Large sackung along major tectonic features in the Central Italian Alps

Deep-seated gravitational slope deformation (sackung) is common in alpine mountain belts. It is controlled by lithological, geomorphological, and structural features. We describe and discuss five examples of DSGSD along the Insubric Line (Periadriatic Fault) in the Central Italian Alps. The five examples are different in morphology, size, state of activity, and distribution, and are located along both primary and secondary valleys. We demonstrate relations between structural and gravitational features and discuss the possibility that structural has both passive and active roles in sackung development. Analysis of PS–SAR data shows that the studied examples are not active today. Numerical modelling demonstrates the importance of lithological and structural constraints, postglacial debuttressing, groundwater fluctuations, and weathering on sackung triggering and development.

[1]  Andreas Meier The Periadriatic fault system in Valtellina (N-Italy) and the evolution of the southwestern segment of the Eastern Alps , 2003 .

[2]  A. Bistacchi,et al.  Mapping tectono-metamorphic histories in the Lake Como basement (Southern Alps, Italy) , 2002 .

[3]  Carlo Colesanti,et al.  Ground deformation monitoring in the Ranafjord area of Norway by means of the permanent scatterers technique , 2002, IEEE International Geoscience and Remote Sensing Symposium.

[4]  Daniel J. Miller,et al.  Topographic perturbations of regional stresses and consequent bedrock fracturing , 1996 .

[5]  Fabio Rocca,et al.  Multibaseline phase unwrapping for INSAR topography estimation , 2001 .

[6]  Fabio Rocca,et al.  Multibaseline InSAR DEM reconstruction: the wavelet approach , 1999, IEEE Trans. Geosci. Remote. Sens..

[7]  Giovanni B. Crosta,et al.  Structural constraints on deep-seated slope deformation kinematics , 2001 .

[8]  D. V. Husen LGM and late-glacial fluctuations in the Eastern Alps , 1997 .

[9]  T. Mahr Deep—Reaching gravitational deformations of high mountain slopes , 1977 .

[10]  Ulf Zischinsky,et al.  On the deformation of high slopes , 1966 .

[11]  H. S. Swolfs,et al.  Gravitational stresses in long symmetric ridges and valleys , 1985 .

[12]  E. Bromhead,et al.  Landslides : in research, theory and practice : Proceedings of the 8th International Symposium on Landslides held in Cardiff on 26-30 June 2000 , 2000 .

[13]  F. Forcella The Sackung between Mount Padrio and Mount Varadega, Central Alps, Italy : a remarkable example of slope gravitational tectonics , 1984 .

[14]  M. Bovis ROCK-SLOPE DEFORMATION AT AFFLICTION CREEK, SOUTHERN COAST MOUNTAINS, BRITISH-COLUMBIA , 1990 .

[15]  D. M. Cruden,et al.  Exhaustion and steady state models for predicting landslide hazards in the Canadian Rocky Mountains , 1993 .

[16]  G Crosta,et al.  Landslide, spreading, deep seated gravitational deformation: analysis, examples, problems and proposals , 1997 .

[17]  Masahiro Chigira,et al.  Long-term gravitational deformation of rocks by mass rock creep , 1992 .

[18]  H. Laubscher Large-scale, thin-skinned thrusting in the southern Alps: Kinematic models , 1985 .

[19]  D. Florineth Surface geometry of the Last Glacial Maximum (LGM) in the southeastern Swiss Alps (Graubünden) and its paleoclimatological significance , 1998 .

[20]  John C. Curlander,et al.  Synthetic Aperture Radar: Systems and Signal Processing , 1991 .

[21]  D. H. Radbruch-Hall Gravitational Creep of Rock Masses on Slopes , 1978 .

[22]  W. Z. Savage,et al.  Topographic and structural conditions in areas of gravitational spreading of ridges in the Western United States , 1989 .

[23]  Fabio Rocca,et al.  Permanent scatterers in SAR interferometry , 1999, Remote Sensing.

[24]  U. Zischinsky Über Sackungen , 1969 .

[25]  Giovanni B. Crosta,et al.  MONITORING AND ASSESSING THE STATE OF ACTIVITY OF SLOPE INSTABILITIES BY THE PERMANENT SCATTERERS TECHNIQUE , 2006 .

[26]  M. Bovis,et al.  Uphill-facing (antislope) scarps in the Coast Mountains, southwest British Columbia , 1982 .

[27]  Fabio Rocca,et al.  Nonlinear subsidence rate estimation using permanent scatterers in differential SAR interferometry , 2000, IEEE Trans. Geosci. Remote. Sens..

[28]  W. Z. Savage,et al.  Mechanics of gravitational spreading of steep-sided ridges («sackung») , 1987 .