LAS FORMAT VERSION 2.0 INFORMATION PACKAGE AUGUST 28, 1995 ________________________ Enclosed are the following items: 1) A technical paper on the LAS format.(run CERTIFY to get copy) 2) An information sheet on the REFORMAT program (in README.TXT) 3) An information sheet on the CERTIFY program (in README.TXT) 4) Information on NEW FEATURES OF LAS VERSION 2.0 (in README.TXT) 5) a 3.5 inch, 1.44 megabyte floppy disk (MS/DOS, PC/DOS compatible) containing the following files: - README.TXT = introduction to LAS information package - REFORMAT.EXE = executable of the REFORMAT program - CERTIFY.EXE = executable of the CERTIFY program - TEST01.LAS = example file of LAS format in unwrapped mode - TEST02.LAS = example file of LAS format in wrapped mode - TEST03.LAS = another example of an LAS file - MAIN.C = code for REFORMAT program (ANSI standard 'C') - DEPTH.C = as above - CURVE.C = as above - REVERSE.C = as above - RESAMP.C = as above - UNWRAP.C = as above - SCAN.C = as above - CONVERT.C = as above - CONVER_A.C = as above - REFORMAT.MAK = as above - LOCAL.H = as above _________________________________________________________________________ ________________________________________________________________________ CERTIFY (VERSION 3.50) MARCH 23, 1994 ____________________ The CERTIFY program was designed to read LAS version 2.0 files and establish whether all of the LAS specifications are being adhered to. This program also points out where the LAS specifications are not being followed This program issues two types of messages. One is a WARNING and the other is a FATAL ERROR. The WARNING is used to point out items that meet the LAS standard but could be improved upon to make the file more informative to the user. For example, if the "location" field in the Well Information Section is left blank the CERTIFY program will issue a WARNING. The FATAL ERROR message is issued on items that fail to meet the LAS specifications. For example if the "location" field is omitted from the Well Information Section, the CERTIFY program will issue a FATAL ERROR message. The CERTIFY program is not part of the LAS Standard. It is being made available to assist the user in locating and identifying the more commonly occurring errors. _____________________________________________________________________________ _____________________________________________________________________________ REFORMAT (VERSION 2.51) AUGUST 28, 1995 _________________________________ The REFORMAT program was designed to manipulate LAS formatted files into a form which may be more compatible with the user's needs. The REFORMAT program is not part of the LAS standard. The REFORMAT program is capable of doing the following things: 1) Extract a depth interval - This allows the user to build a new LAS file covering a specific depth interval of the input interval. It works on unwrapped data only. It will handle lines up to 1200 characters long. 2) Extract one or more curves - This allows the user to build a new LAS file containing only the curves specified by him. It will handle input data with lines up to 1200 characters long. It works only on unwrapped data. 3) Reverse depth direction - Logs can be recorded from bottom to top or visa versa. This routine reverses the depth direction. It works on unwrapped data only. It will handle lines up to 1200 characters long. 4) Change depth step (i.e. depth increment) - The depth step refers to the depth increment. This routine works only on unwrapped data. It will handle lines up to 600 characters long, input files with up to 20,000 data lines and output files with up to 100,000 data lines. 