Geological time description largely rests on an event based chronology based on the stratigraphical model. It uses a hierarchy of chronologically ordered geochronological units and boundaries. In order to be easily dealt with within large databases used by complex engineering systems, the geological time chronology must be formalized. Stratigraphical time successions should accordingly be descr...

New accelerator mass spectrometer radiocarbon ages from gastropods in shore deposits within the pluvial Lake Chewaucan basin, combined with stratigraphical and geomorphological evidence, identify an abrupt rise and fall of lake level at ca. 12 14C ka. The lake-level high is coeval with lake-level lows in the well-dated records of palaeolakes Bonneville and Lahontan, and with a period of relativ...

The high alpine valleys in the Southem Pyrenees are characterised by a many small lakes and ponds. They occur above 2000 m and are said to have been formed by glacial erosion. The sediments in these basins should, therefore, contain s t p tigraphic information since deglaciation, at least. An interesting and may be one of the most important of these basins is Lake Llauset in the Alta Ribagorca....