We present data on bulk density, inorganic geochemistry (Ti, Ca, Al, Mn, and Fe), pollen (Quercus, Moraceae, Pinus, tropicality index), and sediment geochemistry (TOC, TN, TOC/TN) from Lake Petén Itzá. In 2006, Lake Petén Itzá was drilled by the International Continental Scientific Drilling Program (ICDP), obtaining seven lacustrine sediment records: PI-01, PI-02, PI-03, PI-04, PI-06, PI-07, and PI-09. Here, we present data from Site PI-1 (16.99951°N, -89.79566°W), located in the northern part of the lake. At the Continental Scientific Drilling Facility at the University of Minnesota, bulk density was analyzed using a GEOTEK multi-sensor core logger with gamma-ray attenuation, with measurements taken every 0.5 cm. Inorganic geochemistry data were obtained using X-ray fluorescence (XRF) with a Cox Analytical Itrax Core Scanner. Cores from PI-1 were measured with a Cr-tube at 30 kV, 55 mA, 15-second exposure, at 1-cm resolution. XRF data are presented in counts per second (cps). Subsequently, data were transformed to centered log-ratio (CLR). CLR values were obtained by dividing each element's concentration by the geometric mean of the elements measured at the same depth, then taking the natural logarithm of the ratio. CLR results have no units. Pollen data include new data from Site PI-1 (189 samples) presented by Martínez-Abarca et al. (2024). For each sample, pollen abundances were converted into percentages of the pollen sum. A "tropicality index" was calculated as ln(Moraceae% + 1) / ln(Quercus% + Pinus% + 1). Bulk organic geochemistry includes measurements of total carbon (TC) and total nitrogen (TN) using a Carlo Erba NA1500 CNS analyzer. Total inorganic carbon (TIC) was measured coulometrically using a UIC (Coulometrics) 5014 CO2 coulometer coupled with an AutoMate Carbonate Preparation Device, with approximately 15 mg of sample used for analysis. Total organic carbon (TOC) was calculated by subtracting TIC from TC. TOC/TN ratios were calculated on a molar basis. Depth data correspond to the "Core composite depth below lake floor (CCLF)" or "Master composite depth (MCD)", which accounts for core recovery gaps and depth inconsistencies, while age data are based on the age-depth models presented by Martínez-Abarca et al. (2024).

Empty values were not measured/counted at the specific depth