Geomorphological map of the central part of the Parang Mountains. Gheorghiu et al. Materials and methods The field area extends between m and m altitude. We used topographic maps ;Google Earth highresolution imagery and orthophotmaps 50 cm resolution to identify glacial features on the north-eastern slopes of source area of the Lotru valley Fig.
Glacial landforms were difficult to map because of the heavily forested area at lower elevations in the Lotru valley. The glacial landforms were initially mapped and sampled after field observations. We collected 24 samples for 10Be dating in quartz from boulders on moraines in 4 cirques North Mohoru — 2 samples; Zanoaga Pietroasa — 6 samples; Galcescu — 6 samples; Zanoaga Mare — 7 samples and in the upper part of the Lotru Valley 3 samples Table 1.
The position, altitude, topographic shielding, dimension of boulders were recorded in the field Table 1. Maximum 3 cm were removed from the boulder upper surfaces which were carefully selected to minimize any potential impact of rolling from cirque walls, overturning or shielding. Topographic shielding factor was determined for all the surrounding mountain slopes at each of the sampled localities Dunne et al. Details of sample locations and relevant analytical data are given in Table 1.
The 10Be ages were calculated with the Cronus Earth online calculator v. The calculated age uncertainties are expressed as ±1s Table 1.
The minimum exposure ages are calculated assuming zero erosion rates for the sampled surfaces since deposition. Geomorphological setting The results of our geomorphological mapping in the central Paraang Mountains is shown on Fig.
Based on the morphologic and morphometric characteristics, there are two types of cirques in this upper part of the Lotru Valley: femei frumoase din Oradea care cauta barbati din ClujNapoca with quasi-horizontal floor located at — m towards the higher end of the valleys, likely pre-glacial, and smaller hanging cirques on the side walls at — m altitude.
Zanoaga Pietroasa cirque The Zaanoaga Pietroasaa cirque is located in the easternmost part of our study area, on a south-north direction, and is drained by the Iezer rRver Fig. In spite of a large accumulation area, there is no defined cirque at the higher end of the valley. Here, the river has been eroding headwards, most likely post-glacially. The side walls of the Zaanoaga Pietroasaa cirque are generally steep, and frost-shattered material has rolled down to the bottom of the walls, a process which is still active today.
The western Jura site ul gratuit de dating wall of this glaciated area shelters a smaller glacio-nival cirque in the south, with a very asymmetric transverse profile. It is a highly degraded area due to active ravines throughout. To the north, a small hanging cirque is an indication of a former accumulation area that fed into the main glacier of the lezer valley Fig. The cirque's floor is located at — m altitude, ~40 m above the main valley floor. Evidence of glacial erosion is indicated by a reverse slope on the floor of this cirque, covered with frost-shattered material Fig.
The rest of the western wall is very steep up to m in height and cut by a deep rock chute towards the north Figs. The eastern side wall indicates very active slope movement processes, with numerous talus cones at the bottom. The most highly developed cirque in the lezer valley is located at — on the northern side of the Mohoru peak mhere named the North Mohoru cirque.
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This glacial cirque has a typical amphitheatre shape with a north-eastwards direction. The main lezer valley is covered in a series of glacial deposits on a m long and m wide surface which the river has mildly incised since glacial retreat.
The most notable glacial landform is located along the eastern valley side ~ m long Fig. This landform was probably deposited as a lateral moraine, Jura site ul gratuit de dating very steep ice-proximal sides and mild ice-distal slopes.
The top of the moraine has been extensively modified into several arched features through the continuous addition of frost-shattered Jura site ul gratuit de dating from the side wall, especially towards the southern part where valley side walls are closer. Further down valley, a clear reverse slope has been formed through intense glacial erosion, just before the glacial threshold that separates the lezer upper valley from its lower part towards the Lotru valley.
Material transported by the river postglacially has filled more than half of the lake surface and its former extent can be easily traced.
The moraine has been deeply incised by the lezer river during the Holocene. Above the confluence of the Coasta Pietroasei and the lezer rivers there is a lateral moraine deposit ~4—5 m above the valley floor. The deposit dips ° northwards and is covered in semi-rounded and semi-angular boulders of variable dimensions up to 4 m a-axis.
Galcescu cirque complex The Galcescu cirque complex is located in the western part of our study area, in a south-west to north-east orientation Figs. To the east, it is separated from the lezer valley by the Galcescu Ridge.
