Bouguer anomaly inversion and hydrocode modeling of the central uplift of the Araguainha impact structure
| Autor: | MARCELLE R. MIYAZAKI, EMILSON P. LEITE, MARCOS A.R. VASCONCELOS, KAI WÜNNEMANN, ALVARO P. CRÓSTA |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: | |
| Zdroj: | Anais da Academia Brasileira de Ciências, Vol 93, Iss suppl 4 (2021) |
| Druh dokumentu: | article |
| ISSN: | 1678-2690 0001-3765 |
| DOI: | 10.1590/0001-3765202120210081 |
| Popis: | Abstract Araguainha is a mid-sized complex impact structure formed in sedimentary and underlying basement rocks of the Paraná Basin, Brazil. The structure has strongly deformed sedimentary strata surrounding a granitic core. The central uplift is a region of high geological complexity, comprising different types of sedimentary, igneous (granite) and metamorphic lithologies, plus breccias and impact melt sheets. New ground gravity data was collected to produce a Bouguer anomaly map and to perform a 3-D inversion in order to obtain a 3-D density model of the central uplift. This 3-D density model is consistent with iSALE numerical modeling results, which shows that the rocks in the innermost portion became brecciated and/or melted after undergoing pressure/temperature peaks. The positive anomaly of Furnas and Ponta Grossa formations associated with the numerical model shows that the central uplift is ~16 km wide. Thus, the granite’s uplift caused the uplift of the entire stratigraphic package, from its Devonian-aged units to the Permian ones, forming a bull’s eye pattern around the granitic core. The results also indicate that Araguainha was formed by a 3 km diameter impactor, and the rocks of the granitic basement rocks were uplifted by ~2 km. |
| Databáze: | Directory of Open Access Journals |
| Externí odkaz: |
|