The Alpine Fault, New Zealand: Surface Geology and Field Relationships
The Alpine Fault, New Zealand: Surface Geology and Field Relationships
复制标题
新西兰阿尔卑斯断层：地表地质和野外关系
DOI：
10.1029/175gm09
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
A. Cooper
中科院分区：
文献类型：
--
作者：
R. Norris;A. Cooper
阿尔卑斯断层是太平洋-澳大利亚板块边界的陆地部分。一般来说，断层有一条简单的直线，走向约055°，适度向东倾斜，但在中心地区，它是连续分割的。晚第四纪走滑速率为23 ~ 25 mm/yr，中部走滑速率约为10 mm/yr，南北递减，Jackson Bay西南部为零。由于斜滑作用，糜棱岩在现今迹线以东约1公里宽的断裂带中从约25公里处被挖掘出来，在浅层靠近断层处经历了强烈的碎裂作用。假硅藻土是由层状硅藻土组合优先熔融产生的。韧性剪切应变高，在超长岩中可达200-300。变质带和伟晶岩群在上盘位置的位移与约5 Ma以来糜棱岩内约100 km的右向韧性剪切一致。
The Alpine Fault forms part of the on-land Pacific-Australian plate boundary. Generally the fault has a simple straight trace, striking ca. 055° and dipping moderately eastwards, but in central areas it is serially partitioned. Late Quaternary strike-slip rates are 23-25 mm/yr, but dip-slip rates range from ca. 10 mm/yr in the central part, reducing north and south and reaching zero southwest of Jackson Bay. Due to oblique-slip, mylonites are exhumed from ca. 25 km in a ca. 1 km wide fault zone east of the present trace, undergoing intense cataclasis close to the fault at shallow levels. Pseudotachylytes are generated by preferential melting of phyllosilicaterich assemblages. Ductile shear strain is high, reaching 200-300 in ultramylonites. Displacement of metamorphic zones and a pegmatite swarm, with respect to their location in the hanging wall is consistent with ca. 100 km of dextral ductile shear within the mylonites since ca. 5 Ma.