210pb sediment dating


In this direction, heavy metals were determined along the Three sediment cores were collected using divers at the sampling points shown in Figure 1.

The sampling point coordinates and main characteristics are presented in Table 1.

The lowest concentrations of heavy metals are found in the southern region of the Bay, near the inlet.In the northwestern and the western regions, the entry of sediments is substantial, and the area is highly influenced by human activities, such as sewage inputs, the channeling of rivers, deforestation and agricultural activities..The supply of river sediments is controlled by seasonal climatic cycles.Therefore, it is possible to conclude that the sedimentation rates in Guanabara Bay have been increased by 10 times the original rate.The factors that lead to these higher sedimentation rates can be sub-divided into (i) those that cause a potential large spatial scale increase in sedimentation rate, such as industrialization in the region and the growth of the population living around the bay and (ii) those that could produce a punctual increase such as construction of embankments, the expansion of the international airport and the rapid construction of transportation routes.The sediments of Guanabara Bay are considered highly enriched with Pb, Zn, Cu and Cr compared with the natural concentrations and other regions in the world.

You must have an account to comment. Please register or login here!