The Composition, Source, and Depositional Environment of Lower Cretaceous Sediments in Northern Sikhote-Alin

The structure, composition, and source areas of Lower Cretaceous terrigenous sediments and geodynamic conditions for their deposition in the Northern Sikhote-Alin are considered. The study established that in terms of mineralogical and geochemical parameters the sandstones, being either petrogenic or first cycle deposits formed by the products of the breakdown of bedrock from the source areas, correspond to graywackes. They are characterized by low maturity, weak lithodynamic reworking of parental rocks, and high rates of deposition. The paleogeodynamic interpretation of the data suggests sedimentation in the Early Cretaceous along the continent–ocean boundary in the basin related to large-scale strike-slip motions along the transform faults. The source area combined sialic land formed by granite-metamorphic and sedimentary rocks, a mature and deeply eroded continental-margin arc, and fragments of Jurassic–Early Cretaceous accretion prisms of the Sikhote-Alin with ophiolites incorporated into their structure. All this allows the studied deposits to be considered as a part of the Early Cretaceous Zhuravlevka pull-apart terrane.