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The Apuseni Mountains
Romania
Written by
Alexandra Spiridon
1
Romania – Overview
Romania is situated in the south-central region of Europe (between 20° 15’ 44’’ – 29° 41’ 24’’ E longitude
and 43° 37’ 07’’ – 48° 15’ 06’’ N latitude). The climate is transitional. In central and western regions of
Romania (within the arc of the Carpathian Mountains) there is a temperate, central- European climate; towards
southwestern Romania a sub – Mediterranean climate is characteristic. The northern and eastern regions of
Romania are under the control of a continental climate. To these main categories of climate must be added the
subalpine and alpine climates of the Carpathian Mountains.
These climatic influences have engendered great diversity among the fauna, flora and vegetation of
Romania.
Romania's natural landscape is almost evenly divided among mountains (31%), hills (33%), and plains
(36%). These varied relief forms spread rather symmetrically from the Carpathian Mountains, which reach
elevations greater than 2,400 m, to the Danube Delta, which is just a few meters above sea level. The arc of the
Carpathians extends over 1,000 km through the center of the country. These mountains are of low to medium
altitude and are no wider than 100 km. They are deeply fragmented by longitudinal and transverse valleys and
crossed by several major rivers. Another feature is the multitude of eroded platforms at relatively high altitudes,
which often host permanent settlements.
Romania's Carpathians are differentiated into three ranges: the Eastern Carpathians, the Southern
Carpathians or Transylvanian Alps, and the Western Carpathians. Each of these ranges has important
distinguishing features.
The Eastern Carpathians are composed of three parallel ridges that run from northwest to southeast. The
westernmost ridge is an extinct volcanic range with many preserved cones and craters. The range has many
large depressions where many towns can be found. Important mining and industrial centers as well as
agricultural areas are found within these depressions. The Eastern Carpathians are covered with forests – around
32% of the country's woodlands are there. They also contain important ore deposits, including gold and silver,
and their mineral water springs feed numerous health resorts.
The Southern Carpathians offer the highest peaks at Moldoveanu (2,544 m) and Negoiu (2,535 m) and more
than 150 glacial lakes. They have large grassland areas and some woodlands but few large depressions and
subsoil resources. Numerous passes and the valleys of the Olt, Jiu, and Danube rivers provide routes for roads
and railways through the mountains.
The Western Carpathians are the lowest of the three ranges and are fragmented by many deep structural
depressions. They are the most densely settled, and it is in the northernmost area of this range, the Apuseni
Mountains, that permanent settlements can be found at the highest altitudes.
Enclosed within the great arc of the Carpathians lie the undulating plains and low hills of the Transylvanian
Plateau—the largest tableland in the country and the center of Romania. This important agricultural region also
contains large deposits of methane gas and salt. To the south and east of the Carpathians, the Sub – Carpathians
form a fringe of rolling terrain ranging from 396 to 1,006 m in elevation. This terrain is matched in the west by
the slightly lower Western Hills. The symmetry of Romania's relief continues with tablelands and plains to the
south and east of the Sub-Carpathians. The Sub-Carpathians and the tableland areas provide good conditions for
human settlement and are important areas for fruit growing, viticulture, and other agricultural activity. They
also contain large deposits of brown coal and natural gas. The plains are rich with chernozemic soils and form
Romania's most important farming region. Irrigation is widely used, and marshlands in the Danube's floodplain
have been drained to provide additional tillable land.
Romania's lowest land is found on the northern edge of the Dobruja region in the Danube Delta. The delta is
a triangular swampy area of marshes, floating reed islands, and sandbanks, where the Danube ends its trek of
almost 3,000 km and divides into three frayed branches before emptying into the Black Sea. The Danube Delta
provides a large part of the country's fish production, and its reeds are used to manufacture cellulose. The region
also serves as a nature preserve for rare species of plant and animal life including migratory birds.
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2
Apuseni Mountains
The Western Carpathians comprise a large block of mountain country between the Pannonian Plain and
Transylvanian Plateau, roughly 170 km in east – west extent (Siria in Arad County to Turda in Cluj County) and
150 km north – south (Zalau in Salaj County to Deva in Hunedoara County) (Figure 1). The mountains are of
no great height except for a central area comprising the Bihor, MunteleMare and Vladeasa Mountains where
there are several peaks higher than 1800 m.
