الصفحة 1
الصفحة 1
High-Latitude Bioerosion : The Kosterfjord Experiment
Bioerosion is the major force driving the degradation of marine skeletal carbonates and limestone coasts. A wide spectrum of mechanical and/or chemical boring, scraping or crushing organisms break down calcereous substrates, comprising various grazers, macroborers and especially microborers. Their traces on and within hard substrates are known from fossil carbonates as old as the Precambrian and serve as valuable palaeoenvironmental indicators. Bioerosion processes have been extensively studied in tropical seas, while corrsponding investigations from cold-temperate to polar settings remain sparse. For the first time, an experimental study yields insight into the pace of carbonate degradation and the chronology of boring community development along a bathymetric gradient in a high-latitude setting.
Marine Geochemistry
Since 1980 a considerable amount of scientific research dealing with geochemical processes in marine sediments has been carried out. This textbook summarizes the state of the art in this field of research. The topics comprise the examination of sedimentological and physical properties of the sedimentary solid phase, of pore water and pore water constituents, organic matter as the driving force of most microbiological processes, biotic and abiotic redox reactions, carbonates and stable isotopes as proxies for paleoclimate reconstruction, metal enrichments in ferromanganese nodules and crusts as well as in hot vents and cold seeps on the seafloor. A new chapter describes properties, occurrence and formation of gas hydrates in marine sediments. The textbook ends with a chapter on model conceptions and computer models to quantify processes of early diagenesis.
