DLIS-RP66-PART-8

Part 8: DLIS Schema

Edition 1

Using the methodology outlined in Part 1, this part describes the Digital Log Interchange Standard (DLIS) schema, namely the collection of object types administered by the Subcommittee On Recommended Format For Digital Well Data using organization code 66. It includes object types useful for recording well log data.

- Definitions

Changes to the DLIS schema are recommended by the Subcommittee On Recommended Format For Digital Well Data and approved by POSC. Changes may include addition of new object types, addition of new attributes to existing object types, changes to the restrictions on existing attributes, or removal of attributes or object types. An attribute or object type removed in one edition may be restored in a later edition only if restored with its previous meaning. A new edition of the basic schema occurs when approved by POSC, and has an edition number obtained by adding 1 to the previous edition number.

The intent is to maintain as much consistency as possible between editions. The principle motivation for a new edition should be to add new object types or attributes. However, from time to time compelling reasons arise for removing items because they are unused or impose unreasonable burdens on users and implementations.

As stated in Part 1, a schema is a collection of object types specified and administered by an organization. The schema is identified by an organization code (see Appendix A). The object types support writing data of interest to the organization and reflect a data model adopted by the organization, whether explicitly or implied.

The data model represented by the DLIS schema is implied by the descriptions of the object types given in this part. The DLIS schema provides the following object types:

• CALIBRATION, used to identify the collection of measurements and coefficients that participate in the calibration of a channel.
• CALIBRATION-COEFFICIENT, used to record coefficients, their references and tolerances used in the calibration of channels.
• CALIBRATION-MEASUREMENT, used to record measurements, references, and tolerances with which calibration coefficients are computed.
• EQUIPMENT, used to describe an item of surface or downhole equipment used in the acquisition of data.
• DLIS-CONTEXT, used to establish a context for the data related to a particular origin.
• MESSAGE, used to write a textual message tied to other data by means of a time stamp and other indexing attributes.
• PATH, used to identify channels that represent the coordinates of a path along which a logging tool string may pass and to specify certain geometric features of the tool string relative to the path.
• SPLICE, used to identify the component channels of a splice and the splice points.
• TOOL, used to record information about a logging tool and its component equipment parts.
• WELLBORE-PATH-DATUM, used to record the location of a wellbore path datum (see 2.40).

In this part, any unit expressions used in unit restrictions belong to the API-SI unit model corresponding to organization code 0 (zero).

The following object types are required to have dictionary-controlled identifiers (see Part 2):

• TOOL

Use of any attribute is considered optional unless otherwise stated. More stringent requirements on presence of attributes is delegated to content standards, which are not part of this document.

Attributes DESCRIPTION and EXTENDED-ATTRIBUTES are used in all object types as specified in the RP66 basic schema (see Part 6).

A CALIBRATION object identifies the collection of measurements and coefficients that participate in the calibration of a channel Figure 2 - llustration of simple two-point linear calibration

Table 1 - CALIBRATION Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	CALIBRATED-CHANNELS	r=OBNAME, u=
2	UNCALIBRATED-CHANNELS	r=OBNAME, u=
3	COEFFICIENTS	r=OBNAME
4	DATE	c=1, r=DTIME, u=
5	MEASUREMENTS	r=OBNAME, u=
6	PARAMETERS	r=OBNAME, u=
7	METHOD	c=1, r=IDENT | TIDENT, u=, v=(see note)

*Notes:

CALIBRATED-CHANNELS is a list of names of CHANNEL objects. The corre- sponding channels (typically just one) are declared to be calibrated using the coefficients and measurements identified by the COEFFICIENTS and MEASUREMENTS attributes.

UNCALIBRATED-CHANNELS is a list of names of CHANNEL objects. The corresponding channels (typically just one) are used, along with coefficients and according to the computational method, to compute the channels identified by the CALIBRATED-CHANNELS attribute.

COEFFICIENTS is a list of names of CALIBRATION-COEFFICIENT Objects. The coefficients, references, and tolerances collectively defined by these objects are used to compute the channels identified by the CALIBRATED-CHANNELS attribute.

DATE is the date the coefficients were computed.

MEASUREMENTS is a list of names of CALIBRATION-MEASUREMENT objects. The measurements collectively defined by these objects are used to derive the coefficients that are used to calibrate the channels identified by the CALIBRATED-CHANNELS attribute.

