FURTHER DEVELOPMENTS ON DIGITAL MODELS IN A CONTROL PROBLEM FOR THE 
"ANCONA '82" LANDSLIDE 
Luigi Colombo*, Gabriele Fangi**, Luigi Mussio*, Fabio Radicioni** 
* Politecnico di Milano 
Milano, Italy 
** Università di Ancona 
Ancona, Italy 
ABSTRACT 
In December 1982, a large scale landslide (+220 ha) has interested the 
district of Ancona (Italy), involving also some residential quarters of 
the city. A working group consisting of geologists, geophysicists, geo- 
technicians and geodesists has been set up in order to analyze the causes, 
to control the ground settling and to determine the consequent destina- 
tion of the area. Inside this working group, the geodesists have perform- 
ed the control surveying by topographic and photogrammetric instruments. 
The former is a still going operation intended to control the settlement 
of the terrain after the landslide, the latter is mainly the study of the 
deformation of the landscape derived from photogrammetric material taken 
before and after the landslide occurrence. The photogrammetric models are 
observed in order to achieve a regular grid of points on the ground. In 
this way it has been possible: 
- to compute the earth settlements; 
- to evaluate the volumes involved; 
- to analyze the shape and the pattern of the break lines; 
- to point out the landslide boundary. 
This paper presents the results obtained in this context. 
FOREWORD 
After the Ancona '82 landslide, some combined studies were carried out 
in order to examine all the possible aspects of the event both from a 
geological and geodetic point of view. In particular the first photogram- 
metric aim was to detect the global movements of the slide. The task was 
performed by means of aerial triangulation, using two photogrammetric 
coverages taken before and after the occurrence. The results obtained 
were described in a previous paper presented to ISPRS Symposium in Rio 
de Janeiro. Further developments of this study regarded the volumes com- 
putation of the slide masses, shifts and other fields concerning the mo- 
tion (ground deformation parameters) applying digital modelling tech- 
niques to height-variations of natural points on the terrain. 
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