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146-515: Hạ Long Bay or Halong Bay ( Vietnamese : Vịnh Hạ Long , IPA: [vînˀ hâːˀ lawŋm] ) is a UNESCO World Heritage Site and popular travel destination in Quảng Ninh province , Vietnam . The name Hạ Long means "descending dragon". Administratively, the bay belongs to Hạ Long city, Cẩm Phả city, and is a part of Vân Đồn district . The bay features thousands of limestone karsts and islets in various shapes and sizes. Hạ Long Bay

292-455: A Mohs hardness of 2 to 4, dense limestone can have a crushing strength of up to 180 MPa . For comparison, concrete typically has a crushing strength of about 40 MPa. Although limestones show little variability in mineral composition, they show great diversity in texture. However, most limestone consists of sand-sized grains in a carbonate mud matrix. Because limestones are often of biological origin and are usually composed of sediment that

438-463: A bloom of cyanobacteria or microalgae . However, stable isotope ratios in modern carbonate mud appear to be inconsistent with either of these mechanisms, and abrasion of carbonate grains in high-energy environments has been put forward as a third possibility. Formation of limestone has likely been dominated by biological processes throughout the Phanerozoic , the last 540 million years of

584-636: A minor syllable occurred). These fricatives were not present in Proto-Viet–Muong, as indicated by their absence in Mường , but were evidently present in the later Proto-Vietnamese stage. Subsequent loss of the minor-syllable prefixes phonemicized the fricatives. Ferlus 1992 proposes that originally there were both voiced and voiceless fricatives, corresponding to original voiced or voiceless stops, but Ferlus 2009 appears to have abandoned that hypothesis, suggesting that stops were softened and voiced at approximately

730-434: A carbonate rock outcrop can be estimated in the field by etching the surface with dilute hydrochloric acid. This etches away the calcite and aragonite, leaving behind any silica or dolomite grains. The latter can be identified by their rhombohedral shape. Crystals of calcite, quartz , dolomite or barite may line small cavities ( vugs ) in the rock. Vugs are a form of secondary porosity, formed in existing limestone by

876-616: A central quartz grain or carbonate mineral fragment. These likely form by direct precipitation of calcium carbonate onto the ooid. Pisoliths are similar to ooids, but they are larger than 2 mm in diameter and tend to be more irregular in shape. Limestone composed mostly of ooids is called an oolite or sometimes an oolitic limestone . Ooids form in high-energy environments, such as the Bahama platform, and oolites typically show crossbedding and other features associated with deposition in strong currents. Oncoliths resemble ooids but show

1022-449: A change in environment that increases the solubility of calcite. Dense, massive limestone is sometimes described as "marble". For example, the famous Portoro "marble" of Italy is actually a dense black limestone. True marble is produced by recrystallization of limestone during regional metamorphism that accompanies the mountain building process ( orogeny ). It is distinguished from dense limestone by its coarse crystalline texture and

1168-555: A classic fenglin landscape with heights ranging from 50–100 metres (160–330 ft), and height/width ratios of up to about six. Another specific feature of Hạ Long Bay is the abundance of lakes inside the limestone islands. For example, Dau Be island has six enclosed lakes. All these island lakes occupy drowned dolines within fengcong karst . Hạ Long Bay is located in northeastern Vietnam, from E106°55' to E107°37' and from N20°43' to N21°09'. The bay stretches from Quang Yen town, past Hạ Long city, Cẩm Phả city to Vân Đồn District ,

1314-949: A composition reflecting the organisms that produced them and the environment in which they were produced. Low-magnesium calcite skeletal grains are typical of articulate brachiopods , planktonic (free-floating) foraminifera, and coccoliths . High-magnesium calcite skeletal grains are typical of benthic (bottom-dwelling) foraminifera, echinoderms , and coralline algae . Aragonite skeletal grains are typical of molluscs , calcareous green algae , stromatoporoids , corals , and tube worms . The skeletal grains also reflect specific geological periods and environments. For example, coral grains are more common in high-energy environments (characterized by strong currents and turbulence) while bryozoan grains are more common in low-energy environments (characterized by quiet water). Ooids (sometimes called ooliths) are sand-sized grains (less than 2mm in diameter) consisting of one or more layers of calcite or aragonite around

1460-412: A considerable fraction of the limestone bed. At depths greater than 1 km (0.62 miles), burial cementation completes the lithification process. Burial cementation does not produce stylolites. When overlying beds are eroded, bringing limestone closer to the surface, the final stage of diagenesis takes place. This produces secondary porosity as some of the cement is dissolved by rainwater infiltrating

1606-489: A country, they had to fight against invaders. To assist the Vietnamese in defending their country, the gods sent a family of dragons as protectors. This family of dragons began spitting out jewels and jade . These jewels turned into the islands and islets dotting the bay, linking together to form a great wall against the invaders. Under magics, numerous rock mountains abruptly appeared on the sea, ahead of invaders' ships;

