Tensional normal fault is generally consist of fault core and damaged zone, fault core associated with fractures, connected pores and the induced fractures of damaged zone can be used as a channel for fluid conduit. The fault activity has episodic feature, and a cycle of faulting can be divided into three stages, active period, active-intermitient trandition period and intermitient period, the advantage conduit channel is associated with fractures in faulting period, generally, the main conduit mechanism is episodic migration under the control of the " seismic pumping" ; the conduit capacity in intermitient period is weak, and the channel is connected to pores, following the slowly seepage mechanism under the control of buoyancy; active-intermitient trandition period has some characteristics of active period and intermitient period, and the conduit channel is the induced fractures of damage zone. The fault conduit has three directions of migration component, vertical direction along fault, strike direction along fault and across the direction of the fault plane, correspondingly, current fault conduit divide into "two types and four kinds" , including conduit along the fault plane and conduit across the fault plane, which the type of conduit along the fault plane can be also divided into three kinds, they are vertical upward conduit along the fault, conduit along the fault strike and "reversed" conduit along the fault. The type of vertical upward conduit along the fault is the most important form of fault conduit, which can be further divided into three sub-kinds, namely the linear conduit, "Y"-type conduit and like flower-shaped conduit, the largest proportion is like flower-shaped conduit. The specific conduit form and direction depends on the configuration of the fault and both sides of the formation in faulting and sum of vector of multiple migration force, resistance.%张性正断层断裂带一般具有二分结构,即断层核和破裂带,断层核伴生裂缝、连通孔隙及破裂带诱导裂缝均可作为输导流体的通道.断裂活动具有幕式的特征,一次活动周期可以分为活动期、活动—间歇过渡期和间歇期3个阶段,断裂活动期以伴生裂缝为优势输导通道,一般以“地震泵”控制下的幕式运移机制为主；活动间歇期输导能力较弱,通道为连通孔隙,遵循浮力控制下的缓慢渗流机制；而活动—间歇过渡期兼具有活动期和间歇期的部分特征,主要输导通道为破裂带诱导裂缝.断裂输导具有3个方向的运移分量,即沿断裂纵向方向、沿断裂走向方向和横穿断层面方向,与此相对应,目前断裂输导形式分为“2型4类”,包括沿断层面输导和横穿断层面输导两大类型,其中,沿断层面输导型又可分为沿断裂纵向向上输导、沿断裂走向输导和沿断裂向下“倒灌”式输导3类.沿断裂纵向向上输导是目前最重要的断裂输导形式,进一步分为3种亚类,即线性输导、“Y”形输导和似花状输导,似花状输导所占比例最大.具体的输导形式及方向取决于活动时期断裂与两侧地层的配置关系及多种运移动力、阻力的矢量合.
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