The Annals of Valahia University of Târgovişte, Geographical Series, Tome 8 / 2008 ______

RELIEF UNITS AND PREVALENT SOILS IN DÂMBOVIŢA COUNTY

ŞTEFAN ISPAS*

Summary: Dâmboviţa County is characterized by a very varied relief, which includes three big different units: the mountain unit, the hill unit and the plain unit. The mountain unit (9%) is represented by Bucegi Mountains and Leaota Mountains. The hill unit, which is much more extended (30%), includes The Ialomiţei Sub-Carpathians and Cândeşti Piedmont. The Ialomiţei Sub-Carpathians represent a hilly subunit, which was formed at the end of the alpine orogenesis, by the folding of the sedimentary deposits accumulated in the Carpathian deep syncline; Cândeşti Piedmont represent a tableland subunit, with a monocline structure, whose genesis has begun much earlier before The Sub-Carpathians. The plain unit, which is the most extended (61%), includes piedmont plains (such as Târgoviştei Plain, Cricovului Plain, Ploieştilor Plain, Piteştilor Plain, Găvanu-Burdea Plain), flaggy plains (Vlăsiei Plain) and subsidence plains (Titu Plain and Ibrianu Plain).

Key words: mountain, hill, piedmont, plain, dejection cone, subsidence, flaggy relief, soil.

Rezumat: Judeţul Dâmboviţa se caracterizează printr-un relief foarte variat, în cadrul căruia au fost separate trei mari unităţi: de munte, colinară şi de câmpie. Unitatea montană (9 %) este reprezentată de Munţii Bucegi şi Munţii Leaota. Unitatea colinară, mult mai extisă (39 %), cuprinde Subcarpaţii Ialomiţei şi Piemontul Cândeşti. În timp ce Subcarpaţii Ialomiţei reprezintă o subunitate deluroasă, care s-a format la sfârşitul orogenezei alpine, prin cutarea depzitelor sedimentare acumulate în avanfosa carpatică, Piemontul Cândeşti reprezintă o subunitate de podiş, cu structură monoclinală, a cărei geneză a început cu mult înaintea Subcarpaţilor. Unitatea de câmpie, cea mai extinsă (61 %), are în componenţa sa câmpii piemontane (Câmpia Târgoviştei, Câmpia Cricovului, Câmpia Ploieştilor, Câmpia Piteştilor şi Câmpia Găvanu – Burdea), câmpii tabulare (Câmpia Vlăsiei) şi câmpii de subsidenţă (Câmpia Titu şi Câmpia Ibrianu)

Dâmboviţa County is characterized by a very varied relief which lowers from north to south, like a flight of steps, from over 2500 m. in the north to approximately 100 m. in the south. We can also notice the same big variety in the lithological structure; this fact, associated with climate and vegetation, has determined the vertical soil zonality. As a result, we can notice inside Dâmboviţa County three big different relief units: the mountain unit (9%), the hill unit (30%) and the plain unit (61%); each of the above mentioned units includes several subunits.

I. THE MOUNTAIN UNIT

The mountain unit lies in the Northern side of Dâmboviţa County and includes Bucegi Mountains and Leaota Mountains, which are very different if we take into account their geological structure and their relief appearance. Bucegi Mountains have the form of an amphitheatre with southern opening, delimited by almost vertical abrupts compared with the coterminous areas; for example, the abrupt towards The Valley of Prahova is characteristic. These mountains are mainly made up of conglomerates and sandstones and less of limestone. From the structural point of view, they correspond to a suspended syncline; the Ialomiţa river installed on the axle of this suspended syncline. The maximum height is 2505 m., reached by Omu Peak. There are several glacial valleys around this peak (The Valley of Ialomiţa, Mălăieşti Valley, Gaura Valley). The superior side of these mountains has the form of an extended structural surface, bearing the

