The name Dragon Formation was proposed by Bérard (1965) for a succession of detrital sedimentary rocks mapped over a distance of 15 km between the Bérard and Four Bears lakes in the northern part of the Labrador Trough (sheet 24L08). The unit is structurally located between the Sokoman Formation (called the Fenimore Formation by Bérard, 1965) and the overlying Chioak Formation. The name comes from Dragon Lake (58°17′N, 70°13′W, sheet 24L08), located in the northern part of the Labrador Trough, a few kilometres south of Bérard Lake. The unit lies within the autochthonous/parautochthonous Bérard Lithotectonic Zone (Clark and Wares, 2004).

The Dragon Formation was described as a succession of rhythmites by Bérard (1965). West of Siugak Lake (formerly Chioak Lake) (sheet 24L08), the unit is ~35 m thick. According to Bérard (1965), the presence of decimetric arkosic sandstone beds near the top of the Dragon Formation marks a stratigraphic transition with the overlying Chioak Formation. However, the Chioak Formation was interpreted as an erosional unconformity with all other sedimentary formations in the northern Trough by Clark and Wares (2004). The Dragon Formation consists of thin beds of greenish grey siltstone alternating with thin beds of black shale. Bérard (1965) mentions that sedimentary rocks contain graphite, stilpnomelane, anthraxolite (pyrobitumen), pyrite and chamosite (Fe-chlorite).

Following the reworking of the Labrador Trough stratigraphic column by Clark and Wares (2004), the name Dragon Formation was abandoned and the rocks of this unit were incorporated into the Menihek Formation (informal unit pPme1).

In the Mélèzes River area (latitude 57°35′N, sheet 24F12), slate and siltstone beds are present at the apparent base of a unit referred to as the Larch River Formation by Bergeron (1954) (see Bérard, 1965; Clark, 1979). The Larch River Formation is now interpreted as equivalent to the Menihek Formation. In addition, Clark et al. (2008) reported the presence of metalliferous black shale beds between iron-bearing rocks of the Sokoman Formation and sandstone, siltstone and mudstone beds typical of the Menihek Formation in the Schefferville area. Black shale occurs in beds ranging from 2 to ~30 m thick and is regionally distributed over different lithotectonic zones. Thus, the stratigraphic position of the Dragon Formation is homotaxial to that of argillaceous sedimentary rocks at the base of the Menihek Formation elsewhere in the Trough. Clark and Wares (2004) consider the Dragon Formation to be a sandy-argillaceous member of the Menihek Formation (pPme1). Therefore, these authors recommended that the name Dragon Formation be abandoned.

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