The Cenozoic depositional history of central Sundaland is well known from subsurface studies of the numerous basins that litter the region, which record an Eocene to Miocene rift–inversion basin evolution. However, as is common with offshore studies, these often lack the 3D spatial observations and sedimentary provenance data required to link depositional environments, sediment pathways, and tectonic events at scale. The benefits of onshore analogue studies for understanding offshore stratigraphy are well recorded and they are of particular importance in the largely submerged area of Sundaland. Here we provide new facies analysis, sedimentary provenance data, and palaeogeographic histories for Eocene to Pleistocene sediments from Natuna Island, off the northwest coast of Borneo. Natuna Island sits atop the Natuna Arch, a structural high that straddles the East and West Natuna basins. This research records a well-preserved source-to-sink package, including an uplifted granitic basement that eroded into conglomerates and quartz-rich sandstones deposited in deltaic and paralic environments with intermittent volcanism throughout the Cenozoic. U-Pb zircon geochronology, heavy minerals, and light minerals record dominantly local sourcing with periodic influx of more diverse sources during the post-rift basin interlinkage phase (e.g., Peninsular Malaysia and West Borneo). Uplift of the Natuna Arch during two basin inversion events since the Eocene has led to the erosion of the granitic basement into a series of sandstones and overlying siltstones that now form the lowlands of the island (the Raharjapura and Pengadah formations, respectively). These onshore sediments correlate directly in both age and sedimentology with Oligocene to Pliocene successions in the West and East Natuna basins that flank the island (e.g., the Gabus, Arang, and Muda formations). These comprehensive onshore studies provide insights into larger drainage patterns and sediment transport pathways along with the linkage of basins and emergence of land at key intervals.

中文翻译：

---

印度尼西亚纳土纳岛新生代矿床的沉积环境和沉积物源：对巽他兰中部盆地演化的影响


巽他兰中部的新生代沉积历史通过对该地区众多盆地的地下研究而众所周知，这些盆地记录了始新世到中新世裂谷-反转盆地的演化。然而，与近海研究一样，这些研究通常缺乏将沉积环境、沉积路径和大规模构造事件联系起来所需的 3D 空间观测和沉积物源数据。陆上模拟研究对于了解近海地层学的好处已得到充分记录，并且在巽他兰大部分被淹没的地区尤其重要。在这里，我们提供婆罗洲西北海岸纳土纳岛始新世至更新世沉积物的新相分析、沉积物源数据和古地理历史。纳土纳岛坐落在纳土纳拱顶，纳土纳拱是横跨东纳土纳盆地和西纳土纳盆地的一座结构高地。这项研究记录了一个保存完好的源头到汇的组合，包括隆起的花岗岩基底，侵蚀成砾岩和富含石英的砂岩，沉积在三角洲和近海环境中，整个新生代都有间歇性火山活动。 U-Pb锆石地质年代学、重矿物和轻矿物记录了主要是本地来源，并在裂谷后盆地互连阶段（例如马来西亚半岛和西婆罗洲）定期涌入更多样化的来源。自始新世以来的两次盆地反转事件期间纳土纳拱门的隆起导致花岗岩基底被侵蚀成一系列砂岩和上覆粉砂岩，这些砂岩和上覆粉砂岩现在形成了该岛的低地（分别为 Raharjapura 和 Pengadah 地层）。 这些陆上沉积物在年龄和沉积学上与岛屿两侧的纳土纳西部和东部盆地（例如加布斯、阿朗和穆达地层）的渐新世到上新世的序列直接相关。这些全面的陆上研究提供了对更大的排水模式和沉积物输送路径以及盆地的联系和关键间隔土地出现的见解。