This article is on WeChat public account ” Star Science Review “ reproduced with permission from the author: Yun Wu ghost town, design: Chen Rui Ting, Chen Jingyi, editor: Xie Yu Han, Zhang Nan. Planet Science Review, a brand of the Planet Institute, science, exploration, curiosity. Head image source: IC photo
March 2020 is destined to go down in history. On the one hand, the onslaught of new coronavirus pneumonia epidemic is spreading rapidly around the world, and on the other hand, giants who control more than 40% of the world ’s oil and gas production tear their faces. .
In the face of Russia, which insisted on no longer reducing output at the OPEC + meeting, Saudi Arabia is determined to increase its oil production capacity to seize the market, and the oil price war has started without warning. On Black Monday, March 9, world oil prices fell sharply, falling more than 30%.
The decline in industrial raw material prices is generally good news for the world economy, but the cost of oil and gas production in the United States is high, and the rapidly spreading new crown pneumonia epidemic has also made people less confident about future economic growth. Further shocks caused the US stock market to plunge on that day, with a drop of more than 7%, triggering a blowout, which broke the bubble of 11 consecutive years of rise in the US stock market since the 2008 subprime mortgage crisis.
The two recent international oil price fluctuation curves | WTI oil prices and Brent oil prices are the two most important crude oil price indexes, and this round of declines began on March 9 Started on Monday, and both reached their lowest point on March 18. Image source @ Oilprice.com
Then a chain reaction between oil prices and US stocks. On March 18, the price of WTI crude oil fell to as low as 20.37 US dollars a barrel. This is the lowest oil price since 2002 when it was the lowest of 18.02 US dollars / barrel. US stocks also occurred on March 9, 12, 16, and 18. Four fuses have aggravated the world’s concerns about the economic crisis.
Under the dual effects of new crown pneumonia and the oil price war, the world economy has turned a bloody and dark page. The oil giants on this planet are tearing off their final masks, and a war between the giants has broken out. How did all this come, and where will the wheel of history be taken? What does it mean for China’s future, and for ChinaWhat changes have people’s lives brought?
Who made the oil giants?
Oil and most natural gas are produced in strata formed by ancient oceans or lakes. A large number of organisms (mainly plankton) Gradually accumulate, and form rocks with the sediment. After undergoing high temperature and high pressure transformation, complex hydrocarbons are released. The heavy ones are oil and the light ones are gas. [2] . Oil and gas are formed from a wide range of source rocks. After undergoing a complex migration process underground, they are stored in formations with storage capacity and become today’s large or small oil and gas fields.
Simple schematic diagram of petroleum genesis | Organic genesis is still recognized by the international academic circle of petroleum genesis. At present, all countries in the world use this theory to guide petroleum production; inorganic genesis can only Explain the formation of some natural gas, and no petroleum of inorganic origin has been found. For details, please refer to reference [2, 24]. Picture source @WSGS | Wyoming State Lands Bureau [3], subject to change
Different regions of the world have experienced very different geological evolution histories, so countries also have completely different endowments of petroleum resources. It is easy to find oil in the strata formed by the ancient oceans. This phenomenon was discovered at the beginning of the last century and is called the “strong marine oil” theory.
Most of the countries with the highest reserves of contemporary petroleum resources have been covered by large-scale oceans in the last 200 million years, and oil and gas are mainly produced in the strata formed by ancient oceans. Take Saudi Arabia as an example. In the Jurassic, 190 million years ago, its land was located in the warm and shallow sea near the tropics, and it continued until the later Cretaceous. PhytoplanktonInterest, the fighting in the ocean is also non-stop, day and night, countless organic matter accumulated on the sea floor, bred a series of crude oil rocks, and eventually formed a rich oil [4] .
Ranking of world’s proven reserves of petroleum resources in 2018 | Because the proven reserves and output rankings of natural gas are very different from those of oil, they are not shown here, and the following also Take oil as an example. Cartography @ 陈睿 婷 | Planetary Science Review
In the late 1950s, Chinese oil workers discovered the Daqing Oilfield. The area was a large area of freshwater lakes during the Cretaceous period, and the bottom of the lake was rich in organic matter. Therefore, the discovery of this field was also It is regarded as a sign of the strong rise of the “land-phase oil” theory, which is the inheritance and development of the “sea-phase oil” theory.
The seawater exited from China earlier, and most of the oil and gas resources that have been discovered in China formed in the environment of onshore lakes. [2,5] Regardless of area, duration, biomass carried, or final oil and gas generation potential, onshore lakes cannot be compared with the ocean. This congenital deficiency is destined that China has not become an oil giant.
Contemporary oil prospectors have long ceased to confine their minds to the boundaries of land and sea. Instead, they have actively used all new ideas and new technologies to search for oil around the world, delaying the depletion of oil resources. The latest major breakthrough was an event called “Shale Gas Revolution” , which changed the world’s energy pattern and changed the face of the oil industry; it brought a wave to the entire planet Another wave of change has also directly led to an oil price war.
