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GeolOil - List of standard LAS curve Mnemonics dictionary


A Curve Mnemonic is the name of the curve in a LAS file. It must be a short single word with two or more letters, numbers, and optional underscores. In GeolOil, the mnemonics must satisfy these conditions:

  1. The mnemonic must start with a letter.

  2. No white, blank spaces, tabs, or any special characters are allowed. However, underscore characters "_" are allowed.

  3. The mnemonics can freely combine uppercase and lowercase letters. However, prefer uppercase letters for maximum compatibility between different software vendors. Detection of mnemonics are case insensitive.

  4. Non unique mnemonics are allowed in the same LAS file. Different LAS curves can have the same mnemonic —unfortunately it is quite common and confusing—. However, it is a bad practice to use the same mnemonic for different curves.

It is virtually impossible to provide a complete collection of "standard" curve mnemonics. They can be counted by hundreds or even thousands, and growing. Each logging company assigns its own mnemonics, and each interpreter usually assigns its own mnemonics, with versions and initials. It is normal.


An Alias is a short meaningful word —with the same rules as the mnemonics— intended to simplify the broad diversity of mnemonics curves. For instance, several LAS files can easily have many curve mnemonics for Gamma Ray, like GR, GR1, GAMMA, GR3, all of the them with similar properties and different qualities and resolutions. An alias simply called GammaRay could be a candidate for such collection of mnemonics.


The following list is our recommended collection of aliases for typical mnemonics. It is far from exhaustive, but usually gives an idea of the meaning of commonly encountered curves:


Table of standard LAS Curve Mnemonics dictionary

GeolOil Alias Descrip.

Mnemonic equivalents

BitSize Size of the drilling bit

BIT, BITS, BS, BitSize

Caliper Size of the Caliper

CALIPER, CALIP, CALI, CAL, DCAL, ACAL, CALA, CALD, CALE, CALH, CALL, CALM, CALML, CALN, CALP, CALS, CALT, CALX, CALXH, CALXZ, CALY, CALYH, CALYHD, CALYM, CALYQH, CALYZ, CALZ, CANC, CANN, CAPD, CAX, CAY, CLDC, CLDM, CLL0, CLMR, CLMS, CLRM, CLS2, CLTC, CLXC, CLXF, CLYC, MCAL, CALXQH, CLCM, CR1, CR2, CS1M, CS2M, CS3M, CS4M, CS5M, CS6M0, HCA1, HCAL, HCALI, HCALX, HCALY, XCAL, YCAL, CABX, CABY, CACN, CADF, CADP, CAMR, CAXR, CAYR, DCCP, MLTC, C1, C13, C13A, C13H, C24A, C24, C24H, C24I, C24L, C24M, C24P, C24Z, CA, CA1, CA2, CADE, CAL1, CAL2, CAL3, CALXM, CALXQ8, CALXGH, CALYQ8, CLCD, CLLO, CQLI, HD1, HD2, HD3, HDAR, HDIA, HDMI, HDMN, HDMX, HLCA, LCAL, SA, TAC2, C3, HHCA, MBTC, TACC, DZAL

BoreHTemp Borehole Temper.

TEMPERATURE, TEMPERAT, TEMPER, TEMP, TEXD, TEXF, BHT, BHTF, TEPP, TEXL, TEXM, TEXN, TEXP, GTEM, BoreHTemp

SP Spont. Potential

SP, IDSP, SPR, SPL, SPDL, SPDHP, SPDH, SPDF, SPD, SPCG, SPC, SP0, SP1, SPBR, SPBRDH, IASP, CGSP, DLSP, SPLL

GR Total Gamma Ray

GR, CGGR, CGR, DLGR, ECGR, EHGR, HRGR, GAM, GAMD, GAMM, GAMMA, GAMMARAY, GAMNAT, GCGR, GCPS, GRA, GRAY, GRC, GRCD, GRCF, GRD, GRDE, GRDI, GRG, GRGC, GRGM, GRGM, GRGS, GRH, GRHD, GRHDIL, GRI, GRIN, GRLL, GRM, GRML, GRN, GRNC, GRNP, GRP, GRPD, GRPND, GRQH, GRS, GRSD, GRSG, GRSL, GRT, GRTO, GRX, GRZ, GSGR, HGR, HSGR, LGR, P01LGR, P02LGR, P03LGR, P06LGR, PGR, SGR, SGRA, SGRB, SGRC, RGR, HCGR, GAMMA_RAY, GAMS, GRCR, GRHR, GRQA, GRR, GRV, MCGR, GRCN, GRDP, GRCC, GRCG, GRCL, GRCM, GRCP, GRD4, GRFB, GRMN, GRNB, GRPO, GRPR, GRRF, TGR, TOTGR, GRTOR, GR1, GR2, GRCO, GRDA, GRZD, HHGR, MGR, SGRD

