Survival Conditions of Folding in Different Depth During Orogenesis-Deformation in Texas Creek and Chester Dome, USA  

作　　者：CAO Hui XU Cuiping 

机构地区：[1]State Key Laboratory for Continental Tectonics and Dynamics, Institute of Geology, Chinese Academy of Geological Sciences [2]School of Earth and Environmental Sciences, James Cook University

出　　处：《Acta Geologica Sinica(English Edition)》2014年第1期103-112,共10页地质学报（英文版）

基　　金：supported in part by grants from National Natural Science Foundation of China (41202153);China Council Scholarship (2013693);MLR, China (201211093);Institute of Geology, CAGS (J1101)

摘　　要：A succession of 5 FIA trends（foliation intersection or inflection axes in porphyroblasts） preserved in high temperature-low pressure regime PreCambrian rocks in the Texas Creek, Arkansas River region reflected by the fold axial plane traces and schistosity data in this region. Similar fold axial plane trace data measured in Palaeozoic rocks in Chester Dome, Vermont, which is high temperature to medium pressure regime, only preserve the effects of the youngest FIAs of the all 5 FIA sets that obtained in this region. The other three FIA sets have no equivalent fold axial planes. This difference from shallow to deeper orogenic regimes reflects decreasing competency at greater pressure with collapse and unfolding of earlier formed folds. The greater overlying load of rocks has tended to flatten all but the very largest early-formed structures, preserving only those folds that were more recently developed.A succession of 5 FIA trends（foliation intersection or inflection axes in porphyroblasts） preserved in high temperature-low pressure regime PreCambrian rocks in the Texas Creek, Arkansas River region reflected by the fold axial plane traces and schistosity data in this region. Similar fold axial plane trace data measured in Palaeozoic rocks in Chester Dome, Vermont, which is high temperature to medium pressure regime, only preserve the effects of the youngest FIAs of the all 5 FIA sets that obtained in this region. The other three FIA sets have no equivalent fold axial planes. This difference from shallow to deeper orogenic regimes reflects decreasing competency at greater pressure with collapse and unfolding of earlier formed folds. The greater overlying load of rocks has tended to flatten all but the very largest early-formed structures, preserving only those folds that were more recently developed.

关 键 词：OROGENESIS fold axial plane foliation intersection or inflection axes gravitational collapse PORPHYROBLAST 

分 类 号：P542[天文地球—构造地质学]