机构地区: 中国地震局地质研究所
出 处: 《地震地质》 2012年第4期743-754,共12页
摘 要: 对腾冲打鹰山、马鞍山和黑空山的熔岩流进行详细地质勘察,发现存在3类熔岩流动方式:管状流动、"底侵"式流动和层状流动。管状流动出现于打鹰山熔岩中。熔岩管道中的温度由核心向表层递减,当表层冷却固结时,管道中的塑性熔岩继续前进,最终由表及里逐渐固结。马鞍山火山熔岩为渣状熔岩"底侵"结壳熔岩流动。结壳熔岩由表层向底部增生,早期熔岩固结形成结壳熔岩,晚期高温气液混合相的熔岩注入结壳熔岩之下的通道,最终固结形成渣状熔岩。黑空山熔岩为渣状熔岩层状流动。熔岩流顶部自碎形成的渣块在底部塑性致密熔岩的驼动下流动,在火口近源和中源形成顶部和底部都是角砾的渣状熔岩,在熔岩流的远端尽头,形成垂直于熔岩流动方向的条带状隆起。 Based on detailed field investigation, three lava flow styles are identified in the Dayingshan, Maanshan and Heikongshan in the volcanic field of Tengchong: pipe flow,inflated flow and laminar flow. Lava flows of Dayingshan are characterized by pipe flow. Heat lost gradually increased from the core to the edge of the flow pipe, resulting in lava consolidating gradually from the surface to the core. Lava of Maanshan is dominated by plane pahoehoe inflated by aa. The lava,in high temperature,was inflated into the lava tunnel as liquid-gas mixing phase,which generated aa. Heikongshan is featured by typical aa lava flow in the proximal phase and middle phase from the vent. The high-temperature plastic lava carried breccias on its top when advancing in a state of laminar flow,forming typical aa la- va flow sections with breccias on the top and bottom and dense lava in the middle. In the distal phase,the lava flow formed numerous strip-shaped uplifts of breccias.