There are sharp geological contrasts with crystalline schists, limestones and volcanic rocks all very
prominent; generating remarkable scenic variety with the gorges (Cheile Turzii, Ordincusa and the Upper Aries)
and karstic plateaux of the limestones particularly outstanding. In particular, the Padis- Cetatile Ponorului karst
at 1100–1640 m, with its fine scenic approaches like the Cobles Valley, contrasts with impermeable
sedimentary rocks to the south. Geological variety leads to biodiversity: the area offers a veritable synthesis of
Romanian fauna while rare plants include some 15 species of orchids found in the karstic zone of OcoaleScarisoara.
The Bihor Mountains form the basis of the hydrographic system, providing the springs of such major river
systems as the Aries, Cris, Somes and Mures. Many of the valleys have been described as wild and inhospitable,
because of landslides, which frequently block roads, and serious floods. Extensive woodland clearances have
been made and the settlement pattern is remarkable for its high degree of dispersal especially in the upper
sections of the Aries where the ‘Platforma Ariesului’ or ‘Platforma Tarii Motilor’ still retains a large
population.
2.1
Geologic evolution and situation
Fig 1. General outline of the Apuseni Mountains, showing the main geographical subdivisions and the geological
division between N Apuseni and S Apuseni.
Based on their different pre-Alpine geological evolution, the Apuseni Mountains can be divided in two main
structural units, the North Apuseni (Highis-Drocea, Codru-Moma, Bihor, Gilau, Padurea Craiului, Vladeasa,
Plopis, Meses Mountains) and the South Apuseni (Metaliferi and Trascau Mountains) (Fig. 1).
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The North Apuseni Mountains are composed of various basement tectonic units, made up of Early
Proterozoic metamorphic rocks (mostly from high-grade metamorphic sequences) and associated granites (Late
Cambrian ~502–490 Ma, Middle to Late Devonian ~372–364 Ma and Early Permian ~278–264 Ma), with a
Permo-Mesozoic sedimentary and volcanic cover.
The southern basement units of The North Apuseni Mountains record only younger Alpine events, in a northvergent thrusting shear zone and concomitant low-grade metamorphism, which marks the separation of North
and South Apuseni.
The South Apuseni Mountains (SAM) include Middle Jurassic ophiolites, Late Jurassic calc-alkaline volcanic
rocks and Late Jurassic to Late Cretaceous sedimentary deposits. The SAM include the largest ophiolitic
sequence of the Carpathians, determined as a prolongation of the Vardar zone of the Dinaric ophiolitic belt,
from which they are now separated by South Transylvanian fault system. Calc-alkaline effusive and intrusive
rocks pierced the ophiolitic basement during Late Jurassic times.
In the Apuseni Mountains rocks range from basaltic-andesites to dacites, with subordinate trachyandesites and
associated intrusive varieties. Andesite is the most common rock-type.
Basaltic andesites are present in the Zarand and Baia de Aries area (Detunata hills). These rocks are slightly
porphyritic, with plagioclase, augite, olivine, resorbed amphibole microphenocrysts and microlites of
plagioclase and augite, magnetite, ilmenite, olivine, resorbed amphibole and glass in the groundmass.
Andesites display the largest spectrum of varieties according to texture and phenocryst content. The most
common are: (1) Two-pyroxene andesites (occurring in the Zarand area). The rocks are normally porphyritic
and contain plagioclase, clino- and orthopyroxene phenocrysts, generally showing corroded and opaque rims;
(2) Amphibole ± pyroxene andesites are present, mostly in the eastern half of the outcropping sector (Bucium,
Brad and Zlatna areas). They are largely porphyritic and have plagioclase, amphibole, clino-orthopyroxene, and
sometimes, corroded quartz and accessory Fe-Ti oxides, apatite, zircon, sulphides and Cr-spinels. Rare garnet
can be found at Zlatna, Bucium and in the Brad areas within this type. (3) Amphibole-biotite ± pyroxene
andesites occur in the Sacaramb, Deva and Baia de Aries areas. The rocks are largely porphyritic and principal
phenocrysts are plagioclase, quartz, amphibole, biotite, two pyroxenes and the same accessory minerals as for
the amphibole ± pyroxene andesites.
