Outline for OilOutline for Oil 1. What is oil and how is it formed?- Oil comes from ORGANIC MATTER (marine plant material – PHYTOPLANKTON)- Complex mixture of liquid HYDROCARBONS- Natural Gas (also HYDROCARBONS – mostly METHANE) also usually present- Product of post-depositional processing by elevated TEMPERATURE and PRESSURE as the sediments containing the organic matter is buried deeper inthe Earth.- 3 processes – depth relateda. DIAGENESIS: 0-100s m, T < 50 C, minerals dissolved and depositedby percolating groundwater. Biogenic activity - > BIOGENIC GASb. CATAGENESIS: z 3.5 km, T: 50-150 C, Pressure  1500 bars. Compaction and loss of water. Biological activity decreases. THERMOGENIC gas generation -> “wet” gas (contains condensed hydrocarbon gases), Organic material -> KEROGEN -> PETROLEUM. This depth range constitutes the “Oil Window”c. METAGENESIS: z > 3.5 km, T > 150 C, Pressure  1500 bars. Metamorphism begins, lose PETROLEUM, produce only “dry” gas.2. Economic Deposits- To be economic, requires concentration- Oil “Trap” must have:- SOURCE ROCK (where the OM comes from) - RESERVOIR ROCK – porous, permeable rock through the oil can move (migrate) and collect.- CAP ROCK – impermeable barrier preventing loss of oil and gasat Earth’s surface (Oil and gas will tend to rise in the Earth due totheir low density – relative to the pore water in the rocks)- 2 types of oil trap- STRUCTURAL e.g. Anticlines, Faults, Unconformities- STRATIGRAPHIC e.g. Reefs, Lateral lithological changes3. Origin of the modern oil industry- Edward L Drake 1859- Pennsylvania Rock Oil Co., Titusville PA – Oil Creek- Processed for KEROSENE – alternative lamp fuel (normally whale oil)- Production from 69 ft, 10-35 barrels/day4. Exploration process- Teams of geologists, geophysicists and engineers- Identify basins - > structures- Continually refine interpretation to maximize production5. Drilling Technology- Early wells drilled with simple rotating pipes equipped with serrated edges- Cable-Tool drills – popular in early 20th century. Pound heavy bar on floor of well. Periodically flush out cuttings. Good to ~1000 m- Rotary Drills – drill equipped with rotating diamond studded teeth. Drilling mud pumped down interior of drill pipe flushes cuttings back to the surface and stabilizes the borehole.- Directional drilling – maximize production and help access subsurface targets.6. Methods to stimulate flow- Production determined by reservoir POROSITY (how much pore space there is) and PERMEABILITY (how connected the pores are)- These can be enhanced by:- Acid treatments- Hydro fracturing- Perforating guns7. Recovery Phases- Primary – free flowing oil driven by “reservoir pressures”- Water Drive- Gas Cap Expansion- Solution Gas (“Coke” e.g.)- Typically produces only ~20-30% oil in place- Secondary – ENHANCED OIL RECOVERY- Water injection (increase pressure)- Gas re-injection (increase pressure)- Steam flooding (reduce viscosity of oil)- Fire flooding (reduce viscosity of oil)- Chemical flooding (reduce surface tension)- Expensive – increases production to 50-60%- Tertiary phase – OIL MINING8. Petroleum refining- Separate and refine hydrocarbons from crude oil- PRIMARY STAGE – FRACTIONATION/DISTILLATION- Based upon varying condensation temperatures. Lighter (shorter chain) hydrocarbons condense at lower temps i.e. Higher on refinery tower.- Early refineries based on fractionation, produced mostly KEROSENE, HEATING OIL and lubricants. GASOLINE too dangerous!- Modern refineries – add 2nd stage, CRACKING, to maximize production of desirable fractions.- CRACKING = chemical splitting of long h/c chains to shorter ones.- THERMAL CRACKING- CATALYTIC CRACKING – synthetic zeolite acts as CATALYST (speeds and facilitates reaction but does not contribute to reaction). Also adds HYDROGEN – HYDROGENATION – boost gasoline yield.- Modern split: 50% GASOLINE, 30% FUEL OIL, 7.5% KEROSENE- Contaminants include SULPHUR, VANADIUM, NICKEL – add value to process.9. Oil distribution – where is it, how much is there?- ~100 yr. exploration and production -> picture of where future oil is coming from.- ~600 sedimentary provinces – most tested to some degree- ~65% oil in place is in Middle East- Consuming at much faster rate than new oil is forming – will run out.- M.KING HUBERT (USGS) analyzed production and consumption in 1948 – predicted production would peak in late 1990s. Subsequent productmatched his prediction – UNTIL Arab oil embargo (-> restricted production and fuel conservation). Resulted in extended life span. - Production predicted to peak and start to decline ~2020- Rising cost will stimulate interest in old fields and fields previously thought to be uneconomic.- New technology and new geologic models (e.g. Sub-salt production in the deepwater Gulf of Mexico) will help develop “new” reserves.- ANWR – potential large field in Alaska (east of Prudhoe Bay)- Optimistic predictions ~16.5 billion barrels (bbo) in place. More realistic numbers suggest there may only be ~3.2 bbo (~6 months US consumption!)- If permission given today – first oil would not begin to flow for at least 10 years, peaking at ~300,000 barrels/day around 2020.- Alternative to ANWR – raise SUV mileage standards (considered to be a light truck at the moment). Raising standard to that currently required forcars would a) Save ~10% oil imported, b) reduce CO2 emissions by 200 million tons( CO2 is #1 green house gas responsible for global