The Rencontre Formation (locally pronounced Rown-Counter) is a

geological formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock expo ...

just below the

Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...

Ediacaran The Ediacaran ( ) is a geological period of the Neoproterozoic geologic era, Era that spans 96 million years from the end of the Cryogenian Period at 635 Million years ago, Mya to the beginning of the Cambrian Period at 538.8 Mya. It is the last ...

boundary in

Newfoundland Newfoundland and Labrador is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of . As of 2025 the population ...

, deposited in a fault-bounded enclosed basin. U-Pb dates obtained just below its base give a maximum age of . It is subdivided into five depositional phases, with two subsequent phases in a seven-phase series corresponding to the overlying

Chapel Island Formation The Chapel Island Formation is a sedimentary formation from the Burin Peninsula, Newfoundland, Canada. It is a succession of siliciclastic deposits, over thick, that were deposited during the latest Ediacaran and earliest Cambrian. Stratigraph ...

(900 m thick in this basin) and

Random Formation The Random Formation is a rock unit in Newfoundland dating to the early Cambrian period, dominated by tidal quartz arenites deposited in a near-shore environment, but also incorporating intertidal and open-shelf deposits, including glauconitic a ...

(250 m thick in this basin). #Phase one - 300 m - conglomerate dominated, some sandstone and minor siltstones #Phase 2 - 150 m - sands and silts #Phase 3 - 180 m - silts and minor sands; lower silts are grey-green,

glauconitic Glauconite is an iron potassium phyllosilicate (mica group) mineral of characteristic green color which is very friable and has very low weathering resistance. It crystallizes with a monoclinic geometry. Its name is derived from the Greek () m ...

, wave-rippled and mud-cracked; upper silts becoming red #Phase 4 - 200 m - coarse sands #Phase 5 - greater than 200 m -

arenite Arenite (from the Latin ''arena'', "sand") is a sedimentary clastic rock with sand grain size between 0.0625 mm (0.00245 in) and 2 mm (0.08 in) and containing less than 15% matrix. The related adjective is ''arenaceous''. The e ...

s and red silts.

References

{{Reflist Geologic formations of Newfoundland and Labrador Conglomerate formations of Canada Sandstone formations of Canada Siltstone formations of Canada