5) Convert wrap to unwrap mode - Wrap mode refers to the mode where the depth value is on its own line and all of the curve data for that depth value are on the lines that follow (see TEST02.LAS for an example). Unwrap mode means there is only one line of curve data for each depth step and the depth value is the first value in that line. This routine converts wrapped data to the unwrapped mode provided that the resulting lines are not longer than 1200 characters 6) Scan for non-standard characters - Non ASCII or unprintable characters can cause difficulties to some programs. This routine allows the user to find them and delete them. 7) Convert LAS version 1.2 to LAS version 2.0 8) Convert LAS version 2.0 to LAS version 1.2 The REFORMAT program was written in ANSI standard 'C' and has been compiled with Boreland's Turbo C++ 3.0 compiler. The author of the program does not reserve any rights and does not warrant the program for any specific purpose. The executable as well as the code for REFORMAT is included on the enclosed floppy disk. Any comments should be addressed to: CWLS Floppy Disk Committee Suite 229, 640-5 Avenue S.W. Calgary, Alberta CANADA T2P 0M6 LAS FORMAT INFORMATION PACKAGE AUGUST 28, 1995 _____________________________________________________________________________ _____________________________________________________________________________ SEPTEMBER 25, 1992 NEW FEATURES OF LAS VERSION 2.0 THE FLOPPY DISK STANDARD FOR LOG DATA BY Canadian Well Logging Society's LAS Committee Case Struyk Gulf Canada Resources Ltd. (Chairman) Ray Lamborn Atlas Wireline Services Glenn Gray BPB Wireline Services Jos Jonkers Computalog Ltd. Gregg Peterson Great Guns Logging Services George Tulle Halliburton Logging Services Gary Drebit Schlumberger of Canada INTRODUCTION The original LAS standard was introduced by the Canadian Well Logging Society in 1989. Its intent was to standardize the organization of digital log curve information for floppy disks. It did this very successfully and the standard is now popular worldwide. This new version corrects one of the shortcomings of the earlier version and has improved documentation. LAS version 2.0 replaces version 1.2 . Highlights of the changes are as follows: - The "WELL INFORMATION" section has been standardized to conform with the "CURVE INFORMATION " and the "PARAMETER INFORMATION" sections. - The documentation in regards to the locating of the "UNITS" in various sections has been clarified to indicate that they must be located directly to the right of the dot without any spaces. - An additional example has been added to the documentation to illustrate a method of handling time based data The CERTIFY and REFORMAT programs have been modified to handle LAS version 2.0 . The REFORMAT program contains an option that will convert LAS version 1.2 to version 2.0 . CHANGES TO THE WELL INFORMATION SECTION The "WELL INFORMATION" section has been made to conform with the "CURVE INFORMATION" and "PARAMETER INFORMATION" sections. All of these sections will now consist of lines laid out as follows: MNEM.UNITS DATA :DESCRIPTION OF MNEMONIC Where MNEM = mnemonic. This mnemonic can be of any length but must not contain any internal spaces dots or colons. Spaces are permitted in front of