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81-586: The Totes Gebirge surround Lake Altaussee in a horseshoe shape. The Loser (1873m above sea level ) lies to the north, with steep flanks that drop sharply to the lakeshore. To the east, the Trisselwand (1754m sea level) features a rock face that rises approximately 600 meters high. On the northeastern shore, the Seewiese marks the beginning of a trough valley that leads over the Hochklapfsattel to

162-555: A depth of 73m, while the water volume measures 72.7 million cubic meters. The lake can be reached via the Altausseerstraße L702. The lake is surrounded by a 7.4 km long circular hiking trail Uferpromenade. The hydrological catchment area of Lake Altaussee encompasses a total area of 54 km, entirely located within the Totes Gebirge . The lake's primary source of water is from karst springs located at

243-412: A documented history dating back to the 13th century. The fishing activities were under the authority of the sovereign lordship of Pflindsberg, and only a selected group of residents from the village of Fischerndorf had the privilege to engage in fishing. These individuals were obligated to pay fishing fees, which granted them the right to fish. The fishing operations were organized by guilds, as indicated by

324-405: A high percentage of CaMg(CO 3 ) 2 in which natural caves or solution tubes have formed. Both calcium and magnesium go into solution when dolomite rock is dissolved. The speleothem precipitation sequence is: calcite , Mg-calcite, aragonite , huntite and hydromagnesite . Hence, the most common speleothem (secondary deposit) in caves within dolomite rock karst , is calcium carbonate in

405-460: A high percentage of the mineral dolomite , CaMg(CO 3 ) 2 . It occurs widely, often in association with limestone and evaporites , though it is less abundant than limestone and rare in Cenozoic rock beds (beds less than about 66 million years in age). One of the first geologists to distinguish dolomite from limestone was Déodat Gratet de Dolomieu; a French mineralogist and geologist whom it

486-544: A high-calcium limestone, such as manufacture of sodium carbonate . Dolomite is used for production of magnesium chemicals, such as Epsom salt , and is used as a magnesium supplement. It is also used in the manufacture of refractory materials . As with limestone caves , natural caves and solution tubes typically form in dolomite rock as a result of the dissolution by weak carbonic acid. Caves can also, less commonly, form through dissolution of rock by sulfuric acid . Calcium carbonate speleothems (secondary deposits) in

567-405: A high-resolution multibeam echo sounder was used to create a detailed 3D model of the lake bottom in 2019. It shows, among other things, sediment formations of various kinds, large boulders, crater-shaped underwater springs, and around 100 standing tree trunks with heights of one to about fifteen meters distributed over the entire lake. In the summer of 2022, a 10-meter-tall white fir ( Abies alba )

648-407: A length of 2.6 km with a maximum width of 1 km, and a surface area of around 2.1 km. With an average depth of 35 m, the lake basin has steep slopes, except for the northeastern part, where the slope gradually decreases from approximately 40m depth, leading to a relatively large bottom zone with a maximum depth of 53m. The deepest point is a spring funnel near the north bank, which reaches

729-407: A low concentration of nutrients and is thus oligotrophic . Measurements in the years 2000 to 2006 showed an average phosphorus content of 6.7 μg/L. Due to the discharge of untreated wastewater, a eutrophication trend could be detected in the years 1963 to 1973 and the oxygen saturation above ground was already decreasing. In addition, bacteriological tests revealed the presence of salmonella . As

810-448: A microscope, dolomite rhombs are sometimes seen to replace oolites or skeletal particles of the original limestone. There is sometimes selective replacement of fossils, with the fossil remaining mostly calcite and the surrounding matrix composed of dolomite grains. Sometimes dolomite rhombs are seen cut across the fossil outline. However, some dolomite shows no textural indications that it was formed by replacement of limestone. Dolomite

