Richard Waller | Keele University (original) (raw)

Papers by Richard Waller

… 2010, held 2-7 May …, 2010

The UK's Higher Education Academy Subject Centre for Geography, Earth and Environmental Scie... more The UK's Higher Education Academy Subject Centre for Geography, Earth and Environmental Sciences (GEES) is currently running a project entitledC-Change in GEES: Open licensing of climate change and sustainability resources in the Geography, Earth ...

The geomorphological processes operating within landscape systems result in the erosion, transpor... more The geomorphological processes operating within landscape systems result in the erosion, transport and deposition of significant quantities of sediment that can be preserved within a range of depositional landforms. The processes of sediment transport can result in the material acquiring a series of distinctive characteristics. Material deposited within a beach environment for example is well known for its highly rounded nature. These distinctive characteristics can be used to interpret the processes responsible for the deposition of sediments of unknown origin.

Proceedings of the 9th International Conference on Learning Analytics & Knowledge

Current Learning Analytics (LA) systems are primarily designed with University staff members as t... more Current Learning Analytics (LA) systems are primarily designed with University staff members as the target audience; very few are aimed at students, with almost none being developed with direct student involvement and undertaking a comprehensive evaluation. This paper describes a HEFCE funded project that has employed a variety of methods to engage students in the design, development and evaluation of a student facing LA dashboard. LA was integrated into the delivery of 4 undergraduate modules with 169 student sign-ups. The design of the dashboard uses a novel approach of trying to understand the reasons why students want to study at university and maps their engagement and predicted outcomes to these motivations, with weekly personalised notifications and feedback. Students are also given the choice of how to visualise the data either via a chart-based view or to be represented as themselves. A mixed-methods evaluation has shown that students' feelings of dependability and trust of the underlying analytics and data is variable. However, students were mostly positive about the usability and interface design of the system and almost all students once signed-up did interact with their LA. The majority of students could see how the LA system could support their learning and said that it would influence their behaviour. In some cases, this has had a direct impact on their levels of engagement. The main contribution of this paper is the transparent documentation of a User Centred Design approach that has produced forms of LA representation, recommendation and interaction design that go beyond those used in current similar systems and have been shown to motivate students and impact their learning behaviour. CCS CONCEPTS • Human-centered computing → Visualization application domains; HCI design and evaluation methods.

The Cryosphere Discussions

This study suggests that cold-ice processes may be more widespread even within temperate glacial ... more This study suggests that cold-ice processes may be more widespread even within temperate glacial systems, than previously assumed. We present the first direct observations of cold-ice at the snout of the temperate glacier Midtdalsbreen an 20 outlet of the Hardangerjøkulen icefield (Norway) from 43 line-kilometres of ground penetrating radar data. Results show a 40 m-wide cold-ice zone within the majority of the glacier snout, where ice thickness is <10 m. We interpret ice to be frozen to its bed across this zone, consistent with basal freeze-on processes involved in the deposition of minor moraines. We also find at least two zones of cold-ice up to 15 m thick within the ablation area, occasionally extending to the glacier bed. There are two further zones of cold-ice up to 30 m thick in the accumulation area, also extending to the glacier bed. Cold-ice zones in 25 the ablation area tend to correspond to areas of the glacier that are covered by late-lying seasonal snow patches that reoccur over multiple years. Parts of the glacier frozen to the bed occur up-glacier from controlled moraines, and this basal thermal state likely exert control on moraine formation and location. We hypothesise that basal freeze-on may also influence glacier dynamics via increased lateral drag, and may become particularly important in forthcoming decades with i) continued thinning of Hardangerjøkulen and ii) retreat of Midtdalsbreen to higher altitudes where basal freeze-on could become more widespread. 30 Adversely, the number and size of late-lying snow patches in the ablation area may decrease reducing the extent of cold-ice.

