Tight oil is the accumulation of oil trapped in the shale formation or transported to the interlayer in a very short distance. Tight oil has a broad prospect of exploration and development and has become an important replacement resource for conventional oil resources. The evaluation of structural characteristics of tight oil reservoirs is the hot spot and frontier of tight oil research. However, tight oil resources are formed uniquely, and their characteristics are different from those of conventional oil resources. The study on the structural characteristics of tight oil reservoirs is helpful to deepen the scientific understanding of tight oil reservoir systems. This paper reviews the main progress made in the evaluation of structural characteristics of tight oil reservoirs in recent years. The purpose of this paper is to deepen the systematic understanding of tight oil reservoir structure and enrich the understanding of the occurrence law and enrichment mechanism of tight oil resources, to promote the geological evaluation, exploration, and development of tight oil resources.
Water drive development is the most widely used and mature oil field development technology. Water drive development includes water flooding (water injection) and water injection huff and puff. The main reasons for the broad application of water drive development include: (1) injected water can drive crude oil wells, (2) water can be injected into strata relatively easily to increase reservoir energy, and (3) water resources have lower investment and operation costs. The driving development of more and more oilfields in China has entered the middle and high water cut stage, and the proportion of low-grade reservoirs with low permeability and low abundance is getting higher and higher, which makes the development more difficult. How to improve the effectiveness of the water drive and improve the efficiency of water drive is the key problem to be solved in oilfield water drive development. At the same time, under the condition of complex injection-production relationships and frequent dynamic changes of the displacement field, it can effectively tap the potential of remaining oil and improve the development effect of water drive, which puts forward higher requirements for water drive development technology. This paper summarizes the present situation of water-drive development technology in Chinese oilfields and puts forward some suggestions for the future development trend.
Climate change has a serious impact on the food crop ecosystem. Rice is not only an important food crop for human beings, but also one of the food crops sensitive to climate change. The research progress on the effects of climate change on rice in China is reviewed in this paper. Climate change significantly shifted the planting boundary of rice to the north, which shortened the growth and development period of rice, and then decreased the overall planting yield and quality of rice. The adverse effects of climate change can be dealt with through the adjustment of planting distribution, variety improvement, and technological improvement. In the future, climate change will further affect rice production. It is still necessary to strengthen the research on the impact mechanism of climate change and countermeasures to promote and ensure the sustainable development of rice. The purpose of this paper is to provide a reference for the assessment of the impact of climate change on rice and the sustainable development of rice.