Crain's Petrophysical Handbook - Total Organic Carbon (TOC).pdf

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Crain's Petrophysical Handbook - Total Organic Carbon (TOC)

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TOTAL TOT AL ORGANIC CARBON

Terms Of Use / Disclaimer Site Navigation TOTAL ORGANIC CARBON (TOC) BASICS (TOC) Pay Shareware Fee Organic carbon in the form of kerogen is the remnant of ancient life Handbook Index / Site Map preserved in sedimentary rocks, after degradation by bacterial and Free Spreadsheet Downloads chemical processes, and further modified by temperature, pressure, and Free Publications time. The latter step, called thermal maturation, is a function of burial Testimonials history (depth) and proximity to heat sources. Maturation provides the About The Author needed to give us gas, oil, bitumen, pyrobitumen, and chemical reactions graphite (pure carbon) that we find while drilling wells for petroleum. eum.

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Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Visu al Analysis Of Logs For TOC Petrophysical Training Organic carbon is usually associated with shales or silty shales, but shales, but may Basic Bas ic TOC Log Calculations beWebinar present Dates in relatively clean siltstone, sandstone, and carbonate carbonate rocks. Ker ogen ogen Density Course Dates Kerogen Volume Order AV Courses A source rock is a fine grained sediment rich in organic matter that that could generate csrude crude oil orFrom natural gas after Gas Ga Content TOC Order Video Courses thermal alteration of kerogen in the Earth's crust. The oil or gas could then migrate from thePassey sourceDlogR rock to more TOC from Or der d erand Refer ence Manuals ence porous poro us permeable permeable sediments, where ultimately the oil or gas could accumulate to make a commercial oil or Method Become Be An Associate An gas r come eservoir. eservoir. TOC from Issler Crossplot Instructor Method If a source rock has not been exposed to temperatures of about 100 °C, it is termed a potential source rock. If TOC Spreadsheet TOC Spreadsheet Examples generation gene ration and expulsion expul of oil or gas have occurred, it is termed termed an actual source r ock. ock. The terms immature and Petrophysical Pet rophysical Cosion Consulting nsulting TOC TO C from Spectral GR Method mature mature are commonly used commonly used to describe source rocks and also the current state of the the kerogen contained in the TOC from ECS Method Consulting Co nsulting Services rock. TOC Log Analysis Examples Client Cli ent List Pro ject List carbon List Total organic carbon (TOC) as measured by laboratory techniqu techniques es historically historically has been used to assess the quality quality of source source rocks, but now is widely used to help evaluate evaluate some unconventiona unconventionall reservoirs reservoirs (reservoirs that are both source and productive). Totall Organic Tota Organic Carbon TOC Coall Analysis Coa Analysis Pathways that convert liv ingMethane organisms to Coal living Bed Bed Analysis organi rganic c carbon, from "Bit "Bitumen umens, Shale Sh ale Gas Gs, asAsphalts, Analysis and Tar Sands" ands" by George V. V. Chilingar , Teh Yen,Analysis 1978. 1978. Immature Immatu re OilFu Shale Tightt Gas Tigh Gas Analyzis Tight Oil Oil / Shale Oil Analyzis

In the lab, it is relatively easy to distinguish kerogen from hydrocarbons: kerogen is insoluble in organic solvents, oil and bitumen are soluble. Pyrobitumen is not soluble but its hardness is used to identify it from kerogen. Graphite is evident on resistivity logs because of the very low resistivity; all other forms of organic carbon are resistive. Organic carbon has a density near that of water, so it looks like porosity to conventional porosity logs. High resistivity with some apparent porosity on a log analysis is a good indicator of organic carbon content OR ordinary hydrocarbons OR both.

TYPES OF KEROGEN https://spec2000.net/11-vshtoc.htm

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Organic material can be classified according to the source of the material, as shown below.


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TOTAL TOT AL ORGANIC CARBON (TOC)

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Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Analysis Of Logs For TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates Kerogen Volume Order AV Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Method TOC Spreadsheet Examples Origin, type, source, and hydrocarbon potential of different kerogens. Organic content in gas shales is usually Petrophysical Consulting TOC from Spectral GR Method Type II, as opposed to coals, which contain mostl y Type III TOC from ECS Method Consulting Services TOC Log Analysis Examples Client List The most commonly utilized scheme for classifying organic matter in Project List sediments is based on the relative abundance of elemental carbon, oxygen, and hydrogen plotted graphically as the H/C and O/C ratio on a so called Van Krevelen diagram.

The classic Van Krevelen diagram Rather than plot the elemental ratios it is common to plot indices determined by a pyrolysis technique referred to as Rock Eval. In the pyrolysis techniques two indices are determined: the Hydrogen Index (HI) which is mi lligrams of pyrolyzable hydrocarbons divided by TOC and the Oxygen Index (OI) which is milligrams of pyrolyzable organic carbon dioxide divided by TOC.

Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Shale Gas Analysis Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis

Cross-plots of both elemental H/C and O/C ratios or of HI and OI are utilized to discriminate four ‘ fields’ which are referred to as Types I, II, III, and IV kerogen. Type I kerogen is hydrogen rich (atomic H/C of 1.4 to 1. 6: HI of > 700) and is derived predominantly from zooplankton, phytoplankton, micro-organisms (mainly bacteria) and lipid rich components of higher plants (H/C ratio 1.7 to 1.9). Type II kerogen is intermediate i n composition (H/C ≈ 1.2: HI ≈ 600) and derived from mixtures of highly degraded and partly oxidized remnants of higher plants or marine phytoplankton. Type III kerogen is hydrogen poor (H/C ratio 1.3 to 1.5) and oxygen rich and is mainly derived from cell ulose and lignin derived from higher plants. Type IV kerogen is hydrogen poor and oxygen rich and essentially inert. This organic matter is mai nly derived from charcoal and fungal bodies. Type IV kerogen is not always distinguished but is grouped with Type III. https://spec2000.net/11-vshtoc.htm

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The different types of organic matter are of fundamental importance since the relative abundance of Welcome hydrogen, carbon, and oxygen determines whatTo products can be generated from the organic mat ter upon diagenesis. Since coal is comprised predominantly of Type III kerogen, there is lit tle liquid hydrogen generating capacity. If the coal includes abundant hydrogen rich components (such as spores, pollen, resin, waxes - Type I or II), it will generate some liquid hydrocarbons. Although not common, some oil deposits are Handbook Index Training About the Author Terms of Use Contact Us Search thought to be sourcedPetrophysical by coals.

