کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4689251 1636039 2015 15 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Depositional and erosional architectures of gravelly braid bar formed by a flood in the Abe River, central Japan, inferred from a three-dimensional ground-penetrating radar analysis
ترجمه فارسی عنوان
معماری های رسوبی و فرسایشی نوار کاذب گرانشی تشکیل شده توسط یک سیلاب در رودخانه آبه، مرکزی ژاپن، از تجزیه و تحلیل رادار سه بعدی نفوذ زمین
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی
We conducted a ground-penetrating radar (GPR) survey of gravelly braid bars in the Abe River, central Japan, to clarify the three-dimensional (3D) variations in their depositional facies under various geomorphologic conditions. In September 2011, a ten-year return-period flood in the study area reworked and deposited braid bars. After the flood, we surveyed three bars with different geomorphologies using a GPR system with a 250-MHz antenna and identified seven fundamental radar depositional facies: Inclined reflections (facies Ia and Ib), horizontal to subhorizontal reflections (facies IIa and IIb), discontinuous reflections (facies IIIa and IIIb), and facies assemblage with a large-scale channel-shaped lower boundary (facies IV). Combinations of these facies in\dicate bar formation processes: channel filling, lateral aggradation, and lateral and downstream accretion. In the Abe River, aerial photographs and airborne laser scanning data were obtained before and after the flood. The observed changes of the surface topography are consistent with the subsurface results seen in the GPR sections. This study demonstrated that the erosional and depositional architecture observed among bars with different channel styles was related to river width and represented depositional processes for high-sediment discharge. The quantitative characterizations of the sedimentary architecture will be useful for interpreting gravelly fluvial deposits in the rock record.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Sedimentary Geology - Volume 324, 1 July 2015, Pages 32-46
نویسندگان
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