POSC PWLS V1.0 Reference Data Release

POSC Practical Well Log Standards

A Standard for Well Log Curve Naming  

Release History
Version 1.0.127-Feb-2001PWLS Project, Phase I Results (corrected)
First formal release (corrected).
Version 1.0 22-Feb-2001 PWLS Project, Phase I Results 
First formal release. Withdrawn on 26-Feb-2001 due to an error.

Quick Access to the Specifications

Tools Addressed

Version 1.0 addresses approximately 60 types of high visibility tools in current use from these categories.

List of tools addressed in the Version 1.0 release.

Other Resources

Background

Defining a PWLS standard was motivated by several well log management business issues:

Work on PWLS will establish and communicate standards to address these issues for use throughout the industry by:

Generic Tool Names

Tool names for acquisition data will maintain their full technical and marketing names. Generic tool names (tool types) are being defined to be understandable to all and to remain consistent over time. Specific tool string names will be created by concatenating component tool names. 

Consider these Tool Type examples:

Tool Types Tool Type Descriptions
ARES Array Resistivity
ASON Array Sonic
CAL Caliper
DEN Density
DEN.NEU Density/Neuron
DIP Dipmeter
ELEM Element
IMG Imaging
PERF Perforating
PRES Pressure

Generic Curve Names

For company-specific curve names, the service company mnemonics are retained. Phase I attempted to define generic, cross-vendor curve names to increase understandability and ease of handling in processing and data management activities. Two candidate forms of generic curve names were realized, but there wasn't an agreement that either or both forms were best suited to become the form of the industry-standard curve names. Pending further consideration, both forms are provisionally presented in Version 1.0 specifications. 

One Phase I generic curve name form is derived from the leaf nodes of a general-purpose property type classification hierarchy, the Schlumberger OSDD Property Type, This form is currently called Property Type. 

The other Phase I generic curve name form is composed as mnemonic token sequences where the mnemonics represent attributes of the curve describing the object measured (default: formation), the measurement technique (default: basic log measurement), the measurement obtained, qualifiers on the measurement process (default; none), and the quantity derived from the measurement (default: no derivation). This form is currently called Curve Type.

Consider these examples from Version 1.0:

Baker Atlas Curve Mnemonics Halliburton Curve Mnemonics Schlumberger Curve Mnemonics Phase i Curve Types Phase I Property Types
ATT1, ATT2, ... .  LSA1, LSA2, .. AC.AMP. Acoustic_Amplitude
    ISSA, STIK, ... AC.DTD. Sonic_Data_Density
CAL, CALX, ... HSI, SDK2, ... LCAL, RLCA, ... CAL. Caliper
    DCAL CAL.DIF Differential_Caliper
M2C1, M2C2, ...   AIBC, AIFC, ... CON.ARR.IND. Induction_Array_Conductivity
CLLD, CTBR   CLLD CON.DEP.LAT. Deep_Laterolog_Conductivity
BDCM, BDCX, ... RHOB, BD2, ... HDEB, HRHL, ... DEN. Bulk_Density

Reading Guide

The following table is useful in reading the PWLS standard from the V1.0 spreadsheets.

Spreadsheet

 Column Description
Tools Company Code Reference Entity originally developed by the API, maintained by POSC, identifies, with a numeric code, the service company that defines and uses each tool.
  Company Name Text name for the service company that defines and uses each tool.
  Tool Code or Model Company provided tool designation including series and/or version. Options are separated by commas.
  Tool Group or Series Company provided tool series/group designation (without version id)
  Tool Marketing Name Company provided common tool name
  Tool Description Company provided text tool description.
  Tool Type PWLS defined, textual mnemonic, generic industry standard tool designation called tool type.
  Tool Type Description Text description for a tool type.
  Tool Logging Method Industry standard reference value identifying the logging method used by the tools of a tool type, e.g., wireline, LWD.
  Company Curve Mnemonic Company provided channel (curve) identification. [Channel data appears on a row with each tool that records that channel. Whereas channel is the mechanism that records, a curve is that which is recorded by a tool channel in one run or pass.]
  LIS Curve Mnemonic Company provided tool - channel identification for use in LIS format files. This mnemonic, limited to four characters, is shown only where it is different from Company Curve Mnemonic.
  Company Curve Description Company provided text channel description.  
  Curve Business Value PWLS defined, industry standard reference value indicating the relative importance of (generic) curves for general purpose usage. Reference values are High, Medium, and Low. 
  • High Value Curves are needed for most everyday purposes, i.e., curves loaded to long-term storage for future use by petrophysicists. 
  • Medium Value Curves are those needed occasionally. 
  • Low Value Curves are those not normally used by oil companies, e.g., diagnostic curves, basic physical measurements (voltages), even if they are routinely used by service companies, e.g., for calibration. [Low Value Curves are not assigned industry standard curve names. Implicitly, these are considered to be classified as Auxiliary Curves. These curves are usually stored in original format files, e.g. DLIS, LIS.]
  Phase I Curve Type PWLS defined generic curve designation composed as a mnemonic token sequence, where the mnemonics represent attributes of the curve describing the object measured (default: formation), the measurement technique (default: basic log measurement), the measurement obtained, qualifiers on the measurement process (default; none), and the quantity derived from the measurement (default: no derivation). Each component mnemonic is followed by a period (.), e.g. AC.SLO. and DEN.QUAL. This can be used as a simple query criteria when searching data collections. There are issues with some of the Phase I Curve Types that may result in modifications during Phase II.
  Phase I Property Type PWLS defined generic property classification leaf node corresponding to a generic curve designation. This is derived from the leaf nodes of a general-purpose property type classification hierarchy, the Schlumberger OSDD Property Type. It is made up of a sequence of words separated by the underscore (_) character. This designation can be used in conjunction with the full Classification Hierarchy path as a navigation aid or search criteria. There are issues with some of the proposed additional Property Type leaf nodes defined in Phase I. These will be reconsidered during Phase II.
  Unit Type PWLS assigned generic unit of measure designation associated with this generic curve designation, including those produced by this tool - channel. This can be used to augment the description of the curve and associated data or as a query criterion.
Classification Phase I Property Type Leaf Node Leaf node of the Phase I Property Type classification hierarchy. (See above.)
  Phase I Curve Type Mnemonic String Phase I Curve Type. (See above.) corresponding to a leaf node.
  Phase I Property Type Classification Hierarchy (Paths) Property Type classification with lower level nodes shown below and to the right of parent nodes. Thus, sibling nodes are shown below each other.
Last update: February 11, 2001. Copyright © 2001 Petrotechnical Open Software Corp. All Rights Reserved.