印度迪布鲁加大学Yadav Krishna Gogoi团队分析了印度东北部阿鲁纳恰尔喜马拉雅半岛外冈瓦纳群砂岩的岩石学和地球化学视角：探测物源、构造背景和古环境条件。2025年4月2日出版的《地球化学学报》发表了这项成果。

印度东北阿鲁纳恰尔喜马拉雅山脉的小喜马拉雅层序内，半岛外冈瓦纳岩群岩石以狭窄的斑块暴露。冈瓦纳群砂岩的大部分沉积物来自长英质/酸性到中等火成岩，少量镁铁质来自上大陆地壳（UCC），这得到了基于碎屑矿物定量和砂岩地球化学的各种判别图的支持。

正如石英品种的量化所表明的那样，不能排除次级变质源的输入。这些沉积物被发现来源于克拉通或地盾的内部，以及来自被动和主动边缘环境的再循环台地沉积物。沉积物经历了从干旱到潮湿的气候条件的巨大变化，在低平原到中等丘陵附近遭受了低至中等强度的风化（CIA:63.43；CIW:86.18；WIP：44.84；PIA:75.37；ICV:2.39；C值：0.42；PF:0.49；Sr/Cu:9.23和Rb/Sr:1.68）。此外，氧化还原敏感元素表明沉积物在含氧或富氧条件下沉积（Uau:-2.91；Th/U:7.37；U/Th:0.18；V/Cr:1.71；δU:0.67和Ce/Ce*:0.93）。

附：英文原文

Title: Petrographic and geochemical perspectives on sandstones of the extra-peninsular Gondwana Group from the Arunachal Himalayas, NE India: Probing provenance, tectonic context and paleoenvironmental conditions

Author: Gogoi, Yadav Krishna, Borgohain, Pradip, Bhuyan, Diganta, Bezbaruah, Devojit, Konwar, Garima, Gogoi, Manash Pratim, Bharali, Bubul

Issue&Volume: 2025-04-02

Abstract: The extra-peninsular Gondwana Group rocks are exposed in narrow patches within the Lesser Himalayan sequence of the NE-Arunachal Himalayas, India. The bulk of sediments for the sandstones of the Gondwana Group were derived from felsic/acidic to intermediate igneous rocks, with minor mafic input from the upper continental crust (UCC), as supported by various discrimination diagrams based on quantification of detrital minerals coupled with sandstone geochemistry. The inputs from metamorphic sources in subordinate amounts cannot be ruled out, as indicated by quantification of the quartz varieties. These sediments were found to be sourced from the interior part of a craton or shield and recycled platformal sediments which were derived from both passive and active margin settings. The sediments experienced a wide variance in climatic conditions, from arid to humid, suffering low–moderate-intensity weathering (CIA: 63.43; CIW: 86.18; WIP: 44.84; PIA: 75.37; ICV: 2.39; C-value: 0.42; PF: 0.49; Sr/Cu: 9.23 and Rb/Sr: 1.68) within the vicinity of the low plains to moderate hills. Additionally, redox-sensitive elements indicate the deposition of sediments under oxygenated or oxygen-rich conditions (Uau: 2.91; Th/U: 7.37; U/Th: 0.18; V/Cr: 1.71; δU: 0.67 and Ce/Ce*: 0.93).

DOI: 10.1007/s11631-025-00771-0

Source: https://link.springer.com/article/10.1007/s11631-025-00771-0