勘探开发介绍-英语.ppt

Exploring and Drilling for Oil and Gas,Prepared by Tom Sheeran,What are Oil and Gas?,Oil and Gas are substances found within the earths crust. They are thought to come from decomposed plant and animal matter. Scientists believe the plants and animals died long ago, and were slowly buried by thick layers of sediments. Over a long period of time, and with pressure and temperature, the organic materials were converted into the oil and gas which are found today. (For example, we know that present day garbage dumps give off methane gas),Prepared by Tom Sheeran,Oil in its natural state can be thick or thin, black or light colored. When oil is refined, many products can be obtained: Energy for power Gasoline for cars Diesel fuel for trucks and trains Hi-octane fuels for planes Heating oil for houses,Many other materials also come from petroleum: Plastics Materials for clothes (example: polyester fabrics) Chemicals for everyday use Paints,What else do we know about oil and gas?,Prepared by Tom Sheeran,Did you know that oil has natural gas in it?,The natural gas is in solution, just like the carbon dioxide which is put inside of pop to give it its fizz.,When oil is produced, some gas is produced with the oil.,A barrel of oil may contain anywhere from 1 cubic ft of gas, to over 10,000 cubic ft, depending on the type of reservoir.,Thats enough gas in a single barrel of oil to fill your whole house!,Prepared by Tom Sheeran,Where can we find Oil and Gas?,Prepared by Tom Sheeran,Some people think that oil is in big pools underground. Actually, most oil is trapped in the tiny pore spaces between grains of rock or sand. Most of these pores are too small to be seen with the naked eye.,Prepared by Tom Sheeran,So, how do we find oil-bearing rocks?,Oil and gas are found in natural traps within the earth. These traps consist of domes or faults. Impermeable rock above the trap prevents the oil and gas from migrating up to surface. An “impermeable” rock is one that fluid cannot pass through. without traps, the oil and gas could migrate all the way to the surface and evaporate.,Prepared by Tom Sheeran,Oil,Heres an example of a dome-shaped Oil reservoir.,Note the layer of impermeable rock which prevents the oil from migrating upwards. Also, note the layer of water below which prevents the oil from escaping down. Why?,Prepared by Tom Sheeran,Gas,Heres an example of a Gas reservoir.,Again, note the impermeable layer of rock preventing the gas from escaping.,Prepared by Tom Sheeran,Gas,Heres an example of an Oil reservoir with a Gas cap,Oil,Why do you suppose the gas is on top?,Prepared by Tom Sheeran,How do we find the oil reservoirs?,Geophysicists find reservoirs by bouncing sound waves off them, and timing how long it takes for the sound to come back Computers process the data to construct pictures of what the earth looks like underground.,source,receivers,t = 1 sec,t = 1.2 sec,t = 1.42 sec,Prepared by Tom Sheeran,What do we do after we find a reservoir?,?,?,?,Prepared by Tom Sheeran,We Drill Into It ! ! !,Prepared by Tom Sheeran,What do we drill with ?,Prepared by Tom Sheeran,A Drilling Rig !,Here are a few different types of drilling rigs available:,Drill ships and semi-submersible rigs are for drilling in water depths from 100 to 5000+ ft.,Jackup Rig,For drilling in water depths from 15 ft to +/- 350 ft.,Inland Barge,For drilling in water depths from 8 to 30 ft.,Prepared by Tom Sheeran,Whats a drilling rig ?,Prepared by Tom Sheeran,A Drilling Rig is: A package of special equipment put together to enable us to drill into the earth. A drilling rig has many different parts: a derrick, a substructure, hoisting equipment, engines for power, drill pipe, steel tanks, pumps, solids control equipment, and many other pieces. Did you know that some drilling rigs can drill as deep as 6 miles? Thats as deep as Mt. Everest is tall!,Prepared by Tom Sheeran,Drill string Drill bit,The hoisting equipment consists of: a crown block, a traveling block, drilling line, and a drawworks to pull the drilling line up or down.,substructure,This