Collaborative Research: Pre- and Syn-Rift Extension, Magmatism and Segmentation along the Eastern North American Margin

GSTDTAP

项目编号	1654781
	Collaborative Research: Pre- and Syn-Rift Extension, Magmatism and Segmentation along the Eastern North American Margin
	Maria Beatrice Magnani
主持机构	Southern Methodist University
项目开始年	2017
	2017-04-15
项目结束日期	2019-03-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	144035(USD)
国家	美国
语种	英语
英文摘要	The eastern North America margin of the U.S. is a mature continental margin formed by the breakup of the supercontinent Pangaea and the opening of the Atlantic Ocean ~175-140 million years ago. The margin has experienced some of the largest recorded Quaternary offshore slope failures (e.g., the Currituck landslide and Grand Banks landslide and tsunami) within the last 2 million years, and large recent (magnitude 5.9 2011 Mineral, VA) and historic (magnitude 7.3 1886 Charleston, SC) earthquakes. These events highlight the potential hazards as the margin continues to evolve today, millions of years after the cessation of rifting. Using a recently acquired onshore-offshore seismic dataset, this project will delineate crustal and basin structure within the coastal plains and continental shelf of North Carolina and southern Virginia, to understand the processes involved in rift initiation and passive margin evolution. Understanding rift formation and evolution is an active area of research within the hazard community as well as the energy sector, with impacts that relate to many fields such as hazard mitigation, land use planning, local fishing, and tourist economies. The project supports the training of two graduate students, one at the University of New Mexico (a minority serving institution) and the other at Southern Methodist University. This project investigates the relationship between extension, magmatism and margin segmentation in the early stages of western Atlantic rifting using the amphibious active-source seismic dataset collected during the Eastern North American Margin (ENAM) Community Seismic Experiment. Analysis of two margin-normal seismic refraction profiles spanning the coastline from extended continental crust to mature oceanic crust and of one margin-parallel profile along the rupture zone and the East Coast Magnetic Anomaly will constrain the record of early extension onshore, define the continental-oceanic transition and the lateral extent of pre- and syn-rift magma emplacement and margin segmentation. Analysis of 2-D seismic reflection profiles across the continent-ocean transition will delineate along-strike and margin-dip variations of seaward-dipping reflections age and character, of pre- syn- and post-rift sedimentary sequences, and igneous basement character and crustal structure. The data will provide critical information about margin segmentation during rift initiation and evolution and magmatic distribution. The ENAM is a well-preserved, mature rifted margin created during the breakup of the supercontinent Pangea in the Mesozoic that records multiple stages of Paleozoic continental amalgamation, lithospheric breakup and the interaction with the Central Atlantic Magmatic Province (CAMP), one of the largest and most enigmatic igneous provinces worldwide. This project will examine how magmatism is distributed along and across the margin, how it correlates with both pre-existing suture zones and with modern segmentation at mid-oceanic ridges, and whether the margin is overprinted by the voluminous CAMP emplacement.
来源学科分类	Geosciences - Ocean Sciences
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/70971
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Maria Beatrice Magnani.Collaborative Research: Pre- and Syn-Rift Extension, Magmatism and Segmentation along the Eastern North American Margin.2017.