...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Facies >Upper Devonian shoal-water delta integrated with cyclic back-reef facies off the Mowanbini Archipelago (Canning Basin), Western Australia
【24h】

Upper Devonian shoal-water delta integrated with cyclic back-reef facies off the Mowanbini Archipelago (Canning Basin), Western Australia

机译：西澳大利亚州Mowanbini群岛（坎宁盆地）外的上泥盆统浅水三角洲与循环后礁相整合

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The Oscar Range in Western Australia’s Canning Basin exhibits folded Proterozoic, quartzite, quartzite conglomerate, phyllite, and metavolcanic rocks that survive with positive relief. Facies of the Pillara Limestone were deposited around this relief during Late Devonian (Frasnian) time. A segment of the Great Devonian Barrier Reef with a linear reef margin strikes parallel to the outer paleoislands in the Mowanbini Archipelago. A more sheltered strait separates inner islands from the cratonic Devonian mainland on the Kimberley Block. Large fan-deltas emanated from the craton, but locally small shoal-water deltas prograded from a drainage basin on one of the larger paleoislands in the Oscar Range. That island is expressed today by local topography exhumed from beneath a cover of former Devonian, Carboniferous, and Permian strata. The Devonian shoal-water delta rests unconformably on tilted Proterozoic phyllite and incorporates abundant phyllitic debris accumulated under fluvial to shoreface conditions. Some quartzite pebbles and hydrothermal quartz were derived from a source more than a kilometer away. Rare gastropods and stromatoporoid fragments in the deltaic sediments were abraded from the adjacent reef margin. The clast-supported conglomerate in the exposed shoal-water delta is mapped over a distance of 130 m to within 15 m of the inner reef margin, exposed nearby on steeply dipping phyllite. A cyclic succession of mixed clastic and carbonate parasequences, 31.5 m in thickness, follows above a disconformity surface on the delta-top facies. The overall succession represents a minor fall in relative sea level associated with erosion of delta facies and a major transgression characterized by a retrograde parasequence stacking pattern. The succession shifts through siliciclastic-rich shoreface to intertidal distal back-reef facies, ending with a subtidal, siliciclastic-poor proximal back-reef facies. The study demonstrates how variability in sedimentary cycles is influenced by local paleogeographic constraints in an island system dominated by quartzite highlands and phyllite lowlands.
机译：西澳大利亚州的坎宁盆地的奥斯卡山脉展示出折叠的元古代，石英岩，石英岩砾岩，千枚岩和变火山岩，它们的正浮雕得以生存。在晚泥盆世（Frasnian）时期，Pillara石灰岩的相沉积在该浮雕周围。泥盆纪大堡礁的一部分具有线性礁石边缘，其走向与莫万比尼群岛的外部古大陆平行。一个更加庇护的海峡将金伯利街区的内岛与克拉通泥盆纪大陆隔开。克拉通散发出大的扇形三角洲，而奥斯卡山脉中较大的一个古陆上的一个流域则有一个小的滩涂三角洲。今天，该岛由从前泥盆纪，石炭纪和二叠纪地层的掩盖下挖出的局部地形来表达。泥盆纪浅水三角洲不整合地依托在倾斜的元古代的橄榄石上，并结合了在河流到岸面条件下积累的丰富的橄榄石碎片。一些石英岩卵石和热液石英是从超过一公里之外的来源获得的。三角洲沉积物中稀有的腹足动物和间质多孔碎片从邻近的礁石边缘被擦掉。暴露的浅滩水三角洲中由碎屑支撑的砾岩在距离内礁边缘130 m至15 m以内的位置绘图，并在陡倾的千枚石附近暴露。在三角洲顶面相的不整合面之上，形成了一个连续的连续碎屑和碳酸盐副序列的序列，厚度为31.5m。总体演替表示与三角洲相侵蚀有关的相对海平面的小幅下降，以及以逆序顺序堆积模式为特征的海侵。演替过程从富含硅质碎屑的海岸面转移到潮间带的远端后礁相，最后以潮下带，硅质贫瘠的近端礁相结束。该研究表明，在由石英岩高地和千枚石低地为主的岛屿系统中，沉积循环的变化是如何受到局部古地理约束的影响的。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号