We present new high-resolution carbonate carbon isotope data (δ¹³C_carb) from four sections in the Yangtze Platform, South China, ranging in age from Tremadocian to early Katian. The data have five distinct characteristics: 1) A prominent δ¹³C_carb increase from −2.79‰ to 0.13‰ at the base of the Ordovician within the Tremadocian Cordylodus angulatus-Rossodus manitouensis Zone. 2) A positive δ¹³C_carb excursion from −2.56‰ to 0.58‰ in the Paltodus deltifer Zone during the late Tremadocian. 3) A gradual increase in δ¹³C_carb from −1.16‰ at the top of the Oepikodus communis Zone to a peak of ~0.74‰ in the Baltoniodus triangularis Zone at the Floian-Dapingian boundary. 4) A moderate rise in δ¹³C_carb from 0.59‰ to 1.24‰ in the middle Darriwilian Dzikodus tablepointensis Zone. 5) A distinct positive δ¹³C_carb excursion from 0.86‰ to 2.32‰ at the base of the Amorphognathus superbus-Hamarodus europaeus Zone during the early Katian. These excursions can be correlated with C-isotopic trends identified in age-equivalent successions in South China, Argentine Precordillera, North America, and Central Sweden, demonstrating their potential for global correlations and providing a composite, high-resolution chemostratigraphic framework for sedimentary records of the Lower-Upper Ordovician in South China. Besides, our data demonstrate a temporal coincidence between the long-term rise in δ¹³C_carb and the Great Ordovician Biodiversification Event, suggesting that enhanced organic matter burial and accompanied climatic cooling and oxygenation may have played an important role in promoting the increases in biodiversity during the Ordovician.

我们提供了来自华南扬子地台四个剖面的新的高分辨率碳酸盐碳同位素数据 (δ ¹³ C _carb )，年龄范围从 Tremadocian 到早期 Katian。数据有五个不同的特征：1)在 Tremadocian Cordylodus angulatus - Rossodus manitouensis带内的奥陶系底部，δ ¹³ C_{碳水化合物}显着增加，从 -2.79‰ 增加到 0.13‰ 。2)晚Tremadocian 期间Paltodus deltifer区的δ ¹³ C_{碳水化合物}正偏移从-2.56‰ 到0.58‰ 。3) δ ¹³ C _carb从顶部的-1.16‰逐渐增加Oepikodus community带在弗洛亚-大坪阶边界的 Baltoniodus triangleis 区达到约 0.74‰的峰值。4) Darriwilian Dzikodus tablepointensis区中部的δ ¹³ C_{碳水化合物}从 0.59‰适度上升至 1.24‰ 。5)在Amorphognathus superbus - Hamarodus europaeus的底部，明显的正 δ ¹³ C_{碳水化合物}偏移从 0.86‰ 到 2.32‰卡提安早期的地带。这些偏移可以与在华南、阿根廷前科迪勒拉、北美和瑞典中部的年龄等效序列中确定的 C 同位素趋势相关联，展示了它们在全球相关性方面的潜力，并为沉积记录提供了一个复合的高分辨率化学地层框架。华南下奥陶统。此外，我们的数据表明 δ ¹³ C_{碳水化合物}的长期上升与奥陶纪生物多样性大事件之间存在时间重合，这表明有机物埋藏的增强和伴随的气候冷却和氧化可能在促进生物多样性的增加方面发挥了重要作用奥陶纪期间。