Geologic evolution of the Yukon River: implications for placer gold

Assessment of LiDAR and Spectral Techniques for High-Resolution Mapping of Sporadic Permafrost on the Yukon-Kuskokwim Delta, Alaska

“…The mouth of the Yukon River flowed south into the Gulf of Alaska during the late Pliocene, and swung northward to its current location from glacial damming during the Pleistocene [39]. This movement, along with the movement in the Kuskokwim River's channel, indicates long-term existence of deltaic sediments in the broader delta region.…”

Characterizing large river history with shallow geophysics: Middle Yukon River, Yukon Territory and Alaska

“…This drainage likely extended across the area presently occupied by the St. Elias and Coast mountains, and may have persisted through uplift of the southwestern Yukon ranges during the Pliocene (Tempelman-Kluit, 1980). The Yukon River would have been diverted to the northwest into central Alaska by the growth of late Cenozoic ice sheets by 2.6 Ma (Froese et al, 2000;Duk-Rodkin et al, 2001). This reorganization of Yukon River drainage may be recorded by late Pliocene gravel overlying MiocenePliocene lacustrine sediments in the Yukon Flats in central Alaska .…”

“…Through the late Tertiary, a south-flowing paleoYukon River is hypothesized, with a drainage divide near the Alaska border, connecting the area north of the Tintina Fault zone with the Pacific Ocean (Tempelman-Kluit, 1980;Duk-Rodkin et al, 2001;Froese et al, 2001). This drainage likely extended across the area presently occupied by the St. Elias and Coast mountains, and may have persisted through uplift of the southwestern Yukon ranges during the Pliocene (Tempelman-Kluit, 1980).…”

Geogene and anthropogenic controls on the mineralogy and geochemistry of modern alluvial–(fluvial) gold placer deposits in man-made landscapes in France, Switzerland and Germany

“…The shape and surface characteristics of platinum-group elements, gold, and quartz grains examined with the scanning electron microscope show transit-and transport-related changes (Nikolayeva and Yablokova, 1989;Southam and Beveridge, 1994) and the outward appearance of particles of precious metals may provide valuable evidence for exploration geologists so as to guide them to the primary deposit of placer-type minerals (De Oliveira and De Oliveira, 2000;Duk-Rodkin et al, 2001;Nakagawa et al, 2005). In the current study, the mineral grains of precious metal alloys have been quantified and classified as to their roundness using the classification schemes by Pettijohn et al (1973) and Tucker (2001).…”