* Valahia University of Targoviste

65 The Annals of Valahia University of Târgovişte, Geographical Series, Tome 8 / 2008 ______name of ,,the plateau of Bucegi”; strange relief forms, such as “Babele” and “Sfinxul”, were created within this plateau as a result of the differential erosion. The structural relief is also characteristic for Bucegi Mountains and it is more obvious of the flanks of the syncline. The carst relief is present along The Valley of Ialomiţa, where caves and gorges can be met, such as: The Cave of Ialomiţa River, Urşilor, Tătarului, Zănoagei, Scropoasei and Orzei Gorges. Leaota Mountains lie in the west side of Bucegi Mountains; these two mountains are separated by Brăteiului Valley, continued with the Valley of Ialomiţa until the locality bearing the name of . Leaota Mountains are made up of crystalline metamorphic schists and their maximum height is 2135 m., reached by Leaota Peak; the periglacial phenomena are intensely developed around this peak. It has recently been proved the existence of the glacial relief, too, within these mountains (Murătoreanu G., 2008). Generally, the relief has the form of some summits with rounded backs, whose morphology was influenced by the crystalline metamorphic schists, which are very resistant to erosion. Some little carst areas are encountered only in the north-western and south-eastern side, awarding picturesque aspects to the relief. Within the mountain unit, there are some hazy opinions concerning the compartment situated in the south of Bucegi Mountains, between Ialomicioara Valley and The Ialomiţei Sub-Carpathians. In “The Geography of ”, III-rd volume, this compartment is included in Bucegi Mountains (page 244 and page 247), although the southern limit of these mountains has previously been settled at Ialomicioarei Valley (Velcea Valeria, 1961). The above-mentioned area is included in Gârbovei Mountains, from which it has probably been separated as a result of the formation of the superior valley of the Prahova river, in “The Geography of the Romanian Carpathians and Sub- Carpathians” (Velcea Valeria, 1982), on the map of Bucegi mountain complex (page 111). Because of the specific features of its relief (Gurguiatu Peak is 1338 m. high), the above-mentioned compartment is different from Bucegi Mountains, as well as from The Sub-Carpathians; if it is included in Gârbovei Mountains, this means that The Valley of Prahova is no more such a categorical bound between The Eastern Carpathians and The Meridional Carpathians.

II. THE HILL UNIT (THE HILL AND TABELELAND UNIT)

It is represented by The Ialomiţei Sub-Carpathians and by Cândeşti Piedmont, which represent the central-northern side of the county. The Ialomiţei Sub-Carpathians lie in the east of the valley of the Dâmboviţa river, having very clear bounds both to the north, towards the mountain area, and to the south, toward the plain area. They were formed at the end of the alpine orogenesis, by the folding of the sedimentary layers accumulated in the Carpathian deep syncline. The Sub-Carpathian relief consists in hills, depressions and valley passages. The adaptation of the relief to the folded structure is obvious, because some hills correspond to the anticlines, and the valleys correspond to the synclines. But there are relief inversions, too. Depending on the genesis, petrographical structure and the special features of the relief, we can distinguish the internal Sub-Carpathians in the northern half and the external Sub-Carpathians in the southern half. The internal Sub-Carpathians are older and consist in cretaceous and paleocene flysch; they are represented by hills that have the form of some summits, being 600-800 m. high. In the northern side, at the contact with The Carpathians, there is an alignment of the contact depressions, having a tectonic and erosive nature (Mihăilescu V., 1966); , Runcu and Moroeni depressions are representative.

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Văleni Dâmboviţa Depression lies approximately on the same alignment, but in the west of the valley of the Dâmboviţa river; within Văleni Dâmboviţa Depression, the folded structure in the Sub-Carpathians interferes with the monocline structure of Cândeşti Piedmont, which causes the appearance of a sector having a very complex structure. To the south, at the bound between the internal Sub-Carpathians and the external Sub-Carpathians, there is a second range of depressions: Voineşti, on the Dâmboviţa river, , on the Ialomiţa river and Valea Lungă on the Cricovul Dulce river. We must notice the appearance of several isolated hills, known with the name of knolls. The external Sub-Carpathians are younger, consist in soft pliocene deposits, less resistant to erosion and are represented by hills having more reduced altitudes (400 – 600 m.) and more gentle slopes; that is why they are called table lands: Pietrei Table Land, Stânei Table Land, Pârliturii Table Land. We must notice the appearance of a new range of depressions, some of them being smaller, but very well individualized, such as Glodeni and Ocniţa depressions. To the west, Depression on the Cricovul Dulce river is much larger. Ocniţei Depression is a buttonhole resulted from the differential erosion within a diapire fold. The increased fragmentation of the relief and the alternation of the rocks (sandstones, clays, marls), which are specific elements for the entire Sub-Carpathian area, has encouraged the intense progress of erosion process and of landslides. As a matter of fact, the eroded soils and the colluvial soils are very spread, precisely because of the erosion process. Yet, the prevalent feature of the soil layer is given by the presence of cambisols; within cambisols, eutric soils are more frequent in the external Sub- Carpathians, and dystrict soils appear in the northern side, at the contact with the mountains. Luvisols are specific for the backs of the hills. Cândeşti Piedmont lies in the eastern side of Dâmboviţa County, having an elonged form on the north-south direction. It is older than The Ialomiţei Sub-Carpathians, consisting in carpathian sediments; within these sediments, we notice the thick deposits of gravels, known under the generic name of “Cândeşti gravels”. The formation of The Sub-Carpathians has separated the above-mentioned piedmont from The Carpathians and has contributed to the slight raising of the northern side of the piedmont, increasing even more the monocline structure of the layers. The general aspect is one of a piedmont tableland, fractionated into long summits, slightly inclined from north to south. In the northern side it reaches 680 m. high and in the southern side, at the contact with the river plain of the Argeş river, it descends until 220 m. high. The structural relief, generated by the monocline structure, is more obvious in the northern side, which is higher and more fractionated. From north to south, the entire piedmont is sectioned by the valley of the Potop river, which deepens much in the thick mantle of the sedimentary deposits. Landslides and soils affected by erosion processes occur on the slopes. The aspect of high plateaus which is specific to the interfluves, often with imperfect external drainage, has encouraged the formation of the following types of soils: luvisols, planosols and soils with still water; these soils are rich in clay and have a totally unfavorable air and water regime; that is why the agricultural cultures are very limited and the forests are prevalent.

