Theories Of Snowball Earth

Theory of snowball Earth

The theory of snowball Earth expresses that the continents and oceans were covered in ice around 600 million years back. The Earth may have stayed in this frozen state, yet it was saved by the release of volcanic gasses. While the Earth was in this frozen state, chemical cycles were stopped and carbon dioxide gathered in the air causing an extreme greenhouse effect. Following 10 million years of freezing, the Earth defrosted in just a couple of hundred years. These events may have created the blast of life forms found in Cambrian fossils (Hoffman and Schrag 2000). Brian Harland proposed the possibility of a Precambrian great glaciation in 1964 after examining and studying broad glacial deposits. Later, in the late 1980's, Kirschvink authored the term Snowball Earth (Hoffman and Schrag 1999). From that point forward, a few people have added to the understanding of the possibility of Snowball Earth (Hoffman et al 1998, Hoffman and Schrag 2000).

The aim of this assignment is to compile research supporting and rejecting this theory. A presentation of the evidence will show what questions have been answered and what areas still

The fascinating question, however, is how would they know these events happened? Studies have been gathering proof about past climatic events. However, in this evidence, anomalies have been found to have happened during the late Proterozoic. Combining of evidence and relationships between these evidence, the theory of the snowball earth resulted.

Brian Harland, a geologist from the University of Cambridge, in 1960 presented the firs evidence of the snowball earth. He studied glacial deposits in Neoproterozoic sedimentary layers. (Kerr 2000) Very thick layer of carbonate rock existed above the Neoproterozoic glacial deposits. In cold water the carbonates tend to be soluble whilst they precipitate if exposed to warm water (Kerr