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THIS IS A SHAREWARE SITE. PLEASE BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE Note: Portions of the above Section, and the next Section, were taken verbatim (with moderate editing) from CBM Solutions reports. TOTAL ORGANIC CARBON Terms Of Use / Disclaimer Site Navigation Quick Links (TOC) Pay Shareware Fee Total Organic Carbon (TOC) Handbook Index / Site Map Basics ANALYZING TOC IN THE LABORATORY Free Spreadsheet Downloads Types Of Kerogen The total organic carbon content of rocks is obtained by heating the rock in a furnace and combusting the Free Publications Analyzing to TOC The Labof organic matter to carbon dioxide. The amount of carbon dioxide liberated is proportional theInamount Testimonials Geochemical Logs carbon liberated in the furnace, which in turn is related to the carbon content of the rock. The carbon dioxide About The Kerogen Maturity liberated canAuthor be measured several different ways. The most common methods use a thermal conductivity Visual Analysis Of Logs For detector or infrared spectroscopy. TOC Petrophysical Training Basic Calculations Many source rocks also include inorganic sources of carbon such as carbonates and TOC mostLog notably calcite, Webinar Dates dolomite, and siderite. These minerals break down at high temperature, generating carbon dioxide and thus Kerogen Density Course Datesmust be corrected in order to determine t he organic carbon content. Generally, the amount of their presence Kerogen Volume Order AVis Courses carbonate determined by acid digestion (normally 50% HCl) and the carbon dioxide generated measured Gas Content FromisTOC Order Video Courses and then subtracted from the total carbon dioxide to obtain the organic fraction.TOC from Passey DlogR Order Reference Manuals Method Become An carbon Associate Total organic is often taken to mean the same thing as kerogen, but this isTOC not from the case. is made IsslerKerogen Crossplot upInstructor of oxygen, nitrogen, sulphur, and hydrogen, in addition to carbon. The standard pyrolysis lab procedure Method measures only the carbon, so total organic carbon excludes the other elements. TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method About 80% of a typical kerogen (by weight) is carbon, so the weight fraction of TOC isfrom 80%ECS of the kerogen TOC Method Consulting Services weight. The factor is lower for less mature and higher for more mature kerogen: TOC Log Analysis Examples Client List= Wker * KTOC 1: Wtoc Project List OR 2: Wker = Wtoc / KTOC Where: Wtoc = weight fraction of organic carbon Wker = weight fraction of kerogen KTOC = kerogen correction factor - range = 0.68 to 0.90, default 0.80

Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Shale Gas Analysis Immature Oil Shale Analysis Another lab procedure, called RockEval, burns both hydrogen and carbon, so theTight data Gas needs to be calibrated to Analyzis the standard method by performing a chemical analysis on the kerogen. TypicallyTight the organic carbon needs to be Oil / Shale Oil Analyzis reduced by about 10% (the weight of the hydrogen burned) to match the standard method.

Rock Eval is the trade name for a set of equipment used in the lab to m easure organic content of rocks, as well as other properties of the organics that help to identify the kerogen type. Rock-Eval combusts a crushed sample of rock at 600ºC. Refractory organic matter such as inertinite does not combust readily at 600ºC so most coal samples yield Rock-Eval measured TOC values much lower than actual values because of incomplete combustion. Rock-Eval is not recommended for use with coals or source rocks with signif icant amounts of Type III and IV kerogen. A rock sample is crushed finely enough so that 85% falls through a 75 mesh screen. Approximately 100 mg of sample is loaded into a stainless steel crucible capped with a micro mesh filter. To ensure accuracy, standard samples are loaded at the beginning and end of the run. Any drift in data can be detected and the samples rerun if necessary. The analyzer consists of a flame ionization detector and two IR detector cell s. The free hydrocarbons (S1) are determined from an isothermal heating of the sample at 340 degrees Celsius. These hydrocarbons are measured by the flame ionization detector. The temperature is then increased from 340 to 640 degrees Celsius. Hydrocarbons are then released from the kerogen and measured by the fl ame ionization detector creating the S2 peak. The temperature at which S2 reaches its maximum rate of hydrocarbon generation is referred to as Tmax. The CO2 generated from t he oxidation step in the 340 to 580 degrees Celsius is measured by the IR cells and is referred to the S3 peak.