891-566: A result, attempts to precipitate dolomite from seawater precipitate high-magnesium calcite instead. This substance, which has an excess of calcium over magnesium and lacks calcium-magnesium ordering, is sometimes called protodolomite . Raising the temperature makes it easier for magnesium to shed its hydration shell, and dolomite can be precipitated from seawater at temperatures in excess of 60 °C (140 °F). Protodolomite also rapidly converts to dolomite at temperatures of 250 °C (482 °F) or higher. The high temperatures necessary for

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972-399: A result, remediation measures began, which were completed in 1980 with the construction of a regional association sewage treatment plant with a third treatment stage in the municipal area of Bad Aussee . The hygienic situation of the bathing areas improved rapidly and the oligotrophic condition of the lake could be maintained. Several supply and disposal pipes run through the lake, connecting

1053-668: A temperature and precipitation distribution typically found in the Northern Limestone Alps: Cool and precipitation-rich summers, with a maximum of 16.2 °C and 220mm in July, respectively, and winters with low precipitation, with a minimum temperature of -2.2 °C in January. Precipitation shows a secondary maximum from December to January. Overall, the annual precipitation was 2041mm with an annual average temperature of 7.1 °C. The Schönberg group, located at

1134-408: A time of generally low sea levels. Times of high sea level also tend to be times of a greenhouse Earth , and it is possible that greenhouse conditions are the trigger for dolomite formation. Many dolomites show clear textural indications that they are secondary dolomites, formed by replacement of limestone. However, although much research has gone into understanding this process of dolomitization ,

1215-453: A very high ratio of calcium to magnesium. Dolomite is used for many of the same purposes as limestone, including as construction aggregate ; in agriculture to neutralize soil acidity and supply calcium and magnesium; as a source of carbon dioxide ; as dimension stone ; as a filler in fertilizers and other products; as a flux in metallurgy ; and in glass manufacturing . It cannot substitute for limestone in chemical processes that require

1296-513: A very small thickness of about two meters. The metalimnion lies at a depth of about five meters. The uniformly temperate hypolimnion begins at 10 meters. The strikingly high position of the metalimnion is due to the relatively wind-protected location and only moderate flooding of the lake. After the spring circulation, surface water temperatures gradually increase, reaching a long-term average of 16.3 °C in August. However, between 2000 and 2006,

1377-436: Is described as nonplanar or xenotopic dolomite. The latter likely forms by recrystallization of existing dolomite at elevated temperature (over 50 to 100 °C (122 to 212 °F)). The texture of dolomite often shows that it is secondary, formed by replacement of calcium by magnesium in limestone. The preservation of the original limestone texture can range from almost perfectly preserved to completely destroyed. Under

1458-591: Is filled by groundwater corresponding to the water level of Lake Altaussee. The Altaussee Traun , the lake's outlet, exits in the southwest at the Seeklause, where a bridge spans the outflow. It carves its path between the rock barrier of the Plattenkogel and the alluvial fan of the Augstbach, which acts as a natural dam for the lake. Originally, the Augstbach stream flowed into Lake Altaussee 250m north of

1539-699: Is freely accessible. Public bathing jetties are located at the Seeklausanger parking lot and at the Seepark in Altaussee. Lake Altaussee is also suitable for ice skating and curling, as it often freezes over completely in winter. During the Daffodil Festival at the end of May/beginning of June, which lasts several days, a boat parade takes place every third year on Lake Altaussee. Here, sculptures decorated with star daffodils are put on display. At

1620-462: Is largely composed of species such as Cyclops abyssorum , Eudiaptomus gracilis , Daphnia hyalina , and Eubosmina longispina . The potential natural vegetation on the riparian slopes is a spruce-fir-beech forest ( Aposerido-Fagetum ). However, centuries of prioritizing spruce as a fuel source for the salt flats have led to a significant depletion and displacement of fir and beech trees. Snow heath-red pine forests ( Erico-Pinetum ) can only be found in

1701-509: Is less soluble than limestone in weakly acidic groundwater , but it can still develop solution features ( karst ) over time. Dolomite rock can act as an oil and natural gas reservoir. Dolomite takes its name from the 18th-century French mineralogist Déodat Gratet de Dolomieu (1750–1801), who was one of the first to describe the mineral. The term dolomite refers to both the calcium-magnesium carbonate mineral and to sedimentary rock formed predominantly of this mineral. The term dolostone

