Glass Microbeads in Analog Models of Thrust Wedges
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 character...
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| Format: | Article |
| Language: | English |
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Academia Brasileira de Ciências
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| Series: | Anais da Academia Brasileira de Ciências |
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| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000100073&lng=en&tlng=en |
| _version_ | 1818028842459070464 |
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| author | TAYNARA D'ANGELO CAROLINE J.S. GOMES |
| author_facet | TAYNARA D'ANGELO CAROLINE J.S. GOMES |
| author_sort | TAYNARA D'ANGELO |
| collection | DOAJ |
| description | 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. |
| first_indexed | 2024-12-10T05:10:13Z |
| format | Article |
| id | doaj.art-f1345880372b4940aa29f5c9798571f7 |
| institution | Directory Open Access Journal |
| issn | 1678-2690 |
| language | English |
| last_indexed | 2024-12-10T05:10:13Z |
| publisher | Academia Brasileira de Ciências |
| record_format | Article |
| series | Anais da Academia Brasileira de Ciências |
| spelling | doaj.art-f1345880372b4940aa29f5c9798571f72022-12-22T02:01:07ZengAcademia Brasileira de CiênciasAnais da Academia Brasileira de Ciências1678-2690891738910.1590/0001-3765201720160291S0001-37652017000100073Glass Microbeads in Analog Models of Thrust WedgesTAYNARA D'ANGELOCAROLINE J.S. GOMESABSTRACT 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.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000100073&lng=en&tlng=encompressional deformation modelssandmicrobeadsphysical and frictional characterizations. |
| spellingShingle | TAYNARA D'ANGELO CAROLINE J.S. GOMES Glass Microbeads in Analog Models of Thrust Wedges Anais da Academia Brasileira de Ciências compressional deformation models sand microbeads physical and frictional characterizations. |
| title | Glass Microbeads in Analog Models of Thrust Wedges |
| title_full | Glass Microbeads in Analog Models of Thrust Wedges |
| title_fullStr | Glass Microbeads in Analog Models of Thrust Wedges |
| title_full_unstemmed | Glass Microbeads in Analog Models of Thrust Wedges |
| title_short | Glass Microbeads in Analog Models of Thrust Wedges |
| title_sort | glass microbeads in analog models of thrust wedges |
| topic | compressional deformation models sand microbeads physical and frictional characterizations. |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000100073&lng=en&tlng=en |
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