Early Cretaceous Paleoenvironmental Evolution and Mineral Enrichment Patterns of a Lacustrine System Under Orbital Forcing in the Yin'e Basin

A total of 380 rock specimens were collected at 0.2–0.7 m intervals to span the full 189 m succession of the Bayingebi Formation first member, alongside continuous gamma-ray (GR) well-log records compiled to form depth-based time series for cyclostratigraphic orbital analysis. Sample allocation for multiple laboratory analyses is detailed as follows: 26 samples were prepared for thin-section petrography and scanning electron microscope (SEM) characterization; 71 samples underwent X-ray diffraction (XRD) testing to quantify bulk mineral assemblages; 51 mudstone and marlstone specimens were measured for total organic carbon (TOC), organic carbon isotope (δ¹³C) and nitrogen isotope (δ¹⁵N); 20 organic-rich mudstone samples were subjected to gas chromatography-mass spectrometry (GC-MS) biomarker identification; chromaticity measurements were performed on the remaining 369 rock samples.