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1782-444: Is named after. He recognized and described the distinct characteristics of dolomite in the late 18th century, differentiating it from limestone. Most dolomite was formed as a magnesium replacement of limestone or of lime mud before lithification . The geological process of conversion of calcite to dolomite is known as dolomitization and any intermediate product is known as dolomitic limestone . The "dolomite problem" refers to

1863-429: Is not native to the lake. The common pond mussel ( Anodonta anatina ) lives sporadically on the former alluvial cone of the Augstbach. The green jelly spherule ( Ophrydium versatile ) is also common. About 6 species of waterfowl have been recorded in the area. In addition to the common annual birds’ coot ( Fulica atra ), mute swan ( Cygnus olor ), mallard ( Anas platyrhynchos ), and tufted duck ( Aythya fuligula ),

1944-423: Is not seen to precipitate in the oceans. Likewise, geologists have not been successful at precipitating dolomite from seawater at normal temperatures and pressures in laboratory experiments. This is likely due to a very high activation energy for nucleating crystals of dolomite. The magnesium ion is a relatively small ion, and it acquires a tightly bound hydration shell when dissolved in water. In other words,

2025-543: Is subject to high rates of evaporation. This results in precipitation of gypsum and aragonite , raising the magnesium to calcium ratio of the remaining brine. The brine is also dense, so it sinks into the pore space of any underlying limestone ( seepage refluxion ), flushing out the existing pore fluid and causing dolomitization. The Permian Basin of North America has been put forward as an example of an environment in which this process took place. A variant of this model has been proposed for sabkha environments in which brine

2106-635: Is sucked up into the dolomitizing limestone by evaporation of capillary fluids, a process called evaporative pumping . Another model is the mixing-zone or Dorag model, in which meteoric water mixes with seawater already present in the pore space, increasing the chemical activity of magnesium relative to calcium and causing dolomitization. The formation of Pleistocene dolomite reefs in Jamaica has been attributed to this process. However, this model has been heavily criticized, with one 2004 review paper describing it bluntly as "a myth". A 2021 paper argued that

2187-408: Is the summit of Großer Priel , at 2,515 metres (8,251 ft). This Styria location article is a stub . You can help Misplaced Pages by expanding it . This Upper Austria location article is a stub . You can help Misplaced Pages by expanding it . Dolomite (rock) Dolomite (also known as dolomite rock , dolostone or dolomitic rock ) is a sedimentary carbonate rock that contains

2268-476: Is thermodynamically favorable, with a Gibbs free energy of about -2.2 kcal/mol. In theory, ordinary seawater contains sufficient dissolved magnesium to cause dolomitization. However, because of the very slow rate of diffusion of ions in solid mineral grains at ordinary temperatures, the process can occur only by simultaneous dissolution of calcite and crystallization of dolomite. This in turn requires that large volumes of magnesium-bearing fluids are flushed through

2349-550: Is usually a mixture of grains, micrite (very fine-grained carbonate mud) and sparry cement. The optical properties of calcite and mineral dolomite are difficult to distinguish, but calcite almost never crystallizes as regular rhombs, and calcite is stained by Alizarin Red S while dolomite grains are not. Dolomite rock consisting of well-formed grains with planar surfaces is described as planar or idiotopic dolomite, while dolomite consisting of poorly-formed grains with irregular surfaces

2430-409: Is widespread in its occurrences, though not as common as limestone. It is typically found in association with limestone or evaporite beds and is often interbedded with limestone. There is no consistent trend in its abundance with age, but most dolomite appears to have formed at high stands of sea level. Little dolomite is found in Cenozoic beds (beds less than 65 million years old), which has been