PARAMETERS is a list of names of PARAMETER objects. The referenced objects provide information directly associated with the calibration process, for example statistics, quality control indicators, parameters entered by the operator, vendor-supplied coefficients, and other information (numeric or textual) that is potentially of interest to the consumer.

METHOD is a reference value that defines the computational method used to calibrate the channels identified by the CALIBRATED-CHANNELS attribute. There are currently no reference values defined under the DLIS schema.

A CALIBRATION-COEFFICIENT object is used to record coefficients, their references and tolerances used in the calibration of channels.

Table 2 - CALIBRATION-COEFICIENT Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	LABEL	c=1, r=IDENT | TIDENT, u=, v=(see note)
2	COEFFICIENTS	-
3	DIMENSION	r=ULONG, u=
4	AXIS	r=OBNAME, u=
5	REFERENCES	-
6	PLUS-TOLERANCES	-
7	MINUS-TOLERANCES	-

*Notes:

LABEL is a reference value that identifies the role of COEFFICIENTS in the calibration process. There are currently no reference values defined under the DLIS schema.

COEFFICIENTS is an array of coefficients corresponding to LABEL.

DIMENSION applies to COEFFICIENTS, REFERENCES, PLUS- TOLERANCES, and MINUS-TOLERANCES (For DIMENSION usage, see Part 6, Basic Schema.)

AXIS applies to COEFFICIENTS, REFERENCES, PLUS-TOLERANCES, and MINUS-TOLERANCES (For AXIS usage, see Part 6, Basic Schema.)

REFERENCES is an array of references corresponding to COEFFICIENTS. Each REFERENCES element represents in some sense the nominal value of the corresponding COEFFICIENTS element.

PLUS-TOLERANCES is an array of tolerances corresponding to COEFFICIENTS. Each PLUS-TOLERANCE element indicates by how much the corresponding COEFFICIENTS element may exceed its reference and still be "within tolerance". Elements shall be non-negative numbers. A coefficient is within tolerance if it is less than or equal to its reference plus its plus tolerance. If this attribute is absent, then infinite plus tolerance is assumed.

MINUS-TOLERANCES is an array of tolerances corresponding to COEFFICIENTS. Each MINUS-TOLERANCE element indicates by how much the corresponding COEFFICIENTS element may fall short of its reference and still be "within tolerance". Elements shall be non-negative numbers. A coefficient is within tolerance if it is greater than or equal to its reference minus its minus tolerance. If this attribute is absent, then infinite minus tolerance is assumed.

A CALIBRATION-MEASUREMENT object is used to record measurements, references, and tolerances with which calibration coefficients are computed.

Table 3 - CALIBRATION-MEASUREMENT Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	PHASE	c=1, r=IDENT | TIDENT, u=, v=(see note)
2	MEASUREMENT-SOURCE	c=1, r=OBJREF, u=
3	TYPE	c=1, r=IDENT | TIDENT, u=, v=(see note)
4	DIMENSION	r=ULONG, u=
5	AXIS	r=OBNAME, u=
6	MEASUREMENT	-
7	SAMPLE-COUNT	c=1
8	MAXIMUM-DEVIATION	-
9	STANDARD-DEVIATION	-
10	BEGIN-TIME	c=1
11	DURATION	c=1
12	REFERENCE	-
13	STANDARD	-
14	PLUS-TOLERANCE	-
15	MINUS-TOLERANCE	-

*Notes:

PHASE is a reference value indicating what phase in the overall job sequence is represented by the current measurement (see Part 9).

MEASUREMENT-SOURCE references an object that specifies the source of the data recorded in MEASUREMENT.

TYPE is a reference value that specifies the type of measurement taken. Currently there are no reference values defined under the DLIS schema.

DIMENSION applies to MEASUREMENT, MAXIMUM-DEVIATION, STANDARD-DEVIATION, REFERENCE, PLUS-TOLERANCE, and MINUS- TOLERANCE. (For DIMENSION usage, see Part 6, Basic Schema.)

AXIS applies to MEASUREMENT, MAXIMUM-DEVIATION, STANDARD- DEVIATION, REFERENCE, PLUS-TOLERANCE, and MINUS-TOLERANCE. When present, its count shall match DIMENSION count. (For AXIS usage, see Part 6, Basic Schema.)

