. The Parâng Mountains consist predominantly of crystalline rocks, peripherally covered with patches of sediments from the Paleozoic, Mesozoic and Cenozoic eras, mixed with large areas of granite outcrops. On the southern slope, sedimentary rocks from the Mesozoic era can be found, more exactly massive limestone from the Jurassic period. The newest rocks are found on the southern frame of the mountains and in the north-west, where it is bordered by the Petrosani Depression. The nature of the rocks favored the emergence of bulk, rounded ridges, separated by deep valleys. The mountains present an overall asymmetry, with the northern front more steepen, with short ridges, while the southern facade is less inclined and with longer ridge. Especially in the southern part, the slopes are composed of several steps.
Climate
Temperatures
The general layout of the main ridge on a west-east axis and its altitudes of over 2000m makes the Parâng mountains an orographicdam in the way of the air masses that flow on the north to north-west and south to south-west directions. Also, the asymmetry of the main ridge, with the steep side to the north, leads to the receiving of different amounts of heat and moisture, more on the southern side. The sun shines approximately 1800–2000 hours/year, the highest temperatures being recorded in July and August. The average annual temperature is 6 °C at the bottom of the mountain and 0 °C at altitudes around 1800m. Above 2000m, the average temperature is below 0 °C. The difference between the recorded average temperatures of the southern and northern slopes is around 1-2 °C.
Precipitations
The average annual rainfall is between 900 and 1200mm. The most abundant rainfall is recorded around the altitude of 1600m to 1800m. June is the month with the highest precipitations, 110mm at the bottom of the mountain and 160mm at altitudes over 1500m. It snows on average 90 days per year above the altitude of 1500m. The first snow comes during the first half of October, while the last one during the first half of May or late April at lower altitudes. At high altitudes the snow is present on average for 200 days each year. The thickness of the snow layer depends on the weather conditions, the exposure of the slopes to the winds, exposure to the sun, snowfall etc. At over 1500m, the average thickness is greater than 1m.
Wind
The wind intensity is high all around the year. Above 2000m, the westers winds are dominant, while below this threshold, the wind direction and intensity are influenced by the mountain relief. Above 2000m, the average wind speed is 8–10 m/s. During the cold season, the wind speed may reach 15 m/s and above on some ridges.