Eriksson's Dune Oldest Moon-Earth System Tidal Material

Eriksson's Dune is the oldest lithified tidal deposit on Earth and is located in the Barberton Mountains, South Africa. It is named after K.A. Eriksson, a South African geologist who first wrote about their discovery in 1978.

Eriksson's Dune is important not only for its geologic age but also because it is the oldest geologically recorded evidence of tidal rhythm.

The tide-modified sedimentation recorded in Eriksson's Dune material consists of interlaminated sandstones showing evidence of cycles. The rock dune consists of small sandstone conglomerates, cross-bedded sandstones, some laminated siltstone, and mudstone. There is no other geological analog like Eriksson’s Dune on Earth where the  Archean ocean's rhythmic tides can be studied from Earth's earliest history.

Scientists estimate that the distance between the Earth and the Moon 3.2 billion years (Ga) ago was about 70% of today's distance of 238,900-mile separation.  The Moon was only 167,000 miles from Earth back then. The Moon appeared fully 50% bigger in the skies of early Earth. 

The young Moon had a synodic month of about 26.2 lunar days. Earth’s Day was about a fast 13 hours. The consequence of such a close Earth-Moon System resulted in more powerful ocean tides than we experience today. 

As many as 15 different tidal layers have been seen in Eriksson’s Dune, reflecting varying strengths of the young Earth's tides. The layering preserved on this ancient shore offers an extremely unique window into the dynamics of the early Moon-Earth system.

Size of the Eriksson's Dune specimen: 83mm L X 62mm W X 20mm D, Weight: 150 grams; front and back enhanced by light oil to show the layering. The specimen has been lightly polished on both the front and back. The top, sides, and bottom are unpolished.

Ships with: Information, Certificate of Authenticity, and tag stand. Acrylic stand and photo cube not included. Eriksson's Dune PHOTO in situ and copy of relevant scientific articles included.

Add Eriksson's Dune, the world's most ancient beach specimen, to your diverse geological collection today. Learn and teach about geology on a whole new level by including the dynamics of the early Earth-Moon system with this terrific specimen!

Legally obtained in a trade with a scientific institution.