کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4733913 | 1357059 | 2007 | 12 صفحه PDF | دانلود رایگان |
Many algorithms assume plane strain to construct, model and restore fault-cored folds. Using mechanical models that allow heterogeneous transport in three dimensions, we explore the distribution and magnitude of out-of-plane transport in plunging fault-cored anticlines and provide guidelines of where plane strain should and should not be applied. We developed a new technique of incrementing infinitesimal elastic strains to produce folds with aspect ratios similar to natural folds. Map views of displacement vectors show that in general, out-of-plane displacement is localized near the lateral fold tips. Cross-sections show that out-of-plane transport is depth dependent with out-of-plane displacement increasing toward the surface. Flexural slip surfaces compartmentalize out-of-plane transport within distinct mechanical units, with the maximum out-of-plane displacement near the tops of mechanical units. Two-dimensional models with additional frictionally slipping bed contacts suggest that freely slipping contacts can approximate the deformation of many frictionally slipping contacts. We show that out-of-plane transport is significant in the simplest non-cylindrical folds, and suggest that complex non-cylindrical structures should not be modeled using plane strain exclusively. We also show that flexural slip surfaces exert a significant control on the magnitude and structural position of out-of-plane transport in our models.
Journal: Journal of Structural Geology - Volume 29, Issue 7, July 2007, Pages 1229–1240