Presented are analytical data from lacustrine sediment cores, retrieved from Lake Nam Co (Tibetan Plateau). The sediment core is a composite of one gravity core, taken with a Rumohr-Meischner gravity corer (63 mm diameter) and a piston core, retrieved using an uwitec piston coring system (http://www.uwitec.at; 90 mm diameter). The composite core labelled comprises a total length of 10.378 m. The cores were obtained at N 30.737417, E 090.790333 at a water depth of 93 m on 2008-09-15. The purpose of obtaining this sediment core was to establish a high-resolution record of climate (monsoonal) and environmental change using multiple proxy data. The dataset comprises analytical data based on sedimentological, inorganic geochemical, mineralogical and isotope-geochemical methods. Specifically: sediment water content & density; magnetic susceptibility; particel size data; quantitative inorganic geochemical data (ICP-OES aqua regia and HCL digestions); semi-quantitative XRF elemental data; carbon, nitrogen, sulfur contents; qualitative mineralogical data; bulk sediment stable carbon and oxygen isotope data.

Granulometric data were measured at 1-cm intervals using a laser diffraction technique with two different laser diffraction particle size analyzers, both using the Fraunhofer optical model for calculation. For the upper 43 cm a LS 13 320 (Beckman Coulter, Danvers, MA, USA) was used, whereas for the remaining part of the record a S3500 (Microtrac, Meerbusch, Germany) was applied. Sample pre-processing comprised treatment with H2O2 (15% p.A., 30%p.A.) to remove organic matter and subsequently with HCl (15% p.A.) for the removal of carbonates. For better dispersion 5 ml Sodiumpyrophosphate (Na2HPO4 • H2O) were added and the samples were shaken for 12 h using an overhead shaker.