На крыше главного служебного здания АНБ вырос лес из более чем пятисот антенн, среди которых были две большие антенны, закрытые обтекателями, похожими на громадные мячи для гольфа. Само здание также было гигантских размеров - его площадь составляла более двух миллионов квадратных футов, вдвое больше площади штаб-квартиры ЦРУ.
The western limit is made by the Pietroasa Ridge, a secondary ridge extending from the main ridge m in the south towards Pietrele peak m in the north. Glacial erosion and deposition processes left a very detailed glacial imprint in all these cirques. The cirques are located on two different levels. The lower cirques — m are very well-developed and consist of 2—3 reverse bed slopes in which lakes have formed.
The higher cirques — m are smaller and with a typical amphitheatre shape. The Caaldarea Dracului is a hanging cirque located below the Setea Mare m and Setea Mica m peaks and it is separated from the Zaanoaga Mare cirque by the glacial transfluence Table 1 Sample characteristics, 10Be concentrations and calculated surface exposure ages.
They assume zero erosion, scaling factors according to Stone and a spallation production rate of 4. Exposure ages are presented with the external uncertainties internal uncertainties in brackets.
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The amount and type of the debris indicate that the steep side walls are very active and provide lots of frost-shattered material to the talus cones below. On the south-east wall a large rock chute is the main contributor to the material accumulated below. Various glacial deposits are found at the bottom of this cirque and on the high step towards the Galcescu cirque, deposited as ice flew downwards. The Gaalcescu cirque is larger and located approximately m below the Caldarea Dracului Fig.
The Galcescu cirque is surrounded by high steep walls in the southern and south-eastern part towards the Setea Mare peak and the Gaalcescu Ridge where talus cones are still actively forming. There are two glacially deepened basins: one basin occupied by Pencu Lake 0. All lakes are limited by frontal glacial moraines at their northern end. On the eastern side of the lakes, lateral moraines were deposited along the cirque floor.
They can be traced up along the eastern side of the cirque to the frontal moraines in front of the Galcescu Lake.
The Zanoaga Mare cirque is located at — m altitude between the Paasaari Ridge to the south-east and Pietroasa Ridge to the north-west Figs. There are widespread areas covered with frost-shattered material at the base of the steep cirque walls, especially in the southern and south-western part of this cirque, and partially covered in vegetation.
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The Zanoaga Mare cirque is the most representative for the glaciated environment in our study area. It is a wide and shallow cirque that was likely the major ice accumulation area feeding into the main Lotru valley glacier.
Moreover, the large amounts of glacially polished areas on the lower south-eastern side walls and the elongated ice moulded bedrock are a good indicator of the direction and intensity of the ice flow Figs. The Zanoaga Mare cirque comprises one of the most representative erosional and depositional glaciated areas of the Southern Romanian Carpathians.
Based on altitude and morphology, the Zanoaga Mare cirque can be divided into a western and an eastern compartment. The western compartment is smaller and matrimoniale nehoiu femei at higher altitude ~ m. Ice moulded bedrock in the form of roche moutonnées and whalebacks are typical for this part of the cirque Fig.
A lateral moraine deposited along the northern wall indicate the last ice flow towards the wider eastern compartment of the Zanoaga Mare cirque, located ~ m lower Fig. It continues further down with another moraine that blocked Zaanoaga Mare Lake 0. Towards the cirque headwall, a series of arched moraines Jura site ul gratuit de dating as evidence for the last glacial activity in the Zanoaga Mare cirque.
A well-developed protalus rampart is located in the upper part of the moraines Fig. This arcuate ridge developed along the lower margin of a snow slope. Glacial deposits are widespread along the entire cirque floor and massive boulders of various dimensions have been abandoned on top of the deposits, especially in the middle part of the cirque. Two former ice flows are clearly visible in this lower part of the Zanoaga Mare cirque towards the Lotru Valley, separated by an elongated ice moulded bedrock feature whaleback Fig.
Lotru valley The Lotru valley is formed at ~ m by the confluence of the lezer and Galcescu streams Fig. Its high complexity in the Fig. Glaciated environment in the Parâng Mountains. Dashed lines indicate moraines, solid lines mark the glacial thresholds, double dashed lines delineate protalus ramparts. The middle and lower sector of the Lotru valley is heavily forested, thus the glacial deposits are very difficult to identify.
Unfortunately, ground Jura site ul gratuit de dating of most of the published glacial record at lower altitudes has been impossible after the building of a major storage reservoir at Vidra.
Results The details of each sample collected in the Paraang Mountains and the 24 surface exposure ages are presented in Table 1.
