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

The samples cover the entire first member of the Bayingebi Formation (total thickness: 189 m). Specific grouping: 26 samples were prepared as thin sections for microscopic and scanning electron microscope (SEM) observations; 71 samples were analyzed for mineral composition using X-ray diffraction (XRD); 51 mudstone and marlstone samples were selected for determinations of total organic carbon (TOC), organic carbon isotope (δ¹³C), and nitrogen isotope (δ¹⁵N); while 20 high-organic-content mudstone samples were used for biomarker analysis via gas chromatography-mass spectrometry (GC-MS); and 369 samples were subjected to chromaticity.