Language
Country/Area
No result found
Sound waves that shook the Earth: How geologists use seismic waves to find oil?
Petroleum, a fossil fuel from the depths of the earth, has an impact on modern society that cannot be ignored. It is formed by the aggregation of debris, algae and sediment under high pressure, usually at the bottom of shallow seas. In order to obtain these precious resources, geologists and geophysicists use various advanced technologies to locate potential oil fields, and the use of seismic waves is one of the key technologies.
Geologists use seismic wave technology to reveal the secrets deep in the earth and help us find oil reservoirs.
Locating Oil Fields: The Magic of Seismic Waves
Positioning methods commonly used by geologists include source blasting and passive observation. The former is to conduct a small explosion underground and observe the subsequent seismic wave reflection. This process can provide information on the underground geological structure. Passive methods, on the other hand, use naturally occurring seismic waves to collect data. Additionally, instruments such as gravimeters and magnetometers are used for exploration.
After detecting the potential of an oil field, geologists begin drilling, digging long holes to obtain further oil. In the history of the United States, oil from some oil fields once naturally emerged from the ground, but currently the available oil fields are limited, especially in Alaska, which has been mostly exhausted.
From Drilling to Extraction: Oil’s Journey
The drilling process is the first step in oil extraction. Oil wells are drilled deep into the earth and steel pipes are installed to maintain the structural stability of the borehole. A hole will be opened at the bottom of the borehole to allow oil to enter the well, and a valve device called a "Christmas tree" will be installed to adjust pressure and control flow.
Drilling is not only a technical challenge, but also a game of price fluctuations and market demand.
The oil extraction process can be roughly divided into three stages: primary recovery, secondary recovery and enhanced recovery.
Primary recycling
In the primary recovery stage, natural forces within the formation push the oil upward. These forces include the natural supply of water, the expansion of natural gas and the influence of gravity. The recovery rate at this stage is usually between 5% and 15%.
Secondary recycling
Over time, the internal pressure of an oil field gradually decreases. When natural forces are insufficient to push the oil to the surface, secondary recovery methods are used. This involves injecting water or gas into the formation to increase the pressure to increase the flow rate of oil and gas. .
The recovery rate of secondary recycling increases to an average of 35% to 45%.
Enhanced recycling
Enhanced or three-stage recovery methods further improve the fluidity of oil, including thermal enhanced oil recovery technology (TEOR), which often uses steam injection to reduce the viscosity of the oil and improve extraction efficiency.
For example, in the Midway Sunset Oilfield in California, the hot injection method successfully increased oil recovery and contributed to the region.
Challenges of oil extraction: safety and health
Workers in the oil and gas extraction industry face a unique set of health and safety challenges. According to research, between 2003 and 2013, although the overall occupational fatality rate decreased, work accidents in the oil and gas extraction industry increased, with traffic accidents and equipment contact accidents being the main causes of death.
Faced with serious safety issues, the industry urgently needs to take more effective hazard control measures.
Impact on the environment
The burning of oil releases large amounts of carbon dioxide, which has become a major culprit of global climate change. Oil spills that may occur during oil extraction and transportation also cause irreparable damage to the marine environment.
Conclusion
Oil extraction is the result of the combination of technology and natural resources, but the environmental and safety considerations hidden behind it cannot be ignored. In the face of increasing energy demand, can we find more sustainable ways to reduce the burden on the environment?
