The facts about Petroleum
How was petroleum formed?
Just how petroleum was formed is still something of a mystery. Petroleum – both liquid oil and natural gas – does not contain any obvious clues that tell us about its origins. In contrast, we can follow the development of coal because we can find traces of prehistoric plant life in coal fragments at all stages of their formation.
All petroleum products are “complete” products and each one is fully developed in the earth and different from all the others. Some petroleum is thick and waxy and it could be used as axle grease without any changes. But some petroleum is so light that it could be used to fuel a diesel engine.
Some scientists, known as petroleum geologists, have developed a theory about the formation of this important energy source. The theory states that petroleum was formed from decayed organic material, both animal and vegetable, that lived close by – or within - the ocean. The dead material was built up on the ocean floor. Then certain chemical alteration processes turned the dead material (debris) into fatty and waxy substances.
Over time, the buried substances - dead marine animals and plants – became petroleum. It is estimated that this process (the conversion of decayed organic material into petroleum) took up to 10 million years. The creation of petroleum occurred sometime between 200 and 400 million years ago. Now. The question we ask, if the creation of Petroleum it takes us to 400 million years, then how old exactly our country? No one could tell the exact age of our beloved island existed.
Another, but less-accepted theory, is that volatile fluids have “cooked out” from the earth’s rock mantle when the planet was forming. The fluids work their way to the upper layers of the earth's crust. Petroleum is formed in rocks that are fine-grained and soft. There are great forces of water and pressure acting on these porous rocks. This pressure eventually forced the petroleum from the pores and cracks of the rocks.
The petroleum was gradually “squeezed” into the water’s depths and it continued to rise until it reached a barrier known as a “seal”. The petroleum then moved along the barrier until it reached the highest point, known as a “trap”. Then it could go no further. It began to accumulate as more and more was squeezed out of the porous rock. This movement or “migration”, so long and so slow, often means that petroleum is discovered far away from the place where it was formed, and in a great variety of rocks. Often, it is found in large amounts in places where rocks have been forced by earth movements into the form of a dome. Petroleum rises into the dome and it is trapped there. The rocks that capture the petroleum are called reservoir rocks.
A typical petroleum deposit is made up of three layers:
1. There is a zone where the pores of the rocks are filled with natural gas.
2. Underneath the gas is a zone where the rocks have their interstices (or pores) full of oil. This oil also contains dissolved gas, as the gas is under great pressure (Similar to bottled gas, propane and butane gases which are liquids through pressure.)
3.Beneath the oil is water.
Dear readers, Now the next step is that knowing who finds the Petroleum, and where? the following passage is gonna be very interesting one, as it is essential what we should know for the sake of the general knowledge.
Who finds petroleum and where?
Finding petroleum was once a job for prospectors who dug wells in places that they thought would be suitable - perhaps a line of hills or a swamp. So they drilled a hole there and it was known as a “wild-cat” well. But the demand for petroleum became too great to rely on guesswork. Wildcat prospectors had to give way to specialist scientists. These scientists are geologists and geophysicists.
Geologists study rocks and soils in the layers of the earth’s crust. Many geologists are specialists. Some are interested in sedimentary rocks. These are called sedimentologists. Others study fossils. They are palaeontologists.
Others specialise in the chemistry of rocks and the fluids they contain. These are geochemists. They work closely with geophysicists in the search for petroleum. Geophysicists study and measure the physical phenomena of the earth. They measure temperature, magnetism, earth movements, water flow, assess earthquakes. Their measurements are used for three purposes:
1. First, to improve our knowledge and understanding of the earth (what it is and what makes it tick).
2. Second, to find out what is the nature of the earth for the construction of tunnels, buildings, power stations and other structures.
3. And third, to explore the earth for petroleum, natural gas and minerals, and to establish whether these are suitable for commercial exploitation.
To make their measurements, they “read” gravity, electricity, light, shock waves, sound, heat and radioactivity. They put their instruments on the surface, underground, in water, in the air - or all four. They also produce vibrations in the earth using vibrating machines or compressed air “guns” in the ocean. Recordings of the transmitted and reflected vibrations will “tell” them what sort of rocks there are. These are called seismic surveys. (“Seismology” is the study of earthquakes.
