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Geographica Timisiensis, vol. XXIV, nr. 2, 2015 (pp.5 – 11)●
QUATERNARY NEOTECTONICS IN ROMANIA AND
ITS CONSEQUENCES ON MORPHOLOGIC
LANDSCAPES
Mihai IELENICZ, PhD
Bucharest University, Romania
Abstract: At the end of Pliocene and in the Quaternary the alpine tectonic movements manifested
through Valachian and Pasadene phasis defining the present morphostructural system. They generated
the block raising of the Carpathian chain with regional differences however in intensity, sequentially
triggering the elevation of border regions (forming in this way plain, hill and plateau units),
favorizing local differences in the display of the relief forms, of types of morphologic landscapes,
producing subsidence areas, the fill in with Carpathian sediments of Getic and Panonian lakes and
individualizing several genetic types of plains etc. The system of morphologic changes had two
distinct phases, in Pleistocene and Holocene, displaying actually significant regional and local
examples.
Key words: neotectonics, geodynamics, morphotectonics, paleogeography.
INTRODUCTION
Tectonic movements in the late Pliocene and Pleistocene (Valachian and Pasadene
phasis) marked the end of a long geodynamic activity that began from Mesosoic and led to
the creation of the Carpathian orogene edifice. In structural terms they produced within
Carpathians a system of well organized sheets oriented towards East and South on the
directions of main tectonic movements that occured at the microplates contact. In
Quaternary the folding energy of the orogen became weaker and affected limited areas
within Subcarpathians (especially at the curvature region). Alternatively all the accumulated
tectonic energy manifested itself in epirogenetic movements, different as sense and intensity
from one structural unit to another, which were felt more intensely along the major crustal
fractures. There are numerous consequences of their occurence in the present relief. In order
to evidentiate them both the general paleogeographic situation at the begginning of
Quaternary and of the present relief as a result of a 1.5 – 2 million years of evolution must
be mentioned.
6●Quaternary neotectonics in Romania and its consequences on morphologic landscapes
1.
THE PLEISTOCENE GEODYNAMIC EVOLUTION AND ITS
REFLECTION IN RELIEF
At the beginning of Paleogeographic Quaternary there were two great basins of
lacustrine sedimentation (Pontian in the South and Panonian in West). Between them there
was a large region of land (mountains with an average altitude under 1600 m which were
surrounding a Transylvanian plain or low plateau on which the valley network was in a
process of generalization). In the East, in Moldavia there were plain units (low plateaus) on
which Siret, Prut and the main carpathian rivers were advancing towards South. In South
and West there were plain strips which penetrated within the mountain area along the
tectonic corridors sedimented in mio-pliocene (Timiş, Cerna, on Criş Rivers, Someş etc.).
Dobrogea was a peninsula, a continuation of the East-Balcanik region. From these land
units the (still forming) hydrographic network was bringing bed materials (sand, clays,
gravels), deposed under the form of immense cones within the marshy lakes or plains
(Panonian and Getic).
The result of tectonic impulses generated by the evolution of great tectonic plates
materialized in several directions:
the gradual block raising of Carpathian chain, various in intensity for its
different sectors;
the involvment in raising of Carpathians border regions which became
plateaus and plains;
evolving local subsidences within the area of plain units but also within many
tectonic intramountaineous depressions (Ciuc, Gheorgheni, Braşov, Haţeg etc.) (fig. 1);
in Dobrogea raisings (NW, SW) or slight lowerings (SE) with regional
character.
The consequences of their occurence on Pleistocene relief were different. In general
there were registered:
the present major orographic system displaying the relief in altitudinal steps
both at the exterior and at the interior of the Carpathian chain;
the appearance of a vast piedmontan plain at the begginning of Quaternary at
the exterior of the Carpathian chain (especially next to Southern Romanian Carpathians and
in part next to Wester Romanian Carpathians). Through up-raisal, in the second part of
Pleistocene differential fragmented piedmontan plateaus resulted. Within the sectors where
the subsidence was active (at the exterior of Bend Carpathians) psefitic and psamitic
overlapping sheets developed but without generating piedmont plains;
lakes’ replacement, which had been gradually filled in by sediments, with
marshy plain units;
the making of the hill and subcarpathian depression system through raisings,
different as intensity and even as direction from one sector to another. Significant up-raisals
occured in the Bend Subcarpathians where on different normal or faulted anticline or
monocline alignaments the Romanian – low Pleistocene deposits have been raised with
more hundreds of meters becoming summits and crests (locally reaching 850 – 1000 m
Mihai IELENICZ ● 7
altitude); they dominated depression areas (less involved in the raising movement) which
were given a sinclinal character. In Southern Subcarpathians (west from Olt) and in
Moldavian Subcarpathians one or two hill alignaments resulted on up-raising anticlins
which closed large areas with a character of sinclinal depressions (depression corridors) or
even a combination of the two and hills on salt deposits (Ocnele Mari);
the rising of Carpathians with an important intensity was made within two
distinct phases.
The first phasis was connected to the movements at the end of Pliocene and the first
part of Pleistocene and had two important consequences:

