Seafloor geology and petrology in the oceanic to continental transition zone of the Kermadec-Havre-Taupo Volcanic Zone arc system, New Zealand
Seafloor geology and petrology in the oceanic to continental transition zone of the Kermadec-Havre-Taupo Volcanic Zone arc system, New Zealand
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新西兰克马德克-阿弗尔-陶波火山带弧系统海洋到大陆过渡带的海底地质学和岩石学
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
J. Baker
中科院分区：
文献类型：
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作者：
J. Gamble;I. Wright;J. Baker
在新西兰北部，大洋汤加-克尔马德克岛弧系大致走向NNE-SSW，并在Whakatane弧火山附近与新西兰的大陆架相交。Whakatane弧火山是一座海底建筑物，从周围海底上升约1000米。这里的一个重要的测深坡折与拟议的大洋-大陆过渡带重合。在Whakatane火山西北部，在Colville Knolls挖掘发现了变形的中生代(？)变质沉积岩，其岩石学和地球化学与新西兰陆上的Waipapa Terrane岩相似，从而证实了近海区域的范围和“大陆”地位。从陆壳到洋壳的过渡区在2000米等深线上有一条明显的坡折，大致平行于富裕湾的海岸线。这一边界的线性被一个定义明确的折返构造--Ngatoro盆地打破，它在这里被认为是东半球的南延展。
Abstract To the north of New Zealand, the oceanic Tonga‐Kermadec island arc system strikes roughly NNE‐SSW and intersects the continental shelf of New Zealand in the vicinity of the Whakatane arc volcano, a submarine edifice which rises around 1000 m from the surrounding seafloor. A major bathymetric slope‐break here coincides with the proposed oceanic‐continental transition zone. Northwest of the Whakatane volcano, dredging on Colville Knolls recovered samples of deformed Mesozoic(?) metasedimentary rocks, whose petrography and geochemistry resemble Waipapa Terrane rocks of onshore New Zealand, thereby confirming the extent and “continental” status of the offshore region. The transition zone from continental crust to oceanic crust is delineated by a marked slope‐break at the 2000 m isobath, oriented roughly parallel to the Bay of Plenty coastline. The linearity of this boundary is broken by a well‐defined reentrant structure, the Ngatoro Basin, which here is recognised as a southern extension of the ocea...