Deciphering the Dynamics of Continental Deformation in the Arabia-Eurasia Collision Zone

破译阿拉伯-欧亚大陆碰撞带的大陆变形动力学

• 批准号: 0609730
• 负责人: Robert Reilinger
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-15 至 2010-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0609730&HistoricalAwards=false
• 关键词: Deciphering; Dynamics; Continental; Deformation; Arabia

Scientists from the Massachusetts Institute of Technology in collaboration with scientists from Turkmenistan, Azerbaijan, and France are carrying out a GPS investigation in the Caspian Sea region in order to determine the motion of the South Caspian Basin. The plate motion of this portion of the Arabian-Eurasian collision zone is poorly known yet key to understanding the active deformation with the collision zone. Existing data indicate that motions of the westward moving, counter-clockwise rotating Anatolia plate and the counter-clockwise rotating Lesser Caucasus-East Turkey Plateau are inconsistent with current models. This study is exploring the idea that processes associated with subduction of the African lithosphere are fundamentally responsible for the observed motion of Anatolia and the Lesser Caucasus-East Turkey Plateau. Specifically, two hypotheses are being tested: 1) A north-dipping slab is actively sinking beneath the Greater Caucasus, pulling the Lesser Caucasus-East Turkey Plateau northward; 2) The northward motion of the west side of the Lesser Caucasus-East Turkey Plateau is retarded by the rigid oceanic lithosphere of the East Black Sea, while the east side is dragged northward by the northward translating South Caspian block. A network of survey and continuous GPS instruments is being deployed in Turkmenistan and Azerbaijan for four years in order constrain the plate motions in this region.Results from this project will provide a complete kinematic picture of active deformation within the Arabia-Eurasia collision zone and allow determination of the character of strain accumulation along the South Caspian boundary faults, including faults along the west side of the Sea, the Baku-Ashkhabad seismic zone, and the fault systems along the SouthCaspian (Elborz Mountains). This new information will lead to advances in understanding the processes of early continental collision, the consumption of isolated ocean lithosphere within continental collision zones, and the factors that influence the initiation of subduction, slab pull, and lithospheric delamination. A new GPS network will be established and a significant international collaboration will be initiated and will involve training of Turkmenistan and Azerbaijan scientists in GPS techniques and analysis. This project is supported by the Tectonics Program in the Earth Sciences Division and the Europe and Eurasia Program in the Office of International Science and Engineering.

来自马萨诸塞州理工学院的科学家与来自土库曼斯坦、阿塞拜疆和法国的科学家合作，正在里海地区进行全球定位系统调查，以确定南里海盆地的运动。阿拉伯-欧亚碰撞带这一部分的板块运动知之甚少，但对理解碰撞带的活动变形至关重要。现有的资料表明，向西移动，逆时针旋转的安纳托利亚板块和逆时针旋转的小高加索-东土耳其高原的运动与目前的模式不一致。这项研究正在探索的想法，与俯冲的非洲岩石圈的过程是从根本上负责所观察到的运动的安纳托利亚和小高加索-东土耳其高原。具体而言，有两个假设正在测试：1）北倾板块正在大高加索地区下方积极下沉，将小高加索-东土耳其高原向北拉; 2）小高加索-东土耳其高原西侧的向北运动受到东黑海刚性海洋岩石圈的阻碍，而东侧则被向北平移的南里海块体向北拉。在土库曼斯坦和阿塞拜疆部署了一个为期四年的测量和连续全球定位系统仪器网络，以限制该地区的板块运动，该项目的结果将提供阿拉伯-欧亚碰撞带内活动变形的完整运动学图像，并可确定南里海边界断层沿着的应变积累特征，包括里海西侧沿着的断层，巴库-阿什哈巴德地震带和沿着南里海（埃尔博尔兹山脉）的断层系统。这些新的信息将导致在理解早期大陆碰撞的过程中，大陆碰撞带内孤立的海洋岩石圈的消耗，以及影响俯冲，板片拉，岩石圈拆沉的开始的因素的进步。将建立一个新的全球定位系统网络，并将开展重要的国际合作，其中包括对土库曼斯坦和阿塞拜疆科学家进行全球定位系统技术和分析方面的培训。该项目得到了地球科学部构造项目和国际科学与工程办公室欧洲和欧亚项目的支持。