[U05-P08] Surface productivity and potential terrestrial ecology system in the central Okhotsk Sea during the middle-early Pleistocene
Keywords:Okhotsk Sea, Pleistocene, Surface productivity, Terrestrial biota
Here we present the first multi sterol biomarkers results from the central Okhotsk Sea using Site MD01-2414 (53o11.77’N, 149o34.80’E, water depth 1123 m) during the past 1.2-1.5 million years ago (Ma). We measured brassicalsterol, campesterol, and beta-sitosterol. Results show that the brassicalsterol, campesterol and beta-sitosterol varied from 0-1200, 0-12 and 10-40 ng g-1 dried sediment, respectively. The brassicalsterol shows both significant 23- and 41-kyr cycles, where the campesterol and beta-sitosterol show only precession cycle. This is the first report of sterols variations in the central Okhosk Sea during the 41-kyr world. Brassicalsterol variations may be mixed with surface productivity changes and terrestrial organic matter input, meanwhile the potential use of campesterol and beta-sitosterol as regional terrestrial plant biota changes may need further geographical verification in the future.