Skip to Main Content
Skip Nav Destination

Abstract

This field guide focuses on glacial history, dynamics and processes, and postglacial landscape adjustments in the southern Fraser Plateau region. Located between the Coast and Columbia Mountains in south-central British Columbia, Canada, the southern Fraser Plateau was near the geographic center of the last (marine oxygen isotope stage [MIS] 2) Cordilleran Ice Sheet (CIS). The transition from cold to warm-based ice during MIS 2 is recorded in till sedimentology and structural geology. The perceived absence of large deglacial recessional moraines has been used as evidence that ice regionally stagnated because of a rapid rise in equilibrium line altitude. However, glacioisostatic rebound orientations, ice-marginal channel and grounding-line and push moraine distributions, and reconstructions of late-glacial ice-marginal lake evolution suggest a systematic northwestward pattern of active ice-margin retreat toward the Coast Mountains, accompanied by regional thinning. Eskers and erosional corridors record drainage of supraglacial lakes or ice-marginal water sources in or over thin ice. Many ice-dammed lakes drained catastrophically. Following lake drainage, streams incised valley fills, leaving behind terraces capped by paraglacial fans and eolian sediment. In sum, we examine (1) valley-fill sediments that record Quaternary history dating back to the early or mid-Pleistocene; (2) till, moraines, erosional corridors, and eskers that provide evidence for MIS 2 CIS dynamics and hydrology; (3) late-glacial ice-marginal lake sediments and landforms that allow reconstruction of lake evolution and drainage, and changing ice-margin positions; and (4) the character and ages of river terraces, paraglacial fans, and eolian sediments that record the timing and nature of postglacial landscape adjustments.

You do not currently have access to this chapter.

Figures & Tables

Contents

References

Related

Citing Books via

Close Modal

or Create an Account

Close Modal
Close Modal