MEASUREMENT consists of one or more values, each described by DIMENSION, and each representing one measurement sample related to the uncalibrated data and described by TYPE. The number of values in MEASUREMENT is its count divided by the size in elements of a value described by DIMENSION. The measurement may represent values of, an average of, or some other function of the uncalibrated data.

SAMPLE-COUNT is the number of measurement values used to compute MAXIMUM-DEVIATION and STANDARD-DEVIATION.

MAXIMUM-DEVIATION is meaningful only when MEASUREMENT contains a single sample value. In this case, the measurement is considered to be a mean, and MAXIMUM-DEVIATION represents the maximum deviation from this mean of any sample used to compute the mean. For arrays, the mean and maximum deviation are computed independently for each element. The deviation for any element from the mean is computed as an absolute value.

STANDARD-DEVIATION is meaningful only when MEASUREMENT contains a single sample value. In this case, the measurement is considered to be a mean, and STANDARD-DEVIATION represents the statistical standard deviation of the samples used to compute the mean. For arrays, the mean and standard deviation are computed independently for each sample element.

BEGIN-TIME is the time at which acquisition of the measurement in MEASUREMENT began. BEGIN-TIME represents either an absolute date and time (if r=DTIME) or an elapsed time from ORIGIN:CREATION-TIME otherwise.

DURATION is a time interval representing the acquisition duration of the measurement in MEASUREMENT.

REFERENCE is the expected nominal value of a single sample value of the measurement represented in MEASUREMENT.

STANDARD is the measurable quantity of the calibration standard used to produce the MEASUREMENT. For example, a standard used to calibrate a caliper is a steel ring. Its measurable quantity is its inside diameter, say 8 inches. The MEASUREMENT and REFERENCE may represent the same physical quantity as the calibration standard, e.g., length. In this case, STANDARD provides the same information as REFERENCE and is normally absent to avoid redundancy. It is possible, however, for MEASUREMENT and REFERENCE to represent a different physical quantity, say voltage. In this case, STANDARD is needed to describe the transformation from the physical quantity represented by the MEASUREMENT and REFERENCE to the physical quantity of the calibration standard, e.g., from millivolts to inches. Deriving this transformation may require using STANDARD from more than one CALIBRATION-MEASUREMENT object.

PLUS-TOLERANCE indicates by how much each measurement sample value may exceed a reference and still be "within tolerance". Elements shall be non- negative numbers. If a measurement sample value is an array, then so is its reference and plus tolerance. A measurement sample value is within tolerance if each of its elements is less than or equal to the sum of the corresponding reference and plus tolerance elements. Plus tolerance represents in some sense the maximum acceptable drift of each recorded measurement sample above the value of the recorded reference. If PLUS-TOLERANCE is absent, then the plus tolerance is implicitly infinite.

MINUS-TOLERANCE indicates by how much each measurement sample value may fall short of a reference and still be "within tolerance". Elements shall be non-negative numbers. If a measurement sample value is an array, then so is its reference and minus tolerance. A measurement sample value is within tolerance if each of its elements is greater than or equal to the difference of the corresponding reference and minus tolerance elements. Minus tolerance represents in some sense the maximum acceptable drift of each recorded measurement sample below the value of the recorded reference. If MINUS-TOLERANCE is absent, then the minus tolerance is implicitly infinite.

A DLIS-CONTEXT object is used to establish a context for the data related to a particular origin. It is the object referenced from the ORIGIN:CONTEXT attribute for data using the DLIS schema.

Table 4 - DLIS-CONTEXT Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	PRODUCT	c=1, r=ASCII, u=
2	VERSION	c=1, r=ASCII, u=
3	PROGRAMS	r=ASCII, u=
4	ORDER-NUMBER	c=1, r=ASCII, u=
5	DESCENT-NUMBER	-
6	RUN-NUMBER	-
7	WELL-ID	c=1, u=
8	WELL-NAME	c=1, r=ASCII, u=
9	FIELD-NAME	c=1, r=ASCII, u=
10	COMPANY	r=ASCII, u=
11	PRODUCER-CODE	c=1, r=UNORM, u=
12	PRODUCER-NAME	c=1, r=ASCII, u=

*Notes:

PRODUCT is the name of the software product (e.g., the trademarked acquisition or interpretation software system) that produced the data associated with this object.

VERSION is the version of the product specified by PRODUCT.

PROGRAMS is a list of the names of specific programs or services, operating as part of the software specified by PRODUCT, that were used to generate the data associated with this object.

