After more than 60 years of efficient development, the First Oil Production Plant of PetroChina Daqing Oilfield (hereinafter referred to as the First Oil Production Plant) has produced a total of 650 million tons of crude oil, with a geological reserve recovery rate exceeding 50%. Currently, the remaining geological reserves are highly dispersed, and how to accurately locate the remaining oil is the main topic for researchers. In the past two years, multiple blocks of the First Oil Production Plant have undergone tertiary oil recovery technology development, and the remaining layers are idle, with some remaining oil reservoirs hidden in "corners" that are not easy to discover. In response, researchers have achieved an increase of 200000 tons of oil by tracking and adjusting the precise release of sealed reserves. Recently, the reporter walked into the scientific research team of the First Oil Production Plant and gained a detailed understanding of the remaining oil excavation and extraction process. This development achievement is mainly attributed to the advancement of digital twin reservoir technology under the strategy of digital transformation and intelligent development of oil fields. This technology enables oil that is invisible and untouchable thousands of kilometers underground to be presented more clearly and stereoscopically on computer screens. In the past, where the reserves were and how to extract them required scientific researchers to determine development plans based on a small amount of information and professional knowledge, which is what petrologists often say 'oil is in the minds of geologists'. Nowadays, oil reservoirs have a new way of presenting themselves, with the internal parts of the reservoirs clearly visible and the development contradictions precise and clear, allowing technical personnel to stay indoors and fully understand the underground affairs of the reservoirs Zhou Changxiao, Director of the Multi disciplinary Department of the Geological Research Institute of the First Oil Production Plant, introduced to the reporter of Science and Technology Daily. The construction of a digital twin system for oil and gas reservoirs is considered the best solution for describing oil and gas reservoirs at present. After more than 60 years of development and construction, the total number of oil and water wells in the First Oil Production Plant has increased from a few hundred wells in the early stages of the war to the current 20000 wells; The density of well points has also increased from a few wells per square kilometer to over one hundred wells per square kilometer, and these oil and water wells high-density "connect" the kilometer rock layers. How can such a complex underground situation present the original distribution of oil reservoirs? Faced with this situation, the research team conducted a thorough investigation of 20000 wells one by one. On the basis of understanding the massive historical data, a huge flow of underground rock and oil layer information has been accumulated through geophysical exploration, drilling, logging, logging, testing, and development adjustments. In addition, they also applied computer technology to connect these data and pioneered the application of technical means such as reservoir 3D description and numerical simulation, gradually making the invisible underground "vivid" and "moving" underground entities into computer screens. Zhou Changxiao introduced that using the "twin" geological body can not only accurately determine the location and trend of remaining oil, implement "simulation development drills", efficiently deploy development well networks, target implementation of process technology, but also predict potential tapping effects, avoiding irreparable losses in practical operations. By utilizing these technologies, the First Oil Production Plant maximizes the quantification and restoration of real oil reservoirs, accurately characterizes the dynamic changes throughout the entire life cycle of the reservoir, and enables the continuous innovation and development of fine reservoir description technology, achieving leapfrog development in description accuracy. This will help us explore the potential tapping effects of different development models, and then screen out the most efficient and economical development models to maximize the utilization of various small oil layers and maximize the combat effectiveness of individual oil and water wells