Collaborative Research: Plate Tectonic and Geochemical Evolution of the Young Walvis Ridge and Implications for African Plate Motion Modeling

合作研究：年轻沃尔维斯海岭的板块构造和地球化学演化及其对非洲板块运动模型的影响

基本信息

批准号：
0961450
负责人：
Cornelia Class
金额：
$ 27.2万
依托单位：
Columbia University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-01 至 2016-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0961450&HistoricalAwards=false
关键词：
Collaborative Research Plate Tectonic Geochemical

项目摘要

The cause of the bifurcating tracks of seamounts and seafloor swells in the Walvis Ridge area in the South Atlantic just off South Africa has been a longstanding enigma in Marine Geology and in our understanding of hotspots and the plate tectonic evolution of Africa. This project will go to sea to dredge and analyze rocks from the part of the seafloor to the west of the Walvis Ridge and examine changes from hotspot to diffuse volcanism. The present location of the Walvis hotspot and the reason for its waning volcanic activity over the last 60 Myr will also be determined. Argon trapped in minerals in the collected seafloor volcanic rocks will be used to determine the age progression of the volcano tracks. Rock, major and trace element geochemistry and isotopes will be used to see if the younger rocks in the bifurcated tracks can be linked to the older Walvis Ridge. Multibeam bathymetric mapping and a map of seafloor magnetics will also be generated to examine structural trends and plate tectonic motions of this part of the ocean floor. Broader impacts of the work include international collaboration with a complementary German effort that is studying the older part of the Walvis Ridge, K-12 teacher and graduate and undergraduate student training, and support of a PI whose gender is under-represented in the sciences.

南非附近的南大西洋鲸湾海脊地区的海山和海底隆起分叉轨迹的原因一直是海洋地质学以及我们对非洲热点和板块构造演化的理解中的一个长期谜团。该项目将出海疏浚和分析鲸湾海岭以西部分海底的岩石，并研究从热点到扩散火山活动的变化。鲸湾港热点目前的位置以及过去 60 马来西亚林吉特火山活动减弱的原因也将被确定。收集到的海底火山岩中矿物质中的氩将用于确定火山轨迹的年龄进程。岩石、主量元素和微量元素地球化学以及同位素将用于查看分叉轨道中较年轻的岩石是否可以与较古老的沃尔维斯海脊联系起来。还将生成多波束测深测绘和海底磁力图，以检查这部分海底的结构趋势和板块构造运动。这项工作的更广泛影响包括与德国研究沃尔维斯海岭较旧部分的互补性国际合作、K-12 教师、研究生和本科生培训，以及对性别在科学领域代表性不足的 PI 的支持。