Trinil (Java, Indonesia) yielded the type fossils of Homo erectus and the world’s oldest hominin-made engraving. As such, the site is of iconic relevance for paleoanthropology. However, our understanding of its larger geological context is unsatisfactory. Previous sedimentological studies are around 100 years old and their interpretations sometimes contradictory. Moreover, the existing stratigraphic framework is based on regional correlations, which obscure differences in local depositional dynamics. Therefore, a new and more local framework is urgently needed. We carried out a comprehensive geological study of the Trinil area. Using a Digital Elevation Model, we identified seven fluvial terraces. Terrace deposits were described and OSL-dated and fluvial behaviour was reconstructed. The terraces were correlated with terraces of the Kendeng Hills (e.g. the hominin-bearing Ngandong terrace) and date back to the past ∼350 ka. Thus far, most of the Trinil terraces and their deposits had remained unidentified, confounding sedimentological and stratigraphic interpretations. The exposed pre-terrace series has a thickness of ∼230 m. Together with the terraces, it forms a ∼3 Ma record of tectonism, volcanism, climate change and sea-level fluctuations. We subdivided the series into five new and/or revised stratigraphic units, representing different depositional environments: Kalibeng Formation, Padas Malang Formation, Batu Gajah Formation, Trinil Formation and Solo Formation. Special attention was paid to erosional contacts and weathering profiles, forming hiatuses in the depositional series, and offering insight into paleoclimate and base-level change. The Trinil Formation provides a new landscape context of Homo erectus. Between ∼550 and 350 ka, the area was part of a lake basin (Ngawi Lake Basin), separated from the marine base level by a volcanic barrier, under dry, seasonal conditions and a regular supply of volcanic ash. An expanding and retreating lake provided favourable living conditions for hominin populations. After 350 ka, this role was taken over by the perennial Solo River. Landscape reconstructions suggest that the Solo formed by headward erosion and stream piracy, re-connecting the Ngawi Lake Basin to the plains in the west. Our study offers a local framework, but its Pleistocene landscape record has regional significance. Most of all, it forms a much-needed basis for future, detailed studies on the build-up of the hominin site of Trinil, its fossil assemblages and numerical ages.

Trinil（印度尼西亚爪哇省）生产了直立人的化石类型以及世界上最古老的人制雕刻。因此，该地点与古人类学具有标志性的意义。但是，我们对其广阔的地质背景的了解并不令人满意。以前的沉积学研究大约有100年的历史，其解释有时是矛盾的。此外，现有的地层学框架是建立在区域相关性的基础上的，而区域相关性掩盖了局部沉积动力学的差异。因此，迫切需要一个新的，更本地化的框架。我们对特里尼尔地区进行了全面的地质研究。使用数字高程模型，我们确定了七个河流阶地。描述了阶地沉积物，并建立了OSL日期和河流行为。阶地与肯登山的阶地相关（例如 含人参的Ngandong阶地），其历史可追溯至约350 ka。迄今为止，大多数特里尼尔阶地及其沉积物尚未确定，这使沉积学和地层学解释混淆了。裸露的露台前系列的厚度约为230 m。与阶地一起，形成了约3 Ma的构造，火山活动，气候变化和海平面波动记录。我们将该系列划分为五个新的和/或修订的地层单元，分别代表不同的沉积环境：卡里彭组，帕达斯马朗组，黑风加耶组，特里尼尔组和独奏组。特别注意侵蚀接触和风化剖面，在沉积系列中形成了裂隙，并提供了对古气候和基准面变化的洞察力。直立人。在大约550至350 ka之间，该区域是湖泊盆地（Ngawi湖盆地）的一部分，在干燥，季节性条件和定期供应火山灰的情况下，该山脉与火山海底层之间被火山屏障隔开。不断扩大和向后退的湖泊为人族人口提供了有利的生活条件。在350 ka之后，这一角色由常年的独奏河接管。景观重建表明，由向前侵蚀和溪流海盗形成的独奏使Ngawi湖盆地与西部平原重新连接。我们的研究提供了一个局部框架，但其更新世的景观记录具有区域意义。最重要的是，它构成了未来详细研究特里尼尔人形遗址，其化石组合和数字年龄的详细研究的基础。