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Measured results from a typical Rock Eval study will contain: TOC% - Weight percentage of organic carbon To S1 = amount of free hydrocarbonsWelcome in sample (mg/g) S2 = amount of hydrocarbons generated through thermal cracking (mg/g) – provides the quantity of hydrocarbons that the rock has the potential to produce through diagenesis. Training Handbook Index Petrophysical About the Author Terms of Use Contact Us Search S3 = amount of CO2 (mg of CO2/g of rock) - reflects the THIS IS SHAREWARE SITE. PLEASE amount of A oxygen in the oxidation step. BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE Ro = vitrinite reflectance (%) TOTALrate ORGANIC CARBON Tmax = the temperature at which m aximum of Terms Of Use / Disclaimer Site Navigation Quick Links generation of hydrocarbons occurs. (TOC) Pay Shareware Fee Total Organic Carbon (TOC) Handbook Index / Site Map Basics Calculated results include: Free Spreadsheet Downloads Types Of Kerogen Hydrogen index Free Publications Analyzing TOC In The Lab 1: HI = 100 * S2 / TOC% Testimonials Geochemical Logs Oxygen index About Author 2: OI The = 100 * S3 / TOC% Kerogen Maturity Production index Visual Analysis Of Logs For 3: PI = S1 / (S1 + S2) TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Depth (m) SRA Tmax Meas. Course Dates TOC HI OI Kerogen S2/S3 Volume PI Order TopAV Courses S1 S2 S3 (°C) % Ro S1/TOC*100 Gas Content From TOC Order X025Video Courses 1.35 0.05 1.72 0.63 444 128 47 TOC from 3 Passey4 DlogR 0.03 Order Manuals X040Reference 1.18 0.05 1.65 0.57 443 140 49 4 0.03 Method 3 Become An Associate X050 0.83 0.03 1.31 0.55 443 158 66 TOC from 2 4 0.02 Issler Crossplot Instructor X065 0.80 0.04 1.00 0.58 440 126 73 5 0.04 Method 2 X075 0.75 0.05 1.04 0.72 438 138 96 TOC Spreadsheet 1 7 Examples 0.05 Petrophysical Consulting TOC from Spectral GR Method X090 1.04 0.09 2.52 0.29 452 241 28 9 9 0.03 TOC from ECS Method Consulting Services X110 1.02 0.05 1.16 0.56 441 114 55 2 5 0.04 Client X135List 1.05 0.05 1.32 0.57 443 125 54 TOC Log 2 Analysis 5 Examples 0.04 Project List Laboratory measured TOC values (weight %) with measured and computed indices

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HI versus OI plot example, indicating Type III kerogen An alternate method for measuring TOC by solution rather than pyrolysis is described below, from a 1980's TOC report from Australia.

"The samples are analyzed for total organic carbon (TOC) according to AS 1038 Part 6. Moisture determinations are made to permit conversion to a dry basis. Carbon occurring as carbonate ion is determined to correct the gross carbon data to give the organic carbon content. This is done by driving off carbonate minerals with HCl acid. The crushed and sieved (100 mesh) samples are weighed and exhaustively extracted in a Soxhlet apparatus using a benzene-methanol mixture. After removal of methanol by azeotropic distillation with benzene, the https://spec2000.net/11-vshtoc.htm

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residue in benzene is diluted with hexane and the hydrocarbon solution separated by filtration from t he brown precipitate. The latter is then dissolved in methanol. The yield of methanol soluble material is determined Welcome To gravimetrically.

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silica. Elution with hexane gives predominantly alkanes and subsequent elution with hexane/benzene yields mainly monocyclic polycycllc aromatic The eluted Terms hydrocarbons weighed, Handbook Index and Petrophysical Training hydrocarbons. About the Author of Use areContact Usand then Search analyzed by gas chromatography / mass spectrometry." THIS IS A SHAREWARE SITE. PLEASE BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE

TOTAL ORGANIC CARBON

GEOCHEMICAL LOGS Terms Of Use / Disclaimer Site Navigation Quick Links (TOC) Measured and calculated indices can be plotted versus depth; the resulting log Total is called a Geochemical Log. Pay Shareware Fee Organic Carbon (TOC) Handbook Index / Site Map Basics Free Spreadsheet Downloads Types Of Kerogen Free Publications Analyzing TOC In The Lab Testimonials Geochemical Logs About The Author Kerogen Maturity Visual Analysis Of Logs For TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates Kerogen Volume Order AV Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Method TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method TOC from ECS Method Consulting Services TOC Log Analysis Examples Client List Project List



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Petrophysical Training Webinar Dates Course Dates Order AV Courses Order Video Courses Order Reference Manuals Become An Associate Instructor

Petrophysical Consulting Consulting Services Client List Project List

TOTAL ORGANIC CARBON (TOC)

Quick Links Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Analysis Of Logs For TOC Basic TOC Log Calculations Kerogen Density Kerogen Volume Gas Content From TOC TOC from Passey DlogR Method TOC from Issler Crossplot Method TOC Spreadsheet Examples TOC from Spectral GR Method TOC from ECS Method TOC Log Analysis Examples


A geochemical log from offshore East Coast Canada


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KEROGEN MATURITY The hydrocarbon potential of organic carbon depends on Welcome To the thermal history of the rocks containing the kerogen. Both temperature and the time at that temperature determine the outcome. Medium temperatures (< 175 C) produce mostly oil and a lit tle gas. Warmer temperatures Handbook Index About the Author produce mostly gas. Petrophysical Training

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THIS IS A SHAREWARE SITE. PLEASE BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE Hydrocarbon type versus temperature defines "oil window" and "gas window", TOTAL ORGANIC CARBON Terms Of Use / Disclaimer Site Navigation Quick Links with some obvious overlap(TOC) Pay Shareware Fee Total Organic Carbon (TOC) Handbook Index / Site Map Basics Vitrinite reflectance (Ro) is used as an indicator of the Free Downloads Types Of Kerogen level ofSpreadsheet organic maturity (LOM). Ro values between 0.60 Free Publications and 0.78 usually represent oil prone intervals. Ro > 0.78 Analyzing TOC In The Lab Testimonials usually indicates gas prone. High values can suggest Geochemical Logs Aboutspots" The Author "sweet for completing gas shale wells. Kerogen Maturity Visual Analysis Of Logs For Measurement of vitrinite reflectance was described as TOC Petrophysical Training follows from the 1980's TOC report. Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates "Sample chips or sidewall core samples are cleaned t o Kerogen Volume Order AV Courses remove drilling mud or mud cake and t hen crushed Gas Content From TOC Order Video Courses using a mortar and pestle to a grain-size of less than 3 TOC from Passey DlogR Order Reference Manuals in cold-setting resin and mm. Samples are mounted Method Become''as Anreceived", Associate so that whole-rock samples polished TOC from Issler Crossplot Instructor rather than concentrates of organic matter are examined. Method This method is preferred to the use of demineralized TOC Spreadsheet Examples concentrates because of the greater ease of identifying Petrophysical Consulting TOC from Spectral GR Method first generation vitrinite and, for cuttings samples, of TOC from ECS Method Consultingcavings. ServicesThe core samples are mounted and recognizing TOC Log Analysis Examples Client List sectioned perpendicular to the bedd1ng. Project List

