Smithsonian miscellaneous collections . > E IS 1 I fe NO. II lYATAYET SITE, ALASKA—HOPKINS AND GIDDINGS 9 gray silt, therefore, is believed to be derived by vv^eathering from theunderlying congeliturbate. The ashy-gray silt resembles the characteristic A2 horizon of anancient podzol. The underlying 2 or 3 inches of stained congeliturbaterepresent the B horizon. Kellogg and Nygard (1951, pp. 49-58) re-port similar but much thicker and better-developed podzol profiles ata few localities elsewhere in Alaska. A thick turf layer forms the Aihorizon of modern podzols but has not been preserved in
Smithsonian miscellaneous collections . > E IS 1 I fe NO. II lYATAYET SITE, ALASKA—HOPKINS AND GIDDINGS 9 gray silt, therefore, is believed to be derived by vv^eathering from theunderlying congeliturbate. The ashy-gray silt resembles the characteristic A2 horizon of anancient podzol. The underlying 2 or 3 inches of stained congeliturbaterepresent the B horizon. Kellogg and Nygard (1951, pp. 49-58) re-port similar but much thicker and better-developed podzol profiles ata few localities elsewhere in Alaska. A thick turf layer forms the Aihorizon of modern podzols but has not been preserved in the buried Suborttle Brownf«r»»t Sou J Buriod podzol Saborctlc BrownForett Soil. EXPLANATIONof . f , I SOIL COLORS I I Sonfly silt. Ashy-crpy silt. red-brown, ji^llov or olive-pray. E°€)aS?l Hooks in silt. Fig. 5.—Diagrammatic sketch showing distribution and arrangement of soillayers in lyatayet Valley. Ancient podzol is preserved in areas where it waslater covered with a layer of silt (left) but has been destroyed by later soil-forming processes elsewhere (right). Left side of section is approximately 4feet high. soil at lyatayet. The buried soil profile records a period of relativelywarm climate and soil stability after the filling of the valley with theunderlying congeliturbate and preceding the deposition of the over-lying sandy silt during cold periods. The sandy silt that overlies the buried podzol is similar in size gradeand mineral composition to the matrix of the congeliturbate, but it isfree of large rock fragments. Locally it is laminated; the laminaeare contorted and range from one-eighth to one-half inch in thickn
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