Introduction to Petroleum Geochemistry and its Significance in Hydrocarbon Exploration and How to Get Your Scholarships Abroad? Oleh: RAGIL PRATIWI GEOSERVICES UNDIP SHARING SESSION Semarang, 20 th June 2015
1st 2nd Course Outline Introduction to Petroleum Geochemistry How to Get Your Scholarships Abroad?
Course Outline Introduction Theories on Origin of Petroleum Petroleum Geochemistry: Introduction Organic Matters in Source Rocks Source Maturation and Petroleum Generation Geochemical Laboratory Analysis Introducing Biomarkers
Recommended References Waples, D.,W., 1985, Geochemistry in Petroleum Exploration, International Human Resources Development Corporation, Boston. Hunt, J.M., 1996, Petroleum Geochemistry and Geology, W.H. Freeman and Company, 2nd ed., San Francisco. Peters, K.E. and Moldowan, 1993, Biomarker Guide Interpreting Molecular Fossils in Petroleum and Ancient Sediments, Prentice-Hall, Inc., Englewood Cliffs. Peters, K.E., Walters, C.C., Moldowan, J.M., 2005, The Biomarker Guide, Vol. 1: Biomarkers and Isotopes in the Environment and Human History, 2nd ed., Cambridge University Press, Cambridge. Peters, K.E., Walters, C.C., Moldowan, J.M., 2005, The Biomarker Guide, Vol.2: Biomarkers and Isotopes in Petroleum Exploration and Earth History, 2nd ed., Cambridge University Press, Cambridge. Articles on Biomarkers in AAPG (American Assoc. of Petroleum Geologists) Bulletin, Organic Geochemistry Papers on Biomarkers in IPA (Indonesian Petroleum Assoc.) Proceedings
Theories on Origin of Petroleum Abiogenic Petroleum was formed from deep carbon deposits, perhaps relating to the formation of the Earth, and that petroleum migrate upward from the mantle (Thomas Gold, 1999) Biogenic Pooled oil and gas in porous reservoirs can only be explained by its origin in thermally mature, organic-rich, sedimentary source rocks (Wallace Dow, 2002) Satyana (2014)
Petroleum Geochemistry Geochemistry is the application of chemistry to the study of rocks and fluids. (Selley, 1985 : Elements of petroleum geology) The application of chemical principles to the study of the origin, migration, accumulation, and alteration of petroleum and the use of this knowledge in the exploration and production of oil and gas. (Hunt, 1996 : Petroleum geochemistry and geology) Satyana (2014)
What can petroleum geochemistry do? evaluate physical and chemical properties of oil and/or gas in basin determine how many oil and/or gas families are present in basin expect source/s of oil and/or gas in basin evaluate presence, quality, and maturity of source rocks in basin determine volumetric of oil and/or gas generated, migrated, and accumulated in basin, evaluate migration pathways of oil and/or gas in basin predict fluid type (oil/gas/water) containing in prospect ahead of drilling predict in-reservoir alteration (e.g. biodegradation) and its trend understand intra-field/-reservoir petroleum variations etc. Satyana (2014)
What can petroleum geochemistry do? Clayton and Fleet (1991) in Satyana (2014)
How we have ignored petroleum geochemistry? a. What people know (in lesser detail): reservoir, trap, seal, kitchen, migration. b. Too much evaluation on reservoir and trap. Too less evaluation on hydrocarbon charging (evaluation on kitchen and migration are too over-simplified). c. One with strong interest, knowledge, and experience on geochemistry is scarce. Satyana (2014)
Trilogy of Exploration Success Needs integration of Geology, Geophysics, and Geochemistry 3G and always see them historically Satyana (2014)
After Murris (1984) in Satyana (2014)
Source Rock Sedimentary rocks that are, or may become, or have been able to generate petroleum are source rocks Tissot and Welte (1984) Sedimentary rocks commonly contain minerals and organic matter with the pore space occupied by water, bitumen, oil, and / or gas Peters and Cassa (1994)
Petroleum, Hydrocarbon and Non Hydrocarbon Petroleum is a complex mixture of gas, liquid, and solid hydrocarbons and nonhydrocarbons occurring naturally in the earth Hydrocarbon is commonly used in the petroleum industry to indicate crude oil or natural gas. In the chemical sense, hydrocarbons are compounds containing only carbon and hydrogen. Nonhydrocarbons contain elements in addition to hydrogen and carbon. For example, NSO compounds contain nitrogen, sulfur, or oxygen, and porphyrins contain metals such as vanadium or nickel. Peters and Cassa (1994)
Bitumen Brooks (1987) in Satyana (2014)
Fraksi Bitumen dan Crude Oils Waples (1985)
Kerogen Kerogen (from kerosene generator) is defined as the organic component of source rocks that is insoluble in common organic solvents and aqueous alkali (NaOH solution). It is the parent of petroleum. The soluble portion of the organic matter is termed bitumen or total soluble extract (TSE) Kerogen is of complex biological origin; it is derived from dead organisms whose organic remains survive the early stages of diagenesis and lithification. Satyana (2014)
After Clayton and Fleet (1991)
Source Rock Screening
Source Rock Screening
Rock Eval - Pyrolysis Time
TOC & Rock Eval - Pyrolysis TOC (Total Organic Carbon) : a measurement the organic richness of sedimentary rocks S1 : the amount of free hydrocarbon S2 : the amount of the remaining hydrocarbon potential S3 : the amount of carbon dioxide released during pyrolysis Hydrogen Index (HI) : the hydrogen richness = S2/TOC x 100% Oxygen Index (OI) : the oxygen richness = S3/TOC x 100% Miles (1989)
Tmax Rock Eval - Pyrolysis represents the temperature at which the maximum amount of hydrocarbons degraded from kerogen are generated The Production Index (PI) is also in part indicative of the degree of thermal maturity (Peters, 1986) PI = S1 / (S1+S2) PI < 0.4 = immature PI : between 0.4 and 1.0 = mature PI > 1.0 are indicative of overmature Miles (1989)
Ibrahimbas and Riediger (2004)
Quantity, or amount of organic matter Quality, or type of organic matter Peters and Cassa (1994)
Exercises 1 From data above, can you please explain : 1. Which section that could be source rocks? 2. What kind of fluids that have been generated? 3. How mature is that rock?
