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88-579: The escarpment is a UNESCO World Biosphere Reserve . The reserve has the oldest forest ecosystem and trees in eastern North America. The escarpment is not a fault line but the result of unequal erosion . It is composed of an outcrop belt of the Lockport Formation of Silurian age, and is similar to the Onondaga Formation , which runs in a parallel outcrop belt just to the south, through western New York and southern Ontario . The escarpment

176-710: A non-governmental organization in the service of international educational development since December 1925 and joined UNESCO in 1969, after having established a joint commission in 1952. After the signing of the Atlantic Charter and the Declaration of the United Nations , the Conference of Allied Ministers of Education (CAME) began meetings in London which continued from 16 November 1942 to 5 December 1945. On 30 October 1943,

264-467: A Commission to study the feasibility of having nations freely share cultural, educational and scientific achievements. This new body, the International Committee on Intellectual Cooperation (ICIC), was created in 1922 and counted such figures as Henri Bergson , Albert Einstein , Marie Curie , Robert A. Millikan , and Gonzague de Reynold among its members (being thus a small commission of

352-418: A French mineralogist and geologist whom it 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

440-482: A Preparatory Commission was established. The Preparatory Commission operated between 16 November 1945, and 4 November 1946 — the date when UNESCO's Constitution came into force with the deposit of the twentieth ratification by a member state. The first General Conference took place from 19 November to 10 December 1946, and elected Julian Huxley to Director-General. United States Army colonel, university president and civil rights advocate Blake R. Van Leer joined as

528-656: A United Nations Conference for the establishment of an educational and cultural organization (ECO/CONF) was convened in London from 1 to 16 November 1945 with 44 governments represented. The idea of UNESCO was largely developed by Rab Butler , the Minister of Education for the United Kingdom, who had a great deal of influence in its development. At the ECO/CONF, the Constitution of UNESCO was introduced and signed by 37 countries, and

616-638: A biennium, as well as links to relevant programmatic and financial documents. These two distinct sets of information are published on the IATI registry, respectively based on the IATI Activity Standard and the IATI Organization Standard. There have been proposals to establish two new UNESCO lists. The first proposed list will focus on movable cultural heritage such as artifacts, paintings, and biofacts. The list may include cultural objects, such as

704-724: A concern for the lake's ecosystem. In southern Ontario, the Bruce Trail runs the length of the escarpment from Queenston on the Niagara River to Tobermory on the Bruce Peninsula. Highway 401 , Canada's busiest, also crosses the Niagara Escarpment, beginning its long descent through rolling hills, farmland, and towns west of Milton. Rock exposed on the face of the escarpment can be seen along Highway 26 from Owen Sound eastwards towards Meaford, Ontario . Hamilton, Ontario

792-493: A declaration of anthropologists (among them was Claude Lévi-Strauss ) and other scientists in 1950 and concluding with the 1978 Declaration on Race and Racial Prejudice . In 1955, the Republic of South Africa withdrew from UNESCO saying that some of the organization's publications amounted to "interference" in the country's "racial problems". It rejoined the organization in 1994 under the leadership of Nelson Mandela . One of

880-434: 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 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

968-536: A full member. As a result, the United States withdrew its funding, which had accounted for about 22% of UNESCO's budget. Israel also reacted to Palestine's admittance to UNESCO by freezing Israeli payments to UNESCO and imposing sanctions on the Palestinian Authority , stating that Palestine's admittance would be detrimental "to potential peace talks". Two years after stopping payment of its dues to UNESCO,

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1056-543: A global movement in 1990 to provide basic education for all children, youths and adults. In 2000, World Education Forum in Dakar , Senegal, led member governments to commit for achieving basic education for all in 2015. The World Declaration on Higher Education was adopted by UNESCO's World Conference on Higher Education on 9 October 1998, with the aim of setting global standards on the ideals and accessibility of higher education . UNESCO's early activities in culture included

