Abstract <p>It is generally accepted that the northwest domain of the Yenisei Ridge is composed of the Late Neoproterozoic fragments of the oceanic lithosphere and oceanic island arcs. Not long ago, we found evidence of an ancient continental basement in the western half of this domain, which was proposed to be named the Kiselikha Terrane. The idea was based on indirect data and required more convincing evidence. The paper presents data on arkosic sandstones and gritstones of the recently identified Melnichny Fm., made of disintegrated material of the Early Precambrian gneisses and granitoids of the Siberian basement. A significant portion of this material was obtained from local sources in the immediate vicinity of the sediment burial area. The stratotype of the formation is described, and its mapping features are specified. We suggest that Melnichny Fm. was formed simultaneously with the Korda Fm. of the eastern part of the Ridge. The arkoses of Korda Fm. began to accumulate approximately 1250 million years ago due to rifting, which uncover the Early Precambrian basement on the incipient passive margin of the Siberian paleocontinent. The Melnichny Fm. is represented by deeper-water facies, located closer to the frontal part of this margin. Provided data confirms the continental nature of the Kiselikha Terrane and its Siberian origin.</p>