Geological Studies on the Mobile Belts of Asian-Pacific Ocean Region, Especially Tectonics of the South Island of New Zealand

亚太地区活动带特别是新西兰南岛构造地质研究

• 批准号: 02041063
• 负责人: SUZUKI Takashi
• 金额: $ 6.4万
• 依托单位: Kochi University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02041063/
• 关键词: South Island; New Zealand; Caples terrane; Torlesse terrane; radiolarian fossils melange; geochemistry of greenstones

This note is a report of a research joint project on the Otago coast section in the South Island, New Zealand. The title of the project is "Kochi University-Otago University Joint Study of Accretion Complex Geology : Otago Coast Section". This field work was carried out from September to October, 1990. The main purpose of this study is to compare the accretionary process of the South Island in New Zealand with that of the Outer Zone of Southwest Japan in the framework of the mobile belts of Asian-Pacific Ocean regions and to elucidate tectonic histories of development of their geological structures.The methods applied in this study were as follows :(1) Construction of structural map along the coastline of the Chrystalls Beach area, southwest of Dunedin.(2) Collection of microfossil-bearing rock specimens to investigate radiolarian biostratigraphy,(3) Collection of typical rock specimens and investigation of their petrography and petrochemistry, and(4) Synthesis of all new data on the g … More eology and petrology of the study area.Following points are interested in the preparation of future reports and papers for publication arising from our project,(1) Tuffaceous component : Basaltic hyaloclastites may be present in the pillow-lava metabasite association. Much more problematic is the volumetric contribution of more siliceous ash to the cherty sediments and especially to the pale gray, greenish gray, and pink shaly metasediments. There is good evidence for graded ash beds, a few centimeters thick, accompanied and followed upwards by glass shards. These no doubt originated from distant plinian eruptions in the acid andesite to ryolite composition range,(2) Terrane affinities of the Chrystalls Beach Complex : Various workers have tended to assume in the past that the Chrystalls Beach complex is part of the Caples terrane. Nevertheless as shown by some of our petrological study, the relative proportions of detrital quartz, Plagioclase, and K-feldspar, and in particular the dominance of quartz and sparsity of volcanic lithic fragments in the metasandstones of the Chrystalls Beach Complex, are very different from those in known units in the Caples terrane. The association with pillow basalts, cherts, and light-coloured shaly rocks fits better with Torlesse or Aspiring than with Caples,(3) Phosphatic nodules : Two types of phosphatic nodules are present. One contains radiolaria in greater or less abundance, and extremely little terrigenous detritus. The other type contains abundant silt or fine sand grains. From the absence of terrigenous detritus in the first type, we suspect they must form as a crust on the sea floor during pauses in turbidite sedimentation,(4) Penetrative deformation, and (5) K-Ar dating. Less

本说明是新西兰南岛奥塔哥海岸地区的一个研究联合项目的报告。该项目的标题是“高知大学-奥塔哥大学联合研究增生复杂地质学：奥塔哥海岸剖面”。本次野外工作于1990年9月至10月进行。本次研究的主要目的是比较亚太海域活动带框架内新西兰南岛与日本西南外带的增生过程，阐明其地质构造发展的构造历史。本研究采用的方法如下：（1）沿太平洋地区海岸线绘制构造图。 达尼丁西南部的 Chrystalls 海滩地区。(2) 收集含微化石的岩石标本以研究放射虫生物地层学，(3) 收集典型岩石标本并研究其岩石学和石油化学，以及(4) 综合有关研究区域地质学和岩石学的所有新数据。以下几点有兴趣准备未来的报告和论文以供出版 由我们的项目产生，(1) 凝灰质成分：玄武质透明碎屑岩可能存在于枕状熔岩变碱岩组合中。更成问题的是更多的硅质灰分对燧石沉积物，特别是对浅灰色、绿灰色和粉红色页岩变沉积物的体积贡献。有充分的证据表明分级灰床有几厘米厚，并伴随着玻璃碎片向上延伸。这些无疑源自酸性安山岩到流纹岩成分范围内的遥远普林尼式喷发。(2) Chrystalls Beach 复合体的地体亲和力：过去，各种研究人员倾向于假设 Chrystalls Beach 复合体是 Caples 地体的一部分。然而，正如我们的一些岩石学研究所示，碎屑石英、斜长石和钾长石的相对比例，特别是 Chrystalls Beach Complex 变砂岩中石英的主导地位和火山岩碎片的稀疏性，与 Caples 地体已知单元中的比例有很大不同。与枕形玄武岩、燧石和浅色页岩的关联更适合 Torlesse 或 Aspiring，而不是 Caples。(3) 磷酸结核：存在两种类型的磷酸结核。其中一种含有或多或少丰富的放射虫，以及极少量的陆源碎屑。另一种类型含有丰富的淤泥或细砂粒。由于第一种类型中不存在陆源碎屑，我们怀疑它们必须在浊积岩沉积暂停期间在海底形成地壳，(4) 穿透变形，以及 (5) K-Ar 测年。较少的

项目成果

HADA,S.,LANDIS,C.ET AL.: "Mesozoic radiolarian ages of the Chrystalls Beach Complex,South Island,New Zealand." Geology.

HADA,S.,LANDIS,C.ET AL.：“新西兰南岛 Chrystalls 海滩综合体的中生代放射虫时代。”

SUZUKI,T.,COOMBS,D.ET AL.: "Geology and structure of the Chrystalls Beach Complex,in the South Island,New Zealand,with special reference to the question of the title to the complex."

SUZUKI,T.,COOMBS,D.ET AL.：“新西兰南岛 Chrystalls 海滩综合体的地质和结构，特别涉及该综合体的所有权问题。”

Hada, S. , Landis, C. et al.: "Mesozoic radiolarian ages of the Chrystalls Beach Complex, South Island, New Zealand." Geology.

Hada, S.、Landis, C. 等人：“新西兰南岛 Chrystalls 海滩综合体的中生代放射虫时代。”