广州地区第四纪沉积的年代学研究

CHRONOLOGY OF QUATERNARY SEDIMENTS IN GUANGZHOU AREA

本文根据75个^(14)C 和22个热释光年代资料,央合沉积学、硅藻和微量元素分析,作者认为广州地区第四纪沉积年代可划分为七个阶段:Q_2(距今70—20万年前)的冲积阶段;Q_3~1(距今20—5万年)的风化剥蚀阶段;Q_3^(2-1)(距今(5—3万年)的冲洪积阶段;Q_3^(2-2)(距今3—1.8万年)的海进阶段;Q_3~3(距今1.8—1.2万年)的风化与冲洪积阶段;Q_~1～Q_4~2(距今1.2—0.25万年)的海进阶段;Q^3_4(距今2500年)的海平面基本稳定与陆地前伸等阶段.

According to 75 ^(14)C dating and 22 thermoluminescence data,in com- bination with the analysis of sedimentology,diatom and trace elements the authors consider that the age of Quaternary sediments in Guangzhou area can be divided into seven phases.(1) the alluvial phase in Q_2(ab- out 700—200 thousand yr.B.P.,(2) the weathering action and denud- ation in Q_3~1 (about 200—50 thousand yr.B.P.,(3) the alluvial and diluvial phase in Q_3^(2-1) (about 50—30 thousand yr.B.P.,(4) the marine transgression phase in Q_3^(2-2) (about 30—18 thousand yr.B.P.,(5) the weathering action and alluvial-diluvial phase in Q_3~3 (abaut 18—12 thous- and yr.B.P.,(6) the marine transgression phase in Q_4~1—Q_4~2 (about 12— 2,.5 thousand yr B.P.,(7) the steady sea level on the whole and land expansion phase in Q_4~3 (after 2500 yr.B.P.).