III. THE PLAIN UNIT

It lies in the southern side of Dâmboviţa county and it is the most extended relief unit in the above-mentioned county. Taking into account the genetic, morphological and pedological aspects, the following classification of the plains can be made: piedmont plains, flaggy plains and subsidence plains.

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Fig. 1.1. The map of relief units and subunits in Dâmboviţa County

The piedmont plains represent a joint level between the hill area and the flaggy plains, having a general inclination from north-west to south-east. The contact with the hill area in the north is realized on the alignment of the localities: Dragomireşti (in the north of Târgovişte) – Gura Ocniţei – Moreni.

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These are the oldest subunits of the plain area, appearing as land since the beginning of the Quaternary. They were formed because of the deposition of sediments by the Argeş, Dâmboviţa, Ialomiţa and Cricovul Dulce rivers. As a result, the lithological substratum is dominated by the presence of the gravels and of the riverine sands, covered by a clayey layer (3-5 m.), which have represented the basis of the soil cover formation. The relief is represented by large interfluves, separated by deep valleys. In their prevalent side, the piedmont plains have altitudes between 200 – 300 m. high. The prevalent soils belong to the luvisols class. Târgoviştei Plain lies in the central side of the county and is the most extended from the piedmont plains; it has resulted from the unification of the dejection cones of the Dâmboviţa and Ialomiţa rivers. Within the above-mentioned plain, there are two different compartments: a western one represented by Picior de Munte Plain, and an eastern one represented by the interfluve included between the valleys of the Dâmboviţa and Ialomiţa rivers. Picior de Munte Plain lies between the valleys of the Cobia and Dâmboviţa rivers; it extends towards the south until the region of Fusea railway station, and its relief is represented by a succession of 3 terraces of the Dâmboviţa river. On the map of Romania’s relief units (Posea Gr., 1984), Picior de Munte Plain is included in Cândeşti Piedmont. We have to mention that, although it is situated in the continuation of Cândeşti Piedmont, this relief unit has enough specific features that permit its separation from Cândeşti Piedmont. We can mention here the following specific features: it is a newer relief unit, it has lower altitudes (180-200 m. high), terraces relief (similar with the one in Piteştilor Plain) and the agricultural lands are prevalent. Dâmboviţa – Ialomiţa interfluve lies on the direction north-west - south-east and its altitudes descend from 340-320 m. high in the north of Târgovişte to approximately 150-160 m. high on the alignment of Bolovani-Alunişu-Bilciureşti localities, that outlines the basis of the dejection cone; both the Dâmboviţa, and the Ialomiţa rivers have contributed to the formation of the above-mentioned dejection cone. In the south of Alunişu locality, the runoff slope is reduced very much and the stream of the Baranga river becomes very windy; it means that this is the passage point into another relief unit. This interfluve does not connect with any of the terraces of the Dâmboviţa river, nor with the surface of Cricovului Plain, having a personal evolution. Compared with Picior de Munte Plain, the relief of this interfluve is much more uniform, which has determined the very big extension of the agricultural lands. The only discontinuity in the relief is determined by the valley of the Ilfov river, which deepens with 15-20 m. considering the general level of the plain and has breadths up to 2 km. It is difficult to admit that such a big valley could be realized by such a little river, as the Ilfov. Concerning this aspect, George Vâlsan (1915) considered that “The separation (of the Dâmboviţa river) from the Ialomiţa river is considered to have occurred after the formation of the dejection cone from Târgovişte, which has allowed the river to lose its way either on the valley of the Ilfov river, or on the valley of the Colentina river, because of its flat form”. Cricovului Plain, also known with the name of “Măgurii-Knoll Spur” in the specialized literature (Vâlsan G., 1915) or “Măgurii-Knoll Plain” (Mihăilescu V., 1960), lies in the east of Târgovişte Plain, between the valleys of the Ialomiţa and Proviţa rivers, and it is continued by the valley of the Cricovul Dulce river. From Moreni, where its altitude reaches 320 m. high, it extends much to the south (for approximately 30 km.), reaching the north of Frasinu locality, where its altitude decreases until 160 m. high. It is very different compared with the environing regions because of its steeps, whose height is reduced from north to south (40 – 10 m. high) and because of the fact that