picture shows the hoisting equipment on a rig. This equipment is used to raise or lower the drillstring, which is picked up in 30 foot long segments, or “joints”, of drill pipe.,spare drill pipe,This shows a 30 foot section of drill pipe being added to the drill pipe already in the hole.,Prepared by Tom Sheeran,Heres a picture of the drill bit drilling the rock.,The drill string is turned at surface, which turns the bit at the bottom of the hole. The teeth on the drill bit grind the rock into fragments, or “cuttings”.,Drilling mud is pumped down the inside of the drill pipe, through jet nozzles in the bit, and into the “annulus”. This is the space between the sides of the hole and the drill pipe. The mud lifts the cuttings and circulates them back to surface where they are removed.,Prepared by Tom Sheeran,3) the mixture of drilling mud and drill cuttings are circulated up the annulus,screens,5) the drill cuttings are removed, and form a cuttings pile. This can be hauled off and disposed of.,4) the mixture is circulated across screens at surface,1) Clean drilling mud is taken from the steel mud tanks and pumped down the inside of the drill pipe.,2) the mud is circulated through the drill bit into the annulus, lifting the cuttings removed by the drill bit.,6) Clean mud falls through the screens and is returned to the pits,The Drilling Mud Cycle,mud pump,Prepared by Tom Sheeran,Heres a sequence showing how holes are drilled,First, a large drill bit is used to drill a short interval of hole.,Then, steel casing is run and cemented on the outside to keep the hole from collapsing.,0,200,Prepared by Tom Sheeran,Next, a smaller bit is run inside the first casing. This bit drills out the bottom of the casing, and drills new hole.,Then, this new hole is also cased off and cemented.,Prepared by Tom Sheeran,Again, a smaller hole is drilled out,and smaller casing is run to keep the hole from falling in.,Prepared by Tom Sheeran,In this way, the hole is drilled in stages, until the target reservoir rock is penetrated. At this point, the geologists must figure out if there is oil or gas in it.,Prepared by Tom Sheeran,They do this by running logs across the zone. Logs are tools run on electric cable (“wireline”) which record the physical properties in the rock such as resistivity, porosity, density, radioactivity, and pore pressure.,How do Geologists tell if the reservoir has oil or gas?,Prepared by Tom Sheeran,Sand,Shale,Siltstone,Shale,Siltstone,Dolomite,Shale,Heres an example of what a log looks like. Geologists look at logs to decide whether or not to complete a well (if there is oil), or abandon it (if theres no oil).,Prepared by Tom Sheeran,Can you tell where the geologist would complete this well?,Gamma Radiation,200 500 3000,Electrical Resistivity,Porosity,Looks like good sand quality,good resistivity, may have oil or gas,poor resistivity, probably water,good porosity,poor porosity,good porosity,poor resistivity, probably water,poor porosity,good porosity,Right here! This shows a clean sand, with good porosity and resistivity.,good porosity,poor porosity,Prepared by Tom Sheeran,If the well looks good on the logs, we run a final string of casing across the production zone, and cement it in place.,Prepared by Tom Sheeran,Then, we run perforating guns in the hole and perforate (shoot holes ) in the casing across the productive zone.,Prepared by Tom Sheeran,Production tubing is run, with a packer to isolate the produced zone from the casing above.,tubing,Packer,Prepared by Tom Sheeran,Finally, the well is produced into a pipeline, which takes it to production facilities on surface.,Prepared by Tom Sheeran,The production facilities on surface separate out the gas, oil, and water into their separate phases.,Prepared by Tom Sheeran,Production Separator,Oil,Produced Water,Produced Gas,From there, the oil and gas may be refined further before being ready to market.,Oil Refinery,Storage Tanks,Prepared by Tom Sheeran,Finally, the gas and oil can be sold to power cars and heat houses.,Prepared by Tom Sheeran,And Thats Where Oil and Gas Co