2511-823: The Dead Mountains , is a mountain range in Austria that forms part of the Northern Limestone Alps , lying between the Salzkammergut and the Ennstaler Alpen . The name Totes Gebirge is derived from the German words tot meaning "dead", referring to the apparent lack of vegetation, and Gebirge meaning "mountain range". The area is a large karst plateau with steep sides, and several mountain peaks above 2000 m. The highest point

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2592-694: The Triassic and Jurassic periods. Within the western part of the Totes Gebirge, lies the Schönberg group, which is geologically distinct from the Priel group due to a deep incursion furrow. The Wildensee line is a geological structure that stretches from Lake Altaussee, traverses the Hochklapfsattel, extends to Wildensandee Lake, and continues over the Rinnerboden to Offensee Lake. The base of

2673-407: The field by their softness (mineral dolomite has a Mohs hardness of 4 or less, well below common silicate minerals) and because dolomite bubbles feebly when a drop of dilute hydrochloric acid is dropped on it. This distinguishes dolomite from limestone, which is also soft but reacts vigorously with dilute hydrochloric acid. Dolomite usually weathers to a characteristic dull yellow-brown color due to

2754-461: The great crested grebe ( Podiceps cristatus ) is also among the breeding birds. The great egret ( Ardea alba ) also lives at the lake. With its largely undeveloped shores with nearby marshes and wooded steep slopes, the lake provides habitats for many animal and plant species and the area has been under nature protection since 1959. The Altaussee Nature Reserve (NSG-a03) spans 242 hectares and extends to an altitude of 1600m above sea level. In 2006,

2835-698: The 19th century, Altaussee developed into a "home of writers". Raoul Auernheimer , in his autobiography " Das Wirtshaus zur verlorenen Zeit ", compares the lake to an inkwell into which “the poets sitting around in circles dipped their quills”. The influence of the lake is documented in the Altaussee Literature Museum. The lake and the hunting lodge Seewiese were filming locations for the James Bond film Spectre in 2015. Totes Gebirge The Totes Gebirge , also known in English as

2916-614: The Loser mountain is composed predominantly of Dachstein limestone , while the Plattenkogel showcases Pedata limestone or dolomite formations, both originating from the Triassic period. The Trisselwand and Tressenstein areas exhibit the presence of Oberalmer Formation and Tressensteinkalk, which formed during the Jurassic period. Scattered around the lake, one can observe remnants of terminal and lateral moraines , offering glimpses into

2997-546: The Madlmaier landing stage in Altaussee and the Seewiese landing stage on the northeast shore. On May 7, 2011, the Altaussee, Austria's first solar-electric powered catamaran , began operating on the lake. The boat has room for 80 passengers. Since 2018, the company has also been offering flatboat trips including skippers. Combustion engines are prohibited on ships and boats in Lake Altaussee, as well as on all lakes in

3078-575: The Seeklause using ashlars began in 1781. Additionally, an external rake was built around 1300 to gather the floated wood. However, after the brewing operation in Aussee market in 1867, the rake fell into disuse. The final wood drifting event on the Altaussee Traun occurred in 1882. Presumably, the Klause was destroyed during a flood in 1899. Subsequent to the catastrophic floods of 1897 and 1899,

3159-524: The Seewiese area. This event occurs due to the presence of two cave entrances situated at different elevations. During this spectacle, vast amounts of water accumulate within a cave in the middle section of the Loserwand. The resulting overpressure causes a large jet of water to shoot out of the cave portal of the Liager hole in a high arc . The process, with some interruptions, only takes about an hour, and

3240-740: The Totes Gebirge European Protected Area with Lake Altaussee European Protected Area No. 35 was designated under the Habitats and Birds Directives as part of the Natura 2000 network. The Walter Munk Foundation for the Oceans supports research projects in the field of limnology, ecology, and underwater archaeology at Lake Altaussee. Together with the University of Natural Resources and Applied Life Sciences Vienna ,

3321-420: The basin once again, giving it its current form. Simultaneously, as the over-deepened basin was being freed from the ice, a lake began to form at the edge of the ice body. This phase, marked by the presence of a high debris formation around Lake Altaussee's basin, indicates the interaction between the ice body and the lake basin. As the ice eventually disappeared entirely, the alluvial cone adjusted to accommodate

