Bedrock landsliding and fluvial landscape evolution: a field perspective

Anne E. Mather, Laura Evenstar, M. Stokes, James Griffiths, Adrian Hartley

Research output: Contribution to conferenceAbstract

Abstract

Bedrock landsliding is a common landscape process in moderate-high relief landscapes, particularly dryland areas, and yet is often overlooked in terms of its role in landscape evolution. This may be due to mis-interpretation/lack of recognition of older events (and thus under-representation) within the Quaternary record, mainly due to the loss of distinctive morphology by erosion post-emplacement, or due to the compound nature of some landslide complexes. Most commonly, fluvial systems are portrayed as the drivers of hillslope processes, yet conversely there is increasing evidence that hillslope processes such as landsliding can have a significant long-term (104-106 yr) impact on channel and hillslope morphology, and thus associated fluvial landscape processes and evolution. For example the early phases of mountain growth are commonly associated with river gorge incision into uplifting areas, and subsequent expansion by landsliding (a consequence of slope oversteepening increasing stress on slopes, weathering reducing shear strength, and excess porewater pressures generated along discontinuity surfaces during seismic events or periods of high intensity rainfall). The topographic signature of that landsliding (in scars and deposits) will impact upon the associated developing fluvial system, often persisting over long (104-106 year) timescales within the landscape.

Within fluvial catchments the status of bedrock landsliding as a landscape evolution process will vary as a function of environmental factors such as climate, seismic activity, local topographic relief and attitude of the bedrock geology. Landslides may facilitate catchment expansion via drainage re-routing through capture between (and within) catchments. The landslides may influence upstream areas through the generation of new local base levels and the creation of new lacustrine environments. Downstream of landslides catchments may be impacted by significant changes in sediment flux (both suspended and bedload), as a result of direct sediment supply from the landslide itself, and landslide lake outburst flooding and flushing of upstream fines.

Through a series of field examples we will examine the role of landsliding at different landscape scales across the dryland spectrum from semi-arid (inter-montane sedimentary basin SE Spain; High Atlas Mountains, Morocco) to hyper-arid (Coastal and PreCordillera of the Atacama Desert, Northern Chile). Such examples can inform our approach to landscape evolution modeling.
Original languageEnglish
Publication statusPublished - 2019
EventINQUA XVII Congress - Cairns
Duration: 1 Jan 2007 → …

Conference

ConferenceINQUA XVII Congress
Period1/01/07 → …

Fingerprint

landscape evolution
landslide
bedrock
hillslope
catchment
relief
mountain
lacustrine environment
bedload
precipitation intensity
gorge
routing
flushing
outburst
atlas
sedimentary basin
shear strength
sediment
discontinuity
porewater

Cite this

Mather, A. E., Evenstar, L., Stokes, M., Griffiths, J., & Hartley, A. (2019). Bedrock landsliding and fluvial landscape evolution: a field perspective. Abstract from INQUA XVII Congress, .
Mather, Anne E. ; Evenstar, Laura ; Stokes, M. ; Griffiths, James ; Hartley, Adrian. / Bedrock landsliding and fluvial landscape evolution : a field perspective. Abstract from INQUA XVII Congress, .
@conference{5f49db9294c2497b8b15f83a1351364a,
title = "Bedrock landsliding and fluvial landscape evolution: a field perspective",
abstract = "Bedrock landsliding is a common landscape process in moderate-high relief landscapes, particularly dryland areas, and yet is often overlooked in terms of its role in landscape evolution. This may be due to mis-interpretation/lack of recognition of older events (and thus under-representation) within the Quaternary record, mainly due to the loss of distinctive morphology by erosion post-emplacement, or due to the compound nature of some landslide complexes. Most commonly, fluvial systems are portrayed as the drivers of hillslope processes, yet conversely there is increasing evidence that hillslope processes such as landsliding can have a significant long-term (104-106 yr) impact on channel and hillslope morphology, and thus associated fluvial landscape processes and evolution. For example the early phases of mountain growth are commonly associated with river gorge incision into uplifting areas, and subsequent expansion by landsliding (a consequence of slope oversteepening increasing stress on slopes, weathering reducing shear strength, and excess porewater pressures generated along discontinuity surfaces during seismic events or periods of high intensity rainfall). The topographic signature of that landsliding (in scars and deposits) will impact upon the associated developing fluvial system, often persisting over long (104-106 year) timescales within the landscape. Within fluvial catchments the status of bedrock landsliding as a landscape evolution process will vary as a function of environmental factors such as climate, seismic activity, local topographic relief and attitude of the bedrock geology. Landslides may facilitate catchment expansion via drainage re-routing through capture between (and within) catchments. The landslides may influence upstream areas through the generation of new local base levels and the creation of new lacustrine environments. Downstream of landslides catchments may be impacted by significant changes in sediment flux (both suspended and bedload), as a result of direct sediment supply from the landslide itself, and landslide lake outburst flooding and flushing of upstream fines. Through a series of field examples we will examine the role of landsliding at different landscape scales across the dryland spectrum from semi-arid (inter-montane sedimentary basin SE Spain; High Atlas Mountains, Morocco) to hyper-arid (Coastal and PreCordillera of the Atacama Desert, Northern Chile). Such examples can inform our approach to landscape evolution modeling.",
author = "Mather, {Anne E.} and Laura Evenstar and M. Stokes and James Griffiths and Adrian Hartley",
year = "2019",
language = "English",
note = "INQUA XVII Congress ; Conference date: 01-01-2007",

}

Mather, AE, Evenstar, L, Stokes, M, Griffiths, J & Hartley, A 2019, 'Bedrock landsliding and fluvial landscape evolution: a field perspective' INQUA XVII Congress, 1/01/07, .