1144-405: 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

1232-544: 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

1320-403: A marine environment. In Michigan, behind (south of) the escarpment, the cuesta capstone slopes gently to form a wide basin , the floor of an Ordovician -Silurian-age tropical sea. (The escarpment is essentially the remnant shoreline of that sea.) There the constant deposition of minute shells and fragments of biologically-generated calcium carbonate , mixed with sediment washed in by erosion of

1408-613: A member as well. The Constitution was amended in November 1954 when the General Conference resolved that members of the executive board would be representatives of the governments of the States of which they are nationals and would not, as before, act in their personal capacity. This change in governance distinguished UNESCO from its predecessor, the ICIC, in how member states would work together in

1496-444: A platform for the dialogue between cultures and provide a forum for international debate". Since March 2006 it has been available free online, with limited printed issues. Its articles express the opinions of the authors which are not necessarily the opinions of UNESCO. There was a hiatus in publishing between 2012 and 2017. In 1950, UNESCO initiated the quarterly review Impact of Science on Society (also known as Impact ) to discuss

1584-405: A process of differential erosion of these rocks of different hardnesses. Through time the soft rocks weather away or erode by the action of streams. The gradual removal of the soft rocks undercuts the resistant caprock, leaving a cliff or escarpment. The erosional process is most readily seen at Niagara Falls , where the river has quickened the process. It can also be seen at the three waterfalls of

1672-566: 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

1760-453: 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

1848-461: Is a sedimentary carbonate rock that contains 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;

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1936-611: Is a prominent Wisconsin feature in Dodge County, southwest of Fond du Lac, Wisconsin; it is known there as "The Ledge" and is in Ledge County Park between Horicon and Mayville, Wisconsin. Some local organizations take their name from it, including The Ledgers, the sports teams at St. Mary's Springs Academy , which is perched on the side of the escarpment. Many resorts and ski areas in Ontario, Michigan, Wisconsin, and New York are along

2024-578: Is an eastern white cedar from 688 A.D. The oldest known tree in Wisconsin, a 1,300 year-old eastern white cedar, was found in Brown County. United Nations Educational, Scientific and Cultural Organization The United Nations Educational, Scientific, and Cultural Organization ( UNESCO ; pronounced / j uː ˈ n ɛ s k oʊ / ) is a specialized agency of the United Nations (UN) with

2112-490: Is another example of an early major UNESCO project in the field of natural sciences. In 1968, UNESCO organized the first intergovernmental conference aimed at reconciling the environment and development, a problem that continues to be addressed in the field of sustainable development . The main outcome of the 1968 conference was the creation of UNESCO's Man and the Biosphere Programme . UNESCO has been credited with

2200-467: 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 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

2288-450: Is corrupted and manipulated by Israel's enemies... we are not going to be a member of an organisation that deliberately acts against us". 2023 saw Russia excluded from the executive committee for the first time, after failing to get sufficient votes. The United States stated its intent to rejoin UNESCO in 2023, 5 years after leaving, and to pay its $ 600 million in back dues. The United States

2376-461: Is governed by the General Conference composed of member states and associate members, which meets biannually to set the agency's programs and budget. It also elects members of the executive board, which manages UNESCO's work, and appoints every four years a Director-General, who serves as UNESCO's chief administrator. UNESCO and its mandate for international cooperation can be traced back to a League of Nations resolution on 21 September 1921, to elect

2464-413: Is known as dolomitic limestone . The "dolomite problem" refers to 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

2552-626: 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 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 ,

2640-423: 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,

2728-499: Is on the escarpment in such a way that the north end of the city is below and the south part above. Commonly referred to as "The Mountain" by its residents, many roads or "mountain accesses" join the urban core below with the suburban expansion above. From 1892 to 1936, the Hamilton Incline Railway transported people up and down "The Mountain." High Cliff State Park in Wisconsin shows how modern and prehistoric humans used

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2816-419: Is resistant to erosion and can either contain bedded layers or be unbedded. It 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

