中生代阿尔卑斯山面积沉积,这是过去度板运动的结果
Giovanni Muttoni1, Elisabetta Erba, Dennis V Kent
1Department of Earth Sciences, University of Milan, via Mangiagalli 34, I-20133 Milan, Italy. giovanni.muttoni1@unimi.it
Nature
|March 4, 2005
概括
潘加伊亚 (Pangea) 是一个大陆.
科学领域:
- 地质地质地质地质地质地
- 古海洋学是古海洋学.
- 板块构造学是一种板块构造学.
背景情况:
- 阿尔卑斯山-地中海地区经历了庞盖亚碎片化和大西洋开放后沉积模式的显著变化.
- 沉积面从浅水转移到浅水,包括石灰岩和放射性桃,在罗纪-白纪期间.
- 以前对这些面积变化的解释主要集中在碳酸盐补偿深度 (CCD) 的垂直变化上.
研究的目的:
- 为在伦巴第亚盆地观察到的面层 (石灰石-放射性石-石灰石) 的三分化提出另一种解释.
- 将水平板运动纳入解释放射性岩沉积的模型中.
- 为地中海和中东地区的放射性岩石起源提供一个新的构造模型.
主要方法:
- 在意大利伦巴第亚盆地收集和分析罗-罗时期的古磁样本.
- 在更广泛的古地理背景下分析古度数据.
- 开发一个整合水平板块运动的构造模型.
主要成果:
- 古磁数据表明,伦巴多盆地向近赤道上游区域漂移,然后远离该区域.
- 这种运动被认为是观察到的面状变化的主要驱动因素,特别是放射性的沉积.
- 该研究通过引入水平板运动组件来挑战纯垂直CCD变化模型.
结论:
- 伦巴迪亚盆地的三分化最好通过盆地的相对于赤道上游区域的漂移来解释.
- 水平板块运动是了解罗纪期间放射性岩沉积的关键因素.
- 该模型为整个地中海和中东的罗纪放射性岩分布提供了统一的解释.
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