The Mississippi River discharge effectively shaped the dynamics of the Loop Current in the Gulf of Mexico during transient climates and interglacials, and reacted in response to changes in sea level and atmospheric circulation. We here provide proxydata records from piston core M78/1-181-3 PC. The ~12 m-long core was recovered from the Mississippi Alabama shelf very close to and southeast of the recent Mississippi delta (29°00.00'N 88°20.00'W) from 804 m water depth during R/V Meteor Cruise M78/1 in 2009 (doi:10.2312/cr_m78_1). The proxyrecords cover the last ~42 kyrs at centennial resolution. This dataset contains sand (>63 µm), bulk CaCO3, calculated coarse carbonate and biogenic silica percentages. Sampling and analytical studies were carried out from 3 cm to ~1220 cm core depth at ~5 cm spatial resolution. Total inorganic carbon (TIC), which is a reflection of CaCO3 (CaCO3 = TIC ⁎ 8.333), was calculated as the difference between total carbon (TC) – measured on bulk sediment material – and total organic carbon (TOC) – measured on de-calcified sediment samples via Carlo-Erba NA-1500 Elemental Analyzer at GEOMAR. Percentages of coarse carbonate were calculated to assess varying abundances in foraminifers. Biogenic silica (opal) was measured via an automatic extraction analysis at GEOMAR.