Testing of the Snowball Earth hypothesis in terms of the cap carbonates, Namibia

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The purpose of this study is to test the Snowball Earth hypothesis, which suggests that the entire Earth surface was covered with icesheet in several times during Neoproterozoic era. For this purpose, we visited Namibia in winter seasons from 2001 to 2003 and investigated ouccrops of diamictites, cap carbonates, and iron formations associated with diamictites. The rock specimens sampled from Ghaab diamictites near Fransfountain was used for rheological analysis which revealed that the diamicites was compressed by the overburden pressures after deposition. The cap carbonates were used for geochemical analysis. The calcite dolomite cycles found in Rasthof cap carbonates were correlated in several outcrops. A slump strucutes occurring in the cycles suggested that the calcite dolomite cycles existed before the strata was consolidated. This means that the dolomites of cap carbonates were primary origin. The carbonate rocks were also used for geochronological studies. The Ediacaran fossils found in southern Namibia and the White Sea area, Russia were also studied. The results of these studies were discussed in terms of several working hypotheses of the Neoproterozoic glaciation. The testing of the Snowball Earth hypothesis and its relation to the emergence of animal life of the Ediacaran type are still important topics in Earth Science.