Geological Study of radiolarian-bearing strata in New Zealand -Evolution and faunal change of southern hemisphere high latitude radiolarians

新西兰放射虫地层地质研究——南半球高纬度放射虫的演化与区系变迁

基本信息

批准号：
07041085
负责人：
SAKAI Toyosaburo
金额：
$ 6.85万
依托单位：
Utsunomiya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

Geological studies of the radiolarian-bearing strata at many localities in the North and South Island basement terranes in New Zealand were carried out. The aims of our study are to clarify evolution and faunal changes of southern hemisphere high latitude radiolarians from the Mesozoic and to establish ratiolarian biostratigraphy and magnetostratigraphy of late Cretaceous-Early Eocene interval in Wairarapa area. (1) In the Waipapa terrane, well-preserved Middle and Late Triassic radiolarians have been yielded from phosphatic concretions from the green siliceous argillite at Mahinepua Peninsula, North Island. This faunas include sphaeroidal pylomate forms of a high latitude affinity, and are very similar ones which have been reported from the Lower Ladinian of the Chrystalls Beach Complex (Caples terrane), South Island. (2) Upper Permian to Triassic radiolarian succession has been examined from the volcano-pelagic sequences on the Arrow Rocks of the Waipapa terrane. (3) The northwest co … More ast line of the Waiheke Island exposes two major fault bounded structural elements : Unit I : Dorerites and Pillow lavas associated with black and red cherts, and green argillites. Unit II : Blue and green argillites and terrigenous clastics. In Unit I,green argillites contain a Late Jurassic radiolarians of a non-Tethyan affinity and black cherts include abundant Spumellaria, which suggests a Jurassic age. In contrast to this, blue and green argillites in Unit II contain a Late Triassic radiolarian fauna. (4) The Lower and Middle Jurassic of the Kawhia sequences of the Murihiku terrane has been studied for establishing the radiolarian faunas of Gondwana origin. Well-preserved radiolarians of the Lower and Middle Jurassic have been yielded from the calcareous concretions within siltstones. (5) Siliceous green argillites of the Lower Triassic of the Maitai terrane along the Wairoa River, Nelson, South Island have been studied. The radiolarian faunas are meager and low-diversity. (6) A reconnaissance sampling for radiolarian biostratigraphy of the Upper Cretaceous to upper Paleocene has been carried out in three sections of the Wairarapa area, North Island. Less

对新西兰北部和南岛基底地下许多地区的宽阔的Stratta进行地质研究。我们研究的目的是阐明南半球高纬度放射多虫从中生代开始的进化和动物变化，并在Wairarapa地区建立了晚期白垩纪 - 近代二世时间隔的放射性生物描记术和磁性造影。（1）在Waipapa地座上，从北岛Mahinepua Peninsula的绿色二氧化硅Argillite的磷酸化混凝土中得出了保存完好的中间和晚三叠纪放射性药物。该动物群包括高纬度亲和力的sphaeroidal脊椎酸酯形式，并且是非常相似的，这些形式是从Chrystalls Beach Complex（Caples Terrane）的South Island的Ladinian报告的。（2）从Waipapa Terrane的箭头岩石上的火山 - 沿序列中检查了上二叠纪至三叠纪放射性的成功。（3）西北公司…Waiheke岛的更多AST线暴露了两个主要故障限制的结构元素：I单元：Dorerites和枕头熔岩与黑色和红色chers相关，以及绿色的灰泥。第二单元：蓝色和绿色的氩和陆原经典。在第一单元中，绿色仙女会包含一个侏罗纪晚期的侏罗纪放射性人物，黑色cher虫包括大量的spumellaria，这表明是侏罗纪的年龄。与此相反，II单元中的蓝色和绿色氩物包含晚期三叠纪放射性动物群。（4）Murihiku Terrane的Kawhia序列的下层和中间侏罗纪已研究过建立Gondwana起源的放射性动物群。硫磺的钙质混凝土产生了保存完好的下层和中部侏罗纪的放射虫。（5）南岛尼尔森纳尔逊河沿着梅泰山的下三叠纪的硅质绿色氩气已研究。放射性动物动物群很小，多样性。（6）在北岛的Wairarapa地区的三个部分进行了上白垩纪至上古时代的放射性生物描记摄影的侦察采样。较少的