ORDER-NUMBER is a unique accounting number associated with the acquisition or creation of the data associated with this object. It is typically known as the service order number.

DESCENT-NUMBER is meaningful to the producer. The meaning of this attribute is specified by the producer to the consumer by means external to DLIS.

RUN-NUMBER is meaningful to the company or companies specified in COMPANY. The meaning of this attribute is specified to the producer by means external to DLIS.

WELL-ID is a codified identifier of the well in or about which measurements were taken. Whenever applicable, the API Well Number should be used. This is a unique, permanent, numeric identifier assigned to a well in accordance with the American Petroleum Institute Bulletin D12A, January, 1979.

WELL-NAME is the name of the well.

FIELD-NAME is the name of the field to which the well belongs. If there is no field, then the value shall be WILDCAT.

COMPANY is a list of names of the client company or companies for which the data was acquired or computed, typically the operator of the well and partners.

PRODUCER-CODE is the producer's RP66 organization code as found in Appendix A. The producer is the organization whose authorized agent generated the logical file containing this object using software programs developed under the sponsorship of the organization. This code is assigned on request by

PRODUCER-NAME is the producer's business or organization name.

An EQUIPMENT object describes an item of surface or downhole equipment used in the acquisition of data. The purpose of this object type is to record information about individual pieces of equipment of any sort that is used during a job. The TOOL object then collects equipment together in ensembles that are more readily recognizable to the consumer.

Table 5 - EQUIPMENT Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	TRADEMARK-NAME	c=1, r=ASCII, u=
2	STATUS	c=1, r=STATUS, u=
3	TYPE	c=1, r=IDENT | TIDENT, u=, v=(see note)
4	SERIAL-NUMBER	c=1, r=IDENT, u=
5	LOCATION	c=1, r=IDENT | TIDENT, u=, v=(see note)
6	HEIGHT	c=1
7	LENGTH	c=1
8	MINIMUM-DIAMETER	c=1
9	MAXIMUM-DIAMETER	c=1
10	VOLUME	c=1
11	WEIGHT	c=1
12	HOLE-SIZE	c=1
13	PRESSURE	c=1
14	TEMPERATURE	c=1
15	VERTICAL-DEPTH	c=1
16	RADIAL-DRIFT	c=1
17	ANGULAR-DRIFT	c=1

*Notes:

TRADEMARK-NAME is the name used by the producer to refer to the equip- ment.

STATUS indicates the operational status of the equipment.

TYPE is a reference value that indicates the generic type of equipment (see Part 9).

SERIAL-NUMBER is the serial number of the equipment instance.

LOCATION is a reference value that indicates the general location of the equipment (see Part 9).

HEIGHT applies only to equipment located in the borehole. It is the height of the bottom of the equipment above the tool zero point (see 9.7.5) when the tool string containing the equipment is vertical. This value is positive when the equipment bottom is above the tool zero point and is negative when the equipment bottom is below the tool zero point. There is normally one piece of equipment for which the height is zero.

LENGTH is the length of the equipment and is typically measured from bottom make up point to top make up point. It may not apply to surface equipment. The total length of the tool string may not equal the sum of the lengths of all the equipment that make up the tool string, since some equipment may slip over other equipment. Such "slip-on" equipment includes, for example, standoffs, centralizers, and excentralizers. Similarly, the height of a piece of equipment may be independent of the lengths of the equipment below it.

MINIMUM-DIAMETER applies to equipment used in the borehole. It is the minimum outer diameter of the equipment. This is defined to be the minimum horizontal cross-sectional diameter measured when the equipment is in a vertical configuration. For extendible or compressible equipment (e.g., caliper arms and centralizers), this measurement indicates the smallest operational diameter possible.

MAXIMUM-DIAMETER applies to equipment used in the borehole. It is the maximum outer diameter of the equipment. This is defined to be the maximum horizontal cross-sectional diameter measured when the equipment is in a vertical configuration. For extendible or compressible equipment (e.g., caliper arms and centralizers), this measurement indicates the largest operational diameter possible.

VOLUME is the volume of the equipment and is typically used to determine bouyant weight of the equipment. It may not apply to surface equipment.

WEIGHT is the weight of the equipment in air. It may not apply to surface equipment.

HOLE-SIZE applies to equipment in the borehole. It is the minimum borehole diameter for which the equipment may reasonably be used.