the mnemonic and between the end of the mnemonic and the dot. UNITS = units of the mnemonic (if applicable). The units must be located directly after the dot. There must be no spaces between the units and the dot. The units can be of any length but must not contain any colons or internal spaces. DATA = value of, or data relating to, the mnemonic. This value or input can be of any length and can contain spaces or dots as appropriate, but must not contain any colons. It must be preceded by at least one space to demarcate it from the units and must be to the left of the colon. DESCRIPTION = description or definition of the mnemonic. It is always located to the right of the colon. Its length is limited by the total line length limit of 256 characters which must include a carriage return and a line feed. The changes in LAS version 2.0 effect the following lines in the WELL INFORMATION section: - The COMP line will now have the actual company name to the left of the colon, and the word "company" to the right of the colon. - The WELL line will have the actual well name to the left of the colon and the word "well" to the right of the colon. - the PROV, CNTY, STAT, CTRY lines will have the actual province, county, state, or country name to the right of the colon, and the word "province", "county", "state", or "country" to the right of the colon. - The SRVC line will have the actual service company name to the left of the colon, and the words "service company" to the right of the colon. - The DATE line will have the actual date to the left of the colon and the word "date" to the right of the colon. - The UWI or API line will have the actual UWI or actual API location to the left of the colon and the words "unique well identifier" or "API location code" to the right of the colon The following is an example of a Well Information Section in LAS version 2.0: ~Well Information Section #MNEM.UNIT DATA DESCRIPTION OF MNEMONIC #--------- ----------- --------------------------- STRT.M 635.0000 :START DEPTH STOP.M 400.0000 :STOP DEPTH STEP.M -0.1250 :STEP NULL. -999.25 :NULL VALUE COMP. ANY OIL COMPANY INC. :COMPANY WELL. ANY ET AL 12-34-12-34 :WELL FLD . WILDCAT :FIELD LOC . 12-34-12-34W5 :LOCATION PROV. ALBERTA :PROVINCE SRVC. ANY LOGGING COMPANY INC. :SERVICE COMPANY DATE. 13-DEC-86 :LOG DATE UWI . 100123401234W500 :UNIQUE WELL ID CLARIFICATION OF THE LOCATION OF UNITS The original documentation was not specific enough as to the exact location of the units in the WELL, CURVE, and PARAMETER sections. The units must be located directly after the first dot on a line. There must be no spaces between the dot and the units. CONCLUSIONS A new LAS information package has been released and includes REFORMAT and CERTIFY programs modified for LAS version 2.0 . The REFORMAT program will be capable of converting LAS version 1.2 to version 2.0 . This information package is available for $10.00 at the following address: Canadian Well Logging Society 229, 640 - 5 Avenue SW Calgary, Alberta T2P 0M6 CANADA The LAS Committee will continue to monitor the LAS standard. Feedback concerning this standard is greatly appreciated and should be forwarded to the committee at the above address. APPENDIX - EXAMPLE LAS FILES EXAMPLE #1 - THE LAS STANDARD IN UNWRAPPED MODE ~VERSION INFORMATION VERS. 2.0 : CWLS LOG ASCII STANDARD -VERSION 2.0 WRAP. NO : ONE LINE PER DEPTH STEP ~WELL INFORMATION #MNEM.UNIT DATA DESCRIPTION OF MNEMONIC #----- ----- ---------- -------------------------- STRT .M 1670.0000 :START DEPTH STOP .M 1669.7500 :STOP DEPTH STEP .M -0.1250 :STEP NULL . -999.25 :NULL VALUE COMP . ANY OIL COMPANY INC. :COMPANY WELL . ANY ET AL 12-34-12-34 :WELL FLD . WILDCAT :FIELD LOC . 