GrUr Uranium Gamma Ray

URANIUM, URAN, URA, GRU, GRUR, HURA, U, UCPS, UZ

GrTho Thorium Gamma Ray

THORIUM, THOR, THO, GRTH, TH, HTHO, TCPS

GrPot Potassium Gamma Ray

POTASSIUM, POT, GRPO, GRPOT, GRPOTA, POTA, HPOT, KCPS

PEF Photo Electric Factor

PE, PEF, PEFZ, PDPE, PEDF, PEDN, HPEDN, HPEH8, PE2, PE2QH, PEF8, PEFA, PEFI, PEFL, LPE, PEFS

RHOB Bulk Density

RHOB, RHOZ, DEN, DENB, DENC, DENCDL, HRHO, HRHOB, ZDEN, ZDENS, ZDNCS, ZDNC, HDEN, DENF, DENN

DensCorr Bulk Density Correction

DCOR, DCORR, DC, DECR, DRH, ZCOR, ZCORR, ZCOR2, ZCOR2QH, ZCORQH, HHDR, DensCorr

PhiE Effective Porosity

PHIE, PIGN, POROE, DPHIE, NPHIE, SPHIE

PhiT Total Porosity

PHIT, POROT, DPHI, SPHI, XPOR, DPOR, NPOR, SPOR

NeutPhi Neutron Porosity

CN, PHIN, CNC, CNS, HHNPO, HNPHI, NPHI, NPOR, CNCC, CNCD, CNCF, NPRL, TNPH, TPHC, XPOR, NEUT, NeutPor

NPorLim Limestone Neutron Porosity (Calcite calibrated)

NPRL, NPORL, NPHIL, HNPOL, HNPO_LS, HNPO_LIM, NPOR_L, NPOR_LS, NPOR_LIM, HTNP_LIM, HNTP_LS, TNPH_LIM, NPorLim

NPorDol Dolomite Neutron Porosity (Dolomite calibrated)

NPRD, NPORD, NPHID, HNPOD, HNPO_DL, HNPO_DOL, NPOR_L, NPOR_DL, NPOR_DOL, HTNP_DOL, HNTP_DL, TNPH_LIM, HNTP_DOL, NPorDol

NPorSand Sandstone Neutron Porosity (Quartz calibrated)

NPRS, NPORS, NPHIS, HNPOS, HNPO_SS, NPOR_S, NPOR_SS, HNTP_SS, TNPH_SAN, HNTP_SAN, HNPO_SAN, NPOR_SAN, NPorSand

DtComp Compress. Delta Time (Slowness)

DT, DTC, DTCO, DTCOMP, DELTAT, SLOW, SLOWNESS, TT, TIME, TIM, ITT, DTCQI, DTCR, DTCREP, DTCS, DTCSG, DTCU, DTCV0, DTCX, DTL, DTP, DTR, DTTP, DTU, DTUM, CTIME, COTIME, COMT, DT1A, DT1B, DT34, DT35, DT3A, DT3B, DT45, DT46, DT56, DTC1, DTC2, DTC3, DTCM, AC, ACCO, DELT, ACL, ACN, DT24, DT24QI, DT24SQA, DT41, DT4P, DT5, DTMN, DTMX, DTSC, TTC, AC1, MSTT, DtComp

DtShear Shear Delta Time

DTS, DTSH, DTSM, DTSC, DTSD, DTSDF, DTSQI, DTTS, DTSHEAR, DELTAS, TTS, TIMES, TIMS, ITTS, STT, DT4S, DTSF, DTSS, SHSL, DtShear

Rxo Flushed Zone Resistivity

RXO, RXOZ, MSFL, MCFL, SFLCC, MGL

Rt True Deep Resistivity

RT, RTAO, RT1DI, RT90, ILD, IDER, IDFL, IDID, IDPH, IDVR, ILS, RILD, RIPD, RILV, RD, DEEP, AE90, AF90, AHFRT, AHO90, AHORT, AHRT, AHT90, AHTRT, AIRD, AO90, AORT, AS90, ASF90, ASFRT, ASRT, AST90, ASTRT, AT90, ATRT, DSER, HILD, HLLD, HRLD, LLD, LLDC, VRSD, SEDC, SEDA, RLLD, RES, RESD, REID, DLL, DDLL, HDRS, R850, MINV, ML

SWe Effective Water Saturation

SW, SWE, SWM, SWWW, WAT_SAT

SWt Total Water Saturation

SWT, SWTOT, SWTOTAL, SW_T, SW_TOT, SW_TOTAL

SWirr Irreduc. Water Saturation

SWirr, SWir, SWI, SWC

Vshale Volume of Shale

VSH, Vshale

Vclay Volume of Clay

Vclay, Vcla, Vcl

KhMax Maximum Horizontal Permeab.

KHMAX, KH, KMAX, KHMA, KHOR, PERM, HPERM, PERMH, MAX_PERM, KhorMax

KhMin Minimum Horizontal Permeab.

KHMIN, KMIN, KHMI, MINPERM, MIN_PERM, KHOR_MIN, KhorMin

Kvert Vertical Permeab.

KVERT, KVER, KVE, KV, VPERM, PERMV, VERTK, VERK

GeolOil default LAS curve Mnemonics dictionary


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