The different types of andesites are generally specific to each individual area, with two pyroxene bearing
varieties in the west (Zarand), and more acidic, amphibole- and biotite-bearing varieties in the east (BradZlatna, Baita – Sacaramb). Amphibole-pyroxene andesites occur mainly in Zarand, Brad and Zlatna areas. The
large presence of hydrous minerals together with the calc-alkaline characteristics of the rocks emphasises the
significant involvement of water in the generation of magmas.
Dacites have been described at Rosia Montana area or as clasts in volcano - sedimentary deposits. Even if the
rocks keep their coarse porphyritic textures and a phenocryst assemblage of plagioclase, quartz, biotite and
minor amphibole is observed, they are nevertheless hydrothermally altered (e.g., adularized at Rosia Montana).
The attributed name of these rocks is based only on petrographic observations and cannot be proved by
petrochemical data (as requested), because the rock is hydrothermally altered.
Dacitic composition may occur by the transition of some amphibole-biotite ± pyroxene andesites, richer in
quartz, at Baia de Aries and Sacaramb areas.
Trachyandesite occur in the Sacaramb area (Zambrita) and in an isolated occurrence near Deva (Uroi).
Zambrita trachyandesite is slightly porphyritic, and contains plagioclase, amphibole, two pyroxenes, biotite and
quartz as micro-phenocrysts in a fine groundmass along apatite, zircon, magnetite, ilmenite and Cr-spinels. The
Uroi trachyandesites display a disequilibrium mineral assemblage containing Ti-augite, hypersthene, amphibole
and biotite phenocrysts and accidental quartz xenocrysts, many with reaction rims.
The intrusive varieties can be described as microdiorites and they have the identical mineralogical assemblage
as the extrusive varieties. Most are, however, affected by processes of hydrothermal alteration. An exception is
a microdiorite in Sacaramb area (Paraul lui Toader), which is an alkaline variety. It contain several generations
of plagioclase, amphibole substituted either by clinopyroxene or an aggregate of clinopyroxene, plagioclase,
quartz and biotite, fresh amphibole, clinopyroxene along apatite, zircon, magnetite, ilmenite and sulphides as
accessories.
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2.2
Resources
The Apuseni Mountains don’t hold any significant energy resources but they are very rich in non – ferrous
minerals and building materials (mainly igneous and metamorphic rocks but not only). In Brad basin brown
coal is extracted, which is mostly used in thermal power plants. At the northern part of the mountains lignite
(Barcau basin) and brown coal (Almaiului basin) are extracted.
Hydro – energetic resources are used only partially for hydro – electric power plants situated along Somesul
Mic, Iada and Dragan rivers. Iron is extracted from Muntele Mare (Baisoara) and Gilaului Mountains and the
production, though small, places this area on the second place as an iron source after Poiana Rusca Mountains.
Gold and silver extraction goes back in history. Ever since Roman occupation the main production centers
have been Zlatna and Rosia Montana. Today Zlatna mine is a source for pollution on the rivers nearby and the
ecosystems link to them, and Rosia Montana is under pressure of becoming a major environment threat with
cyanide if mining starts again. Other extraction points for gold and silver include Baia de Aries, Bucium, Baita,
Musariu and Criscior. Of course as all mines these too cause damage to the environment but not as much as the
first two.
Bauxite is extracted from Padurea Craiului Mountains at Varciorog, Rosia, Dobresti, Zece Hotare and is
processed nearby (Dobresti and Chistag) at first. Afterwards it is taken to Oradea to be turned into aluminum
oxide.
At Izvorul Ampoiului there are extraction points for mercury and at Baita for molybdenum.
Copper, lead and zinc are extracted at Baita, Sacaramb and Rosia Poieni.
Production and repairing centers for mining equipment and vehicles include Brad and Stei (major ones).
Other metallic products are obtained at Huedin and Sebis. Sulfuric acid, whetting materials and electro
chemicals are produced at Zlatna.
Due to the geological setup of the area, the industry of extraction of construction materials is largely spread.
The following rocks are extracted:
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•
•
•
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Granite (at Radna, Zam, Savarsin), basalt (at Branisca) and andesite (Vata de Jos, Varfurile)
Marble (at Moneasa, Vascau)
Travertine (at Banpotoc)
Fire clay (Alesd, Aghires), kaolin (Aghires), diatomite (Minisu de Sus, Zarandu Mountains), sandstone,
etc
Limestone (at Sandulesti, Alesd, Baita for cement factory in Chiscadaga)
The large area covered with forests and their diversity favored the development of wood processing industry
in small centers (Campeni, Huedin, Beius, Brad, Stei, Sebis etc.), which offer semi processed wood materials to
major industrial centers (Arad, Gherla) or furniture factories (Oradea, Cluj-Napoca, Aiud, Turda, Zalau).
