662 
a classification elaborated. The classification 
Hows a systematic study reordering the existent 
terminology, moreover the conceptual content of each 
term was reformulated according to its dynamic. (Po- 
polizio 1973a) 
Linear symbols and letters were used for the carto 
graphy. It could be pointed out that the transfluence 
from one basin to the other is particularly indicated, 
since it is a frequent phenomena in Argentine plains 
and very important from the applied geomorphology 
point of view. This work made the photointerpreter 
task and its corresponding cartography easier. 
At the same time and considering that different 
types of surface run-off frequently tend to reach an 
ordered spatial association, though not so well defin- 
ned. as in., the major..amplitude relief,surface runoff 
network must be specially taken into account (Popoli- 
zio 1973b) 
Fourteen elemental network models were defined and 
also characterized^into .integrated or desintegráted,- 
whether they are divergent or convergent. After these 
models we can pass to more complex patterns. The last 
ones are the most frequent all the more as larger the 
analyzed network is and climatic, edaphic, vegetation- 
al, geological,or geomorphological variance of the a 
area where it is developed. The advantage of consi 
dering elementary models, consists in that any varian 
ce from one towards the other, indicates certain con 
ditioning by any of the above mentioned factors, with 
out leaving aside such a widespread influence as the 
anthropic. Evidently these model changes can require 
an adequate observation scale and so it is not advi 
sable to manage only one. 
Using a matrix in which diagonal appears pure ele 
ments, possible models have been indicated and 
supposed elements combinations in twoes, the composed 
network. 
By means of an adequate descriptive formula the 
type of network is defined, which allows also to 
indicate the existence of two models interjoined in 
a sole net/ a paleonet presence and the sequential 
trend towards a determined net. In this way dynamic 
aspects can be established to the use of formulas 
that have been incorporated to the legend. (Popolizio 
1973b). 
On these fundamental elements, connect to the co 
rrect interpretation of plains geomorphological cha 
racteristics, the thematic cartography elaboration 
was carried on. 
For a geomorphological map at semidetailed level, 
scale 1:50.000 (La Escondida) an areal symbology was 
designed for corresponding mapping units. They belong 
to forms of structural origin, forms of fluvial ori 
gin, paleoforms of eolic origin and corresponding 
symbology to morphometry, transport and urban infra 
estructuras, also. 
It should be pointed out that lithology is not 
included in these maps, appart from corresponding 
printing difficulties. From one hand the relative 
homogeneity of quaternary sediments must be consider 
ed and moreover, if its variation has an important 
geomorphologic value, it is indicated on legend. 
Due to originated importance or vegetation influence 
to define geomorphic units, the same as from the 
applied point of view, phytogeographic chart at 
equal scale is elaborated at a physognomy level. 
Corresponding limits are determined and accompaning 
letters are shown and defined in the legend. Geomor 
phologic maps at scale 1:250.000 were also elaborated 
where structural elements are indicated (lineaments) 
and the units of second order limit, as well as the 
corresponding subunits of third and fourth order. 
They were accompanied by numerical symbols related 
to decimal classification system, which were express 
ed in the legend by unit definition and its corres 
ponding vegetal association- 
On the same areas and at equal scale synthesis maps 
about surface runoff dynamic were elaborated. There, 
basins, river courses and its features, transfluence, 
headwater retreat, etc. were defined. 
In every basin identified by a letter the surface 
run-off system is'describéd'iñ the' legend. 
From the applied geomorphology’point'of view and the 
water resources management, this thematic map is 
essential and very useful. 
On the pampean plain sector which corresponds to 
the south of Santa Fe Province and its adjacent zone 
belonging Paraná river valley and its delta, a 
geomorphological mapping at small scale 1:1.000.000 
was performed on the base of Landsat imagery. 
On these areas members of the Instituto de Fisio 
grafía y Geología have carried on previous studies 
along two decades and more, using aerophotographies 
and topographic maps at different scales and includ 
ing field works. 
Structural lineaments are indicated in cartography 
to which the limits of second order units are asso 
ciated and third order subunit are considered as forms 
of structural origin, hydrographic networks of major 
hierarchy and lakes were included using conventional 
symbol. On the base of detectable elements on Landsat 
imagery; fourth order subunits were detected and 
indicated separately using conventional symbology also 
(Canoba 1982) 
The geomorphological mapping at 1: 1.000.000 scale 
of one adjacent sector of Parana river delta was a 
very valuable experience where the ITC system for 
geomorphological surveys were used. Geomorphological 
units and subunits determinations could be used due 
to the fact that geoforms can be perceived in the 
small scales images thus allowing its interpretation. 
This occurs for the reason that Parana river Delta 
has an unusual dimension compared to those correspond 
ing to other deltas in the world. 
It should be pointed out that previous studies of 
some of these areas with terrain classification pur 
pose on the bases of their geomorphological characte 
ristics were performed at 1:100.000 scale. Geomorpho 
logical surveys at 1:20.000 scale was carried on in 
key sectors. (Pasotti et al 1976). 
Aerophotography and cartography at different scales 
utilization and particularly Landsat images from 
different periods of the hydrologic year, allows the 
improvement of some aspects of fluvial dynamics inter 
pretation. 
CONCLUSIONS 
As conclusion of our experience about geomorphologi 
cal studies on Argentine plains, using remote sen- 
single realize that frequently the same method co 
rresponding to the zonal level is used (been the one 
where the most of the experiences were carried on). 
Nevertheless it is considered that it should not 
be so and is very particularly reiterated for plains 
studies. 
Each survey level implies a corresponding perception 
level and a particular methodological adjustment 
(Table 1). 
We can also define three types of photointerpreta 
tion (image interpretation according to the above 
mentioned levels: (the generalist, the integrator 
and the especialist). Even when they are complemen 
tary, each of them has a great importance either from 
the interpretation point of view or from applied 
geomorphology. The regional level surveys are used 
for the sake of taking decisions, those of zonal 
levels are for planning and those of local level are 
for specific projects or works. That is why synthesis 
stated on Table 1 is presented as a contribution, 
being supported by our experiences and the expressed 
concepts. So we can consider it as a useful base for 
work performance as much as for photointerpreters 
formation. 
REFERENCES 
Canoba, C. 1982. Geomorphological mapping using Land 
sat imagery: a case study in Argentina. ITC Jour. 
1982-3, p.324-329. Enschede. 
Canoba, C. & Popolizio, E. 1968. Estudio aerofotográ- 
fico de paleopotamología en un sector ribereño del 
rlo Paraná-Chaco. Inst.Fis.y Geol. Notas №2 UNR 
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