【摘要】 辽西中生代义县旋回火山作用可以划分成 4个亚旋回 ,每个亚旋回火山喷发都有不等量的火山碎屑物和熔岩形成。火山爆发作用对生物生存环境产生两方面的影响 ,一方面火山喷发作用形成一定量的H2 O、SO2 、SO3 等硫化物气体 ,是火山喷发烟雾及火山硫酸盐气溶胶的主要物质成分 ,由于硫化物气体上升进入大气层而发生氧化反应 ,形成硫酸盐气溶胶 ,对太阳产生折射 ,使生物死亡。H2 S、SO2 、SO3 、HCl和HF等气体和As、Hg的存在都能造成水体和植物的污染 ,使生物死亡。另一方面火山作用间歇期为生物提供生存的时间和活动的空间。火山作用停止以后 ,火山口附近通常形成大量的温泉和较大的湖泊 ,给生物提供了良好的生存环境 ,使生物在新的环境下重新繁盛。更多还原

【Abstract】 The Yixian volcanic eruption cycle in the Mesozoic volcanic basin of western Liaoning can be divided into four subcycles, and there are some pyroclastic debris and lava in each eruption subcycle. The volcanic eruption made an impact on the existing environment of living things in two ways. On the one hand, it formed certain amounts of sulfide gases such as H 2O, SO 2 and SO 3 which constituted the main composition of volcanic smog and H 2SO 4 aerosol. When the sulfide gases went up into the atmospheric layer, the oxidation reaction occurred and formed H 2SO 4 aerosol. This caused the refraction of the sunlight and the death of living things. The gases such as H 2S, SO 2, SO 3, HCl and HF and the elements like As and Hg could pollute waters and plants, thus responsible for the death of living things. On the other hand, the intermittent periods of volcanism could provide living things with time for existence and room for activity. After the end of the volcanic eruption, a lot of hot springs and large lakes were formed near the crater, which could supply the living things with excellent existing environment and make them flourish again in the new environment.更多还原