Amino acid chronology in the fossil planktonic foraminifera, Pulleniatina obliquiloculata from Pacific Ocean

• Published in: Geophysical research letters Vol. 22; no. 17; pp. 2353 - 2356
• Main Authors: Harada, Naomi, Handa, Nobuhiko
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01.09.1995; American Geophysical Union
• Subjects: Age; Age determination; Amino acids; Chronology; Earth sciences; Earth, ocean, space; Exact sciences and technology; Foraminifera; Fossils; Invertebrate paleontology; Marine; Pacific Ocean; Paleontology; Pulleniatina obliquiloculata; Racemization; Reaction kinetics; West Pacific; Equatorial Pacific; Pacific Ocean; ISEW, Western Equatorial Pacific; IS, Equatorial Pacific; geochronology; stable isotopes; models; O-18; epimerization; amino acids; planktonic taxa; accuracy; C-14; foraminifera; absolute age; Protista; kinetics; racemization; correlation coefficient; marine sediments
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/95GL02112

This study was undertaken to evaluate the accuracy of amino acid chronology using a first‐order kinetic model and was carried out using a fossil planktonic foraminifera, Pulleniatina obliquiloculata (P. obliquiloculata), in the sediment from the western equatorial Pacific Ocean. The extent of racemization reaction of aspartic acid and glutamic acid and the extent of epimerization reaction of isoleucine were measured and compared with reference ages obtained from 14C dating and the distribution patterns of δ18O. The relationships between the extent of racemization/epimerization reaction of these amino acids and reference ages were linear along with a high correlation coefficient (r = 0.99–0.95), suggesting that amino acid chronology utilizing a first‐order kinetic model could be appropriate for determining geological ages ranging from the present to 106 yBP within the average errors of 4.5, 12.3, and 15.8% for Asp, GIu, and Ile, respectively.