Vitrinite reflectance measurements are made using immersion oil of refractive index 1.518 at 546 nm and 23°C and spinel and garnet standards of 0.42%, 0.917% and 1.726% reflectance for calibration. Fluorescence-mode Total Organic Carbon TOC observations are made on all samples and provide supplementary evidence concerning organic matter type, Coal Analysis and exinite abundance and maturity. For fluorescence-mode a 3 mm BG-3 excitation filter is usedAnalysis with a Coal Bed Methane TK400 dichroic mirror and a K490 barrier filter." Shale Gas Analysis Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis Graphs of HI vs Ro and HI vs Tmax are used to help refine kerogen type and to assess maturity with respect to the oil and gas "windows". Depth plots of Ro and Tmax are helpful in spotting the top of the oil or gas window in specific wells, and in locating sweet spots for possible production using horizontal wells. Tmax is also a useful indicator of maturity, higher values being more mature.


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Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Analysis Of Logs For TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates Kerogen Volume Order AV Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Method TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method Crossplots of HI vs Tmax and HI vs Ro determine organic maturity, kerogen type, and whether the TOC from ECS Method Consulting rock is in the Services oil or gas window. Immature and post mature rocks are not overly interesting as possible source TOC Log Analysis Examples orClient reservoir List rocks. Project List



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Total Organic Carbon TOC Depth plot of Ro to determine trend line and location of oil and gas windows (Ro > 0.55). Coal Analysis Ro is plotted on a logarithmic scale, which makes the trend line relatively straight. Coal Bed Methane Analysis Shale Gas Analysis Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis


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Thermal maturity as indicated by vitrinite reflectance (Ro) versus depth for a Barnett shale, showing "sweet spot" and oil versus gas “windows”.


VISUAL ANALYSIS OF TOC FROM LOGS

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Visual analysis for organic content is based on About the Author Handbook Index Petrophysical Training Terms of Use Contact Us Search the porosity - resistivity overlay technique, widely locate possible hydrocarbon THISused IS A to SHAREWARE SITE. PLEASE BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE shows in conventional log analysis. By extending the method to radioactive zones TOTAL ORGANIC CARBON Terms Ofrelatively Use / Disclaimer Site Navigation Quick Links instead of clean zones, organic rich (TOC) Pay Shareware Fee shales (potential source rocks , gas shales, oil Total Organic Carbon (TOC) Handbook Index / Site Map shales) can be identified. Usually the sonic log Basics Downloads is Free usedSpreadsheet as the porosity indicator but the Types Of Kerogen neutron or density log would work as well. Free Publications Analyzing TOC In The Lab Testimonials Geochemical Logs The trick here is to align the sonic log on top About The Author Kerogen Maturity of the logarithmic scale resistivity log so that Visual Analysis Of Logs For the sonic curve lies on top of the resistivity TOC Petrophysical Training curve in the low resistivity shales. Low Basic TOC Log Calculations Webinar shales Dates are considered to be nonresistivity Kerogen Density source rocks and are unlikely to be gas Course Dates Kerogen Volume shales. or silts with source rock OrderShales AV Courses Gas Content From TOC potential will show considerable crossover Order Video Courses TOC from Passey DlogR between the sonic and resistivity curves. The Order Reference Manuals Method absolute of the sonic and resistivity in Becomevalue An Associate TOC from Issler Crossplot the low resistivity shale are called base-lines, Instructor Method and these base-lines will vary with depth of TOC Spreadsheet Examples burial and geologic age. Petrophysical Consulting TOC from Spectral GR Method TOC from ECS Method Schematic logServices showing sonic resistivity Consulting TOC Log Analysis Examples Client in List overlay a variety of situations Project List

Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Sonic resistivity overlay showing crossover in Barnett Gas Analysis Shale, Texas, labeled " ΔlogR" andShale shaded red. Immature Oil Shale Analysis Tight Analyzis Crossplots of porosity and logarithm of Gas resistivity can also be Tight Oil / Shale Oil Analyzis used to define and segregate source rocks from non-source rocks. See "Identification of Source Rocks on Wireline Logs by Density-Resistivity and Sonic-Resistivity Crossplots" by B. L. Meyer and M. H. Nederlof, AAPG Bulletin, V. 68, P 121-129, 1984..The best description of the method is posted on the online magazine Search and Discovery , in "Direct Method for Determining Organic Shale Potential from Porosity and Resistivity Logs to Identify Possible Resource Plays* by Thomas Bowman, Article #110128, posted June 14, 2010. These crossplots usually show a non-source rock trend line on the southwest edge of the data (similar to the water line on a Pickett plot) and a cluster of source rock data to the right of the non-source line, as shown in the image below. The slope and intercept of the non-source line is used to calculate a pseudosonic log, DtR, from the resistivity log, which can then be plotted on the same scale as the original sonic log.


