Small fossils provide key clues for interpreting environmental changes

[OKIsItJustMe]

http://www.basqueresearch.com/berria_irakurri.asp?Berri_Kod=2316&hizk=I

2009/7/23

Small fossils provide key clues for interpreting environmental changes

The Micropalaeontology team at the Department of Stratigraphy and Palaeontology at the University of the Basque Country (UPV/EHU) is working on the study of microfossils under the direction of Mr Julio Rodríguez Lázaro. The concentrations of these types of fossils and the composition of their shells can provide much information about the conditions of life thousands or even millions of years ago. These microfossils once belonged to aquatic organisms and their analysis enables a knowledge of past ocean and lake characteristics to be gained – data that is highly significant in the study of climate change.

Microfossils are found in rocks and are very abundant. Samples are gathered, the species are identified and the geochemical analysis of their shells is undertaken, which enable the characteristics of the water in which these organisms lived to be identified. The UPV/EHU team has been collaborating for many years with a research team from Bordeaux (France) and mainly works with foraminiferes and ostracods. These organisms have inhabited the planet for many millions of years, in such a way that the variations observed within their populations help to describe environmental situations in the past.

The present is the key to the past

But, to understand what happened to these organisms in the past, it is necessary to know how they live today. To this end, current samples are gathered and where and in what conditions they live are analysed. Very different zones are studied in order to know how these organisms live in very distinct situations. The UPV/EHU team worked in areas such as the Cantabrian coast, the coast of Morocco, the Atlantic coast of the United States and in oceanic waters at various places in South America, as well as with the continental waters of the river Ebro (Spain)

The data obtained in the studies were compared with samples of different layers of the ocean beds or lakes, in order to observe the changes in the distribution of the microfossils. Thus, for example, a species that can be currently observed living in cold Nordic waters appeared in great quantities in the south of the Gulf of Bizkaia during a determined period, indicating that, in that period, the waters of the Cantabrian Sea were much colder than they are now. Dating of these samples confirm that this period coincided with the last Great Ice Age and detected by the UPV/EHU team in waters of the Basque continental shelf and carbon dated (14C) at about 23,000 years.

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[TheCowsCameHome]

1. And here I though this was a McCain thread.......

Oh well.