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3402-543: The bridge during the spawning season. Additionally, there is a spawning sanctuary (Laichschonstätte) located at the Lechthütte on the southeast bank. The char in Lake Altaussee spawn from October to November on gravel banks that are free of silt, typically at a depth of around 20 meters. To support the char population, a portion of the fish is captured using nets during what is known as "leaching batches." The eggs are then stripped and fertilized to cultivate young fish. During

3483-534: The bulk quantities can reach 3000 L/s. The waterfall turns into a torrent in the area of the wall, which tumbles down to the lake and, together with the strong underground inflow, causes the lake level to rise by up to 60 cm within just 12 hours. Lake Altaussee is a component of the Northern Limestone Alps , which lies on the southwestern edge of the Totengebirge cover (Tirolic period), characterized by its abundance of Mesozoic limestones and dolomites from

3564-459: The edge of the Totes Gebirge , benefits from frequent cloud accumulation, resulting in above-average precipitation in that area. A comparison with Bad Mitterndorf , situated on the southern side of the Totes Gebirge and approximately 12 km away, highlights the barrier effect of the Totes Gebirge at a similar altitude. Bad Mitterndorf receives annual precipitation of 1222mm at an elevation of 803m above sea level. In terms of snow cover duration,

3645-531: The formation of dolomite helps explain the rarity of Cenozoic dolomites, since Cenozoic seawater temperatures seldom exceeded 40 °C. It is possible that microorganisms are capable of precipitating primary dolomite. This was first demonstrated in samples collected at Lagoa Vermelha , Brazil in association with sulfate-reducing bacteria ( Desulfovibrio ), leading to the hypothesis that sulfate ion inhibits dolomite nucleation. Later laboratory experiments suggest bacteria can precipitate dolomite independently of

3726-484: The forms of stalactites , stalagmites , flowstone etc., can also form in caves within dolomite rock. “Dolomite is a common rock type, but a relatively uncommon mineral in speleothems”. Both the 'Union Internationale de Spéléologie' (UIS) and the American 'National Speleological Society' (NSS), extensively use in their publications, the terms "dolomite" or "dolomite rock" when referring to the natural bedrock containing

3807-417: The genus Cyclotella standing out. In particular, Cyclotella Styria is a unique species found exclusively in Lake Altaussee and Lake Grundlsee . The zooplankton community, on the other hand, exhibits significantly higher biomass. Among the rotifers , the species Kellicottia longispina , Keratella cochlearis , and Keratella hiemalis were frequently observed. The crustacean plankton in Lake Altaussee

3888-404: The greater temperatures characterizing deeper burial, if a mechanism exists to flush magnesium-bearing fluids through the beds. Mineral dolomite has a 12% to 13% smaller volume than calcite per alkali cation. Thus dolomitization likely increases porosity and contributes to the sugary texture of dolomite. Dolomite is supersaturated in normal seawater by a factor of greater than ten, but dolomite

3969-476: The horizon of the Dietrichskogel. In the past, the fisherman's cross was a freestanding structure easily visible from all directions. However, it is now obscured by tall trees. The perch ( Perca fluviatilis ) was not originally native to the lake but entered the water body at the end of the 1980s for yet unexplained reasons. As a foreign fish species, it changed the aquatic ecosystem and caused damage to

4050-574: The individual dolomite mineral grains, rather than being arranged at random, as they are in high-magnesium calcite grains. In natural dolomite, magnesium is typically between 44 and 50 percent of total magnesium plus calcium, indicating some substitution of calcium into the magnesium layers. A small amount of ferrous iron typically substitutes for magnesium, particularly in more ancient dolomites. Carbonate rock tends to be either almost all calcite or almost all dolomite, with intermediate compositions being quite uncommon. Dolomite outcrops are recognized in