12-34-12-34W5 :LOCATION PROV . ALBERTA :PROVINCE SRVC . ANY LOGGING COMPANY INC. :SERVICE COMPANY DATE . 13-DEC-86 :LOG DATE UWI . 100123401234W500 :UNIQUE WELL ID ~CURVE INFORMATION #MNEM.UNIT API CODES CURVE DESCRIPTION #----------- --------- ------------------------- DEPT .M : 1 DEPTH DT .US/M 60 520 32 00 : 2 SONIC TRANSIT TIME RHOB .K/M3 45 350 01 00 : 3 BULK DENSITY NPHI .V/V 42 890 00 00 : 4 NEUTRON POROSITY SFLU .OHMM 07 220 04 00 : 5 RXORESISTIVITY SFLA .OHMM 07 222 01 00 : 6 SHALLOW RESISTIVITY ILM .OHMM 07 120 44 00 : 7 MEDIUM RESISTIVITY ILD .OHMM 07 120 46 00 : 8 DEEP RESISTIVITY ~PARAMETER INFORMATION #MNEM.UNIT VALUE DESCRIPTION #--------- --------- ---------------------- MUD . GEL CHEM : MUD TYPE BHT .DEGC 35.5000 : BOTTOM HOLE TEMPERATURE BS .MM 200.0000 : BIT SIZE FD .K/M3 1000.0000 : FLUID DENSITY MATR . SAND : NEUTRON MATRIX MDEN . 2710.0000 : LOGGING MATRIX DENSITY RMF .OHMM 0.2160 : MUD FILTRATE RESISTIVITY DFD .K/M3 1525.0000 : DRILL FLUID DENSITY ~OTHER Note: The logging tools became stuck at 625 metres causing the data between 625 metres and 615 metres to be invalid. ~A DEPTH DT RHOB NPHI SFLU SFLA ILM ILD 1670.000 123.450 2550.000 0.450 123.450 123.450 110.200 105.600 1669.875 123.450 2550.000 0.450 123.450 123.450 110.200 105.600 1669.750 123.450 2550.000 0.450 123.450 123.450 110.200 105.600 EXAMPLE #2 - ILLUSTRATING THE LAS STANDARD WITH MINIMUM HEADER REQUIREMENTS IN UNWRAPPED MODE. ~V VERS . 2.0 : CWLS log ASCII Standard -VERSION 2.0 WRAP. NO : One line per depth step ~W STRT.M 635.0000 :START DEPTH STOP.M 634.5000 :STOP DEPTH STEP.M -0.1250 :STEP NULL. -999.25 :NULL VALUE COMP. ANY OIL COMPANY INC. :COMPANY WELL. ANY ET AL 12-34-12-34 :WELL FLD . WILDCAT :FIELD LOC . 12-34-12-34W5 :LOCATION PROV. ALBERTA :PROVINCE SRVC. ANY LOGGING COMPANY INC. :SERVICE COMPANY DATE . 13-DEC-86 :LOG DATE UWI . 100123401234W500 :UNIQUE WELL ID ~C DEPT .M : DEPTH RHOB .K/M3 : BULK DENSITY NPHI .VOL/VOL : NEUTRON POROSITY -SANDSTONE MSFL .OHMM : Rxo RESISTIVITY SFLA .OHMM : SHALLOW RESISTIVITY ILM .OHMM : MEDIUM RESISTIVITY ILD .OHMM : DEEP RESISTIVITY SP .MV : SPONTANEOUS POTENTIAL ~A 635.0000 2256.0000 0.4033 22.0781 22.0781 20.3438 3.6660 123.4 634.8750 2256.0000 0.4033 22.0781 22.0781 20.3438 3.6660 123.4 634.7500 2256.0000 0.4033 22.0781 22.0781 20.3438 3.6660 123.4 634.6250 2256.0000 0.4033 22.0781 22.0781 20.3438 3.6660 123.4 634.5000 2256.0000 0.4033 22.0781 22.0781 20.3438 3.6660 123.4 EXAMPLE #3 - ILLUSTRATING THE WRAPPED VERSION OF THE LAS STANDARD ~VERSION INFORMATION VERS . 2.0 : CWLS log ASCII Standard -VERSION 2.0 WRAP. YES : Multiple lines per depth step ~WELL INFORMATION #MNEM.UNIT DATA DESCRIPTION OF MNEMONIC #----- ----- ------- --------------------------- STRT .M 910.0000 :START DEPTH STOP .M 909.5000 :STOP DEPTH STEP .M -0.1250 :STEP NULL . -999.25 :NULL VALUE COMP . ANY OIL COMPANY INC. :COMPANY WELL . ANY ET AL 12-34-12-34 :WELL FLD . WILDCAT :FIELD LOC . 12-34-12-34W5 :LOCATION PROV . ALBERTA :PROVINCE SRVC . ANY LOGGING COMPANY INC. :SERVICE COMPANY SON . 142085 :SERVICE ORDER NUMBER DATE . 13-DEC-86 :LOG DATE UWI . 