PRESSURE is the maximum operational pressure rating of the equipment, when applicable.

TEMPERATURE is the maximum operational temperature rating of the equipment, when applicable.

VERTICAL-DEPTH is the vertical depth of an equipment item that is normally stationary (see 2.36).

RADIAL-DRIFT is the radial drift of an equipment item that is normally stationary (see 2.28).

ANGULAR-DRIFT is the angular drift of an equipment item that is normally stationary (see 2.2).

A MESSAGE object is used to write a textual message tied to other data by means of a time stamp and other indexing attributes. Such messages typically represent operator interaction with the system, e.g., a "scroll" of the logging session, or informational messages concerning events that occurred during the session.

Table 6 - MESSAGE Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	TYPE	c=1, r=IDENT | TIDENT, u=, v=(see note)
2	TIME	c=1
3	MEASURED-DEPTH	c=1
4	VERTICAL-DEPTH	c=1
5	RADIAL-DRIFT	c=1
6	ANGULAR-DRIFT	c=1
7	TEXT	r=ASCII, u=

*Notes:

TYPE is a reference value indicating the source and purpose of the message (see Part 9). This attribute is required.

TIME is the time the message was issued.

MEASURED-DEPTH is the measured depth of the tool zero point at the time the message was issued (see 2.20)

VERTICAL-DEPTH is the vertical depth of the tool zero point at the time the message was issued (see 2.36)

RADIAL-DRIFT is the radial drift of the tool zero point at the time the message was issued (see 2.28)

ANGULAR-DRIFT is the angular drift of the tool zero point at the time the message was issued (see 2.2)

TEXT is the text of the message. This attribute is required.

A PATH object is used to identify channels that represent the coordinates of a path along which a logging tool string may pass and to specify certain geometric features of the tool string relative to the path.

Log data consists of a sequence of values (i.e., a channel) traversing a locus in space and time. A locus in space and time is a sequence of distinct points, each of which, in the most general case, has a three-dimensional position coordinate, and a time coordinate. The sequence {valuei, positioni, timei} is called a data path, and each member of the sequence is called a step on the data path. The sequence {positioni, timei} is the locus of the data path. Note that it is possible for two points on a locus to occupy the same position in space so long as they occupy that position at different times. In the extreme case, a locus can have a fixed position.

A complete position coordinate is made up of three components that correspond to the spatial coordinate system of a well (see Figure 1): depth (measured or vertical), radial drift, and angular drift. Occasionally, both measured and vertical depth components are known and are recorded together.

Data paths are represented as subgroups of channels in frames. Some or all of the components of a data path may be recorded; other components may be unknown or irrelevant. The {valuei} sequence, known as the data path's value channel, is always recorded. The mechanism for defining data paths is the PATH object. PATH objects are not needed to decode frames, but they add informational value to the contents of frames.

A tool string has three points of particular interest. They are its measure point, its tool zero point, and its data reference point (see Figure 3). These points give rise to a depth offset and a measure point offset which are critical for interpreting the relation between an index channels and data channels in a frame type.

A channel is sampled at its measure point, which is a fixed position relative to the tool string, whenever a data reference point (another fixed position relative to the tool string) passes certain positions along the well. If the well positions are equally spaced in depth, and if the interval between the measure point and the data reference point is not evenly divisible by the sampling interval, the channel will have a depth offset. Figure 3 - Tool String Configuration

Table 7 - PATH Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	FRAME-TYPE	c=1, r=OBNAME, u=
2	WELLBORE-PATH-DATUM	c=1, r=OBNAME, u=
3	VALUE	r=OBNAME, u=
4	MEASURED-DEPTH	c=1
5	VERTICAL-DEPTH	c=1
6	RADIAL-DRIFT	c=1
7	ANGULAR-DRIFT	c=1
8	TIME	c=1
9	DEPTH-OFFSET	c=1
10	MEASURE-POINT-OFFSET	c=1
11	TOOL-ZERO-OFFSET	c=1

*Notes:

FRAME-TYPE is the name of a FRAME object that describes the frame type in which the path channels are recorded.

WELLBORE-PATH-DATUM is the name of a WELLBORE-PATH-DATUM object that describes the wellbore path datum for this path.

VALUE is a list of names of CHANNEL objects that describe one or more value channels for this path. This attribute is required.