4131-405: The inner Salzkammergut region. However, there are some exceptions to this rule, including professional fishing, liner shipping, and vehicles used by rescue and fire departments. Lake Altaussee is a popular destination for excursions because of its beautiful location. In Altaussee exists a distinctive tourist infrastructure with accommodation and catering establishments. The hunting lodge Seewiese on

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4212-493: The lake is still conducted professionally to this day. Lake Altaussee is renowned for its large char and trout populations, with Arctic char accounting for approximately 90% of the total catch. The shallow and flowing water on the lake side of the Seeklause serves as a crucial spawning area for lake trout, which spawn from October to December. To prevent the fish from migrating into the Traun River, grids are installed under

4293-520: The lake outlet. However, due to the issue of saline water from the nearby salt mine repeatedly reaching the lake through this stream, the stream bed was artificially relocated before 1530. Since then, the Augstbach has been redirected to flow westward, past Lake Altaussee, and into the Traun River approximately 150m downstream from the lake outlet. After heavy and prolonged rainfalls, a hydrological karst phenomenon known as "the Liagern" can be witnessed in

4374-438: The lake's bottom, which receive underground flow from debris and rock crevices. These springs have an average total discharge of 3750 L/s. Additionally, there are a few small spring outlets along the shores with a combined discharge of approximately 20 L/s. Lake Altaussee demonstrates typical fluctuations in discharge commonly associated with karst springs. In the northeast, there is a small dead ice hole called Lake Osterseen, which

4455-437: The magnesium ion is surrounded by a clump of water molecules that are strongly attracted to its positive charge. Calcium is a larger ion and this reduces the strength of binding of its hydration shell, so it is much easier for a calcium ion than a magnesium ion to shed its hydration shell and bind to a growing crystal. It is also more difficult to nucleate a seed crystal of ordered dolomite than disordered high-magnesium calcite. As

4536-453: The mean August temperature was higher at 18.4 °C, nearly 2 °C above the long-term average. The highest recorded water temperature in the lake was 21.8 °C during the summer of 2003. At depths below 15 meters, temperatures average around 4.6 °C. Throughout the summer stagnation phase, the hypolimnion warms up by an average of only 0.3 °C. The lake is typically covered by ice for an average of 57 days each year. The lake has

4617-451: The mechanism of dolomitization, the tendency of carbonate rock to be either almost all calcite or almost all dolomite suggests that, once the process is started, it completes rapidly. The process likely occurs at shallow depths of burial, under 100 meters (330 ft), where there is an inexhaustible supply of magnesium-rich seawater and the original limestone is more likely to be porous. On the other hand, dolomitization can proceed rapidly at

4698-492: The mixing zone serves as domain of intense microbial activity which promotes dolomitization. A third model postulates that normal seawater is the dolomitizing fluid, and the necessary large volumes are flushed through the dolomitizing limestone through tidal pumping. Dolomite formation at Sugarloaf Key , Florida, may be an example of this process. A similar process might occur during rises in sea level, as large volumes of water move through limestone platform rock. Regardless of

4779-399: The name Fischerndorf. The allocation of fishing rights was based on the size of the land owned by the entitled farmers. In Altaussee, fishing rights are passed down through generations and are considered hereditary. The Austrian Federal Forests hold the lake, but the rights of the fishermen are registered in the land register and have been owned by the local families for generations. Fishing in

4860-506: The nearby town of Bad Aussee , located 3 km away, experiences approximately 126 days of winter snow cover. Lake Altaussee is classified as a dimictic lake . In spring after the ice melts, the water body mixes and brings oxygen-rich water into the depths. In the summer half-year, a distinct thermocline forms, and only the surface layer warms up, in autumn mixing occurs again, followed by ice formation. Strict stratification conditions are present in Lake Altaussee. The epilimnion has only

4941-532: The northeast shore was originally owned by the Hohenlohe-Schillingsfürst family and is now run as an inn. It contains a small natural history museum on the second floor, which focuses on Lake Altaussee and the numerous fossils found in the region. To the south of the Seewiese, an inn dating from the 1900s was purchased by Dietrich Mateschitz and rebuilt in local style in May 2018. Most of the shore