Although many of regions don’t have land good for farming, they allow other major activities as animal
rearing (cows and sheep mostly).
Last but not least the Apuseni Mountains have a remarkable potential as a tourist attraction.
The Apuseni contain great geological variety, offering a range of ores (non-ferrous, gold-silver and bauxite)
as well as building materials. Given the climatic conditions there is a copious amount of water supply and flora,
with some
alpine-arctic characteristics. Scenery is most varied and spectacular in limestone areas with dry valleys, steep
slopes and precipices, gorges like Cheile Turzii and Intregalde, Ordancus and Ramet; numerous caves including
several with fossil ice (Ghetarul de la Scarisoara and others including Bârsa, Focul Viu and Zgurasti). The karst
of Padis (Cetatile Ponorului) is outstanding with its portals, galleries, lakes, waterfalls and rocks. The gorges are
notable for their birds; with Cheile Intregalde and Cheile Râmetilor frequented by eagles as well as
woodpeckers and woodlarks. The relief is fragmented; yet there are extensive surfaces.
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2.3
Environmental problems and possible solutions
The Apuseni Mountains are remarkable in terms of landscape, biodiversity and culture. Despite the expansion
of settlement at high levels, with consequent deforestation, human activities have been broadly sustainable. Yet
dislocations are now severe and there are also development threats, which require attention and taking action.
While mining is a traditional activity, the large scale of development under communism led to severe pollution
problems in the Ampoiu and Aries valleys. Action is now being taken, especially at Zlatna; yet expansion of
activity at Rosia Montana using cyanide to process mine waste creates new threats for the future. Meanwhile,
the decline of mining and manufacturing (closure of textile industries) has left many households without
salaries and some forest and pasture zones are coming under heavy pressure from farmers seeking alternative
sources of income. These problems are being addressed but it’s a long way to go until serious protection
measures will be taken.
Acid rain containing chlorine and sulphur pollutes soil and water. The concentration for chlorine and sulphur
reached alarming levels at Zlatna due to mining pollution. Heavy metal pollution involves mainly cadmium,
chromium, copper, iron, lead and zinc. Mining pollution affects the Ampoiu and Abrud/Aries rivers and is a
major facet of water pollution in the wider area of Alba County. The Abrud river is permanently polluted with
water from mining galleries at Bucium Izbita – containing metallic ions – and the preparation plant at Gura
Rosiei. Then there is pollution from the Abrud mining enterprise and prospecting galleries in the Musca valley,
followed by the Baia de Aries installations lower down, concerned with the production of gold and silver ores.
There is also a particular hazard of cyanide released from the pit at Baia de Aries (a centre of gold and silver
production). As a result many fish die and drinking water at Turda is affected.
Although mining has been declining through closures, there are continuing risks because gold production in
the Apuseni may be enhanced by the process of cyanide leaching. Pouring potassium cyanide over low grade
ore means that virtually the entire gold content can be obtained: a very great advance over traditional methods
which secure only 0.7–1.7 g of gold from each tone of ore mined at Rosia Montana today. The system was
pioneered by the Australian company ‘Esmeralda’ and used in Romania at Baia Mare (with disastrous results
when cyanide spilled into the Tisza drainage system in 2000) but it is still considered feasible provided that
adequate environmental safeguards are taken. Today, Gabriel Resources owns 80% of the mine and their
mining project faces the environmental challenge of rectifying two thousand years of aquatic and other forms of
pollution in accordance with Romanian laws, EU guidelines and World Bank standards using state of- theindustry internationally accepted mining and treatment practice.
Although mining is the most pressing problem it is not the only one. In Padis and the upper Aries the
environment is quite unstable due to heavy pressure through agriculture, woodcutting and tourism. All this
favored flood risks at times of great rainfall and land sliding. The Romanian government has drawn up a
recovery plan with emphasis on constant monitoring of rain and snowfall and river levels. As for the major
deforestations, a number of geoparks and protected areas have been set up. Some were successful, some not,
mainly because of illegal woodcutting.
