Giorgio Poretti

First steps towards a landslide inventory map of the Central Karakoram National Park

Abstract The northeastern part of Pakistan is known to be a region of extremes, where the highest reliefs and the longest glaciers of the world may be found. In this environment, through the multidisciplinary Social, Economic and Environmental Development (SEED) Project the knowledge of the sustainable exploitation possibilities of the Central Karakoram National Park area (CKNP) will be improved. One of this projects objectives is the analysis of the geological hazards giving as output a landslide inventory and a susceptibility map, utilizable as functional tools for a future sustainable territorial planning. The Bagrot Valley, chosen as test site, was partially field surveyed and part of the landslide-prone areas preliminarily identified through DEM analysis, GIS techniques and Analytical Hierarchy Process (AHP) methodology, were later validated on the field. ASTER DEM was used as the basis of morphometric analysis.

Spectral techniques for the analysis of tidal time series

SummaryThree different methods are given for the Fourier analysis of time series leading to the determination of high reliable values of frequencies, amplitudes and phases of the inherent components. For two methods the hypothesis is made that the time series is sufficiently long to separate very close components, while for the third the frequencies are supposed to be given. Two of these methods have been applied to a time series obtained by sampling an artificial tidal function.

Landslide Susceptibility Analysis in Arandu Area Shigar Valley, CKNP (Gilgit-Baltistan- Pakistan)

The Pakistani Gilgit-Baltistan are recognised as being one of the most beautiful and interesting places in the world due to the presence of the longest glaciers and the highest reliefs. This area remained remote and inaccessible before 1965, after which began the construction of the first roads (Karakoram Highway—KKH). In 1992, the Pakistani Government delegated the responsibility for initiating a preliminary survey to outline the borders of the Central Karakoram National Park (CKNP) which allowed a preliminary outline of the borders (about 3000 km2) where the major mountain massifs (as Mt. K2), watersheds, and glaciers were included. Since then, several proposals followed. With the aim of preserving this natural beauty for future generations as well as providing the CKNP of a Management Plan, a 5-year multidisciplinary project called SEED (Social, Economic, Environmental Development) started. One of the project’s objectives was the analysis of the landslide geohazards aiming at the implementation of a landslide inventory and the realization of a susceptibility map. The Arandu village and its surroundings, which is part of Shigar valley, where the Chogolungma glacier is, was chosen as pilot area. During the summer survey had in 2012, part of the landslide-prone areas, previously identified through DEM analysis (derived from ASTER and Remote Sensing (RS) images) and GIS techniques were identified validating the obtained maps. The Analytical Hierarchy Process (AHP) was used to extract the factor weights in a pairwise comparison matrix. Frequency ratio (FR) method was adopted to drive each class weight. The Weighted linear combination was used in the end to determine the landslide susceptibility index value (LSI).

An example of active DSGSD in the Carnian Alps (NE Italy)

In the northern part of Friuli Venezia Giulia Region (Italy), in the Carnic Alps, above the Cercevesa stream, an active mass movement has been recently identified and classified as Deep Seated Gravitational Slope Deformation (DSGSD). The phenomenon covers an area of about 0.5 km2 and involves limestones overlying sandstones and mudstones. The most evident morphological feature of the Cercevesa DSGSD is a double-crested ridge on the top of the slope. The first measurements, recorded since June 2008, show a constant opening rate of about 58 cm/yr, a really rare value for gravitational phenomena in the Alps. To detect the triggering factor, geomorphological data, meteorological time series (rainfall, snowfall and temperature) and seismological data have been analyzed. The comparative analysis highlighted that the persistent rainfall of mid-November 1990 can be identified as the root cause of the phenomenon.

Gravity anomalies in North-Eastern Afghanistan and on the Pamirs syntaxis

During a survey carried out in Afghanistan in 1964 under the leadership of Prof. A. Desio, Prof. Antonio Marussi measured 64 gravity stations along profiles crossing several regions of the country. These data are published now and their meaning is explained within the context of the other gravity data available on the region including the Hindu Kush, the Karakorum mountain ranges up to the Pamirs plateau.RiassuntoDurante una spedizione effettuata in Afghanistan nel 1964, sotto la guida del Prof. Ardito Desio, il Prof. Antonio Marussi ha misurato i valori di gravita in 64 stazioni lungo profili che attraversano diverse regioni del paese. Questi dati vengono ora pubblicati e ne viene esaminato il significato nel contesto degli altri dati gravimetrici disponibili nella regione che va dal Hindu Kush al Karakorum e si estende fino all’altopiano del Pamir.