The Core

The bottommost 14 m or so of the core comprises impactites, made up of microcrystalline melt rocks, glasses, breccias and suevite. Above this the lake - fill sediments begin. Approximately 96 m of tubiditic sandstones uncomformably overlie the suevite, indicating initial fluvial input, followed by 280 m or so of dominantly fine - grained variably laminated mudstone, becoming coarser towards the top of the core. These differences in lithology reflect the development of the initial devastation into an actively accumulating lacustrine basin.

Macrofossils of fish and gastropod shells are good indicators of the freshwater setting, however layers of evaporite minerals such as gypsum attest to arid periods of climatic warmth in which the lake, at least partially, dried out. Most importantly, the sediments contain numerous and well - preserved organic microfossils including marine and freshwater algae and terrestrial sporomorphs . It is these microfossils, along with high resolution geochemical and isotope data, which form the crux of the investigation so far. This core provides us with an almost continuous record of climate in eastern Europe and western Asia in the earliest Cenozoic period. We and other scientists will be able to use it to discover how climate in continental areas relates to the oceanic signal seen elsewhere