Download PPT - Energistics

A Practical Lithology Reference
Standard
Paul Maton (POSC)
and
Gary Masters (POSC)
Outline
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Introduction
Business Objectives, Motivation and Work flows
Resources
Lithology in WITSML 1.3
Enhanced Lithological Classification
Conclusions
Objectives and Requirements
• Provide evolving dictionary in XML of lithological
terminology for use in:
– end-2004 WITSML Version 1.3 Mudlog and Core
specifications
– revised lithological classification, 2Q05
– next WITSML Mudlog version 1.3.1, late 2005?
• Improve or simplify existing specification(s)
• Lithological terminology needed for POSC
exchange standards
• Easy maintenance and extensibility
Business Drivers
• Operator Point of View
– Standard vocabulary and semantics for lithologies will
improve the following processes
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Assimilating results of outsourced work
Information exchanges with partners, regulators
Reduction of ambiguity and uncertainty in data
Common nomenclature used for mudlog, core and other rock
sample descriptions
• Service Company Point of View
– Enable use of same nomenclature and classifications in
services and software for many customers
• Cost savings in software engineering and maintenance
• Cost savings and consistency in information produced
Use Cases
• Mudlog
– Rapid wellsite description of rock cuttings
• Core analysis
– Full description of petrographic and quantitative
properties (porosity, permeability, density, etc.)
• Detailed Rock description and analysis
– Optical and electron microscopy analysis
Available Resources
• Landmark Graphics
– List of Lithology Classes with Qualifiers and Symbol
Codes
• Norwegian Petroleum Directorate
– Reporting requirements for Digital Well Data:
Lithological Codes
• Shell
– 1995 Standard Legend
• Statoil
– Current Listing of Lithological codes
• Geological Literature
Common Descriptors for
WITSML Mud-Log
• Primary and secondary lithologies
• Use of the following characteristics as Qualifiers
•Mineral content
•Fossil content
•Cement
•Grain size
•Sorting
•…~ 10 others
Lithology types in WITSML v1.3
used by Mudlog and Core - 1
Andesite
Coal
Granite
Anhydrite
Conglomerate
Gravel
Arkose
Diabase
Greenstones
Basalt
Diorite
Greywacke
Breccia
Dolerite
Gumbo
Calcarenite
Dolomite
Gypsum
Calcilutite
Dolomite, Calcareous
Halite
Calcisiltite
Extrusive Rock
(Volcanic)
Igneous
Chalk
Chert
Clay
Claystone
Feldspar
Gabbro
Glauconite
Gneiss
Intrusvie Rock (Plutonic)
Lignite
Limestone
Limestone, Argillaceous
Qualifiers in WITSML v1.3
used by Mudlog and Core - 1
Anhydrite
Chalky
Dolomitic
Argillaceous
Chamosite
Feldspar
Barite
Chert
Ferruginous
Belemnitic
Chlorite
Fissile
Bioturbated
Concretions
Forams gen
Bituminous
Conglomeratic
Fossil Frags
Bryozoans
Coral
Fossils gen
Burrowed
Crinoids
Glauconite
Calcareous
Diatoms
Glauconitic
Calcite concr
Dolomite concr
Gravelly
Calcitic
Dolomite Stringer
Gypsiferous
Carbonaceous
Halite
Outline
•
•
•
•
•
•
Introduction
Business Objectives, Motivation and Work flows
Resources
Lithology in WITSML 1.3
Enhanced Lithological Classification
Conclusions
Enhanced Lithological Classification
• Current approaches
– Base on Shell ’95 standard legend
– Add sedimentary rock types with names, descriptions,
abbreviations and adjectives
– Add mineral types, names, abbreviations and adjectives
– Possibly provide images of rocks as go-bys
– Avoid over-complication
• Produce draft classification and taxonomy from
available resources
• Validation by practising geologists
Material Classification
Material
Property
Mineral
Sedimentary
Rock
Composition
Fossil
Igneous
Fluid
Metamorphic
Property and Composition are attribute sets inherited by Minerals and Rocks etc,
but the sets have additional attributes in, and appropriate to, each sub-class
Common attributes of Sedimentary
Rocks - 1
• Textural & Compositional
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Grain size
Sorting
Roundness
Sphericity
Compaction
Non-skeletal particles
(lithic fragments)
– Pellets and grains
• Porosity & Permeability
– Qualitative and
quantitative
– Fabric and non-fabric
selective
– Archie classification and
types
• Color
– Names, abbreviations &
qualifiers
Examples
• Sorting
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unsorted
[((srt))]
very poorly sorted [((srt))]
poorly sorted
[(srt)]
poorly to moderately well sorted
[(srt)-srt]
moderately well sorted [srt]
well sorted
[srt]
very well sorted
[srt]
unimodally sorted
[unimod srt]
bimodally sorted
[bimod srt]
• Compaction
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not compacted [not cmp]
slightly compacted [(cmp)]
compacted
[ cmp ]
strongly compacted cmp
friable
[ fri ]
indurated
[ ind ]
hard
[ hd ]
• Color
– green [ gn ], dark [ dk ]
[Note: Entire abbreviations, including parentheses, are in Square Brackets]
Common attributes of Sedimentary
Rocks - 2
• Accessory Minerals
– References extensible list and abbreviations of mineral
class names
– e.g.: Feldspar (Fld)
• Fossil content
– References extensible list and abbreviations of fossil
class names
– e.g.: Bryozoa (Bry)
Common attributes of Sedimentary
Rocks - 3
• Stratification and Sedimentary Features
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Bedding thickness and appearance
Character of base of bed
Large non-bedded features: lens, bioherm etc
Cross bedding and lamination
Ripplemarks
Planar laminations
Graded bedding
Soft sediment deformation
Syn-depositional features
Common attributes of Sedimentary
Rocks - 4
• Post-depositional features
– Consolidation, cementation, weathering
– Diagenetic structures
– Nodules and concretions
Igneous and Metamorphic Rocks
• Minimal treatment given that these are not often
of primary interest in E&P
• Names, descriptions, abbreviations and adjectival
forms of ~12 types in each category
– Examples
– Granite, (Gr), granitic
– Schist, (Sch or sch???), schistose
Next steps
• Collect feedback from April informal SIGs
– Requirements, use cases, and availability of specialists
• Review meetings with SIG member specialists in
May
• Revise and publish Standard by end June
• Promote and assist pilot implementations in
2H2005
Conclusions
• XML based Lithologic vocabulary is under
development and will be partially implemented for
Mud logging part of WITSML 1.3
• Design is for usage in wider rock description and
analysis, including wellsite and laboratory work
• Draft specification will be posted in 2Q2005,
reviewed by SIG Member geological experts, then
revised and published by POSC
Thank you for your attention
More information from
Paul Maton
Alan Doniger
Gary Masters
maton@posc.org
doniger@posc.org
masters@posc.org
+44 1932 828794
+1 713 267 5124
+1 713 267 5111