The use of the 210Pb method for preliminary evaluating the sedimentation rate in Amazon river mouth
Journal Title: Annals of Warsaw University of Life Sciences – SGGW. Land Reclamation - Year 2010, Vol 42, Issue 1
Abstract
This investigation reports the preliminary results for determining the sedimentation rate at the Amazonas River mouth, Brazil, by the 210Pb method. The CIC (constant initial conentration) of unsupported/excess 210Pb model was successfully applied to one sediments core. The measurements were made in a sediments core comprising ten samples 10 cm – thick each. The year of the sampling (2006) was used as reference for the establishment of the rate of sedimentation from the beginning of the top of the testimony. However, the atmospheric conditions and climate in Amapá State, Brazil, claimed for optimization of the results. Because the Channel North is opened into the Atlantic Ocean, it exhibits a huge water volume, causing a permanent motion of sediments and water. So, heavy waves are formed at the water surface, stirring the upper sand strata. Only at a depth of 40–50 cm the profile tends to be more homogeneous, where it is mostly com- posed by ne sand and very fine sand. Thus, it is reasonable utilize the CIC model from 210Pb data, which allows estimate a sedimentation rate corresponding to 0.61 g/cm²yr and a mean linear rate of 0.8 cm/yr. The 238U and 210Pb activities in the sedi- ments allowed the reconstruction of the sedimentation processes over a period of about 130 years.
Authors and Affiliations
SOPHIE ALTHAMMER, ERICH FOßHAG, HARALD HOFFMANN, JOSÉ CARDOSO NERY, DANIEL BONOTTO
Keywords
Related Articles
- EP ID EP118827
- DOI -
- Views 113
- Downloads 0
Analiza związku warunków hydromorfologicznych ze zróżnicowaniem biocenotycznym na przykładzie rzeki Zwoleńki
W artykule została przedstawiona ocena stanu ekologicznego dwóch zróżnicowanych pod względem hydromorfologicznym odcinków rzeki Zwoleńki. Odcinki badawcze o długości 500 m zlokalizowano w korycie naturalnym (Siekierka) i...
On the erosion due to inclined jets
Some preliminary experiments and studies regarding scour processes on a mobile bed caused by inclined jets issuing from a sluice gate are presented. Tests with submerged tailwater conditions have been carried out using d...
Flood threat to the territories below the water dam in conditions of occurrence of extreme hydrological phenomena
The course of the flood in July 2001 and passage of the freshet wave through the water reservoir Chańcza on the Czarna Staszowska River was analyzed. Culmination of this wave equaling 418.62 m3•s–1 was two times higher t...
Slope erosion control with the use of fly-ash and sewage sludge
The paper presents alternative methods of the earth slopes reinforcement. The techniques proposed utilise recycled materials such as fly-ash and sewage sludge. It is described how implementation of fly-ash made capping mat...
Vertical and horizontal permeability measurements in organic soils
The paper is referring to vertical and horizontal laboratory permeability measurements in soft organic soils. The estimation of anisotropic permeability in soft organic soils, as peats, requires to use a special apparatu...