Borehole deformation measurements and internal structure of some rock glaciers in Switzerland

Arenson, Lukas U.; Hoelzle, Martin; Springman, Sarah M.

doi:10.1002/ppp.414

Cited by 250 publications

(395 citation statements)

References 30 publications

Supporting

Mentioning

345

Contrasting

Unclassified

Order By: Relevance

“…The stratigraphic characteristics of all boreholes available on Murtèl rock glacier are similar, in BH 2/87 (located 50 m upslope from the upper end of the survey line) the following structure was encountered at successively greater depths: 0-3 m -large boulders and air-filled voids, 3-15 m -an ice-rich layer, 15-30 m -a mixture of ice and sand, 30-52 m -a mixture of sands and boulders and bedrock below (Vonder Mühll and Holub, 1992;Arenson et al, 2002). As can be seen from Fig.…”

Section: Verification and Interpretationmentioning

confidence: 99%

A new model for estimating subsurface ice content based on combined electrical and seismic data sets

2011

View full text Add to dashboard Cite

Abstract. Detailed knowledge of the material properties and internal structures of frozen ground is one of the prerequisites in many permafrost studies. In the absence of direct evidence, such as in-situ borehole measurements, geophysical methods are an increasingly interesting option for obtaining subsurface information on various spatial and temporal scales. The indirect nature of geophysical soundings requires a relation between the measured variables (e.g. electrical resistivity, seismic velocity) and the actual subsurface constituents (rock, water, air, ice). In this work, we present a model which provides estimates of the volumetric fractions of these four constituents from tomographic electrical and seismic images. The model is tested using geophysical data sets from two rock glaciers in the Swiss Alps, where ground truth information in form of borehole data is available. First results confirm the applicability of the so-called 4-phase model, which allows to quantify the contributions of ice-, water-and air within permafrost areas as well as detecting solid bedrock. Apart from a similarly thick active layer with enhanced air content for both rock glaciers, the two case studies revealed a heterogeneous distribution of ice and unfrozen water within Muragl rock glacier, where bedrock was detected at depths of 20-25 m, but a comparatively homogeneous ice body with only minor heterogeneities within Murtèl rock glacier.

show abstract

Section: Verification and Interpretationmentioning

confidence: 99%

A new model for estimating subsurface ice content based on combined electrical and seismic data sets

2011

View full text Add to dashboard Cite

show abstract

“…Borehole temperature data can also be used to enhance process understanding in combination with other measurements like borehole deformation measurements (Arenson et al, 2002), borehole logging (Scapozza et al, 2015), geophysical methods (e.g. Hauck et al, 2011;Hilbich et al, 2009;Krautblatter and Hauck, 2007;Vonder Mühll et al, 2000) or kinematic monitoring with continuous automatic GPS measurements or sporadically with total stations, differential GPS or terrestrial laser scanning (e.g.…”

Section: Introductionmentioning

confidence: 99%

“…Fischer et al, 2012;Gruber and Haeberli, 2007;Huggel et al, 2010;Krautblatter et al, 2013), rock glacier (e.g. Arenson et al, 2002;Kenner et al, 2014) and talus slope dynamics (e.g. Delaloye and Lambiel, 2005) and in general to natural hazards from permafrost areas (e.g.…”

Section: Introductionmentioning

confidence: 99%

Challenges and solutions for long-term permafrost borehole temperature monitoring and data interpretation

Luethi¹,

Phillips²

2016

Geogr. Helv.

View full text Add to dashboard Cite

Abstract. Long-term borehole temperature monitoring in mountain permafrost environments is challenging under the hostile conditions reigning in alpine environments. On the basis of data measured in the SLF borehole network we show three situations where ground temperature data should be interpreted with caution. (i) Thermistors have the tendency to drift, particularly if exposed to moisture or mechanical strain. This induces apparent warming or cooling, which can be difficult to differentiate from real ground temperature changes. Recalibration of thermistor chains is impossible if they cannot be extracted as a result of borehole deformation in creeping permafrost terrain. A solution using zero-curtain-based detection of drift and correction of data is presented. This method is however limited to the active layer, due to the lack of a reference temperature at greater depth. (ii) In contrast to drift-induced apparent warming, actual warming may be induced by natural processes or by the effects of construction activity. (iii) Control data from neighbouring boreholes are sometimes used to fill data gaps and discern drift -however these data may only underline the strong spatial variability of ground temperatures rather than provide measurement redundancy. A selection of recently observed problems regarding borehole monitoring in a hostile measurement environment are discussed, and advantages and possible drawbacks of various solutions including measurement redundancy or alternate instrumentation are presented.

show abstract

“…the European Commission (EC)-funded Permafrost and Climate in Europe (PACE) project; Harris and others, 2003). It is now recognized that detailed knowledge of the internal structure of permafrost is required for the optimum design of hazard-mitigation measures and for the numerical modeling of the dynamic behavior of permafrost (Arenson andothers, 2002, Kääb andWeber, 2004). Diffusive electromagnetic, geoelectric, seismic and ground-penetrating radar (georadar) techniques have proven to be suitable tools for determining the internal structure of permafrost in many regions.…”

Section: Introductionmentioning

confidence: 99%

Geophysical imaging of alpine rock glaciers

Maurer¹,

Hauck

2007

J. Glaciol.

128

View full text Add to dashboard Cite

ABSTRACT. Slope instabilities caused by the disappearance of ice within alpine rock glaciers are an issue of increasing concern. Design of suitable counter-measures requires detailed knowledge of the internal structures of rock glaciers, which can be obtained using geophysical methods. We examine benefits and limitations of diffusive electromagnetics, geoelectrics, seismics and ground-penetrating radar (georadar) for determining the depth and lateral variability of the active layer, the distributions of ice and water, the occurrence of shear horizons and the bedrock topography. In particular, we highlight new developments in data acquisition and data analysis that allow 2-D or even 3-D structures within rock glaciers to be imaged. After describing peculiarities associated with acquiring appropriate geophysical datasets across rock glaciers and emphasizing the importance of state-of-the-art tomographic inversion algorithms, we demonstrate the applicability of 2-D imaging techniques using two case studies of rock glaciers in the eastern Swiss Alps. We present joint interpretations of geoelectric, seismic and georadar data, appropriately constrained by information extracted from boreholes. A key conclusion of our study is that the different geophysical images are largely complementary, with each image resolving a different suite of subsurface features. Based on our results, we propose a general template for the cost-effective and reliable geophysical characterization of mountain permafrost.

show abstract

Borehole deformation measurements and internal structure of some rock glaciers in Switzerland

Cited by 250 publications

References 30 publications

A new model for estimating subsurface ice content based on combined electrical and seismic data sets

A new model for estimating subsurface ice content based on combined electrical and seismic data sets

Challenges and solutions for long-term permafrost borehole temperature monitoring and data interpretation

Geophysical imaging of alpine rock glaciers

Contact Info

Product

Resources

About