【摘要】 对胶州湾沉积岩心J39、J37和J94进行了210Pb的测定,绘制了岩心中210Pb的垂直分布图,岩心J37和J94的210Pb呈两段分布模式,岩心J39的210Pb呈三段分布模式。胶州湾西北部大沽河口外海域近百年来沉积速率为0 768cm/a,沉积通量为0 7716g/(cm2·a)。胶州湾中部沉积速率为0 64cm/a,沉积通量为0 65g/(cm2·a)。胶州湾口外J94站沉积速率为0 54cm/a,沉积通量为0 81g/(cm2·a)。结果表明,胶州湾海域210Pb活度与悬浮体含量密切相关,悬浮体含量高的区域,210Pb活度高;反之,悬浮体含量低的区域,210Pb活度低。根据210Pb的垂直分布、活度和沉积速率及悬浮体含量,结合历史资料,对胶州湾近百年来的沉积环境和物质扩散进行了探讨。更多还原

【Abstract】 Based on the 210Pb method, sedimentation rates and sedimentation flux were measured in the Jiaozhou Bay of the Shandong Peninsula. The profile 210Pb showed that in the northwestern part of the Jiaozhou Bay 210Pb activity at coring station J39 appeared in a threesegment model (i.e. mixing segment, decay segment and background segment). It may be inferred that the mixing layer in the upper of the core was disturbed by the relatively active hydrodynamic condition and biological mixing. In this region, the suspended matter is higher than 20 mg/L. The sedimentation rate was calculated to be about 0768 cm/a and the sedimentation flux about 0771 6 g/(cm2·a). In the central region of the Jiaozhou Bay, 210Pb profile appeared in a twosegment model. The sedimentation rate and flux were respectively 064 cm/a and 065 g/(cm2·a). The suspended matter ranged from 5 to 15 mg/L. In the region off the Jiaozhou Bay mouth, 210Pb　profile also showed that 210Pb activity decaying with the depth appeared in a twosegment model. In this area, the suspended matter ranged from 3 to 5 mg/L.The calculated sedimentation rate and flux were respectively about 054 cm/a and 081 g/(cm2·a).The distribution trend of suspended matter in the Jiaozhou Bay was similar to that of 210Pb activity and dominated by the hydrodynamic action. 更多还原