Pseudotachylytes: Rarely Generated, Rarely Preserved, or Rarely Reported?
Pseudotachylytes: Rarely Generated, Rarely Preserved, or Rarely Reported?
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假速石：很少产生，很少保存，还是很少报道？
DOI：
10.1785/0120080114
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发表时间：
2009
影响因子：
3
通讯作者：
C. Persano
中科院分区：
文献类型：
--
作者：
J. Kirkpatrick;Z. Shipton;C. Persano
假玄武玻璃岩是已知唯一只在地震滑动速率下形成的断层岩，因此它在保存地震期间动态过程的直接证据方面是独一无二的。人们通常认为假玄武玻璃是罕见的，争论集中在它是很少生成还是通常生成但很少保存。我们目前的领域和电子显微镜观察的八个新的pseudotachylytes断层在内华达州，以前一直是许多详细的研究断层生长和力学的重点。这些假玄武玻璃的范围从丰富和容易识别的露头是不可能识别没有显微镜观察。我们的数据表明，pseudotrachylytes是更常见的内华达州比以前报道的。我们认为，pseudotachylytes可能存在于许多断裂带，但仍然没有报道，主要是由于在现场识别非常薄或返工pseudotachylytes的困难，因此，使用这些断层岩来解释动态地震过程必须重新审视。
Pseudotachylyte is the only fault rock that is known to form exclusively at seismic slip rates, so it is unique in preserving direct evidence of the dynamic processes in action during earthquakes. It is commonly assumed that pseudotachylyte is rare, and debate has centered on whether it is rarely generated or commonly generated but rarely preserved. We present field and electron microscope observations of eight new pseudotachylytes from faults in the Sierra Nevada that have previously been the focus of many detailed studies of fault growth and mechanics. These pseudotachylytes range from being abundant and easy to recognize in outcrop to being impossible to identify without microscope observations. Our data show that pseudotachylytes are much more common in the Sierra Nevada than has previously been reported. We suggest that pseudotachylytes may be present within many fault zones but remain unreported primarily due to difficulty in identifying very thin or reworked pseudotachylytes in the field; and therefore the use of these fault rocks to interpret dynamic earthquake processes must be revisited.