| 摘要: | 摘要： We describe the orbital-scale environmental variation around Papua New Guinea (PNG) for the last 400 ka based on the environmental magnetism. Six magnetic parameters and the δ18O record of the core MD05-2928 are presented in the study. Results of magnetic analyses reveal opposite responses to different environmental conditions: Magnetic minerals were relatively fewer and finer in interglacial periods and were more and coarser in glacial periods. The reason could be suggested: In interglacial periods, sediments coming from central New Guinea were transported by the coastal currents in the northern Coral Sea and then imported to the core site location. Magnetic minerals would be relatively fewer and finer due to this longer transportation process. In glacial periods, the routes of the currents might regress seaward with reduced current intensity because of lower sea level. Main sediment sources would shift to the Papuan Peninsula relatively near the core site, and therefore, the magnetic minerals became more and coarser. Further, period analyses using the eccentricity, tilt, and precession (ETP) curves and the wavelet spectra were applied to the study to analyze the periodicities embedded in the parameters. Results of both period analyses clearly present the Milankovitch periods, indicating the dominance of the orbital forcing in this area. The strongest signal of 100-ka period reveals that sea level change played the dominant role in long-term environmental setting for the past ~400 ka. However, influences of 40- and 20-ka periods, possibly related to regional precipitation, should also be considered though they might be second factors affecting the environmental variation around PNG.
其他題名： Earth Planet Sp
出版者： Berlin/Heidelberg: Springer Heidelberg
出版日期： 2015-08-14
出處： Earth, Planets and Space, 2015-08, Vol.67 (1), p.128--16, Article 128
資源來源： Publicly Available Content Database
版權： 2015 Huang et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. restricted use info:eu-repo/semantics/openAccess
版權： Huang et al. 2015
版權： The Author(s) 2015
識別號： ISSN: 1880-5981
識別號： ISSN: 1343-8832
識別號： EISSN: 1880-5981
識別號： DOI: 10.1186/s40623-015-0300-5 |