Tipe III immature source rocks Ibrahimbas and Riediger (2004)
The Application of Rock Eval Pyrolysis for Kerogen Type Analysis Peters and Cassa (1986)
REP Application
REP Application
Source Maturation and Petroleum Generation Mahmoud, et all (2006) in in Satyana (2014)
Source Maturation and Petroleum Generation
Merrill (1991) in Satyana (2014)
Source Maturity Analysis The most common methods to understand the maturity of source rocks are : 1. Vitrinite reflectance 2. Spore color index THERMAL MATURITY IMMATURE MATURE MAIN PHASE OF LIQUID PETROLEUM GENERATION & PRESERVATION DRY GAS OR BARREN SPORE COLOUR POLLEN / SPORE COLOUR "STANDARD" MUNSELL COLOUR STANDARDS (MATTE FINISH) SCI Collins 1990 (1-10) Colourless (1) Colourlesspale yellow (2) Pale yellow (3) Lemon yellow (4) Golden yellow (5) Orange (6) Orange brown (7) Brown (8) Dark brown (9) Dark brown black (10) % Ro. Vit. 0.20 0.25 0.33 0.40 0.51 0.65 0.77 0.85 1.00 1.30 1.70 2.40 3.00 APPROXIMATE CORRELATION TO OTHER SCALES Lemigas (1-5) 1997 2007 1 1+ 2-2 2+ 3-3 3+ 4-4 5 Thermal Alteration Index (TAI) 1 1+ 2-2 2+ 3-3 3+ 4-4 5 Staplin (1-5) 1 1.5 2 2.5 3 4 5 Batten (1-7) 1 1/2 2 2/3 3 3/4 4 4/5 5 5/6 6 7 HUE 7.5y 7.5y 7.5y 5y 2.5y 10y,r 10y,r 10y,r 10y,r 10y,r VALUE 9 9 9 8 8 6 5 4 3 2.5 CHROMA 4 8 10 12 12 10 6 DOMINANT WAVE LENGTH (µm) 31 57.5 68.5 82.5 80.5 68.5 61 50 30 16 MUNSELL PROD. NO. 14,479 14,481 12,992 13,618 14,253 12,424 12,382 17,209 15,814A 15,978 Compiled from Collins 1990, and LEMIGAS versions of Munsell colour standards chart, 1997, 2008 Batten (1981) mod. by Geoservices Colours are based on the Munsell colour solid (right), where each colour is described by a hue, value and chroma such as 5R 6/4. Hue is assigned a letter and divided into ten segments, 5 being the middle of a hue and 10 the boundary between one hue and the next. Value represents the shade of a colour from 1 (light) to 10 (dark) and chroma is the degree of saturation, from grey to vivid. PURPLE r,p p RED PURPLE BLUE r p.b Dimensions of the colour solid WHITE BRIGHTNESS YELLOW-RED y,r b HUE BLUE BLACK y YELLOW g.y CHROMA (SATURATION) g b,g BLUE-GREEN RED- PURPLE GREEN- YELLOW GREEN Purple section of the colour solid vivid purple brilliant purple vivid purple very light purple brilliant purple strong purple deep purple very deep purple very light purple light purple moderate purple dark purple very dark purple very pale purple pale purple greyish purple dusky purple light purplish purplish grey white light grey white purplish grey grey dark purplish grey dark grey very dusky purple purplish black black
Vitrinite Reflectance
Microscopic Analysis of Organic Remains
Spore Colour Index and Kerogen Typing palynology.geoscienceworld.org