Description: Here are presented Mulu, Borneo (4°6'N, 114°53'E) Secret Cave stalagmite SC02 d18O and d13C values over Termination 1, published in Buckingham et al. (2022). This study reports a d18O and d13C record for the portion of SC02 104.1 to 182.4 mm distance from top of stalagmite. The d18O record spans the full deglaciation, and reveals for the first time distinct d18O variations connected with the Bølling-Allerød onset and the Younger Dryas event.

Description: Samples for carbon and oxygen isotopic analysis were micromilled at 3.0 and 0.2 mm increments along the main growth axis. Approximately 3000 samples were measured using a semi-automated gas preparation and introduction system (Gasbench II) linked to a Delta V Plus isotope ratio mass spectrometer (both ThermoFisher) at the University of Innsbruck, following the methods of Spötl and Vennemann (2003). Isotope values are reported relative to the Vienna Pee Dee Belemnite (VPDB) reference. Long-term analytical precision is better than 0.1‰ (1σ) for both δ13C and δ18O.

Description: Paleoclimate records from the Middle East are sparse in comparison to other regions. The records as such could be useful to improve our understanding of natural variability in atmospheric circulation patterns. In particular, there are no paleoclimate studies in Iran that span the transition from the Last Glacial Maximum (LGM) to the Holocene based on speleothems. In light of the significant changes in the global climate since the last glacial period (LGM to Early Holocene), it is useful to examine regional climate variability during this time period to gain a better understanding of the climate sensitivity of different areas. In this study we report the first stalagmite records spanning the LGM and the corresponding deglacial transition in southwestern Iran. The sample was collected from Sibaki cave (29֯ 48' 54" N, 51֯ 35' 47" E) in southwestern Zagros, Iran. The cave entrance opens at 1275 m a.s.l. on a NE-facing slope of 1275 m a.s.l. There were no active drips onto SIB-4 when the stalagmite was collected in February 2019.

Description: An interpolated age model with 68% and 95% confidence ranges was produced using OxCal version 4.4 (doi:10.1594/PANGAEA.955839). The age model uses a Poisson process deposition model, with stalagmite vertical growth rate constrained using model inputs k0= 0.1 mm-1 and log10(k/k0) = U (-2, 2) (Bronk Ramsey, 2008, 2009; Bronk Ramsey and Lee, 2013).

Description: Here are presented Mulu, Borneo (4°6'N, 114°53'E) Secret Cave stalagmite SC02 d18O and d13C values over Termination 1, published in Buckingham et al. (2022). U-Th ages were calculated using the initial detrital 230Th/232Th value of 111 ± 41 ppm, which was previously calculated for SC02 based on two isochrons measured in separate stalagmites from Secret Cave in Mulu (Carolin et al., 2013). A Matlab Monte Carlo script was used to calculated the absolute age and age errors associated with each U-Th sample using the 234U and 230Th half lives presented in Cheng et al. (2013). The Poisson-process deposition model feature in OxCal(v4.4) was used to interpolate between the eighteen U/Th ages to produce an age model (Bronk Ramsey, 2008; Bronk Ramsey and Lee, 2013). This study reports a d18O and d13C record for the portion of SC02 104.1 to 182.4 mm distance from top of stalagmite. The d18O record spans the full deglaciation, and reveals for the first time distinct d18O variations connected with the Bølling-Allerød onset and the Younger Dryas event.

Description: U-Th ages were calculated using the initial detrital 230Th/232Th value of 111 ± 41 ppm, which was previously calculated for SC02 based on two isochrons measured in separate stalagmites from Secret Cave in Mulu (Carolin et al., 2013). A Matlab Monte Carlo script was used to calculated the absolute age and age errors associated with each U-Th sample using the 234U and 230Th half lives presented in Cheng et al. (2013). The Poisson-process deposition model feature in OxCal(v4.4) was used to interpolate between the eighteen U/Th ages to produce an age model (Bronk Ramsey, 2008; Bronk Ramsey and Lee, 2013).

Description: A total of 32 230Th ages were measured along the growth axis of SIB-4 stalagmite. 100-200 mg of calcite powder was drilled per sample in a laminar-flow hood following growth lamina. The samples were chemically prepared at the Department of Earth Sciences, University of Oxford. The samples were spiked with a mixed 229Th-236U spike, dissolved in HNO3 and refluxed on a hot-plate overnight for spike-sample equilibration. Chemical separation of U and Th was done following procedures adapted from Edwards et al. (1987). The separated U and Th fractions were analysed on a Nu Plasma multi-collector inductively coupled plasma mass spectrometer, following the procedure described in Carolin et al. (2019). Individual 230Th ages with their 95% confidence intervals were calculated using an in-house Monte Carlo script that incorporates chemical blank errors, analytical uncertainties and initial 230Th/232Th uncertainties. The initial 230Th/232Th (atomic ratio) is estimated to be between 0.5 to 10.8 ppm (uniform distribution), equivalent to an activity ratio of 0.1 to 2.0. This range encompasses both the bulk earth value (230Th/232Th activity = 0.82) and the median detritus value calculated in a collection of speleothem studies (230Th/232Th activity = 1.5) (Hellstrom, 2006). Notably, SIB-4 samples exhibit large 230Th/232Th, with 90% of samples showing 230Th/232Th activity greater than 1000. This is due to high U content and low detrital Th content of the stalagmite. Thus, the age corrections related to detrital contamination are small (median of just 4 years), which is much less than the overall age error of ca. 100 years (2s).

Description: This dataset presents cave temperatures over the last glacial termination from stalagmite SC02 from Secret Cave in Mulu, Northern Borneo (4.063°N, 114.833°E). The temperatures are derived by the means of fluid inclusion microthermometry and published in Løland et al., (2022). The study shows that the cave temperature increased by 4.4 ± 0.3 °C (2 SEM) from the Last Glacial Maximum to the Holocene, amounting to 3.6 ± 0.3 °C (2 SEM) when correcting for sea-level induced cave altitude change. Included in the dataset are also the calculated dripwater delta-18O values.