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On December 17, with the machines humming in the constant-temperature laboratory, Zheng Jiabing, a technician from the Experimental Center of the Zhongyuan Oilfield Exploration and Development Research Institute, carefully placed a gray-brown rock core sample from well Wen 15-119 into the center of the MRI scanner’s probe. The blue indicator light turns on, and the screen begins to capture signals in real time. “By simulating different development methods, we observed the changes in residual oil within the core, providing support for studying the mechanism of oil recovery from the old Dongpu oilfield with heavy oil. ”Zheng Jiabing introduced. Core samples obtained from depths of several kilometers underground are the most direct \"physical evidence\" for understanding oil and gas reservoirs. Since the beginning of this year, Zhongyuan Oilfield has introduced large-bore, multi-scale nuclear magnetic resonance online equipment. Through continuous technical efforts, a comprehensive experimental support system has been established, covering everything from static characterization to dynamic simulation, as well as conditions ranging from normal temperature and pressure to high temperature and pressure. This system provides critical technical support for the accurate identification of reserves in unconventional oil and gas reservoirs and for improving recovery rates. Testing core samples is necessary to determine their \"health status.\" As oil and gas exploration and development move toward deeper levels and unconventional reservoirs, understanding the structure of the tiny pores within rocks and accurately assessing the flow capacity of oil, gas, and water within those pores has become crucial for improving the efficiency of developing complex reservoirs. “In medicine, magnetic resonance imaging involves using magnetic fields and radio frequency waves to scan the hydrogen atoms in the body, with images being generated from the electromagnetic signals they emit. ”Qi Guixue, a technical expert from the Exploration and Development Research Institute, said, “The principle behind using nuclear magnetic resonance on rock cores is the same.” Both oil, gas, and water contain hydrogen atoms. When the signals emitted by nuclear magnetic resonance equipment come into contact with the hydrogen atoms in the rocks, these atoms respond, allowing researchers to determine the distribution of oil, gas, and water within the rock core. After processing, intuitive spectral diagrams can be generated, from which the structure of tiny pores can be identified. ”More importantly, this technology is far more efficient than traditional methods. “In the past, analyzing the porosity and oil saturation of a rock core took days or even longer. With MRI technology, the testing can be completed in just a few dozen minutes, without damaging the rock core. The samples obtained after testing can be used for other experiments, resulting in a significant increase in the efficiency of sample utilization. ”Qi Guixue said. This MRI system increases the efficiency of single-core analysis by more than 10 times, with a testing precision at the micron level. Compared to the conventional helium method, it improves the accuracy of porosity measurement by approximately 14%, thereby facilitating the implementation of more effective measures to increase production. Customized solutions are developed to meet the specific needs of different reservoirs; compared to conventional reservoirs, the development of unconventional reservoirs requires more complex and diverse core analysis. To this end, the research team carried out a series of technical efforts to establish a standardized system, addressing the specific challenges associated with the development of various reservoir types. The team first clarified the relationship between MRI signals and porosity, and developed multiple standard procedures and interpretation charts that can be used directly. With these basic tools, the team can tailor solutions precisely to different types of reservoirs. Pressure flooding and well shut-in is a common extraction method in low-permeability reservoirs, but monitoring the effectiveness of well shut-in after pressure flooding has always been challenging. Today, thanks to magnetic resonance imaging technology, researchers can use dynamic MRI monitoring of fluid absorption after pressure flooding to accurately depict the movement patterns of fluids in the low-permeability reservoirs in the Pu84 area of the Dongpu old mining district and the Lianggan new mining area in Inner Mongolia, thereby providing reliable support for the dynamic adjustment of development plans. To address hard reservoirs such as shale and tight sandstone, the team developed a comprehensive NMR-sorption evaluation system. This system is akin to holding a fair \"performance competition\" among various chemicals; through nuclear magnetic resonance technology, it is possible to clearly and quantitatively determine which chemical formula penetrates deeper and provides a better oil-reducing effect, thereby offering a reliable basis for selecting the best chemical on-site. Online simulation is used to predict the “treatment effect”; in oil and gas development, the efficiency of displacement directly affects the ultimate recovery rate. Traditional methods require subsequent trial production or dynamic monitoring to evaluate development plans, which not only results in a long timeline and high costs but also leads to delayed adjustments. NMR online analysis technology can advance this process, essentially allowing for a \"pre-assessment of performance\" of the reservoir before development begins. To address the issues of water invasion and energy degradation in carbonate gas reservoirs in the Puguang area, the research team used this technology to conduct online simulation experiments for the entire process of carbon dioxide injection to replenish energy and control water levels. The results show that the injected carbon dioxide can form a steadily advancing \"gas wall\" within these hard and dense rocks; this wall can keep moving forward, breaking through the water barrier, replenishing the energy in the rock layers, and \"pushing\" the remaining gas from deeper layers to the surface. Through online MRI monitoring and quantitative analysis, the injection of carbon dioxide can replenish approximately 46% of the formation energy, significantly enhancing the drive capacity of the gas reservoir. Today, in the development of hard-to-reach reserves through gas injection, nuclear magnetic resonance online analysis technology enables a precise replication and evaluation of the displacement processes of various injection media such as carbon dioxide, natural gas, and nitrogen. This provides direct support for optimizing injection parameters and designing strategies for alternating gas and water injection, thereby facilitating a shift from experience-based approaches to precise prediction in development activities. Currently, the institute is working together with universities to develop intelligent spectrum analysis algorithms and build an intelligent analysis platform for big data from nuclear magnetic resonance in oil and gas reservoirs, thereby providing more intelligent decision-making support for oil and gas exploration and development.