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Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Analysis Of Logs For TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates Kerogen Volume Order AV Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Method TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method TOC from ECS Method Consulting Services TOC Log Analysis Examples Client List Sonic versus logarithm of resistivity (DlogR) Crossplot showing non-source rock trendline and source rock Project List cluster of data. The equation of the non-source rock line is DtR = 105 - 25 log(RESD) for this Barnett Shale example. Total Organic Carbon TOC Coal Analysis As for the manual overlay technique described Coal Bed Methane Analysis above, crossover indicates source rock potential, shale gas, or an oil shale, or if the Shale Gas Analysis zone is clean, a potential hydrocarbon pay Immature Oil Shale Analysis zone. An example of a DtR log is shown below. Tight Gas Analyzis Tight Oil / Shale Oil Analyzis Original sonic log (left edge of red shading) and calculated DtR curve (black curve) showing potential source rock or, as in this case, gas shale (Barnett)

BASIC ANALYSIS OF TOC FROM LOGS A wide variety of log analysis methods are used to calculate total organic carbon from well logs, ranging from https://spec2000.net/11-vshtoc.htm

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over-simplified to complex multi-mineral probabilistic models. The Passey and Issler models, described later, are in the middle of the pack for complexity. We also need to convert lab data into volumetric terms for comparison to log analyis results. This Section Welcome coversd someTo of these steps.

TOC from Density Log Data

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Correlation of core TOC values to log data leads to useful relationships for specific reservoirs. A strong Handbook Index Petrophysical Training About the Author Terms of Use Contact Us Search correlation exists in some shales with Uranium content from the spectral gamma ray log. In other cases, the relationship made with density, resistivity, gamma ray, or combinations of these curves. Variations in THIS IS A is SHAREWARE SITE. PLEASE BE sonic, FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE matrix mineralogy strongly affect this type of correlation and it is possible that mineralogy will mask any trend with TOC. The crossplot shown belowTOTAL is for a particular well inCARBON the Barnett shale. ORGANIC Terms Of Use / Disclaimer Site Navigation Quick Links (TOC) Pay Shareware Fee Carbon (TOC) Correlation ofTotal TOCOrganic with density in Barnett Handbook Index / Site Map Basics Shale: Wtoc = -0.259 * DENS + 0.707. Similar Free Spreadsheet Downloads crossplots of sonicTypes or neutron Of Kerogen data can be used Free Publications for specific reservoirs where TOC TOC In data isLab available Analyzing The Testimonials from core. Geochemical Logs About The Author Kerogen Maturity Visual Analysis Of Logs For TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates Kerogen Volume Order AV Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Plot in Avalon Shale: Wtoc = -0.1324 * DENS + 0.754 Method TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method TOC from ECS Method Consulting Services TOC Log Analysis Examples Client List Project List

KEROGEN DENSITY Kerogen density is difficult to measure directly but can be inferred from a plot of Total (inverse) coreCarbon grain density Organic TOC versus TOC weight percent or mass fraction. This value is needed to find kerogenCoal volume fraction from kerogen Analysis weight fraction. The method also relies on the density versus TOC crossplot. Coal Bed Methane Analysis Shale Gas Analysis Plot to find TOC Immature specific Oilgravity Shale Analysis (DENStoc) and rock grain density using inverse Tight (DENSma) Gas Analyzis grain density on Y-Axis. Tight Oil / Shale Oil Analyzis On this graph, 1: DENSma = 1 / INTCPT = 1 / 0.37 = 2.703 g/cc 2: SLOPE = (0.409 - 0.37) / (9 - 0) = 0.004166 (from Excel spreadsheet) 3: DENStoc = 1 / (100 * SLOPE + INTCPT) = 1 / (100 * 0.004166 + 0.37) = 1.28 g/cc 4: DENSker = DENStoc / KTOC = 1.28 / 0.80 = 1.42 g/cc Where KTOC = kerogen correction factor - Range = 0.68 to 0.90, default 0.80

Typical values for DENSker are in the range 0.95 for immature to 1.45 for very mature, with a default of 1.26 g/cc. Because of the extrapolation from small TOC values up to 100% TOC, the possible error in DENStoc is quite large, so many people will choose a default based on the maturity of the kerogen.


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KEROGEN VOLUME



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Log analysis models need the volume fraction of kerogen, not the weight fraction. This is found from: 1: Wtoc = TOC% / 100 2: Wker = Wtoc / KTOC 3: VOLker = Wker /Petrophysical DENSker Handbook Index Training About the Author Terms of Use Contact Us Search 4: VOLmatrix = (1 - Wker) / DENSma 5: VOLrock = VOLker + VOLmatrix THIS IS A SHAREWARE SITE. PLEASE BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE 6: Vker = VOLker / VOLrock

TOTAL ORGANIC CARBON

Terms Use / Disclaimer Site Navigation There is aOfspreadsheet on the Downloads page that (TOC) Pay Shareware Fee does weight to volume and volume to weight Handbook Index Site Mapat right. Typically, Vker is a conversions -- see /example Free Spreadsheet Downloads little less than 2 * Wtoc. Free Publications Testimonials "META/WT-VOL" Spreadsheet. About The Author

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Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Analysis Of Logs For GAS CONTENT VERSUS TOC TOC Petrophysical Training TOC values calculated from log analysis models are widely used as a guide to theBasic quality of Log gas Calculations shales. Using TOC Webinar Dates correlations of lab measured TOC and gas content (Gc). We can use log analysis Kerogen derived TOC values to predict Density Course Gc, whichDates can then be summed over the interval and converted to adsorbed gas in place. Sample correlations Kerogen Volume are shown Order AVbelow. Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Method TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method TOC from ECS Method Consulting Services TOC Log Analysis Examples Client List Project List

Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Shale Gas Analysis Shale Analysis Crossplots of TOC versus Gc for Tight Gas / Shale Gas examples. Note the largeImmature variation Oil in Gc versus TOC for Tight Gas Analyzis different rocks, and that the correlations are not always very strong. These data sets are from core samples, Tight Oil / Shale Oil Analyzis cuttings give much worse correlations. The fact that some best fit lines do not pass through the origin suggests systematic errors in measurement or recovery and preservation techniques.