So, to understand the ins and outs of the recent oil price war, you first need to understand what the shale gas revolution is.
What is the shale gas revolution and whose life has been lost?
The shale gas revolution is a term commonly used in the media and industry. It is often used to describe the large-scale exploration and development of shale gas in the United States from around 2004. It has also been extended to mining methods similar to shale gas. Shale oil and tight oil and gas fields. Since 2012, a similar term “tight oil revolution” has also been common in media reports. In recent years, breakthroughs in the exploration and development of shale oil and tight oil and gas have been the main reasons for the large increase in U.S. oil reserves and production. [ 7-8] .
The map of oil production changes in the United States, Saudi Arabia, and Russia in recent years | In 2008, US oil production stopped falling and rose, becoming the largest dark horse in the world’s energy landscape . Cartography @ 陈睿 婷 | Planetary Science Review
The shale gas / tight oil revolution is not a scam among some people. It is a major subversion of the human oil industry, and it has changed people’s oil and gas exploration targets, oil and gas exploration technology, and oil and gas exploration ideas.
In the microscopic world, rocks are actually more like sponges, with more or less pores distributed inside, especially sedimentary rocks. (such as Sandstone, mudstone, limestone, etc.) contains more pores.
Quartz sandstone under an electron microscope. The field of view is 4 mm wide, and the large particles are quartz sand particles with some clay minerals attached to the surface. The black space is the pores between the sandstone particles. Tu Yuan @ EMGS (Central-Eastern Geological Association, a British non-governmental spontaneous geologist and enthusiast association, see emgs.org.uk)
Fluids such as oil, gas, and groundwater are distributed in the pores between the rock particles. The narrow channel connecting the pore space is called the pore throat. The larynx, as shown in the following figure b) restricts the fluid flow in the ground [2] . When the diameter of the pore throat is large, the movement of the fluid is smooth, otherwise it is blocked.
Schematic diagram of fluid flow in the pores of sediments | The fluid is stored and flowed in the pores, and the size of the pore throat is an important index restricting the flow. Photo source @ Zurich Federal Institute of Technology (ethz.ch), subject to change
Conventional oil and gas are stored in rocks with large pore throat diameters (micron, μm) , which are easy to flow and can be developed by traditional technology. Shale oil and tight oil and gas are stored in rocks with smaller pore throat diameters (nanoscale, nm, 1μm = 1000nm) , which are not easy to flow. Traditional It is difficult for technology to effectively mine [9] . The backs of different sized throats correspond to a seriesDifferent geological details, such as different types of storage rocks, different storage locations, and different storage areas.
Schematic diagram of the relationship between oil and gas types and pore throat diameters of storage space The diameters of pore throats in space are different, and the reason for this difference is the different geological characteristics of different reservoir rocks. 图 源 @ 资料 [7]
Generally speaking, conventional oil and gas are more active underground, can flow slowly in the rocks, find suitable habitats, and form oil and gas reservoirs of different sizes. People can use vertical drilling for efficient production. However, this method is not effective in the face of shale oil and gas resources and tight oil and gas resources that are not easy to flow, and people need a new technology to develop such shale and tight oil and gas resources.
Schematic diagrams of conventional oil reservoirs and unconventional oil and gas reservoirs | Unconventional oil and gas reservoirs are generally larger than conventional oil and gas reservoirs, and their characteristics are also very different, so different Mining technology, such as horizontal wells in the picture. Picture source @WSGS | Wyoming State Lands Bureau [3], subject to change
The following stories are familiar to everyone: With its strong technology and industrial strength, the United States has taken the lead in developing and commercializing horizontal well fracturing technology . This technique can significantly increase the contact area between the well and the formation.Make up for the lack of underground oil and gas fluidity, so that shale / tight oil and gas in a larger area of rock can be effectively used.
Schematic diagram of the difference between a horizontal well and a vertical well | A vertical well can only effectively use a small layer of stratum, but a horizontal well can use a large stratum. Figure source @ conchoenergy.net, subject to change
At the same time as horizontal wells increase contact area, segmented fracturing crushes a large piece of underground rock to release the oil and gas hidden inside the rock to the greatest extent, thereby obtaining effective collection.
Fracturing horizontal well pattern is equivalent to breaking a layer of stratum. | Only a few well sites on the ground can be manufactured by special drilling methods. Well pattern, then fracturing a large area of formation to efficiently extract oil and gas. The white “flocs” in the picture indicate pressure fractures in the underground rock, and it can be seen that the term “broken stratum” is not false. Figure source @ fractracker.org [10]
In the first decade of the 21st century, the United States took the lead in the large-scale development of shale (oil) gas and tight oil and gas resources, and rapidly expanded its frontiers for oil and gas exploration. In 2008, when the subprime mortgage crisis broke out in full, the U.S. petroleum industry thrived. The annual oil output stopped the downward trend for 24 consecutive years and resumed. [7-8] .