Chemical composition data of various samples from the Ashikule Basin on the Qinghai-Tibet Plateau

This dataset is primarily based on the testing of various samples collected during a field survey conducted in the Ashikule Basin in the northern part of the Qinghai-Tibet Plateau in April 2021. The samples mainly include scattered samples distributed in the basin, stratified water samples taken from a certain depth of two lakes, and sediment core samples, among which the sediment core samples were also segmented into 1-2cm samples.After the water samples were transported back to the laboratory, they were immediately filtered using a 0.45 μm pore size filter membrane to remove suspended matter. The pH values of the water samples were calibrated against the data from a field handheld multi-parameter analyzer (SG-78) using a benchtop pH meter (SD20 HA Kit, Mettler). The chemical composition of all samples was tested at the Analytical Testing Department of the Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. The concentrations of anions (Br-, F-, Cl-) in the water samples were measured using an ion chromatograph (ICS-5000A), while the concentrations of CO32- and HCO3- were determined using potentiometric titration, and SO42- was measured using barium chloride titration. The concentration of K+ in cations was determined using flame atomic absorption spectrometry, while the contents of Ca2+ and Mg2+ were measured using EDTA titration. The concentration of Na+ was calculated based on the ion balance relationship: Na+(meq/L) = (CO32- + HCO3- + SO42- + Cl-) - (K+ + Ca2+ + Mg2+), where the concentrations of each ion are expressed in milliequivalents per liter. The analytical precision for major anions and cations is ±2%. Trace elements Li and B were measured using an inductively coupled plasma optical emission spectrometer (ICP-OES), with a precision better than ±10%The whole-rock trace element testing of volcanic rock samples and lake sediment samples was conducted at the Key Laboratory of Submarine Science, Second Institute of Oceanography, Ministry of Natural Resources. The sample pretreatment involved complete digestion using a mixed acid system of HNO₃-HF-HClO₄, followed by determination using an Elan DRC-e inductively coupled plasma mass spectrometer (ICP-MS). The relative standard deviation (RSD) of the analysis process was less than 3%. The data is presented in tabular form, with various element indicators arranged horizontally and sample numbers arranged vertically. It also includes various comparative data obtained from published materials. The measurement units involved are explained in detail in the table.  Some data are missing, primarily due to elemental contents below the detection limit and inherent omissions in relevant literature.  Data errors are primarily caused by factors such as testing methods and instrument performance, but the data accuracy meets mainstream technical requirements.