Paradoxical pseudotachylyte – Fault melt outside the seismogenic zone
Paradoxical pseudotachylyte – Fault melt outside the seismogenic zone
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矛盾的假速水岩——地震带外的断层融化
DOI：
10.1016/j.jsg.2011.11.016
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发表时间：
2012
影响因子：
3.1
通讯作者：
J. White
中科院分区：
文献类型：
--
作者：
J. White
断层产生的熔体，假玄武玻璃，是古地震断层的一个既定指标。现有的共识是，在经典的孕震带内发生的岩浆诱发熔融形成对比的争论假玄武玻璃如何形成的韧性制度。这个问题的核心是是否所有的假玄武玻璃起源于压力依赖的摩擦熔体沿着滑动面，或者如果压力无关的过程中有其形成的作用。传播到更深的地壳水平的高速滑动提供了一个令人满意的解释，在深度的假玄武玻璃，但本身并不合理的地震成核以外的经典孕震区。加拿大新斯科舍省米纳斯断裂带的假玄武玻璃被用来证明在下地壳条件下与断裂有关的熔体的形成和保存。显微结构保留强烈的位错滑移的证据，最小的攀登，和韧性解聚的主机;后者是一致的Peierls应力控制的滑移制度与晶内变形。目前尚不清楚晶体塑性是否只是作为一个偶然的阶段，以破裂和高速滑移或本身负责不稳定性和热瞬态。加速塑性滑动导致破裂和无应力蠕变爆发（震颤）之间存在相似之处，强调了深部断层的机械复杂性，以及需要将考虑扩展到简单的脆-韧性反应之外。地震爆发的发生属于“矛盾”的假玄武玻璃的深度范围内，并提供了一个活动构造和地质记录，值得检查的间接联系。
Fault generated melt, pseudotachylyte, is an established indicator of palaeoseismic faulting. The existing consensus that frictionally induced melting occurs within the classic seismogenic zone contrast the contention over how pseudotachylyte forms within the ductile regime. Central to this issue is whether all pseudotachylyte originates as pressure-dependent frictional melt along slip surfaces, or if pressure-independent processes have roles in its formation. Propagation of high-velocity slip into deeper crustal levels provides a satisfactory explanation for pseudotachylyte at depth, but does not of itself rationalize earthquake nucleation outside the classic seismogenic zone. Pseudotachylyte from the Minas Fault Zone, Nova Scotia, Canada is used to demonstrate the formation and preservation of fault-related melt under lower crustal conditions. Microstructures retain evidence of intense dislocation glide with minimal climb, and ductile disaggregation of the host; the latter are consistent with intracrystalline deformation in the Peierls stress-controlled glide regime. It remains unclear whether the crystal plasticity serves only as a precursory stage to rupture and high-velocity slip or is itself responsible for both instability and the thermal transient. There are similarities between accelerating plastic slip leading to rupture and aseismic creep bursts (tremor) that emphasize the mechanistic complexity of deep faulting, and the need to extend consideration beyond that of a simple brittle-ductile response. The occurrence of tremor bursts fall within the depth range of “paradoxical” pseudotachylyte and provides a circumstantial link between active tectonics and the geologic record that merits examination.
含白云母石英岩中的假速晶石：同震摩擦引起的石英熔化和塑性变形
影响因子：
3.1
作者：
Bestmann;Pennacchioni;Göken;de Wall
通讯作者：
de Wall