The sedimentology of the Bloomington fan complex: an element of the Oak Ridges Moraine, Southern Ontario
type: CreativeWork
description: The Oak Ridges Moraine is a major physiographic feature of south-central Ontario, extending from Rice Lake westward to the Niagara Escarpment. While much previous work has largely postulated a relatively simple the origin of the moraine, recent investigations have concentrated on delineating the discernible glacigenic deposits (or landform architectural elements) which comprise the complex mosaic of the Oak Ridges Moraine. This study investigates the sedimentology of the Bloomington fan complex, one of the oldest elements of the Oak Ridges Moraine. The main sediment body of the Bloomington fan complex was deposited during early stages of the formation of the Oak Ridges Moraine, when the ice subdivided, and formed a confined, interlobate lake basin between the northern and southern lobes. Deposition from several conduits produced a fan complex characterized by multiple, laterally overlapping, fan bodies. It appears that the fans were active sequentially in an eastward direction, until the formation of the Bloomington fan complex was dominated by the largest fan fed by a conduit near the northeastern margin of the deposit. Following deposition of the fan complex, the northern and southern ice margins continued to retreat, opening drainage outlets to the west and causing water levels to drop in the lake basin. Glaciofluvial sediment was deposited at this time, cutting into the underlying fan complex. Re-advancing northern ice then closed westerly outlets, and caused water levels to increase, initiating the re-advance of the southern ice. As the southern ice approached the Bloomington fan, it deposited an ice-marginal sediment complex consisting of glacigenic sediment gravity flows, and glaciolacustrine and glaciofluvial sediments exhibiting north and northwesterly paleocurrents. Continued advance of the southern ice, overriding the fan complex, ii produced large-scale glaciotectonic deformation structures, and deposited the Halton Till. The subaqueous fan depositional …
abstract: The Oak Ridges Moraine is a major physiographic feature of south-central Ontario, extending from Rice Lake westward to the Niagara Escarpment. While much previous work has largely postulated a relatively simple the origin of the moraine, recent investigations have concentrated on delineating the discernible glacigenic deposits (or landform architectural elements) which comprise the complex mosaic of the Oak Ridges Moraine. This study investigates the sedimentology of the Bloomington fan complex, one of the oldest elements of the Oak Ridges Moraine. The main sediment body of the Bloomington fan complex was deposited during early stages of the formation of the Oak Ridges Moraine, when the ice subdivided, and formed a confined, interlobate lake basin between the northern and southern lobes. Deposition from several conduits produced a fan complex characterized by multiple, laterally overlapping, fan bodies. It appears that the fans were active sequentially in an eastward direction, until the formation of the Bloomington fan complex was dominated by the largest fan fed by a conduit near the northeastern margin of the deposit. Following deposition of the fan complex, the northern and southern ice margins continued to retreat, opening drainage outlets to the west and causing water levels to drop in the lake basin. Glaciofluvial sediment was deposited at this time, cutting into the underlying fan complex. Re-advancing northern ice then closed westerly outlets, and caused water levels to increase, initiating the re-advance of the southern ice. As the southern ice approached the Bloomington fan, it deposited an ice-marginal sediment complex consisting of glacigenic sediment gravity flows, and glaciolacustrine and glaciofluvial sediments exhibiting north and northwesterly paleocurrents. Continued advance of the southern ice, overriding the fan complex, ii produced large-scale glaciotectonic deformation structures, and deposited the Halton Till. The subaqueous fan depositional …
author: Paterson, Jens Tore.
language: eng
keywords: Moraines--Ontario--Bloomington., Sediments (Geology)--Ontario--Bloomington., Sedimentation and deposition--Ontario--Bloomington.
date published: 1995-07-09T18:54:26Z
date modified: 2026-07-24T01:22:54Z
provider: Brock University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Brock University

PropertyValue
property ID: Handle
value: http://hdl.handle.net/10464/2200