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5022-410: The outlet of Lake Altaussee, like other lakes in the inner Salzkammergut, there existed a hermitage specifically used for wood drifting. With relatively modest means, this location allowed for the storage of large quantities of water. The first mention of this hermitage dates back to the forest survey of 1561. In 1633, a new building was constructed, entirely made of wood at the time. The reconstruction of

5103-521: The plateau of the Totes Gebirge . To the south, the Tressenstein (1201m above sea level) follows, while the village of Altaussee in the hilly area of the Aussee Basin is situated to the west. The shores are rocky and steep, particularly in the north, while in other areas, they are partly pebbly, flat and largely undeveloped. The lake stretches from west-southwest to east-northeast, covering

5184-475: The population of minnows and Arctic char, on whose spawn it feeds. To restore the balance, attempts are being made to reduce the population of the perch. One method involves placing submerged spruce branches, where the perch lay their eggs, and then removing the branches to destroy the fish eggs. The company Stern Schifffahrt GmbH, based in Gmunden , operates shipping on Lake Altaussee. Boats run regularly between

5265-427: The pore space in the dolomitizing limestone. Several processes have been proposed for dolomitization. The hypersaline model (also known as the evaporative reflux model ) is based on the observation that dolomite is very commonly found in association with limestone and evaporites , with the limestone often interbedded with the dolomite. According to this model, dolomitization takes place in a closed basin where seawater

5346-511: The presence of ferrous iron. This is released and oxidized as the dolomite weathers. Dolomite is usually granular in appearance, with a texture resembling grains of sugar . Under the microscope, thin sections of dolomite usually show individual grains that are well-shaped rhombs , with considerable pore space. As a result, subsurface dolomite is generally more porous than subsurface limestone and makes up 80% of carbonate rock petroleum reservoirs . This texture contrasts with limestone, which

5427-470: The present lake level. Originally, the lake area was likely more extensive, stretching over the Seewiese and reaching the Osterseen . Over the course of the post-glacial period, the lake basin constantly changed its shape as a result of silting up. It is expected that, over tens of thousands of years, the lake basin will eventually vanish once again, further transforming the landscape. The climate data show

5508-401: The process remains poorly understood. There are also fine-grained dolomites showing no textural indications that they formed by replacement, and it is uncertain whether they formed by replacement of limestone that left no textural traces or are true primary dolomites. This dolomite problem was first recognized over two centuries ago but is still not fully resolved. The dolomitization reaction

5589-456: The question of whether this can lead to precipitation of dolomite. Dolomitization can sometimes be reversed, and a dolomite bed converted back to limestone. This is indicated by a texture of pseudomorphs of mineral dolomite that have been replaced with calcite. Dedolomitized limestone is typically associated with gypsum or oxidized pyrite , and dedolomitization is thought to occur at very shallow depths through infiltration of surface water with

5670-531: The region's glacial history and the shaping of its surrounding landscape. During the ice ages , the Altaussee glacier flowed from the Totes Gebirge plateau, flowing over the Aussee basin and reaching the Traun glacier near Bad Goisern . The glacier's movement was instrumental in sculpting the valley's over-deepened basin of Lake Altaussee. About 16,000 years ago, a powerful readvance of the glacier occurred and filled

5751-525: The remaining traces of the rake were eliminated as part of the shore reinforcement measures. In the last days of the Second World War , a truck was sunk on the north bank. Today, this consists only of fragments scattered over an area of about 20 × 40 m. As the nobility began to settle in Ausseerland, Altaussee also attracted more and more writers, painters, and musicians. From the middle of

5832-407: The rest areas at the Seewiese and the beach café located on the southern shore to the sewage system. Due to the low phytoplankton concentration and low algae growth, the average summer visibility depth is 8.9 meters. According to chlorophyll studies, algae growth in Lake Altaussee is relatively low. Cryptophyceae and diatoms are the principal phytoplankton community components, with species from

