山东昌乐-临朐火山岩孔隙系统研究

Studies on the fracture systems in the volcanic rocks, Changle-Linqu region, Shandong

昌乐 -临朐地处山东省中部 ,位于郯庐断裂带的沂沐断裂段。该地区分布着两百余座大大小小的火山 ,形成于中新世、上新世和更新世。通过对该区的地质背景、火山岩的分布、火山岩相及其裂缝和孔隙发育特征的详细研究 ,识别出四种(四个 )主要的孔隙系统 :(1)火山通道相 (火山颈相 ) ,连通宏观半充填柱状层状孔隙系统 ;(2 )火山熔岩相或溢流相 ,复合型(连通 -半连通及宏观 -微观、全充填 -半充填 -未充填 )网状孔隙系统 ;(3)火山爆发相 ,复合型孔缝孔隙系统 ;(4 )火山喷发沉积相 ,沉积孔隙型孔隙系统。

The Changle-Linqu region is situated in the middle Shandong Province, and at the Western block of the Yishu fault belt of Tanlu Fault. There are more than 200 volcanic hills, mainly occurring in the Miocene, Pliocene and Pleistocene in the region. The geological settings, occurrences, facies and the developing characteristics of the fractures and pores of volcanic rocks are systematically investigated in this paper. Four main pore systems are recognized: (1) the volcanic channel facies pore system, characterized by the well developed macro-fracture, semi-fill and pillar-plane joints; (2) the volcanic lava facies net pore system composed of various kind, scale, occurrence, evolution of joints, fractures and pores; (3) volcanic eruption facies pore system, and (4) eruption-deposition facies pore system. The quantitative models of the pore systems are also primarily established.