Same 
(10) 
es for 
(11) 
(12) 
Since 
o the 
o the 
(13) 
(14) 
ding 
(15) 
(16) 
lance 
ntial 
er to 
pe as 
were 
ts, to 
Were 
rable 
the 
> 
) and 
1e (4 
  
141 
  
  
  
  
  
Fig. 1 - Aerial photogrammetric covering "before" and "after" the landslide. 
This means to consider, in the aerotriangulation adjustment, as "separated" the identical points "in landslide", whose displacements 
were to be known, and as "coincident" the identical points "out of landslide", which were supposed to be fixed. The reason of such 
a procedure is the impossibility of determining during the ground settling, by topographic operations, control points "contemporary 
to the flight". Note that, for the knowledge of the movements, the relative position between the two blocks is more important than 
their absolute position. For the higher strip only, the horizontal control points on ground were 12 and the vertical ones 69. Other 24 
height ground control points were taken from the shore-line, tide effect being corrected. Many tie points were made as pricked 
points, the others were mainly selected on buildings. 
By means of the collocation method, a digital model allowing to study in detail the surface deformation, was constructed on the set 
of the displacements values. In such a way one gained the knowledge, on a regular and dense grid, of both plano-altimetric and 
only altimetric movements; the former starting from the displacement determination on well identifiable points, the latter deriving 
from singling out the altitude changes (in the same planimetric positions). Figure 2 shows the altimetric deformation of the 
landslide body. 
In this way it was possible to point out the landslide boundary, to compute the earth settlements, to evaluate the volumes involved, 
to analyze the shape and the pattern of the fissures and the cracks, to observe building tilts and rotations. Figure 3 shows the 
characteristic lines of the landslide body. 
ANCONA '82 LANDSLIDE 
  
9800 
shore line 
  
     
2e DoE line 
- 
NORTH COOROINATE (a) 
1 
  
  
  
5800 — 
8000 — 
s200— 
8400 
8600 
o 0 
EAST COORDINATE (a) 
  
Fig. 2.- The altimetric deformation of the landslide body. Fig. 3 - Characteristic lines of the landslide body. 
The results of these evaluations confirmed and completed the information acquired by the direct survey executed by geologists, 
individuated the most critical areas to be verified later by control levelling campaigns, evidenced a lack of masses that, combined 
with some geophysical and geomorphological observations, permitted to draw a likely 3D model of the landslide falling in. 
5. LEVELLING CONTROL NETWORK, KINEMATIC ADJUSTMENT AND SPATIAL ANALYSIS 
( Barbarella, et al., 1990, Colombo, et al., 1986b, Crespi, et al., 1990 ). 
The settlement of the terrain went quickly decreasing after the landslide occurrence, but its extinguishment effects remained for a 
long time. Therefore, high precision spirit levelling campaigns have been repeated in order to evaluate the amount of the vertical 
movements. Their high frequency (about 2 months) and their long lasting (15+20 days) suggested to process the measurements by 
computing a kinematic adjustment. Figure 4 shows the graph of the levelling network. Note that the campaigns have not always the 
same pattern and length, because the results obtained modified the expectation of the subsequent one, leading to some changes and 
improvements of the network. : 
IAPRS, Vol. 30, Part 5W1, ISPRS Intercommission Workshop “From Pixels to Sequences’, Zurich, March 22-24 1995