Dissolved H2 concentrations up to the mM range and H2 levels up to 9-58% by volume in the free gas phase are reported for groundwaters at sites in the Precambrian shields of Canada and Finland. Along ...

The early earth / editor, D.R. Nelson. Earth's formation and first billion years / D.R. Nelson. The early Precambrian stratigraphic record of large extraterrestrial impacts / B.M. Simonson, G.R.

The Precambrian eon is vast, almost unimaginably so. In fact, before some fossil discoveries were made late in the 20th century, it was considered unknowable -- evolution's dark ages. The Precambrian ...

The Great Unconformity is a major gap in Earth's geologic record. The missing layer between Precambrian and Cambrian rocks represents a gap of around a billion years of history. Among much debate ...

At the University of California, Professor Charles Bernard Lipman, plant physiologist, took a chunk of pre-Cambrian rock. The piece came from Canada. Geologists considered it 100 to 200 million years ...