کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4691356 1636720 2016 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Continental deformation accommodated by non-rigid passive bookshelf faulting: An example from the Cenozoic tectonic development of northern Tibet
ترجمه فارسی عنوان
تغییر شکل قاره ای با خنثی سازی قفسه کتاب غیر انعطاف پذیر مخلوط شده: یک مثال از توسعه تکتونیکی کنوسیوسی شمال تبت
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی


• We propose a non-rigid passive bookshelf-fault model for deformation in north Tibet.
• Right-lateral shear drives clockwise rotation and left-slip faulting on W–E faults.
• Clockwise rotation of faults occurs against left-slip Altyn Tagh bounding fault.
• Model explains bidirectional decrease in slip and four-quadrant strain pattern.
• Protracted deformation in northern Tibet since Eocene

Collision-induced continental deformation commonly involves complex interactions between strike-slip faulting and off-fault deformation, yet this relationship has rarely been quantified. In northern Tibet, Cenozoic deformation is expressed by the development of the > 1000-km-long east-striking left-slip Kunlun, Qinling, and Haiyuan faults. Each have a maximum slip in the central fault segment exceeding 10s to ~ 100 km but a much smaller slip magnitude (~< 10% of the maximum slip) at their terminations. The along-strike variation of fault offsets and pervasive off-fault deformation create a strain pattern that departs from the expectations of the classic plate-like rigid-body motion and flow-like distributed deformation end-member models for continental tectonics. Here we propose a non-rigid bookshelf-fault model for the Cenozoic tectonic development of northern Tibet. Our model, quantitatively relating discrete left-slip faulting to distributed off-fault deformation during regional clockwise rotation, explains several puzzling features, including the: (1) clockwise rotation of east-striking left-slip faults against the northeast-striking left-slip Altyn Tagh fault along the northwestern margin of the Tibetan Plateau, (2) alternating fault-parallel extension and shortening in the off-fault regions, and (3) eastward-tapering map-view geometries of the Qimen Tagh, Qaidam, and Qilian Shan thrust belts that link with the three major left-slip faults in northern Tibet. We refer to this specific non-rigid bookshelf-fault system as a passive bookshelf-fault system because the rotating bookshelf panels are detached from the rigid bounding domains. As a consequence, the wallrock of the strike-slip faults deforms to accommodate both the clockwise rotation of the left-slip faults and off-fault strain that arises at the fault ends. An important implication of our model is that the style and magnitude of Cenozoic deformation in northern Tibet vary considerably in the east–west direction. Thus, any single north–south cross section and its kinematic reconstruction through the region do not properly quantify the complex deformational processes of plateau formation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Tectonophysics - Volumes 677–678, 23 May 2016, Pages 227–240
نویسندگان
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