5913-412: The rockiest, driest regions. In the Seewiese, a treeless area created by mowing and grazing , there are tall perennials such as meadowsweet ( Filipendula ulmaria ), ring thistle ( Carduus personata ), and monkshood ( Aconitum napellus ). In the meadow around the hunting lodge, many star daffodils ( Narcissus radiiflorus ) bloom in the second half of May. On the shore edge of the lake meadow grows

5994-596: The shallower shore areas. Grass pondweed ( Potamogeton gramineus ) grows only locally in the reed stand ( Phragmites australis ) on the north bank and marsh pond thread ( Zannichellia palustris ) on the bank near the church. Dense stonewort algae lawns on the former alluvial cone of the Augstbach are conspicuous. The fish population of Lake Altaussee is composed of the following species: burbot ( Lota lota ), chub ( Squalius cephalus ), minnow ( Phoxinus phoxinus ), perch ( Perca fluviatilis ), lake Trout ( Salmo trutta ) and arctic Char ( Salvelinus alpinus ). The perch

6075-400: The sulfate concentration. With time other pathways of interaction between microbial activity and dolomite formation have been added to the discord regarding their role in modulation and generation of polysaccharides , manganese and zinc within the porewater. Meanwhile, a contrary view held by other researchers is that microorganisms precipitate only high-magnesium calcite but leave open

6156-493: The summer, these young fish are released back into the lake. The fishermen's cross, located on the western shore, used to serve as a guide to locate the spawning grounds and the best fishing spots for Arctic char. Fishermen would navigate with a flatboat to a specific point where the alignment of the Granzling, the tip of the flatboat, the fisherman's cross, and the Dietrichskogel formed a line. The cross needed to be positioned on

6237-427: The vast worldwide depositions of dolomite in the past geologic record in contrast to the limited amounts of dolomite formed in modern times. Recent research has revealed sulfate-reducing bacteria living in anoxic conditions precipitate dolomite which indicates that some past dolomite deposits may be due to microbial activity. Dolomite is resistant to erosion and can either contain bedded layers or be unbedded. It

6318-801: The very rare shore buttercup ( Ranunculus reptans ). It is found in Austria and on the shores of Lake Constance . On the very dry, steep, and south-exposed slopes of the “Bumpy Stone Walls” in the shore area grows the mountain laserwort ( Laserpitium siler ), the only host plant of the mountain cumin summer work ( Orobanche laserpitii-sileris) , which is highly uncommon in Austria. This full parasite reaches flowering there only in wet years. In Lake Altaussee, mirror pondweed ( Potamogeton lucens ), alpine pondweed ( Potamogeton alpinus ), crested pondweed ( Stuckenia pectinate ), Berchtold's dwarf pondweed ( Potamogeton berchtoldii ) and hairy-leaved water crowfoot ( Ranunculus trichophyllus ) occur in larger stands in places in

6399-550: Was introduced in 1948 to avoid confusion between the two. However, the usage of the term dolostone is controversial, because the name dolomite was first applied to the rock during the late 18th century and thus has technical precedence. The use of the term dolostone was not recommended by the Glossary of Geology published by the American Geological Institute . In old USGS publications, dolomite

6480-429: Was recovered from the lake. By combining dendrochronology and radiocarbon methods, the age could be accurately determined. The tree has 247 annual rings and died in 859 AD. The rootstock of the fir can be visited on the north bank. How the approximately 100 tree trunks got into the lake - for example, through a tectonic event, or whether they grew in the site - require further investigation. Lake fishing in Altaussee has

6561-440: Was referred to as magnesian limestone , a term now reserved for magnesium -deficient dolomites or magnesium-rich limestones. Dolomite rock is defined as sedimentary carbonate rock composed of more than 50% mineral dolomite . Dolomite is characterized by its nearly ideal 1:1 stoichiometric ratio of magnesium to calcium. It is distinct from high-magnesium limestone in that the magnesium and calcium form ordered layers within

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