MEASURED-DEPTH is a constant measured depth coordinate for this path if r is numeric, or the name of a CHANNEL object if r=OBNAME that describes a measured depth channel for this path.

VERTICAL-DEPTH is a constant vertical depth coordinate for this path if r is numeric, or the name of a CHANNEL object if r=OBNAME that describes a vertical depth channel for this path.

RADIAL-DRIFT is a constant radial drift coordinate for this path if r is numeric, or the name of a CHANNEL object if r=OBNAME that describes a radial drift channel for this path.

ANGULAR-DRIFT is a constant angular drift coordinate for this path if r is numeric, or the name of a CHANNEL object if r=OBNAME that describes a angular drift channel for this path.

TIME is a constant time coordinate for this path if r is numeric, or the name of a CHANNEL object if r=OBNAME that describes a time channel for this path. If r is numeric and not DTIME, it represents elapsed time since ORIGIN:CREATION-TIME.

DEPTH-OFFSET is a depth offset, which indicates how much VALUE is "off depth". This is meaningful only when there is a measured depth channel for this path. If D is the value of the measured depth channel in a frame and D' is the actual known measured depth at which channels in the frame were sampled, then D = D' + depth offset.

MEASURE-POINT-OFFSET is a measure point offset, which indicates a fixed distance along measured depth from the value channel's measure point to a data reference point. This is a special case that depends on the data acquisition model and applies only when there is a recorded measured depth channel for this Path. If MEASURE-POINT-OFFSET is zero or absent, then the time channel for this path is explicitly related to the value channel. That is, in each frame, vi is sampled at ti. If the MEASURE-POINT-OFFSET is present and non-zero, then the time channel is instead explicitly related to the data reference point, and is implicitly related to the value channel. In each frame, ti is the time that the data reference point was at di, which is the frame's measured depth. The value channel sample vi is still considered to be sampled at di, but at a time different from ti. The explicit time for the value channel can be recovered using the knowledge that at time ti when the data reference point was at depth di, the value channel measure point was at depth di - measure point offset. Typically, only a single time channel per origin will be recorded in a frame type, the one explicitly associated with the data reference point.

TOOL-ZERO-OFFSET is the distance of the data reference point for this path above the tool string's tool zero point. It may be positive or negative and is frequently zero. Specifically, data reference point = tool zero point + tool zero offset.

A SPLICE object is used to identify the component channels of a splice and the splice points. A splice is the result of taking values of two or more distinct channels (e.g., from different runs) from mutually disjoint intervals to produce a resultant channel defined over the union of the intervals.

Table 8 - SPLICE Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	OUTPUT-CHANNEL	c=1, r=OBNAME, u=
2	INPUT-CHANNELS	r=OBNAME, u=
3	ZONES	r=OBNAME, u=

*Notes:

OUTPUT-CHANNEL is the name of a CHANNEL object that represents the spliced channel, i.e., the resultant of the splice operation. The spliced channel may be implied by the SPLICE object and need not actually exist. When the spliced channel does exist, its PROPERTIES Attribute shall include the reference value SPLICED.

INPUT-CHANNELS is a list of names of CHANNEL objects that represent the input channels of the splice operation. This attribute is required.

ZONES is a list of names of ZONE objects that describe mutually disjoint intervals in which the spliced channel is defined. When present, ZONES count matches INPUT-CHANNELS count. The spliced channel is derived from the kth input channel in the kth zone. If ZONES is absent, then INPUT-CHANNELS count shall be 1, and API basic schema UPDATE objects are used to indicate where input channels change.

A TOOL object is used to record information about a logging tool and its component equipment parts.

TOOL objects specify ensembles of equipment that work together to provide specific measurements or services. Such combinations are more recognizable to the consumer than are their individual pieces. A typical tool consists of a sonde and a cartridge and possibly some appendages such as centralizers and spacers. It is also possible to identify certain pieces or combinations of surface measuring equipment as tools.

Table 9 - TOOL Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	TRADEMARK-NAME	c=1, r=ASCII, u=
2	GENERIC-NAME	c=1, r=ASCII, u=
3	PARTS	r=OBNAME, u=
4	STATUS	c=1, r=STATUS, u=
5	CHANNELS	r=OBNAME, u=
6	PARAMETERS	r=OBNAME, u=

*Notes:

TRADEMARK-NAME is the name used by the producer to refer to the tool.