Permafrost and Periglacial Processes

Journal of Glaciology

This paper examines the debris-rich basal ice layer from Worthington Glacier, Alaska, U.S.A., a s... more This paper examines the debris-rich basal ice layer from Worthington Glacier, Alaska, U.S.A., a small valley glacier overlying rigid bedrock. The debris-rich basal ice layer studied shows evidence for large-scale longitudinal compressive deformation (isoclinal folds and nappes), similar in style and magnitude features to that reported from push moraines formed in glacial sediments. The debris-rich ice largely comprisedstratified solid ice(layers of alternating debris-rich and debris-poor ice) which we suggest results from the tectonic attenuation of folds produced from the deformation of the frozen debris, glacier ice and bubble-rich ice that comprise the initial basal layer of Worthington Glacier. Beneath the glacier lies a thin bed of saturated diamicton which contains evidence of limited movement. It is suggested that this is the result of the partial melt-out of the debris-rich basal ice layer which then behaved as a local (and seasonal) thin deforming layer.It is suggested that...

Provided by NERC Open Research Archive 3. Key Characteristics 3.1 Stratigraphical context and spa... more Provided by NERC Open Research Archive 3. Key Characteristics 3.1 Stratigraphical context and spatial distribution The sand intraclasts occur within a mélange facies that includes remobilised elements of the Bacton Green Till Member (BGTM), the Happisburgh Till Member (HTM), preglacial sands and gravels

Glacier Science and Environmental Change, 2006

Recent advances in our understanding of glacier-permafrost interactions provide an alternative hy... more Recent advances in our understanding of glacier-permafrost interactions provide an alternative hypothesis to interpret Pleistocene glaciotectonic sequences in regions where permafrost no longer exists. Instead of necessarily forming under unfrozen subglacial conditions, some glaciotectonic sequences may have formed by submarginal deformation of warm, partially-frozen permafrost. An example from North Norfolk, U.K., suggests that an ice sheet during Marine Isotope Stage 12 advanced across permafrost terrain, deforming it beneath the margin. Such a scenario can help explain some features whose formation under unfrozen conditions is problematic, including (1) the substantial thickness of the deforming layer and (2) the preservation of stratified intraclasts. Accordingly, glacial geologists should remain open to the possibility of glacier-permafrost interactions when interpreting glacigenic sequences. Such a re-interpretation could have major implications for reconstructing basal thermal regimes and modeling palaeo-ice sheets.

Sedimentary Geology, 2012

Glaciers and permafrost represent key components of the global cryosphere. Widely held assumption... more Glaciers and permafrost represent key components of the global cryosphere. Widely held assumptions that: (1) they are largely mutually exclusive and, (2) glaciers resting on permafrost are slow moving and geomorphologically ineffectual has meant that glacier-permafrost interactions have been given little attention within the research literature. Recent research, however, has demonstrated that such interactions are likely to have been more extensive than previously thought, particularly during periods of ice-sheet growth when glaciers would have advanced over pre-existing permafrost. Work in both modern and ancient environments has revealed that subglacial processes such as basal sliding and subglacial sediment deformation can remain active at temperatures below the pressure melting point due to the persistence of premelted liquid water. Consequently, cold-based glaciers resting on permafrost are potentially more dynamic than previously thought and are capable of creating subglacial features typically viewed as only forming beneath warm-based ice. In addition, the active coupling of cold-based ice with ice-marginal permafrost means such ice masses are capable of deforming sediments and occasionally bedrock to depths of tens or even hundreds of meters and are commonly associated with the development of a range of distinctive ice-marginal landforms including push or thrust moraines and hummocky