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All surface exposure ages in Table 1 are presented with both uncertainties, however, in the discussion the internal uncertainty is used as all samples come from a small area with no significant difference in the 10Be production rate.
Eight samples taken from three moraines in the cirques of the Iezer valley have a range of 10Be ages from The down valley moraine in front of Iezer Lake the Jura site ul gratuit de dating Pietroasa cirque yielded exposure ages of The probability density plot suggests a tight cluster around a weighted mean of Further up, the moraine located along the Iezer eastern valley wall yielded exposure ages of 6.
The scatter of exposure ages confirms the mixed origin of this D. The oldest age of We tentatively assigned a deglaciation age consistent with the rest of the ages produced from samples located in front of the Iezer Lake see above.
The two younger ages of 6. Boulders on another moraine in the North Mohoru cirque were deposited at Six samples were collected from around the lakes in the Gaalcescu cirque with ages suggesting deposition at Given the size of the boulder 7 m a-axisit is very likely that the boulder deposited at Pre-exposure on a rock cliff and transport on top of ice surface are likely the causes for the inheritance of nuclides in this boulder, here considered an outlier.
According to the probability density plot the other five ages are tightly clustered around a weighted mean age of Above m altitude, seven boulders spread throughout the Jura site ul gratuit de dating Mare cirque were exposure dated to The last five samples produced from the moraines in this cirque come from a widespread moraine complex and it is unlikely to have been covered.
The younger two ages of Three samples from boulders in the Lotru valley yielded exposure ages of All boulders were well embedded into the surface and unlikely Jura site ul gratuit de dating have suffered any modifications since their deposition. Discussion 6. Chronology of deglaciation in the Parang Mountains During the last glaciation Würm, —11 kathe Carpathian cirques were excavated and deepened by glaciers.
They were subsequently filled with glacial sediments which stand as evidence of a reshaped and very diverse landscape. Previous studies in the Parang Mountains identified repeated glaciers advances and recessions during the last Quaternary glaciations e.
In this part we present our interpretation of field evidence and the deglaciation chronology obtained with the surface exposure dating of moraine boulders.
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We found no evidence of glacial deposits in the lower Lotru valley during our field season below m altitude. However, this valley has been extensively modified through incision of the Lotru river, especially in its middle sector especially around m altitudeand any evidence was likely removed during the Holocene period.
No suitable sites for cosmogenic nuclide surface exposure dating were found here. During the Late Glacial, the downwasting of ice in the upper valleys and cirques of the Parang Mountains Figs. At These boulders are part of a deposit likely formed by the glacier flowing down from the North Mohoru cirque Figs.
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At roughly the same time, ice in the Iezer valley had already withdrawn towards the higher ground. In the Zanoaga Jura site ul gratuit de dating cirque, this southward retreat of glacier caused the deposition of the moraine that blocked Fig. Probability density plots for the exposure ages obtained from glacial landforms. The ages are given with their analytical uncertainty.
Да вроде бы, - смущенно проговорил Беккер. - Это не так важно, - горделиво заявил Клушар.
Meanwhile, the glacier was not only retreating upwards but was also gradually narrowing towards the middle of the valley, as suggested by the deposition of the lateral moraine at This lateral moraine is covered with various boulders, mostly embedded in its surface especially towards its northern part Fig. It is well documented that rock slope failures often occurred during the Holocene as a result of landscape readjustment after ice retreat Ballantyne and Stone, ; Ballantyne et al.
A faster retreat of ice occurred from the Lotru valley towards the Zaanoaga Mare cirque. Boulders on the lateral moraine below the Zaanoaga Mare Lake were abandoned at Ice in this wide and shallow cirque would have received more solar radiation than the others cirques, speeding up the glacier retreat after separation from the Gaalcescu glacier.
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The subsequent thinning and narrowing of ice towards the middle of the cirque is indicated by the erosional paths of two former ice flow that are still visible today around the large whaleback located on the glacial threshold Figs. One of the ice flows followed the main Zaanoaga stream on the north side while the secondary flow was probably joined to the Gaalcescu glacier. During this time, a large amount of boulders were abandoned on top of the elongated deposits located in the middle of the cirque floor at Although the Gaalcescu cirque had a smaller accumulation area, snow drift from the upper surfaces would have contributed to a thicker glacier Gellatly et al.
Also sheltered by steep high walls, the Galcescu ice retreated slower than the glacier in the Zaanoaga Mare cirque located at similar altitudes. This is supported by the weighted mean 10Be exposure age of