69 The Annals of Valahia University of Târgovişte, Geographical Series, Tome 8 / 2008 ______it is afforested in its biggest part. The soil cover is dominated by albic luvisols, planosols and soils with still water, which have physical and chemical properties that are totally unfavorable for the agricultural cultures. In Bucşani Knoll, considered a brachy-anticline, it reaches 346 m. high, which can be considered one of the highest altitudes in The Romanian Plain. The genesis of this plain is very disputed and it has aroused the experts’ special interest. Thus, it was considered a dejection cone (Vâlsan G., 1916), a terrace (Popp. N., 1938), a piedmont (Mihăilescu V., 1966), a high piedmont plain (Niculescu Gh., 1960), a piedmont fragment (Velcea V., 1982) or an old piedmont having an aspect of a dejection cone (Posea Gr., 1988). If it is only a fragment, it means it has had a much bigger extension; but if it is an old piedmont, it means it might be even older than The Sub-Carpathians, whose raising might have generated an intense riverine erosion, which has allowed the Cricov river section deeply this piedmont and the brachy-anticline from Bucşani might be the echo of the foldings of The Sub-Carpathians. Ploieştilor Plain represents the dejection cone of the Prahova river and it has a very reduced extension within the surface of Dâmboviţa county, in the east of the valley of the Proviţa river. It has a much more uniform relief (the altitudes reach constantly 200 – 240 m. high) than Cricovului Plain; in contrast with the latter, it is mostly covered with agricultural cultures, which are encouraged by the soils rich in calcium carbonate (mollic eutricambisols). Piteştilor Plain lies in the west of Dâmboviţa county and it represents the dejection cone of the Argeş river; after the land shaping of the above-mentioned dejection cone, a plain of fan terraces and a divergent hydrographical net have resulted. The inferior terrace in the right of the Argeş river disappears in the point where Stavropolia locality is placed, which can be considered the southern limit of this plain. To the west, it is very hard to establish the southern limit. Considering the prevailing of the luvisols to the north and of the preluvisols to the south, the southern limit could be mapped out on the alignment of Stavropolia – Răscăeţi – Vultureanca localities. It has altitudes which decrease from 220 m. high in the north to 180 m. high in the south. Generally speaking, it is noticed that the southern limit of Piteştilor Plain is connected with the southern limit of the inferior terrace of the Dâmboviţa river, which disappears in the point where Fusea railway station is situated and with the southern limit of the dejection cone between the Dâmboviţa and Ialomiţa rivers. Găvanu-Burdea Plain lies in the continuation of Piteştilor Plain, to the south, representing a terminal piedmont plain (Posea Gr., 1974). Loess-like deposits appear in the lithological substratum of this plain; after the settling of these deposits, numerous depression areas have resulted, known with the name of saucers, which is also reflected in the denomination it bears. The area contained between the valleys of the Neajlov and Argeş rivers represents a lower compartment of this plain, with less developed soils (cambisols instead of luvisols). Evidence of certain Fig. 1.2. Digressions of the rivers recent streams changes within the hydrographical net on the Neajlov-Arge interfluve

70 The Annals of Valahia University of Târgovişte, Geographical Series, Tome 8 / 2008 ______also appear in this area. Thus, during the flood of 1941, the Argeş river communicated with the Neajlov river on two routes: one under the basis of the terrace from Stavropolia locality and the other in the north of Olteni locality. In 1972, the Argeş river recorded again very high flows and it was very close to reactivate its old connections with the Neajlov river.In the same year, the Izvor rivulet, a little tributary of the Neajlov river, flooded Stavropolia locality and became, for a short period, a tributary of the Argeş river. We have to mention here that the thalweg of the Neajlov river is lower than the one of the Argeş river. So, considering the aspects that have been presented above, the area between the Neajlov and the Argeş rivers can be considered as a passage area between the piedmont plain in the west and the subsidence plain in the east.

