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Reflectance spectroscopy is rapid, inexpensive, and non-destructive and can provide important information about the mineralogy of rocks and sediments. We measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau, with the aim of developing a rapid methodology for detecting paleoclimatic changes. We obtained visible/near-infrared (VNIR) and short-wave infrared (SWIR) spectroscopy data from the red clay in the Jianzha Basin, and analyzed their relationship with independent paleoclimatic records, including mineral contents and environmental magnetic parameters. The results show that the VNIR parameters, including D500, D900, R500, and R900 (where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm, respectively) are temperature-sensitive and correlated with the magnetic susceptibility, frequency-dependent magnetic susceptibility, and the marine δ18O record. The results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital timescales. SWIR parameters, such as AS1400, D1400/D1900 and D1900 (where AS represents the asymmetry of the absorption peaks around 1400 nm), are correlated with the illite and montmorillonite content, and they are sensitive to the weathering intensity. The spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at ∼8.5 Ma and global climatic cooling at ∼7.2 Ma, and thus they are applicable as both regional and global paleoenvironmental indicators. [ABSTRACT FROM AUTHOR]

Jianzha Basin is located in the northeastern Tibetan Plateau (NETP) and contains a thick sequence of Cenozoic sediments that are an archive of information about the growth of the Tibetan Plateau and the evolution of the arid environment of the interior of Asia. Here, we present magnetostratigraphic and palaeoenvironmental records from a 361‐m‐thick sequence of Late Cenozoic eolian Red Clay and intercalated fluviolacustrine deposits in the Jianzha Basin. The magnetostratigraphic results show that the sediments have recorded a continuous geomagnetic polarity sequence from C5r.3r to C3r, spanning the interval from 11.8 to 5.8 Ma in the Late Miocene. There are two intervals of rapidly fluctuating sedimentation rates between ~10 and ~6 Ma, which we interpret as a response to a series of uplifts and expansions to the north and to the east in the NETP. The fluctuations in Rb/Sr ratio and magnetic susceptibility before ~8.57 Ma reflect intensified East Asian summer monsoon (EASM) precipitation which resulted from the growth of the NETP. From ~8.57 to ~7.21 Ma, the EASM was impacted by global cooling and ice build‐up in the Northern Hemisphere in addition to the uplift of the Tibetan Plateau (TP) in the Late Miocene. From ~8.57 to ~7.21 Ma, there is a lack of coherency between the fluctuations in MS and Rb/Sr ratio; however, subsequently, there is significant coherency between the Rb/Sr ratio and the deep‐sea oxygen isotope record present. This suggests that from ~8.57 Ma, the eolian Red Clay sediments in the Jianzha Basin were significantly affected by the addition of dust derived from the deforming and uplifting areas of the TP. [ABSTRACT FROM AUTHOR]