PASSEY'S "DlogR" METHOD Various multi-curve methods for quantifying organic content from well logs have been published, including multiple regression, probabilistic, and neural network solutions. The most common method is based on sonic versus resistivity, as described in "A Practical Model for Organic Richness from Porosity and Resistivity Logs" by Q. R. Passey, S. Creaney, J. B. Kulla, F. J. Moretti and J. D. Stroud, AAPG Bulletin, V. 74, P 1777-1794, 1990. It is also known as the "D log R" method (with or without spaces and hyphens between the characters). The "D" was originally the Greek letter Delta (ΔlogR). Although the sonic resistivity model is the best known version of the Passey method, density and neutron data can also be used, as shown below: 1: SlogR = log (RESD / RESDbase) + 0.02 * (DTC – DTCbase) 2: DlogR = log (RESD / RESDbase) -- 2.5 * (DENS – DENSbase) 3: NlogR = log (RESD / RESDbase) + 4.0 * (PHIN – PHINbase) 4: TOCs = SF1s * (SlogR * 10^(0.297 – 0.1688 * LOM)) + SO1s 5: TOCd = SF1d * (DlogR * 10^(0.297 – 0.1688 * LOM)) + SO1d 6: TOCn = SF1n * (NlogR * 10^(0.297 – 0.1688 * LOM)) + SO1n Where: https://spec2000.net/11-vshtoc.htm

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RESD = deep resistivity in any zone (ohm-m) RESDbase = deep resistivity baseline in non-source rock (ohm-m) Welcome DTC = compressional; sonic log reading in any To zone (usec/ft) DTCbase = sonic baseline in non-source rock (usec/ft) DENS = density log reading in any zone (gm/cc) DENSbase = density in non-source rock (gm/cc) PHIN = neutron in any zone (fraction) Handbook Indexlog reading Petrophysical Training About the Author Terms of Use Contact Us Search PHINbase = neutron baseline in non-source rock (fraction) THIS IS A SHAREWARE SITE. PLEASE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE numberBE from sonic, density, neutron log (fractional) SlogR, DlogR, NlogR = Passey’s LOM = level of organic maturity (unitless) ORGANIC TOCs,d,n = total organic carbon fromTOTAL Passey method (weightCARBON fraction) Terms Of Use / Disclaimer Site Navigation SF1s,d,n and SO1s,d,n = scale factor and scale offset to calibrate to lab values of TOC Quick Links (TOC) Pay Shareware Fee Total Organic Carbon (TOC) Handbook Index / Site Map Divide metric DTC values by 3.281 to get usec/ft, metric density by 1000 to getBasics gm/cc. Free Spreadsheet Downloads Types Of Kerogen Free Publications Analyzing TOC In The Lab in In practice, it is rare to have both TOC laboratory measurements and reliable organic maturity data to assist Testimonials calibration. Chose a value for LOM that will result in a match with available TOC data. Geochemical Vitrinite reflectance Logs (Ro) Aboutmay Thebe Author values available and are converted to LOM with the graph below. LOM is Kerogen typically Maturity in the range of 6 to 14. Default LOM for a gas shale is 8.5 and fir an oil shale is10.5. Visual Analysis Of Logs For TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Kerogen Density Course Dates Kerogen Volume Order AV Courses Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Method Become An Associate TOC from Issler Crossplot Instructor Method TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method TOC from ECS Method Consulting Services TOC Log Analysis Examples Client List

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Graph for finding Level of Organic Maturity from Vitrinite Reflectance. Higher LOM reduces calculated TOC. Some petrophysicists do not believe this chart, and use regression techniques on measured TOC to estimate LOM - see bottom illustration on this page for an example.

Numerical Example: RESD RESDbase DTC DTCbase LOM DENS DENSbase PHIN PHINbase 25 4 100 62 8.5 2.35 2.65 0.34 0.15 DTC DENS DlogR = 1.556 1.546 TOC = 0.113 0.113

PHIN 1.556 0.113 weight fraction

ISSLER'S METHOD Dale Issler published a model specifically tuned to Western Canada in "Organic Carbon Content Determined from Well Logs: Examples from Cretaceous Sediments of Western Canada" by Dale Issler, Kezhen Hu, John Bloch, and John Katsube, GSC Open File 4362. It is based on density vs resistivity and sonic vs resistivity crossplots (other methods are also described in the above paper).


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The crossplots were redrafted in Excel , as shown below, and a drop-through code developed to generate TOC, based on the lines on the graphs. No doubt there is a simpler way to code this, but I didn't have time to sort it Welcome To out.

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Quick Links Total Organic Carbon (TOC) Basics Types Of Kerogen Analyzing TOC In The Lab Geochemical Logs Kerogen Maturity Visual Analysis Of Logs For TOC Basic TOC Log Calculations Kerogen Density Kerogen Volume Gas Content From TOC TOC from Passey DlogR Method TOC from Issler Crossplot ◄ DTC vs RESD Method TOC Spreadsheet Examples TOC from Spectral GR Method TOC from ECS Method TOC Log Analysis Examples


DENS vs RESD ► Note that sonic and density data are in Metric units. TOC calculated from DENS vs RESD crossplot gives similar results to the sonic approach, but the density model should not be used in large or rough borehole intervals. Intervals where the sonic log is skipping should be edited before use. The "drop-through" code shown below gives integer values of TOC%, then coverts it to a decimal fraction. Multiple regression equations, developed by Tristan Euzen from the Issler graphs, give smooth (non-integer) values and are of course easier to code into petrophysical software or spreadsheet packages. Thanks for your work Tristan. https://spec2000.net/11-vshtoc.htm

