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The stable isotopic composition of soil-formed carbonate, and bulk geochemistry of preserved soil matrix, can provide regionally constrained records of hydroclimatic change throughout deep-time. The SK cores, spanning over 10 km of sediment drilled from the Songliao Basin in Northeast China, represent near continuous terrestrial deposition across the late Jurassic to early Paleogene. In this study we analyze SK-1n paleosol core samples spanning late Maastrichtian to early Danian to interpret the regional hydroclimate response to global climate change, concurrent with Deccan Traps volcanism and the Chicxulub impact. Building on numerous paleosol carbonate datasets from the Sifangtai and Mingshui formations, we present ~40 new carbonate clumped isotope measurements at ca. 10 – 20 kyr resolution between 66.3 to 65.5 Ma. We produce a new kernel-smoothed temperature record and estimate the δ18O of soil porewater (δ18Opw), and δ13C of soil CO2 (δ13Cs) from new and previously published datasets. Molecular weathering ratios, derived from bulk geochemistry, are used to reconstruct weathering (CIA-K), clay formation (Al/Si), soil drainage (Ba/Sr), and calculate mean annual precipitation (MAP) via established transfer functions. Preliminary results suggest elevated K-Pg boundary temperatures, averaging ~30 °C, that decline by ~10 °C over the following 500 kyr. Post-impact cooling may contribute to a negative δ18Ocarb excursion (-2.5‰) at ~65.8 Ma. Further, stable subhumid MAP (~1100 mm/yr) across the dataset suggests negligible amount effect influence. Mean δ18Opw (-6.9‰) is largely stable, and does not reflect regional monsoon seasonality. Instead, stable δ18Opw indicates a consistent moisture source, a potential persistent seasonal bias in carbonate formation. Binning all compiled δ18Opw by soil profile depth reveals statistically significant enrichment in the upper 60 cm of soil profiles, and accounts for variability in the δ18Opw (σ = 1.16‰). Soil respiration, modeled from δ13Cs, increases from ca. 700 to 2000 gC/m2/year across the K-Pg boundary, indicating increased productivity despite declining pCO2 and available phosphorus. Future work will expand the temporal range of isotopic measurements (~72 to 65 Ma) and contextualize our latest Cretaceous results within a spatial framework across Asia.