A new model for the Paleogene motion of Greenland relative to North America: Plate reconstructions of the Davis Strait and Nares Strait regions between Canada and Greenland
A new model for the Paleogene motion of Greenland relative to North America: Plate reconstructions of the Davis Strait and Nares Strait regions between Canada and Greenland
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DOI：
10.1029/2011jb008942
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发表时间：
2012-10
影响因子：
--
通讯作者：
G. Oakey;J. Chalmers
中科院分区：
文献类型：
--
作者：
G. Oakey;J. Chalmers
[1] 已开发出一个格陵兰相对于北美洲的古近纪运动的简化板块运动学模型，为巴芬湾的海洋扩张系统以及北极的戴维斯海峡和内尔斯海峡地区的板内构造发育建模提供了一个新框架。利用从巴芬湾卫星重力数据解译出的扩张中心和断裂带，并结合已发表文献中拉布拉多海的断裂带，计算出格陵兰板块相对于北美洲在始新世C13N到C24N期间的单一欧拉旋转极。针对古新世C25N到C27N部分提出了一个单阶段极，并且发现有必要设置一个短暂阶段极来适应C24N到C25N区间。该运动学模型已被用于重新解释巴芬湾中部已发表的船载磁力剖面，以揭示一个古新世扩张中心以及始新世和古新世洋壳的范围。巴芬湾东北部的航空磁力数据已被用于识别巴芬湾北部的一个新断裂带。给出了结合陆上和海上地质与地球物理测绘对板块边界约束的板块重建。在戴维斯海峡内，古新世洋壳侵位于一个狭长的裂谷中，该裂谷随后沿昂加瓦断层带因始新世约300公里的挤压作用而反转。在内尔斯海峡地区，提出了一种“微板块”情景来解释兰卡斯特海峡裂谷盆地的同时形成以及尤里坎造山带内的复杂变形。
[1] A simplified plate kinematic model for the Paleogene motion of Greenland relative to North America has been developed to provide a new framework for modeling the oceanic spreading system in Baffin Bay and the intraplate tectonic development of the Davis Strait and Nares Strait regions of the Arctic. A single Euler rotation pole was calculated for the C13N to C24N Eocene motion of the Greenland Plate relative to North America using spreading centers and fracture zones interpreted from satellite derived gravity data in Baffin Bay combined with fracture zones in Labrador Sea from published sources. A single stage pole is proposed for the C25N to C27N portion of the Paleocene and a short-lived stage pole was found necessary to accommodate the C24N to C25N interval. This kinematic model has been used to reinterpret published shipborne magnetic profiles in central Baffin Bay to reveal a Paleocene spreading center and limits of both Eocene and Paleocene oceanic crust. Aeromagnetic data over northeastern Baffin Bay have been used to identify a new fracture zone in northern Baffin Bay. Plate reconstructions are presented incorporating constraints on plate boundaries from onshore and offshore geological and geophysical mapping. Within the Davis Strait, Paleocene oceanic crust was emplaced in an elongated rift that was subsequently inverted by approximately 300 km of Eocene transpression along the Ungava Fault Zone. In the Nares Strait Region, a “microplate” scenario is presented to explain the simultaneous formation of the Lancaster Sound Rift Basin and complex deformation within the Eurekan Orogenic Belt.