A significant deepening of rivers in the Carpathians led to the passage from
large valley profiles (marked by extended Pliocene erosion levels) to narrow valley sectors
(erosion shoulders, less extended terraces and incised meanders e.g.: on Jiu and Olt rivers);

at the exterior of Carpathians tectonic movements slightly raised the
bordering plateaus with lower intensity along the deep faults. Consequently large
interfluvial plateaus outstood. They were separated by low corridors (as a tectonic reflex) in
which great hydrographic courses were settled (Siret, Bistriţa, Trotuş, Buzău, transylvanian
Olt, Mureş, Someş, Timiş, Cerna etc.). On various sectors they followed lower alignments
centered on profound faults or fractures (Someş downstream to Dej, Mureş, Târnave rivers,
Siret, etc.) or on filled in grabens (Timiş, Cerna, Criş rivers, etc.).
The second phasis of significant neotectonic movements occured at the end of
Pleistocene and had numerous consequences for relief forms (fig. 1).

the intensified up-raisal of several Carpathian units that reached altitudes
higher than the limit of permanent snows (Riss and Würm). Consequently in the catchment
basins of the valleys located above 1800 m glaciers as well as periglacial processes
developed. There were created (circus, valleys, tresholds, moraines etc.) numerous
crossroads crests, peaks and significant amounts of gravel which altimetrically develops
above 1000 m;

in the mountain areas as well as in the neighbouring areas, the modelling,
mainly fluvial, on the background of succesive up-lifts, facilitated a significant deepening
(frequently 40 – 50 m) of main rivers; 3-5 levels of terraces resulted (locally some more 1 –
2 steps added through doubling on neotectonic axes positive-active), depression basins
found on litostructural contacts, thick alluvial sheets (würmian) which fill in deep valley
bottoms (Bistriţa, Trotuş, Buzău etc.); longitudinal profiles on secondary rivers with
accentuated slopes often lifted above the flood plains of the main valleys, alluvial cones in
confluence areas on the frame of large intramontaneous depressions or at the border of
mountains) which have sometimes an aspect of glacis or piedmonts (Maramureş, Dorna,
Ciuc, Gheorghieni, Braşov, Făgăraş, Haţeg, the ones at Criş rivers exits towards West Plain
etc.);

the differentiation in intensity of the up-raisal on structural units led to
deformations in the display of some erosion areas and levels (their position at various
altitudes from North to South in the Bend Subcarpathians; from West to East in Southern
Carpathians; Banat Mountains raported to the western branch of Southern Carpathians etc.)
in the display of terraces along main valleys (especially in the Subcarpathians where they
grow in altitude on the raising anticlines and decrease till their disappearance within the
8●Quaternary neotectonics in Romania and its consequences on morphologic landscapes
subsident sectors). One should also mention the development of hydrographic convergent or
divergent areas within extended depressions at the border of Carpathians, asimetries in
terrace development (at Argeş, low Siret, low Bârlad, Bistra, Jiu) etc.
Regionally, for Pleistocene, through the way in which tectonic movements reflected
themselves in the relief characteristics, several geodynamic units might be separated:
A great geotectonic unit in which positive movements produced comprise the
Carpathians, the Subcarpathians, the plateaus of Moldavia, Transylvania, Dobrogea (in part)
and a part of piedmont plains (Getic and West) were raised with different intensity (more
important for Carpathians and for some sectors in Subcarpathians, average and week for the
rest). Beside them local faults and disturbances were also present. There were definitivated:
the contour and altitudes of the main morfostructural units, the development of 2 – 8
terraces major valleys network, the formation of glacial complexes, the main deformations
in the development of carpathian and subcarpathian erosion areas and levels etc. The
amplitude of up-raisals evaluated on the basis of altitudinal position of RomanianPleistocene deposits (from 200 m at almost 950 m), of erosion levels and terraces on the
corridors of main valleys and through them the amplitude of segments within transversal
profiles of valleys detached in Quaternary indicate different values in mountains (between
400 – 600m), regionally different within the hill and plateau areas (100 – 300m) (locally
these territories may reach even 900 m – for instance in Subcarpathians) and under 50 m in
some high plains.
Small geotectonic units which suffer downward movements may be the plains
(Timiş, Criş rivers, Someş, from Argeş to Siret etc.) or the depressions (Gheorgheni, Ciuc,
Braşov etc.) with subsident character which have specific alluvial accumulations
(overlapped sheets) and landscapes dominated by dry riverbeds, lakes and marshy areas.
The intensity of geomorphologic processes depends on the vertical movement of foundation
blocks (West Plain) or on the subduction of those from the Carpathians curvature. On this
area the movements are generated by the microplates movement as well as by the pressure
exerted on the foundation blocks by the rich sediment accumulations brought by the rivers
with springs in Carpathian or hill regions.
2.
THE GEODYNAMIC EVOLUTION IN HOLOCEN – PRESENT DAY
PERIOD AND ITS REFLECTION IN RELIEF
This evolution is represented by the manifestations generated by the movements from Upper
Pleistocene which represent local changes as intensity and direction. The short period (of
only 9000 – 10000 years) do not lead to an important reflection in relief of neotectonic
movements especially through the creation of forms with great dimensions.
First of all the general up-risal tendency for the greatest part of relief units imposed
itself and then the constriction of areas where the subsidence remains active (Ciocârdel et
al., Cornea et al., Popescu et al., Zugrăvescu et al. etc

