Description: In this study, we demonstrate the utility of amino acid geochronology based on single-foraminiferal tests in Quaternary sediment cores from the Queensland margin, Australia. The large planktonic foraminifer Pulleniatina obliquiloculata is ubiquitous in shelf, slope, and basin sediments of north Queensland as well as pantropical oceans. Fossil tests are resistant to dissolution, and retain substantial concentrations of amino acids (2-4 nmol/mg of shell) over hundreds of thousands of years. Amino acid D and L isomers of aspartic acid (Asp) and glutamic acid (Glu) were separated using reverse phase chromatography, which is sensitive enough to analyze individual foraminifera tests. In all, 462 Pulleniatina tests from 80 horizons in 11 cores exhibit a systematic increase in D/L ratios down core. D/L ratios were determined in 32 samples whose ages are known from AMS 14C analyses. In all cases, the Asp and Glu D/L ratios are concordant with 14C age. D/L ratios of equal-age samples are slightly lower for cores taken from deeper water sites, reflecting the sensitivity of the rate of racemization to bottom water temperature. Beyond the range of 14C dating, previously identified marine oxygen-isotope stage boundaries provide approximate ages of the sediments up to about 500,000 years. For this longer time frame, D/L ratios also vary systematically with isotope-correlated ages. The rate of racemization for Glu and Asp was modeled using power functions. These equations can be used to estimate ages of samples from the Queensland margin extending back at least 500,000 years. This analytical approach provides new opportunities for geochronological control necessary to understand fundamental sedimentary processes affecting a wide range of marine environments.

Description: Sediment grain size data for vibrocore PVL10-50, southern California shelf

Description: Vibrocore radiochemical data collected from the RV Melville, cruise MV1211.

Description: Sediment grain size data for box core OC-50, southern California shelf

Description: Sediment grain size data for vibrocore OC-50, southern California shelf

Description: Radiocarbon and calibrated ages and D/L of Aspartic and Glutamic acids of the nine specimens of N. taphria and seven specimens of P. tenuisculpta and used to calibrate the rate of amino acid racemization, plus information on live-collected specimens. Both species were collected at PVL10-50 and OC-50 sites (southern California shelf).

Description: Boxcore radiochemical data collected from the RV Melville, cruise MV1211.

Description: Table S1. Summary of radiocarbon-calibrated shell ages of Nuculana taphria and Parvilucina tenuisculpta estimated by amino-acid racemization (with 95% confidence intervals), with water depth (m), sampling year, and D/L of Aspartic and Glutamic acids. Both species were collected at PVL10-50 and OC-50 sites (southern California shelf).

Description: Estimates of shell loss of Parvilucina tenuisculpta and Nuculana taphria from the uppermost seabed increments based on one-phase exponential model (λ) and random-time two-phase exponential model (λ1, λ2, and sequestration τ) in the entire Southern California Bight and at two stations (PVL10-50 and OC-50). AICc refers to the Akaike Information Criterion corrected for small sample size.

Description: Sediment grain size data for box core PVL10-50, southern California shelf