【摘要】 长白山天池火山周边的11个钻孔资料揭示了长白山天池火山的喷发序列和岩浆演化过程。天池火山的喷发序列分为3个旋回:早期旋回喷发于上新世至早更新世,对应着周边地区的造高原喷发,天池火山熔岩盾主体开始形成,岩浆演化顺序是粗面玄武岩到粗面岩;中期旋回是早更新世的玄武岩浆演化到粗面岩和粗安岩(相当于小白山组);晚期旋回是从更新世到全新世,老房子小山组的玄武岩演化到白头山组粗面岩及碱流岩。在粗面质岩浆喷发过程中,有寄生火山的玄武质岩浆伴随喷发。全新世内天池火山千年大喷发主体由碱流质火山碎屑堆积物构成,松散堆积物的钻孔堆积层序表明,天池火山在全新世至少发生过两期巨型造伊格尼姆岩喷发。更多还原

【Abstract】 Based on the data of 11 boreholes around Tianchi Volcano of Changbai Mountain, the paper describes the eruptive sequence and magma evolution of Tianchi Volcano. 3 cycles can be found from the eruptive sequence. The early cycle dates back to Pliocene to early Pleistocene, when the surrounding plateau-forming eruption happened and the main body of the lava shield of Tianchi Volcano was formed. Magma evolved from trachybasalt to trachyte. The middle cycle (early Pleistocene) magma evolved from basaltic magma to trachytes and trachyandesites that made up the Xiaobaishan Formation. The late cycle (from Pleistocene to Holocene) comprises the main edifice of the Tianchi stratovolcano. The basaltic magmas of the Laofangzixiaoshan Formation evolved to trachyte, even to comendite, of the Baitoushan Formation. There are some parasitic basaltic eruptions during the trachytic magma eruption. There existed a gigantic ignimbrite-forming eruption of Tianchi Volcano before the Millennium eruption.更多还原