Scientists use proxies to reconstruct past climates and environments, which aids in our understanding of current global climate change and future regional shifts. Speleothems, or cave deposits, are particularly useful when studying climate patterns in tropical regions, as other proxies are limited to polar and temperate regions. Here we used high precision U/Th dating and analyzed δ18O and δ13C values from two speleothems obtained from Pacupahuain and Huagapo Caves, located in the eastern Peruvian Andes. We constructed an age model for speleothem 22-1 using 4 U/Th samples, and found an age range from 56956 ± 206 to 69474 ± 443 years before present. Speleothem 22-21 uses 2 samples and has an age range from 48130 ± 166 to 61981 ± 167 years before present, though we only collected data from a portion of this period. Combined, 22-1 and 22-21 cover part of MIS (Marine Isotope Stage) 3 and MIS 4 (approximately 47,000-71,000 years before present). We compare these to other speleothem and ice core records to look at the timing and relationships of climate events and South American Summer Monsoon patterns. Heinrich event 6 (associated with cooling), and Dansgaard/Oeschger events (rapid warming followed by gradual cooling) are significant climate events identified during this time period and are expressed in our isotopic speleothem record to varying degrees. Both records track solar insolation. 22-1 overlaps with previous Union College isotopic speleothem records and extends the record by about 6000 years. 22-21 bridges the gap between Kanner et al. (2012) and Union College’s isotopic speleothem records.
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