Soil Development in Till of Various Ages in Northeastern Pennsylvania

Abstract

Eleven well-drained soils formed in till parent materials of varying ages in northeastern Pennsylvania were studied to determine changes in the soils with time. Four profiles (three Lackawanna and one Bath) were formed in Woodfordian till (15,000 yr B.P.), and two (Leck Kill) were formed in Altonian till (>28,000, <75,000 yr B.P.). The remaining five (Allenwood) were formed in pre-Wisconsinan till (>75,000 yr B.P.). In these soils, the extractable iron oxide, extractable aluminum oxide, and kaolinite contents increase with age, as do the total clay and fine/total clay ratio. With increasing age, the maximum accumulation of these constituents is found deeper in the profile. The extractable silicon oxide distribution is constant with depth, but it decreases in overall amount with time. Gibbsite is found only in small amounts in the A horizon of Altonian soils, but occurs throughout the profile of pre-Wisconsinan soils, although only in small amounts. In general, differences were found in these soils which separated them into three groups representing varying degrees of soil development. A regression equation was derived to predict the age of soils formed from the Altonian till based on a “clay accumulation index” value for soils of known Woodfordian and Holocene ages. The equation log Y = 1.80 + 0.992(logX) best fit the data, with an r2 value of 0.913. Using this equation, a mean age of 41,000 yr was calculated for the Altonian soils. This date was used to derive a second equation to predict ages for pre-Wisconsinan soils. The equation with the highest r2 value (0.934) was log Y = 1.81 + 0.998(logX). Dates for soils developed in the White Deer till and the Laurelton till of the pre-Wisconsinan stage were calculated to be 86,000 and 91,000 yr B.P., respectively. These dates fall within ages estimated for the Sangamon Interglaciation and thus would appear to be too young for pre-Sangamonian materials. The probable reason for the “too-young age” is that the C-horizon material of the pre-Wisconsinan soils was weathered and did not provide an accurate estimate of clay accumulation for the prediction equation.

Distributions of Radionuclides (U & Th) and Pedogenic Characteristics as Indicators of Wet and Warm Climate during the Holocene in the Western Part of the Upper Gangetic Plain, India

“…Clay accumulation index (sum of increase in clay content over that of A or C-horizon multiplied by thickness of B-sub-horizon/s, C.A.I. index) proposed by Levine and Ciolkosz (1983) was also calculated for typical pedons. Where trenches were excavated up to C-Horizons, the clay percentages were calculated taking the clay abundances of C-horizon into account as C-horizon is least affected by pedogenic processes.…”

Soil Development in Quaternary Glacial Deposits, Waterton Park Area, Southwestern Alberta

“…The Harden profile index (HPI) is based on relative development of field properties, including horizon thickness, texture, structure, consistence, rubification, pH, and clay films (Harden, 1982). Clay accumulation index (CAI) is a measure of argillic horizon development and equals ^(Bc-Cc) X T), where Bc is % clay in Bt horizons, Cc is % clay in C horizons, and T is thickness of Bt horizon(s) (Levine and Ciolkosz, 1983).…”

“…1982); f) maximum clay film index (Harden, 1982); g) Harden profile index (Harden, 1982); h) clay accumulation index (Levine and Ciolkosz, 1983); i) depth of leaching of calcium carbonate. Data from Coen andHolland (1974.…”

Fabric, paleomagnetism, and interpretation of pre-illinoian diamictons and paleosols on Cloudy Ridge and Milk River Ridge, Alberta and Montana

“…Relative development of the paleosols is compared with modern soils using profile-development (Harden, 1982) and clay-accumulation indices (Levine and Ciolkosz, 1983). Classification of paleosols can be problematic due to the possibility of post-burial diagenetic alterations.…”

“…It is slightly acidic, with pH values ranging from 6.3 to 6.9. Rubification in the Bt horizon to yellowish red (5YR 5/8 moist) and strong brown (7.5YR 5/6 moist) colors coincides (Harden, 1982) g-CAI = clay accumulation index (Levine and Ciolkosz, 1983) with relatively high concentrations (1.98 %) of dithioniteextractable free iron and a relatively high percentage (48) of weathered clasts and "ghost stones". The underlying 242-cmthick, cambic (Bw) horizon is slightly less oxidized and has lower concentrations of clay (10 to 16 %), free iron (1.47 %), and weathered clasts (23 %).…”