2904-416: 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 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

2992-538: 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 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

3080-543: 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

3168-630: 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

3256-534: Is the most prominent of several escarpments formed in the bedrock of the Great Lakes Basin . From its easternmost point just south of Lake Ontario, the escarpment shapes in part the individual basins and landforms of Lake Ontario , Lake Huron , and Lake Michigan . In Rochester, New York , the Genesee River flows through the city in three waterfalls over the scarp face. The escarpment thence runs westward to

3344-476: 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

3432-801: The Acropolis of Athens (Greece). The organization's work on heritage led to the adoption, in 1972, of the Convention concerning the Protection of the World Cultural and Natural Heritage. In 1976, the World Heritage Committee was established and the first sites were included on the World Heritage List in 1978. Since then important legal instruments on cultural heritage and diversity have been adopted by UNESCO member states in 2003 (Convention for

3520-751: The International Campaign to Save the Monuments of Nubia , launched in 1960. The purpose of the campaign was to move the Great Temple of Abu Simbel to keep it from being swamped by the Nile after the construction of the Aswan Dam . During the 20-year campaign, 22 monuments and architectural complexes were relocated. This was the first and largest in a series of campaigns including Mohenjo-daro (Pakistan), Fes (Morocco), Kathmandu (Nepal), Borobudur (Indonesia) and

3608-951: The Jōmon Venus of Japan, the Mona Lisa of France, the Gebel el-Arak Knife of Egypt , The Ninth Wave of Russia, the Seated Woman of Çatalhöyük of Turkey, the David (Michelangelo) of Italy, the Mathura Herakles of India, the Manunggul Jar of the Philippines, the Crown of Baekje of South Korea, The Hay Wain of the United Kingdom and the Benin Bronzes of Nigeria. The second proposed list will focus on

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3696-428: The United Nations member states (except Israel and Liechtenstein ), as well as Cook Islands , Niue and Palestine . The United States and Israel left UNESCO on 31 December 2018, but the United States rejoined in 2023. As of June 2023 , there have been 11 Directors-General of UNESCO since its inception – nine men and two women. The 11 Directors-General of UNESCO have come from six regions within

3784-819: The Directors-General of UNESCO since its establishment in 1946 is as follows: This is the list of the sessions of the UNESCO General Conference held since 1946: Ahmet Altay Cengizer Biennial elections are held, with 58 elected representatives holding office for four years. [REDACTED]   Finland [REDACTED]   Portugal [REDACTED]   Turkey [REDACTED]   Albania [REDACTED]   Belarus [REDACTED]   Bulgaria [REDACTED]   Cuba [REDACTED]   Grenada [REDACTED]   Jamaica [REDACTED]   Saint Lucia [REDACTED]   Saint Vincent and

3872-520: The Genesee River at Rochester (additional resistant rock layers make more than one escarpment in some places). Also, in some places thick glacial deposits, such as the Oak Ridges Moraine , conceal the Niagara Escarpment, such as north of Georgetown, Ontario , where it actually continues under glacial till and reappears farther north. The dolomite cap was laid down as sediment on the floor of

3960-1857: The Grenadines [REDACTED]   Venezuela [REDACTED]   Bangladesh [REDACTED]   China [REDACTED]   India [REDACTED]   Indonesia [REDACTED]   Japan [REDACTED]   Philippines [REDACTED]   Burundi [REDACTED]   Equatorial Guinea [REDACTED]   Ethiopia [REDACTED]   Madagascar [REDACTED]   Zambia [REDACTED]   Zimbabwe [REDACTED]   Egypt [REDACTED]   Jordan [REDACTED]   Morocco [REDACTED]   France [REDACTED]   Germany [REDACTED]   Italy [REDACTED]   Netherlands [REDACTED]   Spain [REDACTED]    Switzerland [REDACTED]   Hungary [REDACTED]   Poland [REDACTED]   Russia [REDACTED]   Serbia [REDACTED]   Argentina [REDACTED]   Brazil [REDACTED]   Dominican Republic [REDACTED]   Uruguay [REDACTED]   Afghanistan [REDACTED]   Kyrgyzstan [REDACTED]   Philippines [REDACTED]   Pakistan [REDACTED]   South Korea [REDACTED]   Thailand [REDACTED]   Benin [REDACTED]   Congo [REDACTED]   Guinea [REDACTED]   Ghana [REDACTED]   Kenya [REDACTED]   Namibia [REDACTED]   Senegal [REDACTED]   Togo [REDACTED]   Saudi Arabia [REDACTED]   UAE [REDACTED]   Tunisia Dolomite (rock) Dolomite (also known as dolomite rock , dolostone or dolomitic rock )

