Terms and Concepts

The property 'resistivity' might be defined as having meaning 'the electrical resistance offered to the passage of current', the range 'quantity expressed in ohm-meters', and the domain 'material'. [example adapted from PIDD]
The POSC property type definitions include both 'object' properties (which imply a specific object) and 'pure' properties (which imply a general class of object).

At the top of the POSC property hierarchy are a number of 'pure' properties, which are specialized to other pure properties, which may be further specialized to object properties. In some cases object properties may be further specialized (typically not by means of object domain specialization).
For consistency, the following rules would seem to apply:

• If the domain of the parent is specified, the domain of the sub-property is either the same domain or a restriction of it (more specifically, an 'pure' property may not be a sub-property of an 'object' property).
• The subdivision of an 'object' property should be limited to the case where the domain is a restriction of the parent domain.
• If the range of the parent is specified, the range of the sub-property is either the same range or a restriction of it.

The following curve class attributes are defined: Object, Technique, Property, Modifier_A, Modifier_b, Function

attribute [TXT][XML][HTML]

keyword [TXT][XML][HTML]

Typically the tool class, for curve classes which are associated with a specific tool class. 'Utility' curve classes (caliper, cable tension, ...) are typically not broken out by tool class, in which case this attribute is omitted.

This attribute is applied at the curve instance level because curve classes are not broken out by distinct dimensionality. This is consistent with DLIS identifier dictionary-control principles: curve and parameter mnemonics are not bound to a specific dimensionality, and binding curve classes to dimensionality might unnecessarily expand the population of curve classes, and might require multiple classifications per curve mnemonic.

========
Values:
--------
TIME_INT  - time interval
...
========

The object domain is typically a class of material in the logging environment (formation, invaded zone, borehole fluid, ...), or a class of equipment (loggin tool, logging cable, ...), or a class of process (computation, ...) or a class of activity (logging cable movement, ...).

well_log_curve_class [TXT][XML][HTML]

property_type [TXT][XML][HTML]

well_log_service_class [TXT][XML][HTML]

well_log_tool_class [TXT][XML][HTML]

For downhole logging instruments, a tool series designation is typically used, e. g. 'CDM'. In other cases a general (but still company-defined) designation is typical, e. g. 'bridle', 'surface system'.

well_log_tool_series [TXT][XML][HTML]