ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

took place: various phases are characterized by the deposition
of transgressive marine sediments unconformably over
deposits of the Plio-Pleistocene cycle, in particular over
the «Argille subappennine» Formation.
The aim of this study has been to reconstruct the terracing
phase using both the buried abrasion platforms present at
the top of the bradanic deposits and superficial morphologies.
For this purpose the stratigraphies of some thousands
of wells drilled by Boards and Companies specialized in
water drillings have been analysed and in many cases
perforations of calibration have been realized. The results
of this regional preliminary study show that the Tavoliere
is divided into three different zones.
The Southern zone, between the Ofanto River and Cervaro
Stream, corresponds to a plane delimited by two important
tectonic lineations. This surface slopes down softly
towards the Adriatic sea, and shows evidence of the phases
of the sea mesopleistocenic-holocenic terraces. In the whole
it is possible to recognize eight marine terraced surfaces
put between 350 and 5 meters. Differently, a succession of
nine buried flat surfaces was recognized on the top of the
Plio-Pleistocenic Cycle, starting from 260 m a.s.l. to-40 m
b.s.l.. These surfaces delimited by evident slope can be interpretated
as abrasion platforms. Stratigraphical analyses
suggest that on these platforms there are marine deposits:
the deposits located at a higher level are formed by a single
sedimentary cycle, instead of the lower ones which are
composed of two or three sedimentary cycles, superimposed
upon the other.
The Central zone is perfectly contained between the Dauno
Subapennine and the Gargano Promontory. From the
morphological point of view the central sector is characterized
by two districts. The former is western, situated near
the mountains of the Subapennine, between 500 and 100
meters, the latter is eastern, and it is between 100 meters
and the present coastal plain. The characteristic of the zone
is given by the streams that join the Candelaro Stream.
These have deeply cut the highest area of the central Tavoliere,
and consequently they have isolated and divided the
marine terraces into flat ridges boarded with a series of fluvial
terraces. This situation made difficult the recognition
and the correlation of the marine phase terraced.
In spite of that, sixteen fragmentary buried flat surfaces
were recognized cut into the «Argille subappennine» Formation,
starting from 430 m a.s.l.. Above the first seven
platforms there are no evidences of marine sediments, these
have been recognized owing to the fauna starting from
the eighth platform. The deposits of the eastern sector are
formed by various superimposed sedimentary cycle up to
four.
The Northern zone is divided from the central one by the
Torre Mileto-Diga di Occhito Fault. This sector is characterized
by a young hydrographic grid, still in a phase of
evident regressive cut, which does not flow into the
Manfredonia Gulf but into the Adriatic Sea, west of the
Gargano Promontory. Besides, in recent times, the marine
streams have ridistribuited the sediments brought by the
Fortore River eastwards, forming the long coastal bar and
the consequent Lake of Lesina. Traces of the quaternary
sea level fluctuations are present only near the coast, where
the sediments reach the highest thickness in theTavoliere,
equal to 138 m.
SERGEY 1. BOLYSOV
The mapping of biogenic continental relief
Department of Geomorphology & Paleogeography, Faculty of Geography,
Moscow State University, 119899 Moscou, Russia
The biogenic relief is one of the least studied genetic complexes
of the continental relief yet. The principles of its
mapping are not worked out nearly. There are rare maps
of some biogenic forms (for example: organic coasts, individual
relic reefs, some bog complexes) or of local areas
with the high density of bioforms of relief. But usually biogenic
relief is reflected in general geomorphological maps
as one of many different genetic complexes on the occasions
of its dominating importance (as bog complexes) or
presence of large biogenic forms (as relic reefs). We adduce
proposed principles of mapping of biogenic relief in different
scales in this article as a result of drawing the maps
of the world continental biogenic relief and of the relief of
some key parcels in the Center of the Russian plain.
The maps of biogenic relief are the typical example of typological
geomorphological maps. Legend of my map of
biogenic relief (scale 1:70,000,000) reflects the zonality of
biogenic relief formation. The biogenic relief has bright
outline of geographical zonality more than some other genetic
complex. So the image of geographical zones of the
world (the adapted version of the Riabchikov's & alii map,
1988, was used) serves as the coloured base of our map.
The main biogenic complexes and the versions of indirect
biogenic influence upon the relief formation are reflected
in two columns in the table legend for the map. So the participation
of organisms in the relief formation is minimum
in arctic and antarctic cold deserts and is come to the biogenic
weathering in the main. The bog relief formation in
addition to bioweathering is developed in tundra broadly.
As these processes and zoogenic complexes formed by
beavers or a great number of zoogenic and phytogenic micro-
and nanoforms, root-denudation, tree gorges and
others play important role in the temporate belt forests.
The vegetation is of great importance in the deserts of tropical
and middle latitude as the factor of the structure of
difference of aeolian forms, also the zoogenic micro- and
nanoforms play important role. The termitariums are the
bright forms of the relief in savannes. The presence of organic
humus acids is the main factor of intensive development
of «tropical» karst in subequatorial and equatorial
climate. The «cattle-terraces», forms of root-denudation
and some others are typical for microrelief of mountains.
The second ground of symbols of the legend is the combination
of different areas of the most widespread forms or
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