4048-622: The League of Nations essentially centred on Western Europe ). The International Institute for Intellectual Cooperation (IIIC) was then created in Paris in September 1924, to act as the executing agency for the ICIC. However, the onset of World War II largely interrupted the work of these predecessor organizations. As for private initiatives, the International Bureau of Education (IBE) began to work as

4136-573: The Niagara River, forming a deep gorge north of Niagara Falls , which itself cascades over the scarp face. In southern Ontario , it spans the Niagara Peninsula , closely following the Lake Ontario shore through the cities of St. Catharines and Hamilton , where it takes a sharp turn north in the town of Milton toward Georgian Bay . It then follows the Georgian Bay shore northwestwards to form

4224-791: The Safeguarding of the Intangible Cultural Heritage ) and 2005 ( Convention on the Protection and Promotion of the Diversity of Cultural Expressions ). An intergovernmental meeting of UNESCO in Paris in December 1951 led to the creation of the European Council for Nuclear Research , which was responsible for establishing the European Organization for Nuclear Research (CERN) later on, in 1954. Arid Zone programming, 1948–1966,

4312-537: The United States and Israel lost UNESCO voting rights in 2013 without losing the right to be elected; thus, the United States was elected as a member of the executive board for the period 2016–19. In 2019, Israel left UNESCO after 69 years of membership, with Israel's ambassador to the UN Danny Danon writing: "UNESCO is the body that continually rewrites history, including by erasing the Jewish connection to Jerusalem... it

4400-456: The aim of promoting world peace and security through international cooperation in education, arts, sciences and culture. It has 194 member states and 12 associate members, as well as partners in the non-governmental , intergovernmental and private sector . Headquartered in Paris , France, UNESCO has 53 regional field offices and 199 national commissions. UNESCO was founded in 1945 as

4488-715: The commission, the Nobel Peace Prize laureate Seán MacBride ). The same year, UNESCO created the International Programme for the Development of Communication (IPDC), a multilateral forum designed to promote media development in developing countries. In 1993, UNESCO's General Conference endorsed the Windhoek Declaration on media independence and pluralism, which led the UN General Assembly to declare

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4576-525: The date of its adoption, 3 May, as World Press Freedom Day . Since 1997, UNESCO has awarded the UNESCO / Guillermo Cano World Press Freedom Prize every 3 May. UNESCO admitted Palestine as a member in 2011. Laws passed in the United States after Palestine applied for UNESCO and WHO membership in April 1989 mean that the United States cannot contribute financially to any UN organization that accepts Palestine as

4664-481: The diffusion of national science bureaucracies. In the field of communication, the "free flow of ideas by word and image" has been in UNESCO's constitution since it was established, following the experience of the Second World War when control of information was a factor in indoctrinating populations for aggression. In the years immediately following World War II, efforts were concentrated on reconstruction and on

4752-553: The early work of UNESCO in the education field was a pilot project on fundamental education in the Marbial Valley, Haiti, which was launched in 1947. Following this project one of expert missions to other countries, included a 1949 mission to Afghanistan. UNESCO recommended in 1948 that Member countries should make free primary education compulsory and universal. The World Conference on Education for All , in Jomtien , Thailand, started