Statistical data over the relief units and subunits in Dâmboviţa County The surface The surface The relief unit The relief subunit Km² % Km² % I.1. Bucegi Mountains 160 4 I.2. Leaota Mountains 150 4 I. The mountain unit 357 9 I.3. The area between Ialomicioara 47 1 and The Sub-Carpathians The Internal 479 12 II.1. The Ialomiţei Sub-Carpathians Sub-Carpathians The External 421 10 II. The hill unit 1240 30 Sub-Carpathians II.2. The Sub-Carpathian area 43 1 with folded and monocline structure II.3. Cândeşti Piedmont 297 7 III.1. Târgoviştei Plain 741 18 III.2. Cricovului Plain 142 3 III.3. Ploieştilor Plain 45 1 III.4. Piteştilor Plain 273 7 III. The plain unit 2457 61 III.5. Găvanu-Burdea Plain 351 9 III.6. Vlăsiei Plain 376 9 III.7. Titu Plain 477 12 III.8. Ibrianu Plain 52 1 Total 4054 100 - 4054 100

The flaggy plains are newer than the piedmont plains and they are characteristic for the south-eastern side of Dâmboviţa County, where Vlăsiei Plain lies, realizing the passage between the piedmont plains and the proper flaggy plains, but having more specific features that are characteristic for the flaggy plains. Thus, the valley of the Colentina river, which is weakly outlined at the contact with Târgoviştei Plain, deepens and widens very much (1,0 – 1,5 km.) after only some km., at Ghimpaţi, presenting steep banks, abandoned branches, and becoming swampy from place to place, with gleysols and hygrophilous and hydrophilic vegetation; this situation is not met in the piedmont plains. All these specific features are evidence of a much amplified previous evolution; that is why the scientists advanced the idea that the valley of the Colentina river might be an old stream of the Dâmboviţa river or even of the Ialomiţa river (Vâlsan G., 1915). This plain has the following special features: its riverine and limnic origin, the presence of the loess deposits at the surface, the settling relief formed because of the pipping process (very many saucers) and the more reduced deepness of the ground water layer compared with Găvanu-Burdea Plain. One must also notice the presence of the soils in the class af chernozem (argic phaeozems), whose genesis has been very much influenced by the presence of the loess deposits.

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Within Vlăsiei Plain, on the alignment of Movila – Dârza localities, there is the contour line of 110 m., which marks the lowest altitude within Dâmboviţa County. The subsidence plains (Mihăilescu V., 1947), also known with the name of disgression plains (Vâlsan G., 1915) represent the newest relief units (superior Holocene) in Dâmboviţa County, which have been formed after the accumulation of fine alluvial deposits brought by the Argeş, Dâmboviţa and Ialomiţa rivers. In the central-southern side of Dâmboviţa County, there is Titu Plain, situated on the streams of the Argeş and Dâmboviţa rivers; in the eastern side, there is Ibrianu Plain (Posea Gr., 1988), situated on the stream of the Ialomiţa river, realizing the passage to another bigger subsidence plain, Săratei Plain. The relief of these plains bears the stamp of the subsidence phenomenon, taking the form of a low plain (120 – 160 m. high), with the aspect of a high river plain, which has been subjected to some intense silting processes. The rivers do not have terraces, and sometimes nor even river plain, so their bed comes into direct contact with the plain. Because of the very reduced slope, the rivers have very windy streams, which determines the degradation of the agricultural lands. The riverine micro-relief, represented by levees, abandoned valleys, depression areas, a.s.o., is frequently met. The uncertainty of the beds determines different denominations for the same stream of water. Thus, the Sabar river is also called Răstoaca, the Dâmbovicioara river is also called Spălătura, and, in the south of Mărunţişu, Valea Moartă is also known with the name of Secătura. The ground water layer is very close to the surface (2 – 3 m.), strongly influencing the soil and the vegetation. As a result, the gleysols covered with hygrophilous and hydrophilic vegetation are very spread. The alluvial soils and the vegetable cultures, which are associated to the above-mentioned gleysols, offer the specific note to this geographical landscape. Most of the geographical scientific works take into consideration the existence of a subsidence strip, at the basis of Târgoviştei piedmont Plain, connecting Titu Plain and Ibrianu Plain on the stream of the Ialomiţa river. Gr. Posea (1988) narrows very much this strip, whose limits are unclear, as a result of the mixture of the morphological features of Târgoviştei Plain with the ones of Vlăsiei Plain. V. Mihăilescu (1966) completely eliminates the above-mentioned strip, between the Dâmboviţa and the Ialomiţa rivers; thus, Târgoviştei Plain comes into a direct contact with Vlăsiei Plain. There are not more obvious changes in the relief of this sector; these changes occur in the soil layer and in the vegetation, as a result of the modification of the edaphic conditions. Thus, the alluvial soils and the eutric cambisols, covered with mesohygrophilous meadows, change to cambic or argic chernozems, which are generally wet at the level of the ground water; to the east, they change to argic or reddish preluvisols, covered with xeromesophilic meadows and oak forests. Because of all the above- mentioned aspects, the eastern limit of Titu Plain can generally be established on the alignment of Tărtăşeşti – Răcari – Crângaşi (Conţeşti) – Băneşti (Sălcioara) localities. In conclusion, the reddish preluvisols, the typical luvisols, the ground water layer situated at further depths, the xeromesophilic meadows and the oak forests, which are all characteristic for the interfluve between the Ilfov and the Ialomiţa rivers, sustain the reasoning that there is not an area of continuous subsidence (even a very narrow area) to realize the passage from Titu Plain to Ibrianu Plain, on the stream of the Ialomiţa river.

