Are systematic variations in thrust belt style related to plate boundary processes? (The western Alps versus the Carpathians)
Are systematic variations in thrust belt style related to plate boundary processes? (The western Alps versus the Carpathians)
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冲断带类型的系统变化与板块边界过程有关吗？
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
B. Burchfiel
中科院分区：
文献类型：
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作者：
L. Royden;B. Burchfiel
在地中海地区，西阿尔卑斯山和喀尔巴阡山脉西向东的新生代变形导致了两种不同风格的前陆褶皱和冲断带。两个带之间最显着的区别是存在（喀尔巴阡山脉）或不存在（西阿尔卑斯山）同期弧后伸展，但在结构、地形和变质作用方面也存在其他重要差异。这些冲断带样式的差异主要是在冲断带演化的最后阶段形成的，似乎反映了新生代中晚期西阿尔卑斯山和喀尔巴阡山脉构造环境的根本差异。特别是，它们似乎是收敛的结果，在第一种情况下主要由主要板块运动驱动，在第二种情况下仅由小岩石圈片或碎片的局部运动驱动。我们认为，这两个山带形成的结构样式可能有助于识别世界其他地方在类似构造环境中演化的山带。在这方面，西阿尔卑斯山和喀尔巴阡山脉可以被视为两种不同类型的前陆褶皱冲断带的典型例子（或者更准确地说，是广泛的前陆褶皱冲断带类型中的端元例子）。我们认为，大陆俯冲带和造山带可以大致分为与该带相邻的没有显示出重大弧后伸展变形的部分（西阿尔卑斯山）和在逆冲作用同时表现出弧后伸展的部分（喀尔巴阡山脉）。前者出现在板块整体收敛速度超过俯冲速度的地区，通常表现为结晶基底广泛参与逆冲、地表高品位变质岩出露、地形海拔高、侵蚀量大（数十公里）。后者发现于俯冲速率超过整体板块汇聚速率的地区，通常以冲断带为代表，几乎没有结晶基底参与逆冲，低品位甚至无变质作用，地形海拔低，侵蚀很少，在某些情况下，还存在异常深的前深盆地系统。
Within the Mediterranean region, Cenozoic deformation of the Western Alps and the West to East Carpathians has resulted in two different styles of foreland fold and thrust belt. The most prominent difference between the two belts is the presence (Carpathians) or absence (Western Alps) of contemporaneous back-arc extension, but other important differences in structure, topography and metamorphism also exist. These differences in thrust belt style developed mainly during the final stages of thrust belt evolution and appear to reflect fundamental differences in the tectonic settings of the Western Alps and the Carpathians in middle and late Cenozoic time. In particular, they appear to be the result of convergence that is in the first case driven primarily by major plate motions and in the second case only by local motions of small lithospheric flakes or fragments. We suggest that the structural styles developed in these two mountain belts may be useful in identifying mountain belts that have evolved in similar tectonic settings elsewhere in the world. In this respect, the Western Alps and the Carpathians can be regarded as typical examples of two different styles of foreland fold and thrust belt (or more properly as end-member examples within a broad spectrum of foreland fold and thrust belt styles). We propose that continental subduction zones and orogenic belts can be loosely divided into segments that show no major back-arc extensional deformation adjacent to the belt (the Western Alps) and segments that exhibit back-arc extension contemporaneously with thrusting (the Carpathians). The former are found in areas where the rate of overall plate convergence exceeds the rate of subduction, and are commonly typified by extensive involvement of crystalline basement in thrusting, exposure of high grade metamorphic rocks at the surface, high topographic elevation, and large amounts of erosion (tens of kilometers). The latter are found in areas where the rate of subduction exceeds the rate of overall plate convergence and are commonly typified by thrust belts with little to no involvement of crystalline basement in thrusting, low grade to no metamorphism, low topographic elevation, little erosion and, in some instances, an anomalously deep foredeep basin system.