4840-438: The escarpment for not only cultural reasons, but economic gains, as well. A number of different animal and geometric effigy mounds and the remains of an early 20th-century limestone quarry and kiln are within the park. The relief and exposed edge are used by several wind farms stretching from Pipe to Brownsville in Wisconsin. Wind speeds average 18 mph (about 29 km/h) along this stretch. The Niagara Escarpment

4928-400: The escarpment. Niagara County, New York , near the eastern end of the escarpment, is the site of the 18,000 acres (7,284 ha) Niagara Escarpment AVA ( American Viticultural Area ). Wines produced in this region include traditional grape varieties such as Merlot , Cabernet Franc , Cabernet Sauvignon , Chardonnay , and Riesling , and fruit wines . Ontario's Niagara Peninsula is

5016-531: 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

5104-479: 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

5192-404: 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

5280-526: The identification of needs for means of mass communication around the world. UNESCO started organizing training and education for journalists in the 1950s. In response to calls for a " New World Information and Communication Order " in the late 1970s, UNESCO established the International Commission for the Study of Communication Problems, which produced the 1980 MacBride report (named after the chair of

5368-529: The influence of science on society. The journal ceased publication in 1992. UNESCO also published Museum International Quarterly from the year 1948. UNESCO has official relations with 322 international non-governmental organizations (NGOs). Most of these are what UNESCO calls "operational"; a select few are "formal". The highest form of affiliation to UNESCO is "formal associate", and the 22 NGOs with formal associate (ASC) relations occupying offices at UNESCO are: The institutes are specialized departments of

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5456-437: 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

5544-461: 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 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

5632-451: 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

5720-571: 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 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

5808-427: 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 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

5896-492: 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

5984-734: The necessity for an international organization was expressed in the Moscow Declaration, agreed upon by China , the United Kingdom, the United States and the USSR. This was followed by the Dumbarton Oaks Conference proposals of 9 October 1944. Upon the proposal of CAME and in accordance with the recommendations of the United Nations Conference on International Organization (UNCIO), held in San Francisco from April to June 1945,

6072-582: The organization that support UNESCO's programme, providing specialized support for cluster and national offices. UNESCO awards 26 prizes in education, natural sciences, social and human sciences, culture, communication and information as well as peace: International Days observed at UNESCO are provided in the table below: As of July 2023 , UNESCO has 194 member states and 12 associate members. Some members are not independent states and some members have additional National Organizing Committees from some of their dependent territories . UNESCO state parties are

6160-445: The organization's fields of competence. As member states worked together over time to realize UNESCO's mandate, political and historical factors have shaped the organization's operations in particular during the Cold War , the decolonization process, and the dissolution of the Soviet Union . Among the major achievements of the organization is its work against racism, for example through influential statements on race starting with

6248-401: The organization: West Europe (5), Central America (1), North America (2), West Africa (1), East Asia (1), and East Europe (1). To date, there has been no elected Director-General from the remaining ten regions within UNESCO: Southeast Asia, South Asia, Central and North Asia, Middle East, North Africa, East Africa, Central Africa, South Africa, Australia-Oceania, and South America. The list of

6336-427: 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

6424-401: 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

6512-456: 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

6600-557: The site of the largest wine-producing appellation (region) in Canada. Cool-climate varieties such as Riesling, Chardonnay, Gamay Noir, Pinot Noir, and Cabernet Franc are among the more than 30 varietals produced across 13,600 hectares (33,606 acres). Three subappellations lie along the benchlands of the Niagara Escarpment: Short Hills Bench , Twenty Mile Bench , and Beamsville Bench . Northeastern Wisconsin, at

6688-467: The southeastern corner of Dodge County. Study of rock exposures and drillholes demonstrates that no displacement of the rock layers occurs at the escarpment, which is not a fault line but the result of unequal erosion . The escarpment's caprock is dolomitic limestone , also known as dolostone , which is more resistant and overlies weaker, more easily eroded shale as a weathering -resistant "cap". The escarpment formed over millions of years through