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BIBLIOGRAPHY

Bugă D., Zăvoianu I., 1974, Judeţul Dâmboviţa (Dâmboviţa County), Ed. Academiei, Bucureşti; Ispas Şt., 2001, Câmpia Titu – Studiu pedogeografic (Titu Plain – pedogeographical study), Ed. Macarie, Târgovişte; Mihăilescu V., 1947, Cursuri 1945 – 1946 (Courses 1945 – 1946), Institutul de Cercetări Geografice al României, Bucureşti; Mihăilescu V., 1966, Dealurile şi câmpiile României (Romania’s hills and plains), Ed. Ştiinţifică, Bucureşti; Murătoreanu G., 2008, Munţii Leaota, studiu geomorfologic (Munţii Leaota, a geomorphology study), Teză de doctorat, manuscris, Institutul de Geografie, Bucureşti; Niculescu Gh., 1960, Câmpia piemontană înaltă a Cricovului Dulce (Cricovului Dulce high piedmont Plain), Probleme de Geografie, vol. VII; Popp N., 1938, Terasele fluviatile ale Munteniei Centrale (Les terrasses fluviatiles de la Muntenie Centrale), B.S.R.R.G., tomul VII, Bucureşti; Posea Gr., Badea L., 1984, România-unităţile de relief (Romania – the relief units), hartă, Sc.1:750000, Ed. Şt. şi Enciclop., Bucureşti; Posea Gr., 1988, Contactul câmpiilor Vlăsiei şi Târgovişte – Ploieşti (The contact of Vlăsiei and Târgovişte – Ploieşti plains), Prob. de Geom. României, Univ. Buc, II; Velcea Valeria, 1961, Masivul Bucegi, Studiu geomorfologic (Bucegi Massif. Geomorphological study), Ed. Academiei, Bucureşti; Velcea Valeria, 1982, Geografia Carpaţilor şi Subcarpaţilor româneşti (The geography of The Romanian Carpathians and Sub-Carpathians), Ed. Did. şi Ped. Bucureşti; Vâlsan G., 1971, Opere alese (Selected scientific works), Ed. Şt., Bucureşti; ***, 1982, Enciclopedia geographică a R.S. România (S.R. of Romania’s geographical encyclopaedia), Ed. Şt. şi Enciclop., Bucureşti; ***, 1987, Geografia României, vol.III, Carpaţii Româneşti şi Depresiunea Transilvaniei (Romania’s Geography, III-rd volume, The Romanian Carpathians and The Depression of Transylvania), Ed. Academiei, Bucureşti; ***, 1983, Harta hidrografică a Judeţului Dâmboviţa (The hydrographic map of Dâmboviţa County), I.G.F.C.O.T Bucureşti, Sc.: 1:200 000; ***, 1997, Topographic maps at the scales of 1:100000 and 1:50000, D.T.M., Bucureşti.

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