| Journal: | Anais da Academia Brasileira de Ciencias |
| Database: | PERIÓDICA |
| System number: | 000418010 |
| ISSN: | 0001-3765 |
| Authors: | D'Angelo, Taynara1 Gomes, Caroline J.S1 |
| Institutions: | 1Universidade Federal de Ouro Preto, Departamento de Geologia, Ouro Preto, Minas Gerais. Brasil |
| Year: | 2017 |
| Season: | Mar |
| Volumen: | 89 |
| Number: | 1 |
| Pages: | 73-90 |
| Country: | Brasil |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Experimental, aplicado |
| English abstract | Glass microbeads are frequently used in analog physical modeling to simulate weak detachment zones but have been neglected in models of thrust wedges. Microbeads differ from quartz sand in grain shape and in low angle of internal friction. In this study, we compared the structural characteristics of microbeads and sand wedges. To obtain a better picture of their mechanical behavior, we determined the physical and frictional properties of microbeads using polarizing and scanning electron microscopy and ring-shear tests, respectively. We built shortening experiments with different basal frictions and measured the thickness, slope and length of the wedges and also the fault spacings. All the microbeads experiments revealed wedge geometries that were consistent with previous studies that have been performed with sand. However, the deformation features in the microbeads shortened over low to intermediate basal frictions were slightly different. Microbeads produced different fault geometries than sand as well as a different grain flow. In addition, they produced slip on minor faults, which was associated with distributed deformation and gave the microbeads wedges the appearance of disharmonic folds. We concluded that the glass microbeads may be used to simulate relatively competent rocks, like carbonates, which may be characterized by small-scale deformation features |
| Disciplines: | Geociencias |
| Keyword: | Geología, Modelos de deformación por compresión, Arena, Microesferas, Caracterización física |
| Keyword: | Geology, Compressional deformation models, Sand, Microbeads, Physical characterization |
| Full text: | Texto completo (Ver HTML) |