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TOC_X - TOC FROM REGRESSION ANALYSIS OF ISSLER'S GRAPHS Tristan Euzen's multiple regression gives: Welcome To 7: TOCs = 0.0714 * (DTC + 195 * log(RESD)) - 31.86 8: Wtocs = SF2 * TOCs / 100 + SO2

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Equations for the density-resistivity model are not quite as neat. By linear regression, Tristan found: Handbook Index Petrophysical Training About the Author Terms of Use Contact Us 97: Intercept = 4.122 * Slope + 1014

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98: TOCd -0.1429 * Slope +SITE. 45.14PLEASE BE FAIR TO THE AUTHOR AND PAY YOUR SHAREWARE FEE HERE THIS IS A= SHAREWARE

Recognizing that: 99: DENS = Slope * Log(RESD) + Intercept TOTAL ORGANIC CARBON And by substuon: Terms Of Use / Disclaimer Site Navigation (TOC) 9: TOCd = -0.1429 + 45.14 Pay Shareware Fee* (DENS – 1014) / (log(RESD) + 4.122)

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Total Organic Carbon (TOC) 10: WtocdIndex = SF3/ Site * TOCd Handbook Map/ 100 + SO3 Basics Free Spreadsheet Downloads Types Of Kerogen Log analysis TOC results should be calibrated to lab measured TOC from real rocks. Scale factors and SF3 Free Publications Analyzing TOC In SF The2Lab and scale offset SO2 and SO3 are determined by regression of lab versus log derived TOC values. If you want Testimonials Geochemical Logs TOC%, remove the "/ 100" from equations 8 and 10. About The Author Kerogen Maturity Visual Analysis Of Logs For TOC_MR TOC FROM MULTIPLE LINEAR REGRESSION TOC Petrophysical Training Sometimes it is difficult to get a good match to measured TOC values using Passey or Issler methods. Some Basic TOC Log Calculations Webinar Dates software packages have multiple linera equation solvers. that can help. Here is a Kerogen typical solution Densityfor one Course Dates particular well where such a regression was run: Kerogen Volume Order AV Courses 11: TOCmr = - 3.73089 + 0.0259051 * DTC + 1.13726 * PHIN_SS + 0.877866 * log(RESD) Gas Content From TOC Order Video Courses - 0.000722865 * DENS TOC from Passey DlogR Order Reference Manuals Method NoBecome scale factor or scale offset is needed as the equation is derived from the measured data. An Associate TOC from Issler Crossplot Instructor Method TOC_S - TOC FROM SONIC RESISTIVITY CROSSPLOT TOC Spreadsheet Examples Petrophysical Consulting TOC from Sonic Resistivity Crossplot TOC from Spectral GR Method IFConsulting DELT <= (-195 * LOG(RESD) + 460) THEN TOCs = 0 TOC from ECS Method Services IFClient DELTList > (-195 * LOG(RESD) + 460) THEN TOCs = 1 TOC Log Analysis Examples IF DELT > (-195 * LOG(RESD) + 474) THEN TOCs = 2 Project List IF DELT > (-195 * LOG(RESD) + 488) THEN TOCs = 3 IF DELT > (-195 * LOG(RESD) + 502) THEN TOCs = 4 Total Organic Carbon TOC IF DELT > (-195 * LOG(RESD) + 516) THEN TOCs = 5 Coal Analysis IF DELT > (-195 * LOG(RESD) + 530) THEN TOCs = 6 Coal Bed Methane Analysis IF DELT > (-195 * LOG(RESD) + 544) THEN TOCs = 7 Shale Gas Analysis IF DELT > (-195 * LOG(RESD) + 558) THEN TOCs = 8 IF DELT > (-195 * LOG(RESD) + 572) THEN TOCs = 9 Immature Oil Shale Analysis IF DELT > (-195 * LOG(RESD) + 586) THEN TOCs = 10 Tight Gas Analyzis IF DELT > (-195 * LOG(RESD) + 600) THEN TOCs = 11 Tight Oil / Shale Oil Analyzis IF DELT > (-195 * LOG(RESD) + 614) THEN TOCs = 12 IF DELT > (-195 * LOG(RESD) + 628) THEN TOCs = 13 IF DELT > (-195 * LOG(RESD) + 642) THEN TOCs = 14 IF DELT > (-195 * LOG(RESD) + 656) THEN TOCs = 15 IF DELT > (-195 * LOG(RESD) + 670) THEN TOCs = 16 IF DELT > (-195 * LOG(RESD) + 684) THEN TOCs = 17 IF DELT > (-195 * LOG(RESD) + 698) THEN TOCs = 18 IF DELT > (-195 * LOG(RESD) + 712) THEN TOCs = 19 IF DELT > (-195 * LOG(RESD) + 726) THEN TOCs = 20 IF DELT > (-195 * LOG(RESD) + 740) THEN TOCs = 21 IF DELT > (-195 * LOG(RESD) + 754) THEN TOCs = 22 IF DELT > (-195 * LOG(RESD) + 768) THEN TOCs = 23 IF DELT > (-195 * LOG(RESD) + 782) THEN TOCs = 24 Wtocs = SF2 * TOCs / 100 + SO2

TOC_D - TOC FROM DENSITY RESISTIVITY CROSSPLOT IF DENS < (150 * LOG(RESD) IF DENS < (155 * LOG(RESD) IF DENS < (160 * LOG(RESD) IF DENS < (166 * LOG(RESD) IF DENS < (170 * LOG(RESD) IF DENS < (176 * LOG(RESD) https://spec2000.net/11-vshtoc.htm

+ 1670) THEN TOCd = 24 + 1695) THEN TOCd = 23 + 1720) THEN TOCd = 22 + 1745) THEN TOCd = 21 + 1770) THEN TOCd = 20 + 1795) THEN TOCd = 19 16/21