Sedimentary Geology, 2004

Using a combination of geological and geophysical techniques (Ground Penetrating Radar), we explo... more Using a combination of geological and geophysical techniques (Ground Penetrating Radar), we explore the tectonic architecture of a push moraine formed just after the 1890 Neoglacial ice maximum of Hagafellsjfkull-Eystri, in central Iceland. The push moraine formed by a re-advance, perhaps a surge, of the glacier against a moraine bank-delta sometime between 1890 and 1929. Different tectonic architectures exist in two adjacent parts of the same push moraine complex. In one location, the ice advance pushed the delta pro-glacially to form a prominent single-crested push moraine. Deformation occurred along a single listric décollement over which a large nappe moved, as a result of ice-marginal pushing. In an adjacent location, the ice-margin mounted and advanced over the ice-contact delta to create a push moraine at the limit of the advance by subglacial gravityspreading. In this case, deformation occurred along a series of listric thrusts and by folding within the distal parts of the overridden delta. The geomechanical causes of these two contrasting styles of deformation, present in adjacent sectors of the same ice-marginal flow unit, are discussed and a range of possible controls identified. These include variation along the former icemargin and foreland in: (1) glacier-foreland coupling; (2) foreland shear strength; and (3) the frictional characteristics of the décollement. Some combination of these variables provides the most likely cause. The case study presented in this paper provides an example of the potential for rapid variation in the tectonic architecture of a push moraine along strike.

Quaternary Science Reviews, 2005

Glacially-deformed massive ice and icy sediments (MI-IS) in the Eskimo Lakes Fingerlands and Summ... more Glacially-deformed massive ice and icy sediments (MI-IS) in the Eskimo Lakes Fingerlands and Summer Island area of the Tuktoyaktuk Coastlands, western Arctic Canada, show, in the same stratigraphic sequences, features characteristic of both basal glacier ice and intrasedimental ice. Basal-ice features comprise (1) ice facies and facies groupings similar to those from the basal ice layers of contemporary glaciers and ice sheets in Alaska, Greenland and Iceland; (2) ice crystal fabrics similar to those from basal ice in Antarctica and ice-cored moraines on Axel Heiberg Island, Canada; and (3) a thaw or erosional unconformity along the top of the MI-IS, buried by glacigenic or aeolian sediments. Intrasedimental ice consists of pore ice and segregated ice formed within Pleistocene sands deposited before glacial overriding. The coexistence of basal and intrasedimental ice within the MI-IS records their occurrence within the basal ice layer of the Laurentide Ice Sheet. Stagnation of the ice sheet and melt-out of till from the ice surface allowed burial and preservation of the basal ice layer on a regional scale. The widespread occurrence of supraglacial melt-out till with clast fabrics similar to those in the underlying ice suggests that such till can be well preserved during partial thaw of a continental ice sheet in lowlands underlain by continuous permafrost. Article Outline 2.2. Massive ice and icy sediments MI-IS are abundant in the Tuktoyaktuk Coastlands. Out of c. 5000 shot holes drilled to depths of usually 15-35 m along seismic lines on Richards Island, Tuktoyaktuk Peninsula and nearby areas (Fig. 1), c. 20-30% of the holes penetrated icy sediments and c. 1-5% penetrated massive ice at any given depth (Rampton and Mackay, 1971). The massive ice averages at least 13 m thick, commonly overlies sand and gravel and underlies clay or pebbly clay (till) (Mackay, 1971). Mackay (1971) attributed most of the massive ice to ice segregation, and Rampton, 1974, Rampton, 1988a and Rampton, 1988b developed this idea into a regional model in which massive ice formed in front of the retreating ice sheet. Rampton (1991) later revised his model to avoid the necessity for water under high pressure to move large distances under thin, aggrading permafrost without rupturing it. In the revised model, the upper c. 50-100 m of permafrost degraded beneath the terminus of the ice sheet (cf. French and Harry, 1990). Then stagnation and thinning of the LIS allowed permafrost to aggrade beneath it and form subglacial massive ice, with water supplied from glacial meltwater. Mackay and Dallimore (1992), however, questioned whether this combination of icesheet stagnation, subglacier water flow and subglacial massive-ice growth occurred contiguously in view of the cold ground temperature (MAGT of perhaps-8C or colder) and time required to grow tens of metres of massive ice (c. 100-500 years). They suggested (p. 1245) other possibilities for the origin of the massive ice, such as "subglacier massive-ice growth beneath stagnant glacier ice of limited areal extent together with pore-water expulsion from permafrost growth in subaerial areas." 2.3. Eskimo Lakes Fingerlands and Kittigazuit Low Hills Glacially-deformed MI-IS well exposed in coastal bluffs were examined in two physiographic regions. The first region, the Eskimo Lakes Fingerlands, occupies the central and northern Eskimo Lakes (Fig. 1; Rampton, 1988a), the `fingers' being arcuate peninsulas interpreted as ice-thrust ridges (Mackay, 1963) or remnant ridges between subglacial meltwater channels (Rampton, 1988a). MI-IS were examined in 1998 and 1999 at fourteen sites in the central Fingerlands (Fig. 2a); at three sections near the `western fingers' (site 15; Fig. 2b), to compare with reports from here by French and Harry (1990); and at one section (site 16) in the `outer fingers' (Fig. 1).