The positive movements know different dimensions from one unit to another.
The general tendency to push westward the assembly of carpathian units which come into
contact with the rigid units of platform, differently fracturated and lowered, reflects itself in
Mihai IELENICZ ● 9
more accentuated up-raisals in the sectors found north from Bistriţa (direct contact between
the Carpathian flysch and the fundament of Moldavian plate on which the previous one
overflows) and between Trotuş and Dâmboviţa (area in which the flysch sheets subduce
units from Black Sea and Valachian microplates). The geophysic and geodesic studies
(from the last decades) indicate values of 3-4 mm/year and locally over 5 mm/year. The uplift affects on the one hand the mountain units (more intensely in the border sectors) but also
their immediately bordering units (Sucevei Plateau, Bend Subcarpathians). For these units 2
– 4 steps have been cut within the thick alluvial sheets of the flood plains while the majority
of main tributaries built 2 – 3 generations of fingered alluvial fans. In the Bend Carpathians
and Subcarpathians their up-raisal, on the general subduction background of south-east and
south platform units, was accompanied by an active seismicity and an intense dynamics of
slope processes within the conditions of slopes that remained unbalanced. The general
positive movements locally produced in some depressions in the Eastern Carpathians (Ciuc,
Gheorgheni) even the change of the subsident movement into a very slow raisal (0-1
mm/year) more important on their eastern part or on southern area (Braşov). In this area
rivers developed alluvial fans on the border regions and in the interior a landscape of
smooth alluvial plains with humidity excess, low river banks, dry riverbeds and marshy
vegetation. Westward to Olt in the Southern Carpathians, Western Carpathians and
Subcarpathians the up-lift intensity is much more lower (around 1mm/year and only locally
2mm/year) while the slight subsidence maintains itself in some tectonic depressions (Haţeg,
Călan, Petroşani, Târgu Jiu – here there are less extended plains on which rivers coming
from bordering mountain units develop alluvial fans but also hydrographic convergences
inherited from pleistocene).
In the hill and plateau units there are various situations. First of all within
Subcarpathians, West Hills, Getic Plateau, and Transylvanian Plateau one should notice a
general up-lift movement (between 0 and 1 mm/year) as a result of their involvement in this
process by the Carpathians movement. The particular situations are introduced by some
more accentuated movements (around 2 mm/year) in the mountain immediate neighboring
area (Subcarpathians) or on aligmnments of diapir strata (Transylvania, locally in
Subcarpathians, an active morphodynamic on the not yet balanced slopes). Secondly there
are slight downward movements (0 - -1mm/year) especially along depressions or valley
corridors oriented tectonically on profound, old but still active fractures or which
correspond to areas of neotectonic compensation (at the exterior of some up-raising units).
They are met along Siret, Mureş (from Ocna Mureş to Simeria), along Olt in Transylvania,
Timiş (downward to Caransebeş) etc. On these sectors there are large and smooth flood
plains and intense alluvial accumulations on which there are frequent unplaites. On Mureş,
as the geophysic and geodesic studies indicate, the local strengthening of the lowering
movement in Alba Iulia corridor will be reflected later on (if it will persist) in the
morphologic landscape. However it is anticipated by the extended flood plains and the
hydrographic concentrations (gathering places).
Particular situations are met in Dobrogea Plateau and in the central part of Romanian
Plain. In the first unit after the general up-lift, with different intensity in Pleistocene, the
10●Quaternary neotectonics in Romania and its consequences on morphologic landscapes
plain area was affected in Holocene by two tendencies. First one should mention an upraisal with 1-2 mm/year in south-west (the neotectonic affirming of Silistra anteclysis) and a
more accentuated lowering (1-2 mm/year) in south-east (south from Constanţa) and which
tends to comprise gradually the center and the north of the plateau. The general lability of
Dobrogea subunits is favorized by the existence of some profound fractures (Sf. Gheorghe,
Peceneaga-Camena, Capidava-Ovidiu, Danube) which are reactivated through tectonic
impulses resulted at the contact between the orogen at curvature area (advancing towards
SE) and the dobrogean blocks (under the previous one). The change of the plateau
movement from upward to downward (Zugrăvescu et al. indicate values of -2, -3 mm/year)
was recently made as particularly the relief and generally the landscape miss obvious
supporting elements. Maybe only the presence of Danube pools, of loess banks, of ex
inselbergs ‚drawn’ by the river’s sands, the rich alluviation which generated deposits over
10 m thickness (considered by Banu as a consequence of the Holocene remuu caused by the
raising of the sealevel at + 5m etc.) seem to indicate the beggining of this process reflection
in landscape. Its materialization in relief is obvious only on the littoral sector strip where the
cliff suffers an active withdraw (some low sectors are already under water – at Mangalia –
„the Roman cemetery”) and to a certain extent within the large corridor of
Cernavodă-Constanţa. Human activities along the littoral (consolidations, sea-walls raisals,
various accumulations, cannals, etc.) limit the consequences of normal development for
natural processes. In Romanian Plain (center and south) from Olt and till the middle part of
Bărăgan geophysicians put in evidence up-lifts only in two sectors (values over 2 mm/year),
probably as reflection of Silistra anteclysis and Optaşi-Balş convexity influence. Certainly
this movement is older than the Holocene, proved by the 1-3 terraces detached on the main
rivers which cross the region and even the shape itself of the Danube corridor.

