重庆市武隆县芙蓉洞是世界自然遗产,但随着旅游经济的快速发展,芙蓉洞的洞穴景观发生退化,影响了旅游业的可持续发展。本研究分析了温度、湿度、CO2浓度及洞穴通风等主要环境因子变化特征和规律,研究了洞穴景观退化机理,并提出其保护对...重庆市武隆县芙蓉洞是世界自然遗产,但随着旅游经济的快速发展,芙蓉洞的洞穴景观发生退化,影响了旅游业的可持续发展。本研究分析了温度、湿度、CO2浓度及洞穴通风等主要环境因子变化特征和规律,研究了洞穴景观退化机理,并提出其保护对策。游人和洞穴灯光释放的能量导致芙蓉洞内气温升高。由于洞内外的温度差和空气流通,洞穴内表现出“夏季高温、冬季干燥”的特征。洞穴CO2浓度会随游人进入的数量增加而明显升高。洞穴升温、灯光热量释放,及空气对流导致洞穴湿度降低,使景观产生干裂和风化等现象。气流带入的洞外气体及高浓度CO2溶解于水汽,溶蚀洞穴景观。洞穴灯光为苔藓类植物生长提供了条件,附着于洞穴景观的表面;以及洞穴大气粉尘的进入,致使洞穴景观暗沉发黑。洞穴内部环境保护能有效防止洞穴景观退化,保证游客健康旅游,实现旅游资源的可持续开发利用。Furong Cave in Wulong County of Chongqing is a world natural heritage, but with the rapid development of the tourism economy, the cave landscape of Furong Cave has been degraded, which has affected the sustainable development of tourism. In this study, the characteristics and rules of major environmental factors such as temperature, humidity, CO2 concentration and cave ventilation were analyzed, the mechanism of cave landscape degradation was studied, and the protection measures were proposed. The energy released by visitors and cave lights causes the temperature inside Furong Cave to rise. Due to the temperature difference and air circulation inside and outside the cave, the cave shows the characteristics of “high temperature in summer and dry in winter”. The CO2 concentration of the cave will increase significantly with the increase in the number of visitors entering the cave. The warming of the cave, the release of heat from lighting, and air convection lead to a decrease in humidity within the cave, causing phenomena such as drying, cracking, and weathering of the landscape. The gas outside the cave and the high concentration of CO2 brought by the airflow dissolve in the water vapor and dissolve the cave landscape. Cave light provides conditions for the growth of bryophytes, which adhere to the surface of the cave landscape;And the entry of atmospheric dust into the cave, causing the cave landscape dark and black. Cave interior environmental protection can effectively prevent the degradation of the cave landscape, ensure the healthy tourism of tourists, and realize the sustainable development and utilization of tourism resources.展开更多
我国煤层渗透率低且地质条件复杂,采用常规油气储层改造的开发方式难度大、技术适应性差。近年来,基于应力释放的煤层气改造新方法“煤层气水平井水力喷射造穴”很好地解决了这一技术瓶颈问题,但是造穴卸压—增渗的作用机制及其主控地...我国煤层渗透率低且地质条件复杂,采用常规油气储层改造的开发方式难度大、技术适应性差。近年来,基于应力释放的煤层气改造新方法“煤层气水平井水力喷射造穴”很好地解决了这一技术瓶颈问题,但是造穴卸压—增渗的作用机制及其主控地质因素尚不明晰。为此,考虑了煤岩层理和天然裂隙的影响,采用有限元—离散元耦合方法(Finite-Discrete Element Method,FDEM)建立了煤层气水平井扇形洞穴完井数值模型,探究了造穴后岩体的应力演化历程和储层的卸压—增渗机制,并对比分析了不同储层参数(孔隙压缩系数、储层强度、弱面强度和地应力场)对应力释放的影响规律。研究结果表明:(1)围岩演化过程为造穴后岩体收缩,储层发生应力重构,围岩强度逐渐降低,岩体内部发生新生裂隙萌生和原生裂隙扩展,形成开挖损伤区和应力释放区;(2)参数敏感性分析表明孔隙压缩系数是决定造穴完井储层适应性的关键,弱面强度、储层强度和地应力场分布决定了围岩的应力演化模式和裂缝扩展形态;(3)造穴卸压后储层增渗机制为穴周裂缝提升导流能力,储层应力释放提升基质渗透率。结论认为,模型首次综合考虑了地层特点、造穴过程和煤岩裂隙的影响,研究结果揭示了煤层造穴后的应力演化过程及其卸压、增渗作用机制,深化了对煤层气水平井洞穴完井增产机理的认识,对我国煤层储层改造具有重要的工程参考价值。展开更多
