Major, trace, rare earth elements and ¹³C isotope results of sediments collected up to the depth of 150 m below ground level (m bgl) have been interpreted in relation to the provenance, weathering and deposition conditions of a multi layered sedimentary formation of Pondicherry region located in East Coast of India. The samples fall in the coarse to medium grain size range (mean Mz: 0.29–1.32) and the sorting values (mean SD: 0.29–1.04) mostly infer very well sorted nature of sediments. Skewness (mean Ski: 0.09-0.99) shows the domination of very fine skew while the kurtosis (mean K_G: 0.76–7.73) shows sediments from extremely lepto kurtic to platy kurtic nature. Micro-structural studies infer that sediments are derived from multiple sources and transported towards the littoral zone through the fluvial processes. Relatively depleted elemental concentrations with respect to upper continental crust (UCC) (elemental ratios < 1) are noticed in most of the sediments suggesting contribution of the weathered source rocks. Chondrite normalized distributions of the selected rare earth elements show uniform trends characterized by light rare earth element enrichment and heavy rare earth element depletion, which is a typical pattern of UCC exposed to weathering and erosion. Elemental ratios such as La/Sc (2.06–6.64), Th/Sc (0.66–4.13), Th/Cr (0.06-0.26) and Th/Co (0.46–1.54) and ternary plots (La-Th-Sc, Th-Hf-Co) indicate the contribution of felsic rocks that are inherently heterogeneous in nature. Observed positive Eu anomaly in Post Archean Australian Shale (PAAS) normalized patterns indicates contribution of plagioclase minerals. Th/U ratio (2.12–9.57) of the sediments reflects deposition under oxic condition (shallow marine) whereas deeper sediments reveal anoxic condition (deep marine), which is further confirmed by δ¹³C_TIC variations (−11.4 to +5.12‰ vs. VPDB) and Eu analmoly. Cr/Th ratio and total REE content indicate that there is no/negligible input of volcanic ash to these sediments.

已经解释了朋底榭里多层沉积地层的物源，风化和沉积条件，解释了主要，痕量，稀土元素和收集到地下高度（m bgl）以下150 m的沉积物的¹³ C同位素结果地区位于印度东海岸。样品的粒度范围从中到粗（平均Mz：0.29-1.32），分选值（平均SD：0.29-1.04）在很大程度上推断出沉积物的分选性质。偏度（平均滑雪：0.09-0.99）显示出峰度（平均K _G）中非常细的偏斜的控制：0.76–7.73）显示了从极轻快的库尔特人到板状的库尔特人的沉积物。微观结构研究推断出沉积物来自多种来源，并通过河床过程向沿海地带输送。在大多数沉积物中都注意到相对于上陆壳（UCC）相对贫乏的元素浓度（元素比<1），表明风化的烃源岩的贡献。所选稀土元素的球粒陨石归一化分布具有均匀的趋势，其特征是轻稀土元素富集和重稀土元素耗竭，这是UCC暴露于风化和侵蚀的典型模式。元素比率，例如La / Sc（2.06-6.64），Th / Sc（0.66-4.13），Th / Cr（0.06-0.26）和Th / Co（0.46-1.54）和三元图（La-Th-Sc，Th-Hf-Co）表明本质上非均质的长英质岩石的贡献。在原始澳大利亚后页岩（PAAS）归一化模式中观察到的正Eu异常表明斜长石矿物的贡献。沉积物的Th / U比（2.12-9.57）反映了在有氧条件下（浅海）的沉积，而较深的沉积物则显示了缺氧条件（深海），这由δ进一步证实。¹³ C _TIC变化（相对于VPDB为-11.4至+ 5.12‰）和Eu异常。Cr / Th比和总REE含量表明没有/可忽略不计的火山灰输入到这些沉积物中。