The case for snowball earths is based on different lines of evidence.

1. The global distribution of Sturtian and Marinoan glacial deposits, and the broad synchroneity of the latter based on seawater carbon isotope anomalies consistently framing the glacial strata.
2. The association of glacial or glacial marine deposits with thick carbonate (limestone or dolostone) successions, which occur preferentially in the warmest parts of the surface ocean.
3. Deposition of glacial or glacial marine strata close to the paleo-equator during the Marinoan, Sturtian and Makganyene glaciations, indicated by a growing body of reliable paleomagnetic data from different regions.
4. Paleomagnetic data suggesting multiple reversals of the geomagnetic field, implying hundreds of thousands to millions of years, during the Marinoan glaciation near the paleo-equator.
5. Paleomagnetic data showing that thick Proterozoic carbonate successions formed at low-latitudes, indicating that the meridional climate gradient was not reversed (warm poles and cold equator) as would be true if the rotation axis had been highly oblique (to the ecliptic) as earlier proposed to explain low-latitude glaciation.
6. Sedimentary iron (± manganese) oxide deposits (banded iron formation) found exclusively in glacial marine strata after 1.9 Ga, indicating widespread anoxia (consistent with an ice-covered ocean) and an increase in the ratio of Fe to S entering the ocean (consistent with ice-covered continents).
7. Deep flooding of previously shallow-water shelves and platforms after the Sturtian and Marinoan meltdowns, sustained after isostatic readjustments, reflecting slow tectonic subsidence over millions of years under the ice.
8. The deposition of post-glacial "cap carbonates" with unusual sedimentary structures on continental margins and inland seas globally in the aftermaths of the Sturtian and Marinoan glaciations. Regional-scale glaciations lack cap carbonates or they are poorly developed. Their origin remains controversial but they are predicted to occur in the greenhouse aftermath of a snowball earth.
9. Part-per-billion concentrations of the platinum group element iridium found at the base of Sturtian and Marinoan cap carbonates are interpreted as an extraterrestrial dust component trapped in ice for millions of years and released upon deglaciation. This new result (Bodiselitsch et al., 2005) awaits confirmation and testing, but the suggested time scale (~12 million years assuming an extraterrestrial flux equal to that of the last 65 million years) for glacial entrapment is suggestive of a snowball earth.
10. Boron isotope data for carbonates deposited before and after the Marinoan glaciation, which suggest a large decrease in seawater pH, consistent with a buildup of CO₂ acid. A decrease in continental weathering relative to mid-ocean ridge hydrothermal exchange should shift the boron isotope composition of seawater in the direction opposite to that observed, so this is not a viable alternative explanation. This is another new result (Kasemann et al., 2005) that requires confirmation and further analysis.