GENERIC-NAME is the name generally used within the industry to refer to tools of this type.

PARTS is a list of names of EQUIPMENT objects that represent the parts of the tool.

STATUS indicates whether the tool is enabled to provide information to the acquisition system or whether it has been disabled and is simply occupying space.

CHANNELS is a list of names of CHANNEL objects describing channels that are produced directly by this tool. A channel shall not be produced directly by more than one tool. Channels that have multiple tool sources should be associated with their indirect tool sources via API basic schema PROCESS objects.

PARAMETERS is a list of names of PARAMETER objects describing parameters that directly affect or reflect the operation of this tool. Parameters may be shared by different tools.

A WELLBORE-PATH-DATUM object used to record the location of a wellbore path datum. This object type was called WELL-REFERENCE-POINT in RP66 V1. The name change was made to correspond to standard terminology found in the Petroleum Industry Data Dictionary (PIDD).

Table 10 - WELLBORE-PATH-DATUM Attributes
*Note	Attribute Label	Restrictions
-	DESCRIPTION	c=1, r=ASCII, u=
-	EXTENDED-ATTRIBUTES	r=OBJREF, u=
1	PERMANENT-DATUM	c=1, r=ASCII, u=
2	VERTICAL-ZERO	c=1, r=ASCII, u=
3	PERMANENT-DATUM-ELEVATION	c=1
4	ABOVE-PERMANENT-DATUM	c=1
5	MAGNETIC-DECLINATION	c=1
6	COORDINATE-1-NAME	c=1, r=ASCII, u=
7	COORDINATE-1-VALUE	c=1
8	COORDINATE-2-NAME	c=1, r=ASCII, u=
9	COORDINATE-2-VALUE	c=1
10	COORDINATE-3-NAME	c=1, r=ASCII, u=
11	COORDINATE-3-VALUE	c=1

*Notes:

PERMANENT-DATUM is a permanent entity or structure (e.g., ground level) from which vertical distance can be measured.

VERTICAL-ZERO is a particular entity (e.g., kelly bushing) that corresponds to zero measured depth.

PERMANENT-DATUM-ELEVATION is the distance of the PERMANENT- DATUM above mean sea level. A negative value indicates the distance is below mean sea level.

ABOVE-PERMANENT-DATUM is the distance of VERTICAL-ZERO above PERMANENT-DATUM. If negative, then VERTICAL-ZERO is below PERMANENT-DATUM.

MAGNETIC-DECLINATION is the angle with vertex at the wellbore path datum determined by the line of direction to geographic north and the line of direction to magnetic north. A positive value indicates that magnetic north is east of geographic north. A negative value indicates that magnetic north is west of geographic north.

COORDINATE-1-NAME is the name of the first of three independent spatial coordinates, such as longitude or latitude or elevation, that can be used to locate the wellbore path datum.

COORDINATE-1-VALUE is the numerical value of the coordinate named by COORDINATE-1-NAME.

COORDINATE-2-NAME is the name of the second of three independent spatial coordinates, such as longitude or latitude or elevation, that can be used to locate the wellbore path datum.

COORDINATE-2-VALUE is the numerical value of the coordinate named by COORDINATE-2-NAME.

COORDINATE-3-NAME is the name of the third of three independent spatial coordinates, such as longitude or latitude or elevation, that can be used to locate the wellbore path datum.

COORDINATE-3-VALUE is the numerical value of the coordinate named by COORDINATE-3-NAME.

Table 11 lists attributes of the DLIS schema that may be updated using UPDATE objects.

Table 11 - Updatable Attributes
*Note	Object Type	Attribute Label
1	CALIBRATION-COEFFICIENT	COEFFICIENTS
2	SPLICE	INPUT-CHANNELS

*Notes:

Update of COEFFICIENTS indicates an adjustment or correction of some kind. The updated values may not be directly derived from measurements.

When a splice operation begins, it may not be known what all of the input channels will be. It must be possible to provide this information on the fly. The INPUT-CHANNELS attribute may be updated if and only if the ZONES attribute is absent. In this case, the count of INPUT-CHANNELS is 1, and an update indicates a change in the input channel at the frames indicated by the UPDATE object. A simple application of calibration is the linear two-point method. Two measurements are taken and compared against two references. The comparison yields a gain coefficient and an offset coefficient, which are then used to compute calibrated values from uncalibrated measurements.