The Geophysicists can tell petroleum explorers where these large areas of sedimentary rocks (sedimentary basins) are located. They do this by measuring the gravitational force and the earth’s magnetic field at the earth’s surface. Areas of lower magnetic field strength and lower gravitational force are areas underlain by sedimentary rocks. There are a number of Australian sedimentary basins.
There are two seismic methods to detect sedimentary rocks: reflection and refraction. In both methods, shock waves pass through the rock structure and are recorded on a device called a geophone. When their underground maps are ready, geophysicists hand them over to petroleum engineers, because the only sure way to tell if the petroleum is actually there is to drill. Tests wells are drilled, to bring up samples of rock. These are studied for evidence of petroleum.
Petroleum geophysicists look for sediments. But they know that petroleum often has migrated from the place where it was formed. So they look for the non-porous rocks that have “trapped” petroleum. When oil exploration wells are drilled, a range of “down hole” measurement tools can detect more information from the well, such as rock density, radioactivity, magnetic strength and porosity. Geophysicists can “read” the differences because their instruments “behave” in different ways for each. Similarly, differences between coal, water and petroleum can be detected. So geophysicists look for “contrasts” and these differences tell them about ore bodies and reefs; or ancient earth movements; or strange rocks that earthquakes have shoved into other rocks.
If petroleum is there, how much? Can it be recovered? How much can be recovered? If oil or gas is produced from a well, its pressure and flow rates are accurately measured. Most of the wells that are sunk are dry. Either no petroleum or gas is found, or the amount is so small it is not worth getting out. The search never stops!
Monday, November 24, 2008
East Timor finds evidence to resist Woodside gas plan
By Lindsay Murdoch
Dili November 24, 2008
A HIGH-STAKES battle taking place between East Timor and Woodside Petroleum over the Greater Sunrise oil and gas field is set to escalate after a US company's survey of 45,000 square kilometres of the Timor Sea.
The president of Houston-based DeepGulf, Mark Mozkowski, says the survey will provide evidence to back East Timor's demand that Woodside build a liquefied natural gas plant on the half-island country.
"At the moment it looks pretty feasible," Mr Mozkowski said, referring to a pipeline from the field to East Timor.
Woodside has ruled out building a pipeline, partly because of a 3400-metre deep gash in the ocean floor, known as the Timor Trough.
But Mr Mozkowski said his company's survey shows the trough's walls are not as steep as previously thought.
"There isn't much of a slope at all, contrary to what other people say," Mr Mozkowski told The Age in the East Timorese capital Dili.
He said the only data previously made public about the trough was "soft and sloppy" material obtained from satellite images.
DeepGulf has had three survey boats operating in the waters off East Timor since June. Mr Mozkowski said the survey would be completed by January and then a report prepared on the results.
DeepGulf was commissioned to do the survey for the East Timorese Government and a consortium of South Korean companies.
East Timor's leaders have recently hardened their rhetoric over their demand for the plant on its shores, even threatening to block the $14 billion project rather than yield to Woodside's terms.
The country's President, Jose Ramos Horta, told the Northern Territory Parliament this month that he "would prefer to forgo Greater Sunrise than surrender to the dictates of a bunch of oil executive millionaires".
Woodside this year declared it was considering only two options for Greater Sunrise, which contains about 300 million barrels of light oil and 8.3 trillion cubic feet of natural gas — piping and processing the gas in Darwin where ConocoPhillips, one of Woodside's partners in the venture already, has a processing plant; or building a floating plant in the Timor Sea.
Tensions over the field rose when East Timor recently signed a memorandum of understanding that gives South Korea preferential access to the gas, the first time East Timor has made a gas supply contract with a foreign country since it became independent in 2002. But under the Greater Sunrise agreements, Woodside and its partners retain the right to market the gas.