6776-697: The spine of the Bruce Peninsula and Manitoulin Island , as well as several smaller islands in northern Lake Huron, where it turns westwards into the Upper Peninsula of northern Michigan, south of Sault Ste. Marie . It extends down the Garden Peninsula and Potawatomi Islands into Wisconsin following the Door Peninsula and then continues more inland from the western coast of Lake Michigan until ending in

6864-873: The successor to the League of Nations ' International Committee on Intellectual Cooperation . UNESCO's founding mission, which was shaped by the events of World War II , is to advance peace , sustainable development and human rights by facilitating collaboration and dialogue among nations. It pursues this objective through five major programme areas: education, natural sciences , social / human sciences , culture and communication/information. UNESCO sponsors projects that improve literacy , provide technical training and education, advance science, protect independent media and press freedom , preserve regional and cultural history , and promote cultural diversity . The organization prominently helps establish and secure World Heritage Sites of cultural and natural importance. UNESCO

6952-400: 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

7040-474: The summer. The presence of the lake produces a vacuum of sorts during the growing season: warm air over the lake rises, sucking colder air off the land and creating offshore breezes. Cold air cannot settle over the vineyards and a constant flow of warmer air makes the growing season here longer than in other parts of the state. The escarpment's glacial soils are made up of gravel, sand, and clay over limestone bedrock. An aquifer provides mineral-rich ground water to

7128-422: 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 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

7216-526: The term dolostone was not recommended by the Glossary of Geology published by the American Geological Institute . In old USGS publications, dolomite 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

7304-506: The vines, encouraging deep root growth. In February 1990, the Niagara Escarpment was a designated World Biosphere Reserve by UNESCO , making it one of 12 in Canada. Development and land use on and adjacent to the escarpment is regulated by the Niagara Escarpment Commission , an agency of the Ontario government. Cliffs along the scarp face have the oldest forest ecosystem in eastern North America. The oldest tree in Ontario

7392-532: The virtually lifeless landmasses, eventually formed a limestone layer. During the Silurian period, some magnesium substituted for some of the calcium in the carbonates, slowly forming harder dolomite layers in the same fashion. This dolomite basin contains Lakes Michigan, Huron, and Erie. Worldwide sea levels were at their all-time maximum in the Ordovician; as the sea retreated, erosion inevitably began. The escarpment

7480-513: The western end of the escarpment, is the site of the 3,800 sq mi (9,800 km) Wisconsin Ledge AVA . Most of the region's vineyards lie upon the escarpment's eastern-facing slope that rises gently upward from the shores of Lake Michigan to the top of the Ledge, before dropping sharply off into Green Bay, and benefit greatly from constant air movement from Lake Michigan, which stores warmth during

7568-510: The world's living species, such as the komodo dragon of Indonesia, the panda of China, the bald eagle of North American countries, the aye-aye of Madagascar, the Asiatic lion of India, the kākāpō of New Zealand, and the mountain tapir of Colombia, Ecuador and Peru. UNESCO and its specialized institutions issue a number of magazines. Created in 1945, The UNESCO Courier magazine states its mission to "promote UNESCO's ideals, maintain

7656-617: Was a major obstacle in the construction of the Erie Canal in New York and was traversed by a series of locks; the community which grew up at the site thus became known as Lockport, New York . The Welland Canal allows ships to traverse the escarpment between Lake Erie and Lake Ontario on the Niagara Peninsula of Ontario. The canal also allowed Sea Lamprey , an invasive species native to Northern Atlantic Ocean, to enter Lake Erie and became

7744-577: Was readmitted by the UNESCO General Conference that July. UNESCO implements its activities through five programme areas: education, natural sciences, social and human sciences, culture, and communication and information. UNESCO does not accredit institutions of higher learning. The UNESCO transparency portal has been designed to enable public access to information regarding the Organization's activities, such as its aggregate budget for

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