Electronic Theses and Dissertations

Identifier

4818

Date

2016

Date of Award

11-23-2016

Document Type

Thesis

Degree Name

Master of Science

Major

Earth Sciences

Committee Chair

Mervin Jerry Bartholomew

Committee Member

Dorian Burnette

Committee Member

Arleen Alice Hill

Committee Member

Youngsang Kwon

Abstract

Historical accounts of landslides induced by major storm events (1916, 1996) along the Hickory Nut Gorge near Chimney Rock, North Carolina as well as documented rockfall (2012) along a portion of massive exfoliating cliff faces, and the empirical evidence of enormous boulders scattered throughout the valley show that this part of the Blue Ridge is prone to landslides. With so much tourism due to Chimney Rock State Park and Lake Lure, it is imperative to gain a better understanding of the landslides in the Hickory Nut Gorge. This study is a field-work based multi-methods approach to classify these landslide deposits by type based on observable characteristics and geomorphic form and to discuss the processes by which they form and, in particular, explore the historical storm events as well as other potential causes of landslides near Chimney Rock. Field observations of geomorphic forms, deposit characteristics, and topographic features demonstrate that only two landslides types and processes - rockfall and debris flow are common with debris flow being dominate. Although rockfall dominates along very steep to near-vertical upper slopes and cliffs, differences in deposit characteristics and geomorphology suggest two types: 1) weathering-induced exfoliation and 2) seismicity. Based on observed geomorphic features and weathering characteristics of debris flows, younger debris-flow channels are incised through older debris deposits as well as through terrace deposits, indicating repetitive flow events during flooding. Major storm events occurred in 1916, 1994, 1996, 2008, and 2014 with the 1916 and 1996 events triggering multiple landslides. Antecedent precipitation, including the timing of such precipitation, as well as storm event rainfall duration appear to be the most critical rainfall characteristics which generate landslides in the Hickory Nut Gorge.The most influential factors in the study area appear to be the moderate susceptibility of the Henderson Gneiss, the steep slopes of the gorge, and human activity such as logging.

Comments

Data is provided by the student.

Library Comment

dissertation or thesis originally submitted to the local University of Memphis Electronic Theses & dissertation (ETD) Repository.

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