The geochemical characteristics of the bottom sediment in the pockmark area of the eastern part of the Gulf of Finland

Abstract

It is the first time pockmark-like structures have been detected in the south-eastern part of the Gulf of Finland with the help of a side-scan sonar and a profile recorder. The analysis of the distribution of microcomponents in the bottom sediment indicates that the pockmark area is located in the geochemical barrier border zone where the reducing medium of the incoming mineralized solution meets the highly oxidizing sea water medium. The hydrodynamic and geochemical processes in the pockmark zone create focal areas of anomalous microenvironment and affect the composition and development of benthos.

Keywords

• pockmark
• Baltic Sea
• geochemical barrier
• rare earth elements