Quaternary International, 2001

Quaternary International, 2012

Proceedings of the Geologists' Association, 2009

ABSTRACT Recent work in modern and ancient glacial environments has demonstrated the ability of c... more ABSTRACT Recent work in modern and ancient glacial environments has demonstrated the ability of cold-based glaciers to interact with permafrost. Geological evidence for glacier–permafrost interactions is revealed in Arctic regions where permafrost has persisted since deglaciation. Whilst similar interactions probably occurred near the margins of former ice sheets in the mid-latitudes, this interpretation is rarely applied to unfrozen glacigenic sequences. This review considers the extent to which this alternative hypothesis can explain two key aspects of the glaciotectonic sequences of North Norfolk that have traditionally been attributed to the deformation of unfrozen sediment. The substantial thickness (&gt;10m) of the pervasively deformed sequences and the preservation of stratified sand intraclasts within them are consistent with deformation at temperatures slightly below the pressure melting point (warm permafrost). Such deformation is also consistent with the pre-glacial environment, which was characterised by continuous permafrost. The hypothesis of deformation at sub-freezing temperatures should be considered more widely when interpreting glaciotectonically deformed, ice-marginal sequences in the mid-latitudes. The application of geological evidence to reconstruct basal thermal regimes beneath former glaciers would complement existing geomorphological inverse models and provide additional information to improve the parameterisation of subglacial processes in numerical ice-sheet models.

Journal of Glaciology, 2004

The upper 20—30 m of ice-rich permafrost at three sites overridden by the northwest margin of the... more The upper 20—30 m of ice-rich permafrost at three sites overridden by the northwest margin of the Laurentide ice sheet in the Tuktoyaktuk Coastlands, western Arctic Canada, comprise massive ice beneath ice-rich diamicton or sandy silt. The diamicton and silt contain (1) truncated ice blocks up to 15 m long, (2) sand lenses and layers, (3) ice veins dipping at 20—30°, (4) ice lenses adjacent and parallel to sedimentary contacts, and (5) ice wedges. The massive ice is interpreted as intrasedimental or buried basal glacier ice, and the diamicton and silt as glacitectonite that has never thawed. Deformation of frozen ground was mainly ductile in character. Deformation was accompanied by sub-marginal erosion of permafrost, which formed an angular unconformity along the top of the massive ice and supplied ice clasts and sand bodies to the overlying glacitectonite. After deformation and erosion ceased, postglacial segregated ice and ice- wedge ice developed within the deformed permafrost.

Geological Society, London, Special Publications, 2005

This paper describes the key characteristics of a proglacial moraine complex at the Leverett Glac... more This paper describes the key characteristics of a proglacial moraine complex at the Leverett Glacier, western Greenland. The presence of a large stream-cut exposure allowed the examination of its internal structure, as well as its surface geomorphology. It is composed of a variety of ice and sediment facies, including debris-poor ice, ice-rich diamicton and ice-rich gravel. These units are glaciotectonized, with the exposure featuring a major fault and associated drag fold, a planar, erosional unconformity, and a variety of small-scale folds. Various interpretations are considered, including the possibility that the sequence represents a buried basal ice layer. However, it is argued that the structural characteristics are best explained by a two-phase model involving ice advance and proglacial or ice-marginal compression, followed by overriding and subglacial deformation and erosion, tentatively related to ice advance after the Holocene Hypsithermal (c. 4900–3000 calendar years bp)....