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IF DENS < (183 * LOG(RESD) + 1820) THEN TOCd = 18 IF DENS < (190 * LOG(RESD) + 1845) THEN TOCd = 17 Welcome To= 16 IF DENS < (197 * LOG(RESD) + 1870) THEN TOCd IF DENS < (211 * LOG(RESD) + 1895) THEN TOCd = 15 IF DENS < (218 * LOG(RESD) + 1920) THEN TOCd = 14 IF DENS < (225 * LOG(RESD) + 1945) THEN TOCd = 13 IF DENS < (232 + 1970) THEN TOCd = 12the Author Handbook Index* LOG(RESD) Petrophysical Training About Terms of Use Contact Us Search IF DENS < (239 * LOG(RESD) + 1995) THEN TOCd = 11 IS= (309 * LOG(RESD) + 2300) THEN TOCd = 0 Visual Analysis Of Logs For Wtocd = SF3 * TOCd / 100 + SO3 TOC Petrophysical Training Basic TOC Log Calculations Webinar Dates Log analysis TOC results should be calibrated to lab measured TOC from real rocks. ScaleDensity factors SF 2 and SF3 Kerogen Course and scale Dates offset SO2 and SO3 are determined by regression of lab versus log derived TOC values. Kerogen Volume If you want Order AV Courses TOC%, remove the "/ 100" from the final equations. Gas Content From TOC Order Video Courses TOC from Passey DlogR Order Reference Manuals Numerical Example: Method Become RESD An Associate DTC DENS Using spreadsheet from Downloads page TOC from Issler Crossplot Instructor 25 English 100 2.35 Method Metric 25 328 2350 TOC Spreadsheet Examples Petrophysical Consulting TOC from Spectral GR Method TOCs (RESD-DTC crossplot) = 0.11 weight fraction TOC from ECS Method Consulting Services TOCd (RESD-DENS crossplot) = 0.10 weight fraction TOC Log Analysis Examples Client List

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Total Organic Carbon TOC "META/TOC" SPREADSHEET -- TOC ASSAY FROM LOG ANALYSIS Coal Analysis This spreadsheet calculates Total Organic CVarbon (TOC) from the two different models described above. Coal Bed Methane Analysis Shale Gas Analysis "META/TOC" Total Organic Carbon Spreadsheet. Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis


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Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Shale Gas Analysis Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis Sample output from "META/TOC" spreadsheet for analysis of Total Organic Carbon from well logs. "META/TOC" Total Organic Carbon Spreadsheet.

TOC FROM SPECTRAL GAMMA RAY LOGS The uranium content of many kerogen bearing source and reservoir rocks is often a function of the kerogen content. Bob Everett suggests the following relationship: 1: TOCuran = SFuran * log(URAN / 4) Where: TOC uran = total organic carbon from uranium curve on spectral GR loh (fractional) URAN = uranium content (ppm) SFuran = scale factor = 0.05 default (range 0.02 to 0.08) Calibrate SFuran using lab derived TOC data. Note that the spectral GR could be a core GR log.

TOC FROM ELEMENTAL CAPTURE SPECTROSCOPY (ECS) LOGS The ECS log measures the weight contribution of various elements in the f ormation, for example calcium, oxygen, iron, silicon, and so forth. By using a least squares statistical approach, the elements can be composed into the minerals that mi ght be present in the rocks. One of the minerals can be kerogen. Results https://spec2000.net/11-vshtoc.htm

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are in weight fraction so kerogen can be compared directly to geochemical assays from the lab. The TOC and XRD or XRF lab data can be used to constrain the inversions, giving results that will naturally match kerogen To at the end pf this web page. and mineralogy data quite well. AnWelcome example is shown

TOC LOG ANALYSIS EXAMPLES Handbook Index


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Total Organic Carbon TOC Coal Analysis TOC calculated from Passey DlogR Method. There are numerous published Coal examples with much worse Bed Methane Analysis correlations between calculated and measured TOC, usually attributed to varyingShale proportions of Type I, II, and III Gas Analysis kerogen or mineral variations (calcite, dolomite, pyrite, and quartz) in the shale. Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis


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Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Shale Gas Analysis Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis The figure above shows a comparison of the DlogR method with the Issler model. Both methods use sonic and resistivity logs to calculate the depth variation in TOC. Red dots represent measured TOC analyzed on core samples using a Rock-Eval 2 instrument; blue dots represent re-analyses of the same samples using a Rock- Eval 6 instrument. For the Issler model, results are presented for both empirical (blue) and Archie (green) resistivity porosity methods. The DlogR method gives poor results for this well when observed thermal maturity is used (LOM = 5.0) An LOM value of 6.9 provides a good fit to the data but it is not representative of the true maturity.


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Total Organic Carbon TOC Coal Analysis Coal Bed Methane Analysis Shale Gas Analysis Immature Oil Shale Analysis Tight Gas Analyzis Tight Oil / Shale Oil Analyzis A nuclear magnetic effective porosity curves (light grey on porosity track) shows a close match to shale and kerogen corrected density-neutron effective porosity (left edge of red shading). Dark shading on porosity track is kerogen volume. NMR porosity, and corrected effective porosity match very well. The NMR effective porosity is unaffected by kerogen and clay bound water. The far right hand track is the mineralogy from an Elemental Capture Spectroscopy (ECS) log in weight fraction (excludes porosity but includes TOC). TOC from cores, Issler method, and ECS are in the track to the left of the porosity. They also match quite well. The ECS inversion was also calibrated to TOC and XRD data to get a match as good as this. Clay volume in second track from the right is from thorium curve calibrated to XRD total clay, with clay volume from ECS superimposed to show the close agreement. Everything makes sense when you CALIBRATE to lab data but may be NONSENSE if you don't gather the right data. Page Views 279 Since 01 Jan 2015 Copyright 1978 - 2017 E. R. Crain, P.Eng. All Rights Reserved


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