The negative movements are limited to smaller areas than in Pleistocene, but
are maintained and sometimes have a great intensity (over 2 mm/year) in sectors with active
profound faults which separate blocks in the basement.
In West Plain (Banato – Someşeană) there are significant sectors on Someş, Criş
rivers, Timiş-Bega where the East-West fractures cross the North-South ones generating
situations of tectonic instability. Although the Carpathian rivers bring an important volume
of alluvial materials their profile is not balanced because of the subsidence which leads to
the persistency of the marshy process for fields in general (the ground water sheet is close to
the surface), to frequent flash floods (in the absence of high banks), to changes in river bed
position (Someş, Crasna, Timiş etc.), to the passage of flood plain level into the plain level
and even into the first terrace level present in the valley corridors within West Hills, to the
maintenance of hydrographic convergences.Here in the normal (natural) landscape estate
changes have been produced by the numerous human works destinated for the agricultural
use of the plain. Among these one should mention: a dense network of discharge pipes that
started to be built since the end of 18th century, then 2-10 m high walls for flood protection
(the most significant were settled after 1970), the lake creation for fish breeding or for
irrigations etc.. Consequently important areas have lost their physionomy specific for a
subsidence plain. However its characteristics (the dominance of marshy areas) come out
Mihai IELENICZ ● 11
easily during the periods with heavy lasting rains. In the Romanian Plain the subsidence is
located in several areas, the most extended being in North East (the plains of Sărata, Buzău,
Siret, Galaţi) which coincide with crossroads sectors of pericarpathian fault with fractures
that come from Dobrogea and the eastern part of Moesic Platform. In this way these areas
overlap the region which reflects most obviously the curvature subduction process. The
Carpathian rivers with an extremely active erosional potential generated accummulations of
hundreds of meters thickness. On the border of hill regions they generated fingered alluvial
fans that became an enormous piedmont glacis which hides the contact with the plain area.
East from Mărăşeşti-Focşani-Balta Albă the very active subsidence prevented the extension
of the glacis. Here the marshy fields dominated (at present with many drainage cannals)
with salty and marsh soil, and there are frequent dry river beds, oxbow lakes or fluviatile
lakes. Similar situations also exist in the plains of Titu-Găeşti and between Buzău and
Călmăţui.
REFERENCES
Airinei Șt., 1979, Teritoriul României și tectonica plăcilor, Editura Științifică și Enciclopedică,
București
Ciocârdel R., Popescu M., 1965, Tendences actuelles de mouvements de l’ecorce terrestre en
Roumanie, R.R.G.G.G., Geogr., 49, 12
Ciocârdel R., 1966, Esset de syntese des donnes actuelles concernant les mouvements verticalex
recents de l’ecorce terrestre en Roumanie, R.R.G.G.G., Geophisique, 14, nr.8
Cornea A.I., Drăgdescu I., Popescu M., 1979, Morphography of crustal recent vertical crustal
mouvements of Romanian territory, S.G.G.G., Geofizica, 17
Ielenicz M., 1972, Considerații privind mișcările tectonice din cuaternar și reflectarea lor în relief,
Buletinul Științific Baia Mare, vol. IV
Liteanu E., Gheneac C., 1966, Cuaternarul din România