文摘重庆市武隆县芙蓉洞是世界自然遗产,但随着旅游经济的快速发展,芙蓉洞的洞穴景观发生退化,影响了旅游业的可持续发展。本研究分析了温度、湿度、CO2浓度及洞穴通风等主要环境因子变化特征和规律,研究了洞穴景观退化机理,并提出其保护对策。游人和洞穴灯光释放的能量导致芙蓉洞内气温升高。由于洞内外的温度差和空气流通,洞穴内表现出“夏季高温、冬季干燥”的特征。洞穴CO2浓度会随游人进入的数量增加而明显升高。洞穴升温、灯光热量释放,及空气对流导致洞穴湿度降低,使景观产生干裂和风化等现象。气流带入的洞外气体及高浓度CO2溶解于水汽,溶蚀洞穴景观。洞穴灯光为苔藓类植物生长提供了条件,附着于洞穴景观的表面;以及洞穴大气粉尘的进入,致使洞穴景观暗沉发黑。洞穴内部环境保护能有效防止洞穴景观退化,保证游客健康旅游,实现旅游资源的可持续开发利用。Furong Cave in Wulong County of Chongqing is a world natural heritage, but with the rapid development of the tourism economy, the cave landscape of Furong Cave has been degraded, which has affected the sustainable development of tourism. In this study, the characteristics and rules of major environmental factors such as temperature, humidity, CO2 concentration and cave ventilation were analyzed, the mechanism of cave landscape degradation was studied, and the protection measures were proposed. The energy released by visitors and cave lights causes the temperature inside Furong Cave to rise. Due to the temperature difference and air circulation inside and outside the cave, the cave shows the characteristics of “high temperature in summer and dry in winter”. The CO2 concentration of the cave will increase significantly with the increase in the number of visitors entering the cave. The warming of the cave, the release of heat from lighting, and air convection lead to a decrease in humidity within the cave, causing phenomena such as drying, cracking, and weathering of the landscape. The gas outside the cave and the high concentration of CO2 brought by the airflow dissolve in the water vapor and dissolve the cave landscape. Cave light provides conditions for the growth of bryophytes, which adhere to the surface of the cave landscape;And the entry of atmospheric dust into the cave, causing the cave landscape dark and black. Cave interior environmental protection can effectively prevent the degradation of the cave landscape, ensure the healthy tourism of tourists, and realize the sustainable development and utilization of tourism resources.
基金国家自然科学基金项目“青藏高原东南缘晚更新世以来地球关键带演化过程”(42361144879)“青藏高原及周缘新生代大陆风化沉积记录研究”(41991323)+4 种基金青藏高原第二次综合科学考察研究任务七“高原生长与演化”专题四“碰撞以来古地理格局与构造地貌过程”(2019QZKK0704)云南省科技领军人才项目“建设云南省地球系统科学重点实验室”(202005AB160008)云南省基础研究计划项目重点项目“滇西南晚更新世和平文化人类植物利用及环境适应性”(202301BF070001-005)兴滇英才支持计划“滇西史前人类植物资源利用及其环境适应性”Queensland-Chinese Academy of Sciences Collaborative Science Fund“Past Asian-Australian MonsoonVariability”(QCAS036,045GJHZ2023001MI)。
文摘我国煤层渗透率低且地质条件复杂,采用常规油气储层改造的开发方式难度大、技术适应性差。近年来,基于应力释放的煤层气改造新方法“煤层气水平井水力喷射造穴”很好地解决了这一技术瓶颈问题,但是造穴卸压—增渗的作用机制及其主控地质因素尚不明晰。为此,考虑了煤岩层理和天然裂隙的影响,采用有限元—离散元耦合方法(Finite-Discrete Element Method,FDEM)建立了煤层气水平井扇形洞穴完井数值模型,探究了造穴后岩体的应力演化历程和储层的卸压—增渗机制,并对比分析了不同储层参数(孔隙压缩系数、储层强度、弱面强度和地应力场)对应力释放的影响规律。研究结果表明:(1)围岩演化过程为造穴后岩体收缩,储层发生应力重构,围岩强度逐渐降低,岩体内部发生新生裂隙萌生和原生裂隙扩展,形成开挖损伤区和应力释放区;(2)参数敏感性分析表明孔隙压缩系数是决定造穴完井储层适应性的关键,弱面强度、储层强度和地应力场分布决定了围岩的应力演化模式和裂缝扩展形态;(3)造穴卸压后储层增渗机制为穴周裂缝提升导流能力,储层应力释放提升基质渗透率。结论认为,模型首次综合考虑了地层特点、造穴过程和煤岩裂隙的影响,研究结果揭示了煤层造穴后的应力演化过程及其卸压、增渗作用机制,深化了对煤层气水平井洞穴完井增产机理的认识,对我国煤层储层改造具有重要的工程参考价值。
