摘要
本文通过对黄海QC_2钻孔沉积岩心古地磁样品测量,对黄海全新世松散沉积物进行了磁性地层的划分.主要认识是:1.黄海海域沉积岩心记录了两次地磁极漂移,定名为黄海Ⅰ、黄海Ⅱ,其年龄分别约2600—3100年和6000—6400年.2.黄海Ⅰ和黄海Ⅱ对全新世可作进一步划分,分别是晚一中全新世和中一早全新世的分界.3.从黄海Ⅰ和黄海Ⅱ是气候地层的分界线这一现象表明,黄海地域地磁场的变化与古气候存在着内在联系的相关性.
There have been very few reports about Holocene geomagnetic pole drifts (short-term polarity events), and als?their geological significance has gained Httle concern. This paper, howeyer, discusses these questions by studying the geomagnetism of Core QC2 in the Yellow Sea, which are testified by C14 dat-ing and palynological evidences.
In the Research Project of Correlation of Stratotype and Strata in the China Seas and Adjacent Lands', a core in good quality, Core QC2, was geo- magnetically analyzed by continuously sampling in great density, the intervals of 3.75-4.2m, 8.2-8.7m and 16.8-17,lm deep are three polarity reverse sections. According to the C14 date of 9910 100 a. B. P. at 15.02ra, the rever-sal at 16.8-17.lm ought to be the Gethornburg Event, and the reversals at the depths of 3.75-4.2m and 8.2-8.7m, temporarily named Yellow Sea I and Yellow Sea II, should be at ages of 2600-3100 and 6000-6400 a. B. P. respec-tively, inferred by the sedimentary rate. This part of the core can be palyno-logically divided into four zones, namely Zone I (17.1-14.3m), Zone II (14.3-8.Om), Zone III (8.0-3.3m) and Zone F (3.3-0.0m). The Yellow Sea II and Yellow Sea II are approximately cresponding with the boundary of Zone II and Zone II and that of Zone III and Zone IV respectively, reflecting a close relation between geomagnetism and climate, and also providing evidences for further dividing the Holocene with Gethornburg Event as the bottom into paleao-, ealier-, mid- and later-Holocene.
The short-term geomagnetic polarity drifts present dates to the Holocene strata, also provide information for the division of Holocene,
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
1989年第2期35-40,共6页
Marine Geology & Quaternary Geology