Bedrock landsliding and fluvial landscape evolution : a field perspective. / Mather, Anne E.; Evenstar, Laura; Stokes, M.; Griffiths, James; Hartley, Adrian.

2019. Abstract from INQUA XVII Congress, .

Research output: Contribution to conferenceAbstract

TY - CONF

T1 - Bedrock landsliding and fluvial landscape evolution

T2 - a field perspective

AU - Mather, Anne E.

AU - Evenstar, Laura

AU - Stokes, M.

AU - Griffiths, James

AU - Hartley, Adrian

PY - 2019

Y1 - 2019

N2 - Bedrock landsliding is a common landscape process in moderate-high relief landscapes, particularly dryland areas, and yet is often overlooked in terms of its role in landscape evolution. This may be due to mis-interpretation/lack of recognition of older events (and thus under-representation) within the Quaternary record, mainly due to the loss of distinctive morphology by erosion post-emplacement, or due to the compound nature of some landslide complexes. Most commonly, fluvial systems are portrayed as the drivers of hillslope processes, yet conversely there is increasing evidence that hillslope processes such as landsliding can have a significant long-term (104-106 yr) impact on channel and hillslope morphology, and thus associated fluvial landscape processes and evolution. For example the early phases of mountain growth are commonly associated with river gorge incision into uplifting areas, and subsequent expansion by landsliding (a consequence of slope oversteepening increasing stress on slopes, weathering reducing shear strength, and excess porewater pressures generated along discontinuity surfaces during seismic events or periods of high intensity rainfall). The topographic signature of that landsliding (in scars and deposits) will impact upon the associated developing fluvial system, often persisting over long (104-106 year) timescales within the landscape. Within fluvial catchments the status of bedrock landsliding as a landscape evolution process will vary as a function of environmental factors such as climate, seismic activity, local topographic relief and attitude of the bedrock geology. Landslides may facilitate catchment expansion via drainage re-routing through capture between (and within) catchments. The landslides may influence upstream areas through the generation of new local base levels and the creation of new lacustrine environments. Downstream of landslides catchments may be impacted by significant changes in sediment flux (both suspended and bedload), as a result of direct sediment supply from the landslide itself, and landslide lake outburst flooding and flushing of upstream fines. Through a series of field examples we will examine the role of landsliding at different landscape scales across the dryland spectrum from semi-arid (inter-montane sedimentary basin SE Spain; High Atlas Mountains, Morocco) to hyper-arid (Coastal and PreCordillera of the Atacama Desert, Northern Chile). Such examples can inform our approach to landscape evolution modeling.

AB - Bedrock landsliding is a common landscape process in moderate-high relief landscapes, particularly dryland areas, and yet is often overlooked in terms of its role in landscape evolution. This may be due to mis-interpretation/lack of recognition of older events (and thus under-representation) within the Quaternary record, mainly due to the loss of distinctive morphology by erosion post-emplacement, or due to the compound nature of some landslide complexes. Most commonly, fluvial systems are portrayed as the drivers of hillslope processes, yet conversely there is increasing evidence that hillslope processes such as landsliding can have a significant long-term (104-106 yr) impact on channel and hillslope morphology, and thus associated fluvial landscape processes and evolution. For example the early phases of mountain growth are commonly associated with river gorge incision into uplifting areas, and subsequent expansion by landsliding (a consequence of slope oversteepening increasing stress on slopes, weathering reducing shear strength, and excess porewater pressures generated along discontinuity surfaces during seismic events or periods of high intensity rainfall). The topographic signature of that landsliding (in scars and deposits) will impact upon the associated developing fluvial system, often persisting over long (104-106 year) timescales within the landscape. Within fluvial catchments the status of bedrock landsliding as a landscape evolution process will vary as a function of environmental factors such as climate, seismic activity, local topographic relief and attitude of the bedrock geology. Landslides may facilitate catchment expansion via drainage re-routing through capture between (and within) catchments. The landslides may influence upstream areas through the generation of new local base levels and the creation of new lacustrine environments. Downstream of landslides catchments may be impacted by significant changes in sediment flux (both suspended and bedload), as a result of direct sediment supply from the landslide itself, and landslide lake outburst flooding and flushing of upstream fines. Through a series of field examples we will examine the role of landsliding at different landscape scales across the dryland spectrum from semi-arid (inter-montane sedimentary basin SE Spain; High Atlas Mountains, Morocco) to hyper-arid (Coastal and PreCordillera of the Atacama Desert, Northern Chile). Such examples can inform our approach to landscape evolution modeling.

M3 - Abstract

ER -

Mather AE, Evenstar L, Stokes M, Griffiths J, Hartley A. Bedrock landsliding and fluvial landscape evolution: a field perspective. 2019. Abstract from INQUA XVII Congress, .