Abstract The study of the paleogeographic landscapes of South China can contribute to understanding its paleo-position within supercontinents. We conducted a combined study of the Nanhuan-Sinian sedimentary records from the southeastern margin of the Yangtze Block (SMYB) in South China. The results reveal the following. (1) 18 datasets from directional sedimentary structures in the strata of the northern and southern SMYB indicate that the siliciclasts were transported towards the SE-SSE and the NWW-NW-NNW-NNE-NE, respectively. (2) 1670 analyses of 18 zircon samples collected from or near the directional structures have concordant U-Pb ages of 3243–563 Ma. 15 detrital zircon samples have a major peak within the range of 850–730 Ma, and 7 detrital zircon samples have eHf(t) values ranging from − 38.7 to + 13.7, and two-stage modal ages of 4.1–0.9 Ga. These new data reveal three important paleogeographic features of eastern South China during the late Tonian to Ediacaran, as follows. (a) The SMYB was a sedimentary basin (called the “Zhe-Gan-Wan Basin”) with opposing paleotopographic dips on two sides. Its northern part was mainly inclined to the SW-S-SE and belonged to the foreslope of the eastern Yangtze Platform. Conversely, its southern part was mainly inclined to the NW-N-NE and was the submerged part of the eroded area in the eastern Cathaysia Block (ECB) extending to the north. (b) The eroded area (called “Zhe-Min Land”) was probably located within the northeastern ECB and was surrounded by depositional areas on at least three sides. The ECB was likely connected to a Grenville-age orogen in the south direction. (c) The paleogeographic landscape configuration of eastern South China may have comprised five domains, from north to south: the eastern Yangtze Platform, the Zhe-Gan-Wan Basin, the Zhe-Min Land in the northeastern ECB, the Gan-Min-Zhe Basin, and a Grenville-age orogen. According to the landscape configuration, during the supercontinental cycles from Rodinia to Gondwana, the Cathaysia Block was likely located on the margin of the supercontinents, close to North India, West Australia, and East Antarctica.

中文翻译：

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晚新元古代华南东部景观构型：扬子地块东南缘沉积指数和锆石U-Pb-Hf同位素的新约束

摘要 研究华南古地理景观有助于了解其在超大陆中的古位置。我们对华南扬子地块东南缘（SMYB）的南环-震旦纪沉积记录进行了综合研究。结果表明如下。(1) SMYB 北部和南部地层定向沉积构造的 18 个数据集表明，硅质碎屑分别向 SE-SSE 和 NWW-NW-NNW-NNE-NE 运移。(2) 1670 次对从定向构造或定向构造附近采集的 18 个锆石样品的分析具有 3243-563 Ma 的一致 U-Pb 年龄。15 个碎屑锆石样品的主峰在 850-730 Ma 范围内，7 个碎屑锆石样品的 eHf(t) 值范围从 - 38.7 到 + 13.7，两阶段模态年龄为 4.1-0。9 Ga. 这些新资料揭示了托尼阶晚期至埃迪卡拉纪华南东部三个重要的古地理特征，如下所示。(a) SMYB 是一个沉积盆地（称为“浙-赣-湾盆地”），两侧古地形倾角相对。其北部主要向西南—东南—东南倾斜，属东部扬子地台前坡。反之，其南部主要向NW-N-NE倾斜，是华夏地块东部（ECB）侵蚀区向北延伸的淹没部分。(b) 侵蚀区（称为“浙闽地”）可能位于欧洲央行东北部，至少在三侧被沉积区包围。欧洲央行很可能与南部的格伦维尔时代造山带相连。(c) 华南东部古地理景观格局从北向南可能包括五个域：扬子地台东部、浙赣湾盆地、欧洲央行东北部浙闽地、赣闽-浙盆地和格伦维尔时代造山带。根据地貌配置，在罗迪尼亚至冈瓦纳的超大陆旋回期间，华夏地块很可能位于超大陆边缘，靠近北印度、西澳大利亚和东南极洲。