Late Jurassic–Early Cretaceous Sandstones of the Algan Formation: Composition, Origin, and Provenance Areas (Northwest of the Koryak Highland)

Abstract—This article presents the results of the petrographic and mineralogical study of the sandstones of the Algan Formation. Sandstones are represented by ultrafine-, fine-, and medium-grained quartz–feldspar greywackes according to the classification of (Shutov et al., 1972). Two tectonically juxtaposed sandstone lithotypes were distinguished. These lithotypes were deposited in two basins of different ages from high- and medium-velocity turbidity currents off the coast in moderately deep marine environments. Sedimentation conditions are typical of areas near river deltas and prodeltas. The provenance areas of these basins were different, being associated with volcanic areas of different-ages in the north of the studied region.