关键词: 黑龙江, 五大连池, 现代火山, 气体地球化学

Abstract: A systematical study of geochemical characteristics of gases in Wudalianchi volcanic area leads us to find that the main component of the gases is CO₂ and minor components are rare gas He,microgas H₂ and radioactive gas Rn.The gases are characteristic of post eruption volcanic gases.In plane distribution,CO₂ ejects in Laoheishan and Huoshaoshan latest eruption activity zone and tectionic activity area.The formation conditions and origin of CO₂ are analysed,and release amount of CO₂ is also roughly estimated.From February to April,1988,H₂ in the South Spring exhibits large-amplitude positive anomaly variation.We think it has ralation with nearby small earthquake cluster.The discover and study of a gas hole in ice cave at Laoheishan volcanic crater is important for monitoring and studying future volcanic activity.The gas from the volcanic gas hole is a mixed gas composed of He,H₂ and CO₂.We think this volcanic gas hole is related with deep structure and lalest volcanic eruption.

Key words: Heilongjiang, Wudalianchi, Recent volcano, Gas geochemistry