to the schema based on a name-value construct.

Kind

String64

Because various activities may use different points as measurement datums, it is useful to characterize the point based on its usage. A well reference datum may have more than one such characterization. For example, it may be the datum used by the driller and logger for measuring their depths. Example usage values would be 'permanent','driller', 'logger' 'WRP' (well reference point) and 'SRP' (site reference point).

MeasuredDepth

MeasuredDepthCoord

The measured depth coordinate of this reference datum as measured from another datum. The measured depth datum should either be the same as the elevation datum or it should be relatable to the elevation datum through other datums. Positive moving toward the bottomhole from the measured depth datum. This should be given when a local reference is "downhole", such as a kickoff point or ocean bottom template, and the borehole may not be vertical. If a depth is given, then an elevation should also be given.

Name

String64

The human-understandable contextual name of the reference datum.

uid

String64

A unique identifier for an instance of a well datum.

From: WellDatum.Wellbore

0..1To: RefWellbore

Association

A pointer to the wellbore that contains the reference datum.

This should be specified if a measured depth is given.

From: WellDatum.Elevation

0..1To: WellElevationCoord

Association

The gravity based elevation coordinate of this reference datum

as measured from another datum. Positive moving upward from the elevation datum.

An elevation should be given unless this is a vertical reference datum (e.g., sea level).

From: WellDatum.Rig

0..1To: RefWellboreRig

Association

A pointer to the rig that contains the device used

as a reference datum. The rig may be associated with a wellbore in another well

(e.g., pattern drilling using a rig on a track).

From: WellDatum.

To: WellboreDatumReference

Dependency

From: WellDatum.HorizontalLocation

0..1To: AbstractWellLocation

Association

The horizontal location of the point being used as a well datum.

This may be used when the point is not directly above or below the well point location.

For example, a well being drilled from a platform may have its location at the entrance

into the sea floor, while the well datum may be located on the drilling rig.

Or the well datum may be a kickoff point, that is not directly under the well surface point.

From: WellDatum.Crs

To: AbstractVerticalCrs

Association

From: Well.WellDatum

0..*To: WellDatum

Association