Biogenic components of the Baltic Sea sediments
Biogenic components of the Baltic Sea sediments
Russian Geology and Geophysics (December 2014) 55 (12): 1404-1417
- Atlantic Ocean
- Baltic region
- Baltic Sea
- Bazhenov Formation
- biogenic processes
- carbon
- carbonaceous composition
- clastic rocks
- clastic sediments
- Courland Spit
- Europe
- Gulf of Finland
- Jurassic
- major elements
- manganese
- marine sediments
- Mesozoic
- metals
- modern analogs
- mud
- nitrogen
- North Atlantic
- organic carbon
- organic compounds
- phosphorus
- sedimentary rocks
- sediments
- shale
- silica
- source rocks
The contents of biogenic components in 1511 samples of the Baltic Sea sediments (depth range 0-5 cm) are studied, and maps of their distribution are compiled. The sediments contain < or = 13.03% C (sub org) , < or = 1.33% N, < or = 9.0% SiO (sub 2am) , < or = 5.0% CaCO (sub 3) , and < or = 1.45% P. The maximum and elevated contents of components are found in the mud of the sea deeps. The more fraction < 0.01 mm the sediments contain, the higher are the contents of components. Four facies types of carbonaceous mud, precursors of shales, have been recognized: (1) shallow-water (lagoon) lime sapropel, (2) carbonaceous mud of the shallow-water Gulf of Finland, (3) carbonaceous mud of the middle-depth Baltic Sea, and (4) laminated carbonaceous metal-bearing mud. The latter type of mud is strongly enriched in manganese and ore-forming trace elements, which points to its formation in the stagnant environment. In composition the Baltic Sea mud is similar to petroliferous mudstones of the Bazhenov Formation in West Siberia and to ancient black shales.
