山东省中生代玻璃质火山岩的岩石学和岩石化学特征

PETROLOGICAL AND PETROCHEMICAL CHARA CTERISTICS OF MESOZOIC GLASSY VOLCANIC ROCKS IN SHANDONG PROVINCE

摘要:

山东省中生代玻璃质火山岩类有玻璃熔岩(珍珠岩、松脂岩)和玻璃质火山碎屑岩(熔结角砾岩、熔结凝灰岩和晶屑凝灰岩等)两大类。玻璃熔岩和流纹质熔结凝灰岩、熔岩角砾岩属钙碱性岩系列,K_2O/Na_2O<1,Na_2O>K_2O,δ<3.3,DI为72.79—90.86。石英碱性(长石)粗面质、石英粗面质、石英安粗质、安粗质的玻璃质火山碎屑岩屑碱性岩系列,K_2O/Na_2O>1,Na_2O< FONT>

Abstract:

The Mesozoic glassy volcanic rocks fall into two major types, i. e. glassy lava (perlite, pitchstone) and glassy volcaniclastie rocks (welded breccia, ignimbrite, crystallinoclastic tuff, etc.…).The glassy lava and rhyolite ignimbrite and welded breccia are calc-alkalic rock series and characterized by K_2o/Na_2O<1, Na_2O>K_2O,σ<3. 3. DI=72. 79-90. 86.The glassy volcaniclastic rocks of alkaline (feldspathic) trachyte, quartz trachyte, quartz latiae and latite nature belong to the alkaline rock seri...