Eruption and emplacement of flood basalt: An example from the large-volume Teepee Butte Member, Columbia River Basalt Group
Eruption and emplacement of flood basalt: An example from the large-volume Teepee Butte Member, Columbia River Basalt Group
复制标题
溢流玄武岩的喷发和侵位：以哥伦比亚河玄武岩群大体积 Teepee Butte 段为例
DOI：
--
复制
发表时间：
1992
期刊：
影响因子：
--
通讯作者：
T. Tolan
中科院分区：
文献类型：
--
作者：
S. Reidel;T. Tolan
蒂皮丘成员的流动，格兰德朗德玄武岩，从华盛顿东南部，俄勒冈州东北部和爱达荷州西部的喷口系统发出。三个不同的玄武岩流爆发：石灰窑急流流，约瑟夫溪流，和普鲁伊特提请流。这些可绘制的流量加在一起覆盖超过52，000 km[sup 2]，体积超过5，000 km[sup 3]。在华盛顿的约瑟夫峡谷中，约瑟夫溪流的部分喷口系统暴露在横截面中;它是已知的保存最好的哥伦比亚河玄武岩群喷口复合体之一。喷口复合体横截面约1公里，高30米，由夏威夷型火山作用的沉积物组成。通风口不对称;东部的壁垒由夹层火山碎屑沉积物和薄pahoehoe流组成;西部的壁垒完全由pahoehoe流组成。流动的T形丘成员组成均匀，并作为片状流，每个有几个局部流动单元。我们的研究支持线性喷口系统和向西帕卢塞斜坡，沿着与大量的熔岩流，在控制哥伦比亚河玄武岩群流量的分布的重要性。其他因素，包括活动裂缝段的数量和更多的地形，修改了流动的形状和流动单元的数量。参考文献45篇，图19，2个标签。«少
Flows of the Teepee Butte Member, Grande Ronde Basalt, issued from a vent system in southeastern Washington, northeastern Oregon, and western Idaho. Three distinct basalt flows were erupted: the Limekiln Rapids flow, the Joseph Creek flow, and the Pruitt Draw flow. Together these mappable flows cover more than 52,000 km[sup 2] and have a volume exceeding 5,000 km[sup 3]. A portion of the vent system for the Joseph Creek flow is exposed in cross section in Joseph Canyon, Washington; it is one of the best preserved Columbia River Basalt Group vent complexes known. The vent complex is about 1 km in cross section, 30 m high, and composed of deposits characteristic of Hawaiian-type volcanism. The vent is asymmetrical; the eastern rampart consists of intercalated pyroclastic deposits and thin pahoehoe flows; the western rampart is composed wholly of pahoehoe flows. Flows of the Teepee Butte Member are compositionally homogeneous and were emplaced as sheet flows, each having several local flow units. Our study supports the importance of linear vent systems and the westward Palouse Slope, along with the large-volume lava flows, in controlling the distribution of Columbia River Basalt Group flows. Other factors, including the number of active fissure segments andmore » topography, modified the shape of the flows and the number of flow units. 45 refs., 19 figs., 2 tabs.« less