Subaqueous outwash deposits in the Ingraham ridge, Chazy, New York

Abstract

A 1.5 km segment of Ingraham ridge, a stratified sand and gravel ridge in northeastern New York, is composed dominantly of subaqueous outwash deposits. The core of the ridge segment may include subordinate subglacial tunnel deposits. The subaqueous outwash is composed mainly of interbedded sediment gravity flow, bar, dune, and ripple deposits that occur in channels. Sheetlike cross-stratified and cross-laminated deposits also are common, particularly on the distal western margin of the ridge segment. The ridge segment is draped by glaciolacustrine laminated sand, silt, and clay and glaciomarine massive mud. Westward decrease in grain size and scale of sedimentary structures is attributed to confining ice walls of an asymmetric embayment. Sediments are deformed in part by the melting of adjacent and buried ice. The ridge was modified during Champlain Sea regression and the reworked deposits were colonized by shallow-water organisms. Reworking may have been minor, and the broad, low morphology of the ridge may be due to subaqueous outwash deposition along its full length during retreat of the ice margin.

A Basin Analysis of the Wabigoon Area of Lake Agassiz, a Quaternary Clay Basin in Northwerstern Ontario

“…Well-developed, angle-of-repose foresets are indicative of transverse bars, while low-angle foresets are more common on longitudinal or diagonal bars (p. 617). Common alternations on the foresets, of openwork and closed-work gravels, and sands with both up-foreset and down-foreset palaeoflow indicators, represent fluctuating flows (Banerjee and McDonald, 1975;Deimer, 1988), or longitudinal sorting and considerable strength of the return flow in the separation zone downflow of bedforms .…”

“…11). These fans, likely not laterally confined by the ice, still formed significant topographic highs, since rapid flow expansion and loss of competence would have resulted in most of the coarse sediment load being deposited in the immediate vicinity of the tunnel mouth (Rust and Romanelli, 1975;Banerjee and McDonald, 1975;Deimer, 1988) or in a subglacial chamber .…”

Les eskers : essai de synthèse bibliographique

“…Des plis ou des failles peuvent aussi être le résultat de la fonte de culots de glace dans les sédiments (par ex. Rust et Romanelli, 1975 ;Cheel et Rust, 1982;Robison, 1983;Rust, 1987;Diemer, 1988). Enfin, une faille dans un esker au site d'une gravière peut être provoquée lors de l'exploitation (Lahee, 1908).…”

“…Rust et Romanelli, 1975;Rust, 1977Rust, , 1986Rust, 1987Cheel, 1982 ;Cheel et Rust, 1982 ;Robison, 1983Thomas, 1984Diemer, 1988;Sharpe, 1987. Construction d'eskers suivant l'hypothèse de la marge glaciaire : (a) segments deltaï-ques séparés, (b) segments deltaïques superposés (sources : (a) Banerjee et McDonald, 1975, (b) Rust et Romanelli, 1975 Banerjee et McDonald, 1975, (b) Rust et Romanelli, 1975 Thompson, 1989).…”

“…L'ensemble contient souvent des débris rocheux délestés par des glaces flottantes (voir par ex. Cheel, 1982 ;Thomas, 1984;Sharpe, 1987Sharpe, , 1988Diemer, 1988;Spooner et Dalrymple, 1993). Flint (1928), Suttner (1967) et Ruszczynska-Szenajch (1991) ont distingué des formes de remplissage de crevasses des véritables crêtes d'eskers mises en place dans des chenaux d'eau de fonte.…”