100123401234W500 :UNIQUE WELL ID ~CURVE INFORMATION #MNEM.UNIT CURVE DESCRIPTION #--------- -------------------- DEPT .M : Depth DT .US/M : 1 Sonic Travel Time RHOB .K/M : 2 Density-Bulk Density NPHI .V/V : 3 Porosity -Neutron RX0 .OHMM : 4 Resistivity -Rxo RESS .OHMM : 5 Resistivity -Shallow RESM .OHMM : 6 Resistivity -Medium RESD .OHMM : 7 Resistivity -Deep SP .MV : 8 Spon.Potential GR .GAPI : 9 Gamma Ray CALI .MM : 10 Caliper DRHO .K/M3 : 11 Delta-Rho EATT .DBM : 12 EPT Attenuation TPL .NS/M : 13 TP -EPT PEF . : 14 Photoelectric Factor FFI .V/V : 15 Porosity -NML FFI DCAL .MM : 16 Caliper-Differential RHGF .K/M3 : 17 Density-Formation RHGA .K/M3 : 18 Density-Apparent SPBL .MV : 19 Baselined SP GRC .GAPI : 20 Gamma Ray BHC PHIA .V/V : 21 Porosity -Apparent PHID .V/V : 22 Porosity -Density PHIE .V/V : 23 Porosity -Effective PHIN .V/V : 24 Porosity -Neut BHC PHIC .V/V : 25 Porosity -Total HCC R0 .OHMM : 26 Ro RWA .OHMM : 27 Rfa SW . : 28 Sw -Effective MSI . : 29 Sh Idx -Min BVW . : 30 BVW FGAS . : 31 Flag -Gas Index PIDX . : 32 Prod Idx FBH . : 33 Flag -Bad Hole FHCC . : 34 Flag -HC Correction LSWB . : 35 Flag -Limit SWB ~A Log data section 910.000000 -999.2500 2692.7075 0.3140 19.4086 19.4086 13.1709 12.2681 -1.5011 96.5306 204.7177 30.5822 -999.2500 -999.2500 3.2515 -999.2500 4.7177 3025.0264 3025.0264 -1.5010 93.1378 0.1641 0.0101 0.1641 0.3140 0.1641 11.1397 0.3304 0.9529 0.0000 0.1564 0.0000 11.1397 0.0000 0.0000 0.0000 909.875000 -999.2500 2712.6460 0.2886 23.3987 23.3987 13.6129 12.4744 -1.4720 90.2803 203.1093 18.7566 -999.2500 -999.2500 3.7058 -999.2500 3.1093 3004.6050 3004.6050 -1.4720 86.9078 0.1456 -0.0015 0.1456 0.2886 0.1456 14.1428 0.2646 1.0000 0.0000 0.1456 0.0000 14.1428 0.0000 0.0000 0.0000 909.750000 -999.2500 2692.8137 0.2730 22.5909 22.5909 13.6821 12.6146 -1.4804 89.8492 201.9287 3.1551 -999.2500 -999.2500 4.3124 -999.2500 1.9287 2976.4451 2976.4451 -1.4804 86.3465 0.1435 0.0101 0.1435 0.2730 0.1435 14.5674 0.2598 1.0000 0.0000 0.1435 0.0000 14.5674 0.0000 0.0000 0.0000 909.625000 -999.2500 2644.3650 0.2765 18.4831 18.4831 13.4159 12.6900 -1.5010 93.3999 201.5826 -6.5861 -999.2500 -999.2500 4.3822 -999.2500 1.5826 2955.3528 2955.3528 -1.5010 89.7142 0.1590 0.0384 0.1590 0.2765 0.1590 11.8600 0.3210 0.9667 0.0000 0.1538 0.0000 11.8600 0.0000 0.0000 0.0000 909.500000 -999.2500 2586.2822 0.2996 13.9187 13.9187 12.9195 12.7016 -1.4916 98.1214 201.7126 -4.5574 -999.2500 -999.2500 3.5967 -999.2500 1.7126 2953.5940 2953.5940 -1.4916 94.2670 0.1880 0.0723 0.1880 0.2996 0.1880 8.4863 0.4490 0.8174 0.0000 0.1537 0.0000 8.4863 0.0000 0.0000 0.0000 EXAMPLE # 4 LAS FILE FOR TIME BASED DATA ~VERSION INFORMATION VERS. 2.0 : CWLS LOG ASCII STANDARD -VERSION 2.0 WRAP. NO : ONE LINE PER TIME STEP # ~WELL INFORMATION STRT .S 0.0000 :START TIME STOP .S 1.5000 :STOP TIME STEP .S 0.3000 :STEP NULL . -999.25 :NULL VALUE COMP . ANY OIL COMPANY INC. :COMPANY WELL . ANY ET AL 12-34-12-34 :WELL FLD . WILDCAT :FIELD LOC . 12-34-12-34W5 :LOCATION PROV . ALBERTA :PROVINCE SRVC . ANY LOGGING COMPANY INC. :SERVICE COMPANY DATE . 13-DEC-86 :LOG DATE UWI . 100123401234W500 :UNIQUE WELL ID # ~CURVE INFORMATION ETIM.S : 1 ELAPSED TIME BFR1.OHMM : 2 SINGLE PROBE 1 RESISTIVITY BSG1.PSIG : 3 SINGLE PROBE 1 STRAIN GAUGE PRESSURE # ~PARAMETER INFORMATION MRT .DEGC 67.0 : BOTTOM HOLE TEMPERATURE GDEPT .M 3456.5 : GAUGE DEPTH DFD .KG/M3 1000.0 : MUD WEIGHT # ~A 0.0000 0.2125 16564.1445 0.3000 0.2125 16564.1445 0.6000 0.2125 16564.2421 0.9000 0.2125 16564.0434 1.2000 0.2125 16564.0430 1.5000 0.2125 16564.0435