Today there are over 100 natural reserves (botanical, geological, hydrological, speleological and
palaeontological) and individual monuments of nature. Caves are of great importance for both conservation and
tourism development, especially for individuals and small groups, provided that care is taken to avoid polluting
underground water and collecting ‘souvenirs’. Despite their remoteness, more caves could be opened up, like
Coiba Mare, Coiba Mica and Huda Orbului and, where local authorities do not have the resources, caving clubs
(like ‘Clubul de Speologie “Sfinx” Gârda’ and ‘Crysis Oradea’) are much involved in regulating public access –
marking trails and providing information and emergency medical assistance – while controlling abuses such as
dumping rubbish, camping and cutting wood in reserves and buffer zones.
The Apuseni Mountains demonstrate very clearly the need for reclamation to cope with pollution problems
arising from mining activity and the processing of minerals. Equally, it is evident that biodiversity conservation
must the combined with sustainable solutions to problems of local community development. In both cases
initiatives have been taken by government since 1989 but the resources available have been modest and the
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necessary contact with the local population has not been maintained, partly because the communities
themselves are not adequately organized. ENGOs (Environmental Non-Governmental Organizations) have
played an important role with both types of problem, maintaining a diverse range of activities to protect both
people and natural resources.
Yet influence of the ENGOs is limited. While they are doing effective conservation work as well as
supporting communities and maintaining a degree of coordination, there is not enough consistency in the way
that environmental issues impinge on the working of central government.
2.4
Geoparks and natural reservations
The most important geopark is Apuseni National Park. (Fig.2)
Fig. 2. Apuseni National Park and its natural reserves
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•
“Ghetarul de la Scarisoara” Cave – is the biggest cave in Romania and it has a mass of 75000 m3 of ice.
•
“Ghetarul de la Vartop” Cave - is a Speleology Reserve and it can be visited just in the presents of a
guide. It is declared a monument of the nature, because of its beautiful colors and the fairy tale feeling.
• Detunata Basalt Columns - The Geological Reservation formed by two peaks of volcanic basalt: The
Necked Detunata and The Fleecy Detunata that lay in the Metaliferi Mountains contain basalt columns on
a surface of 5 ha. The columns of basalt have a height that goes until 200m.
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•
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The Scarisoara Belioara Botanical Reservation - The reservation has a surface of 450 ha and shelters
various species of rare plants (The grapes of the Bear, The Blood of the Stalwart) and animals.
The Natural Reserve of Ponorului Fortress – The Ponorului Fortress Basin has 8 basins that can
communicate just under the soil. The region is very rich in karst systems, like caves (one of the most
interesting being the one named “Ghetarul Focul Viu “ - Glacier of the Living Fire), gorges, dolinas.
•
Cheile Turzii (Turzii Gorges) - The Natural Reservation gives an extraordinary carstic view (gorges,
caves, towers, walls) that shelter a rich and various vegetation, the number of the species (1000 at least)
considered the biggest from Romania.
•
Padis Plateau - Natural reservation with karst phenomena unique in Romania (Boghii Rocks, "Living
Fire" Glacier, Golden Valley, Ponor Citadels, "The Lost World" plateau, Radesa citadels – some of them
already presented above)
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References
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Dumitrescu, I., Sandulescu, M. (1976): Harta Tectonica a Romaniei (Tectonic map of Romania), in Geological Atlas
of Romania, Geological Institute of Romania.
Sandulescu, M. (1984): Geotectonica Romaniei (Geotectonics of Romania). Ed. Tehnica, Bucuresti. 336pp.
Seghedi, Ioan: Evolutia geologica a Muntilor Apuseni (Geological Evolution of Apuseni Mountains), Alba Iulia,
Romania, 2004
www.rmgc.ro - Rosia Montana Gold Corporation
Ianovici V., 1976: Geologia Mun¸tilor Apuseni. (Geology of the Apuseni Mountains) Editura Academiei RSR,
Bucharest.
Buza, M., Dimen, L., Pop, G., Turnock, D.: Protectia mediului in Muntii Apuseni. Rolul organizatiilor nonguvernamentale de protectie a mediului. (Environment protection in Apuseni Mountains. The role of ENGOs)
Pictures taken from: www.geoturism.ro, b00r.tripod.com/ CheileTurzii/cheileturzii1.html,
www.pensiuneaalbaceana.ro, www.padureacraiului.dap.ro
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