A spokesman for Woodside said the company will "progress the concept which develops the Greater Sunrise reservoir to the best commercial advantage, consistent with good oilfield practice".
Under the agreements, East Timor will receive 50 per cent of government upstream revenues generated from Greater Sunrise.
"This provides a long-term, stable and significant cash flow to Timor-Leste (East Timor)," the spokesman said.
Jose Teixeira, a former minister who played a key role in the Greater Sunrise negotiations, told The Age that the benefits for East Timor were too great for the field not to proceed.
Unless a development plan is in place by 2013, the deal can lapse.
Mr Ramos Horta told the NT Parliament that his country would soon appoint a senior negotiator for Sunrise: "We are ready to study and analyse all options, to talk and explore ideas and arrangements that are mutually beneficial."
But he also signalled East Timor was ready to continue to resist Woodside. "My people are poor and have been victimised for too long. You are rich and powerful. So I have to side with my country and people who are weaker and poorer."
http://www.woodside.com.au
Dili November 24, 2008
A HIGH-STAKES battle taking place between East Timor and Woodside Petroleum over the Greater Sunrise oil and gas field is set to escalate after a US company's survey of 45,000 square kilometres of the Timor Sea.
The president of Houston-based DeepGulf, Mark Mozkowski, says the survey will provide evidence to back East Timor's demand that Woodside build a liquefied natural gas plant on the half-island country.
"At the moment it looks pretty feasible," Mr Mozkowski said, referring to a pipeline from the field to East Timor.
Woodside has ruled out building a pipeline, partly because of a 3400-metre deep gash in the ocean floor, known as the Timor Trough.
But Mr Mozkowski said his company's survey shows the trough's walls are not as steep as previously thought.
"There isn't much of a slope at all, contrary to what other people say," Mr Mozkowski told The Age in the East Timorese capital Dili.
He said the only data previously made public about the trough was "soft and sloppy" material obtained from satellite images.
DeepGulf has had three survey boats operating in the waters off East Timor since June. Mr Mozkowski said the survey would be completed by January and then a report prepared on the results.
DeepGulf was commissioned to do the survey for the East Timorese Government and a consortium of South Korean companies.
East Timor's leaders have recently hardened their rhetoric over their demand for the plant on its shores, even threatening to block the $14 billion project rather than yield to Woodside's terms.
The country's President, Jose Ramos Horta, told the Northern Territory Parliament this month that he "would prefer to forgo Greater Sunrise than surrender to the dictates of a bunch of oil executive millionaires".
Woodside this year declared it was considering only two options for Greater Sunrise, which contains about 300 million barrels of light oil and 8.3 trillion cubic feet of natural gas — piping and processing the gas in Darwin where ConocoPhillips, one of Woodside's partners in the venture already, has a processing plant; or building a floating plant in the Timor Sea.
Tensions over the field rose when East Timor recently signed a memorandum of understanding that gives South Korea preferential access to the gas, the first time East Timor has made a gas supply contract with a foreign country since it became independent in 2002. But under the Greater Sunrise agreements, Woodside and its partners retain the right to market the gas.
A spokesman for Woodside said the company will "progress the concept which develops the Greater Sunrise reservoir to the best commercial advantage, consistent with good oilfield practice".
Under the agreements, East Timor will receive 50 per cent of government upstream revenues generated from Greater Sunrise.
"This provides a long-term, stable and significant cash flow to Timor-Leste (East Timor)," the spokesman said.
Jose Teixeira, a former minister who played a key role in the Greater Sunrise negotiations, told The Age that the benefits for East Timor were too great for the field not to proceed.
Unless a development plan is in place by 2013, the deal can lapse.
Mr Ramos Horta told the NT Parliament that his country would soon appoint a senior negotiator for Sunrise: "We are ready to study and analyse all options, to talk and explore ideas and arrangements that are mutually beneficial."
But he also signalled East Timor was ready to continue to resist Woodside. "My people are poor and have been victimised for too long. You are rich and powerful. So I have to side with my country and people who are weaker and poorer."
http://www.woodside.com.au
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