Research Coccolithophores Clastic systems Ocean and climate Fieldwork Lab equipment		Coccolithophores Coccolithophores are a group of marine, unicellular algae. Their morphology is characterised by an exoskeleton composed of numerous minute calcite platelets - the coccoliths - that are readily preserved in the sedimentary record. Coccolithophores are one of the main groups of marine phytoplankton playing key roles in the marine ecosystem as primary producers and in marine biogeochemistry, and preserve the composition of the overlying water mass conditions. Since coccoliths are phenomenally abundant in sea-floor sediments, they are valuable indicators of the paleo-environment and of climate-induced paleoproductivity changes. Clastic systems Siliciclastic systems are, in contrast to carbonate systems, characterized by high input of material from the hinterland. They are, therefore, directly coupled with the climatic conditions on land which control type and intensity of weathering and the amount of material available for the transport towards the ocean. Furthermore, climate determines the rates of fluvial runoff. Material supplied to the ocean forms sediment bodies - along the coasts, on the continental shelf, at the continental slope, and last but not least in the deep ocean basin. These deposits contain, as land-derived, also a certain amount of organic material which delivered from land is responsible for its economical importance (hydrocarbons). Ocean and climate Changes in the carbonate system of the ocean have a significant impact on global climate changes. As an example, the carbonate production in surficial waters causes intense CO2 exchange with the atmosphere, and the high buffering capacity of the deep and intermediate water masses can act as an efficient storage of additional atmospheric CO2. However, the latter process should not be regarded as a license for continuation of increased anthropogenic CO2 emissions. The highly interconnected physical, chemical and ecological processes that control the carbonate production in surface waters are the subject of decades of research and are still poorly understood. Fieldwork Within the framework of more than 20 years of cooperation with the Geological Survey of Austria in Vienna our working group carries out geological mapping in the Northern Calcareous Alps. Work was concentrated on compilation of the map sheet ÖK 114 Holzgau in the scale 1: 50.000. Basic mapping and field work included 24 maps compiled by diploma students, which were supported by funds from the Geological Survey of Austria. In addition, R. Henrich has carried out continuously over the past 15 years own field studies and mapping campaigns in complex or difficult accessible parts of the mountains. Beside this main enterprise in the last years we have started with geological mapping in a new area, i.e. on sheet ÖK70 "Waidhofen an der Ybbs" located in the eastern part Northern Calcareous Alps, which is constructed of comparably shallow elevated frontal mountain chains. Lab equipment Our laboratory equipment enables numerous possibilities for sedimentological tests. The capabilities are specialised for clastic and carbonatic, unconsolidated sediments. A freeze drier and a elutriating lab are used for sample preparation, the separation of distinct fractions of fine sediments can be done in the Atterberg-lab, which has a capacity of about 120 tubes. For the separation of coarse, dry samples a Sonic Sifter is allocated. To analyse grain size spectra two Sedigraphs are employed. Measurements of carbon and sulphur contents are done with a CS combustion analyser. For microscopy we use classical light microscopes and a scanning electron microscope. These facilities can also be used by other scientists.

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University of Bremen	Research Group Sedimentology – Palaeoceanography Faculty of Geosciences | FB5

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