{"title":"The slab failure in Central Java (Indonesia): New insight into its tectonic setting and origin","authors":"","doi":"10.1016/j.sesci.2024.100199","DOIUrl":null,"url":null,"abstract":"<div><p>The geochemical and tectonic characteristics of volcanic formations in Central Java, specifically the Sumbing-Slamet volcanics, were investigated to understand the processes associated with slab failure in the region. Through comprehensive geochemical analysis and comparison with other volcanic formations, insights into the magmatic evolution and tectonic settings of the Sumbing-Slamet volcanics were gained. The findings support the hypothesis of slab tearing beneath Central Java, as evidenced by distinct geochemical signatures and magmatic interactions observed in the Sumbing-Slamet volcanics. Geochemical data reveal medium to high potassium content (K<sub>2</sub>O = 0.77–2.32%), low Nb/Y (<0.6561), low TiO<sub>2</sub> relative to Al<sub>2</sub>O<sub>3</sub> [TiO<sub>2</sub> < (−1.1610 + 0.1935 × Al<sub>2</sub>O<sub>3</sub>)], Th/La >0.2, as well as a wide range of Nb/La and Nb/Zr (0.14–0.89 and 0.0304–0.0744, respectively), notable depletions in high-field strength elements (HFSE; such as Nb, Ti), low to high Ta-anomaly (δTa = 0.21–1.03), and whole-rock isotopes of <sup>87</sup>Sr/<sup>86</sup>Sr (0.704458–0.705800) and <sup>143</sup>Nd/<sup>144</sup>Nd (0.513059–0.512766) demonstrate that they were formed from active continental margin (ACM) tectonics involving subducted sediment input. These magmatic processes likely resulted from the mixing of lithospheric and asthenospheric mantle sources due to slab failure in the northern part of Central Java. The research contributes to strengthening the geophysical view regarding the existence of slab tearing in Central Java, understanding the dynamic geological processes occurring in subduction zones, and emphasizing the importance of interdisciplinary approaches in studying such phenomena.</p></div>","PeriodicalId":54172,"journal":{"name":"Solid Earth Sciences","volume":null,"pages":null},"PeriodicalIF":2.0000,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451912X24000370/pdfft?md5=b60d2415e7471906eb6608946c006767&pid=1-s2.0-S2451912X24000370-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Solid Earth Sciences","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2451912X24000370","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
The geochemical and tectonic characteristics of volcanic formations in Central Java, specifically the Sumbing-Slamet volcanics, were investigated to understand the processes associated with slab failure in the region. Through comprehensive geochemical analysis and comparison with other volcanic formations, insights into the magmatic evolution and tectonic settings of the Sumbing-Slamet volcanics were gained. The findings support the hypothesis of slab tearing beneath Central Java, as evidenced by distinct geochemical signatures and magmatic interactions observed in the Sumbing-Slamet volcanics. Geochemical data reveal medium to high potassium content (K2O = 0.77–2.32%), low Nb/Y (<0.6561), low TiO2 relative to Al2O3 [TiO2 < (−1.1610 + 0.1935 × Al2O3)], Th/La >0.2, as well as a wide range of Nb/La and Nb/Zr (0.14–0.89 and 0.0304–0.0744, respectively), notable depletions in high-field strength elements (HFSE; such as Nb, Ti), low to high Ta-anomaly (δTa = 0.21–1.03), and whole-rock isotopes of 87Sr/86Sr (0.704458–0.705800) and 143Nd/144Nd (0.513059–0.512766) demonstrate that they were formed from active continental margin (ACM) tectonics involving subducted sediment input. These magmatic processes likely resulted from the mixing of lithospheric and asthenospheric mantle sources due to slab failure in the northern part of Central Java. The research contributes to strengthening the geophysical view regarding the existence of slab tearing in Central Java, understanding the dynamic geological processes occurring in subduction zones, and emphasizing the importance of interdisciplinary approaches in studying such phenomena.