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The origin, characteristics and geological significance of the collapsed-paleocave systems in the Sinian to Permian carbonate strata in Central Sichuan Basin are studied based on 3D seismic interpretation and attributes analysis, as well as imaging logging and cores. Collapsed-paleocave systems are distributed in the Sinian to Permian carbonate strata vertically and along the ends, releasing offsets and intersections of faults horizontally. On profile, they occur as seismic events push-down. The collapsed-paleocave systems mainly originated from fault movements at three main structural phases, the first stage of Tongwan, the second and third stages of Tongwan and the Early Caledonian, and eventually got into shape at the end of the Permian. The collapsed-paleocave systems are featured by multi-layers, wide distribution and good reservoir quality, in which reservoir space is made up of pre-existing pores, structure genetic fractures and collapsed genetic fractures. According to seismic response characteristics, three types of collapsed-paleocave systems are identified in this area, including multi-layer cave system collapsed complex, multi-layer cave passage collapsed system and intra-bed cave collapsed system. The multi-layer cave system collapsed complex and multi-layer cave passage collapsed system in the overlying deformed layers where fractures are widely distributed may be the favorable targets for future exploration. Key words: collapsed-paleocave systems, collapse mechanism, concentric circular faults, Sinian to Permian, Central Sichuan Basin

[Objective] Based on the United Nations 2030 Sustainable Development Goals (SDGs), this study aimed to assess the resilience of the social-ecological system and explore the strategies to enhance the resilience of the social-ecosystem system in energy-rich areas, in order to promote sustainable transformation and high-quality development in these areas. [Methods] This study constructed a social-ecological system resilience assessment matrix applicable to energy-rich areas based on the resilience theory, and examined the change of social-ecological system resilience and optimization and enhancement strategies in the Shanxi-Shaanxi-Inner Mongolia energy-rich area from 2005 to 2020. [Results] The results show that: (1) From 2005 to 2020, the overall resilience of the social-ecological system in Shanxi-Shaanxi-Inner Mongolia energy-rich area showed an upward trend. The resilience of the socioeconomic system showed a trend of decreasing first then rising, the resilience of the natural resources system showed a trend of increasing then decreasing, while the resilience of the ecological environment showed an increasing trend year by year. (2) The resilience of the social-ecological system exhibited phased characteristics under the influence of subsystem resilience in the study area. In the preparation and recovery stage, the improvement of social-ecological system resilience mainly benefited from the improvement of the ecological environment; In the coping and adaptation stage, the contribution of socioeconomic development to the resilience of regional social-ecological system was prominent. (3) The resilience pattern of the social-ecological system in the Shanxi-Shaanxi-Inner Mongolia energy-rich area has undergone significant changes, with a significant increase in cities with higher resilience. The socioeconomic resilience showed a pattern of high in the northwest and low in the southeast. The resilience of natural resources exhibited spatial characteristics of low in the northwest and high in the southeast. The ecological environment resilience showed a spatial pattern of high in the north and low in the south. (4) The lack of natural resources subsystem resilience was the key factor that restricted the improvement of resilience of the social-ecological system in the study area. [Conclusion] It is necessary to establish a collaborative governance mechanism of “stages + factors + systems + areas” in line with the United Nations 2030 Sustainable Development Goals (SDGs), aiming to continuously improve the resilience of the social-ecological system in the energy-rich area through various paths, such as accelerating the transformation and upgrading of resource-based economy, improving the efficiency of energy and resource utilization, improving the livelihood support system, and promoting ecological environment protection and restoration.