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1752-483: A drop of dilute hydrochloric acid is dropped on it. Dolomite is also soft but reacts only feebly with dilute hydrochloric acid, and it 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. Impurities (such as clay , sand, organic remains, iron oxide , and other materials) will cause limestones to exhibit different colors, especially with weathered surfaces. The makeup of

1898-637: A few million years, as this is the most stable form of calcium carbonate. Ancient carbonate formations of the Precambrian and Paleozoic contain abundant dolomite, but limestone dominates the carbonate beds of the Mesozoic and Cenozoic . Modern dolomite is quite rare. There is evidence that, while the modern ocean favors precipitation of aragonite, the oceans of the Paleozoic and middle to late Cenozoic favored precipitation of calcite. This may indicate

2044-455: A few thousand years. As rainwater mixes with groundwater, aragonite and high-magnesium calcite are converted to low-calcium calcite. Cementing of thick carbonate deposits by rainwater may commence even before the retreat of the sea, as rainwater can infiltrate over 100 km (60 miles) into sediments beneath the continental shelf. As carbonate sediments are increasingly deeply buried under younger sediments, chemical and mechanical compaction of

2190-419: A high density of 775 islets. The limestone in this bay has gone through 500 million years of formation in different conditions and environments. The evolution of the karst in this bay has taken 20 million years under the impact of the tropical wet climate. The geo-diversity of the environment in the area has created biodiversity , including a tropical evergreen biosystem and a seashore biosystem. Hạ Long Bay

2336-490: A high percentage of the mineral dolomite , CaMg(CO 3 ) 2 . Magnesian limestone is an obsolete and poorly-defined term used variously for dolomite, for limestone containing significant dolomite ( dolomitic limestone ), or for any other limestone containing a significant percentage of magnesium . Most limestone was formed in shallow marine environments, such as continental shelves or platforms , though smaller amounts were formed in many other environments. Much dolomite

2482-435: A limestone sample except in thin section and are less common in ancient limestones, possibly because compaction of carbonate sediments disrupts them. Limeclasts are fragments of existing limestone or partially lithified carbonate sediments. Intraclasts are limeclasts that originate close to where they are deposited in limestone, while extraclasts come from outside the depositional area. Intraclasts include grapestone , which

2628-471: A lower Mg/Ca ratio in the ocean water of those times. This magnesium depletion may be a consequence of more rapid sea floor spreading , which removes magnesium from ocean water. The modern ocean and the ocean of the Mesozoic have been described as "aragonite seas". Most limestone was formed in shallow marine environments, such as continental shelves or platforms . Such environments form only about 5% of

2774-525: A lower diversity of organisms and a greater fraction of silica and clay minerals characteristic of marls . The Green River Formation is an example of a prominent freshwater sedimentary formation containing numerous limestone beds. Freshwater limestone is typically micritic. Fossils of charophyte (stonewort), a form of freshwater green algae, are characteristic of these environments, where the charophytes produce and trap carbonates. Limestones may also form in evaporite depositional environments . Calcite

2920-447: A main vowel component followed by a shorter semivowel offglide /j/ or /w/ . There are restrictions on the high offglides: /j/ cannot occur after a front vowel (i, ê, e) nucleus and /w/ cannot occur after a back vowel (u, ô, o) nucleus. The correspondence between the orthography and pronunciation is complicated. For example, the offglide /j/ is usually written as i ; however, it may also be represented with y . In addition, in

3066-547: A marine and coastal ecosystem. Livistona halongensis , Impatiens halongensis , Chirita halongensis, Chirita hiepii, Chirita modesta, Paraboea halongensis , and Alpinia calcicola are among the seven endemic species found in the bay. There is also some bioluminescent plankton. The many islands that dot the bay are home to a great many other species, including (but likely not limited to): 477 magnoliales , 12 pteris , 20 salt marsh flora; and 4 amphibia , 10 reptilia , 40 aves , and 4 mammalia . Common aquatic species found in

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3212-399: A mature karst landscape developed during a warm, wet, tropical climate. The sequence of stages in the evolution of a karst landscape over a period of 20 million years requires a combination of several distinct elements including a massive thickness of limestone, a hot wet climate and slow overall tectonic up lift. The process of karst formation is divided into five stages, the second of which is

3358-523: A mechanism for dolomitization, with one 2004 review paper describing it bluntly as "a myth". Ordinary seawater is capable of converting calcite to dolomite, if the seawater is regularly flushed through the rock, as by the ebb and flow of tides (tidal pumping). Once dolomitization begins, it proceeds rapidly, so that there is very little carbonate rock containing mixed calcite and dolomite. Carbonate rock tends to be either almost all calcite/aragonite or almost all dolomite. About 20% to 25% of sedimentary rock

3504-482: A number of beautiful beaches on the smaller islands. A community of around 1,600 people live on Hạ Long Bay in four fishing villages: Cua Van, Ba Hang, Cong Tau and Vong Vieng in Hung Thang ward, Hạ Long city. They live on floating houses and are sustained through fishing and marine aquaculture (cultivating marine biota), plying the shallow waters for 200 species of fish and 450 different kinds of mollusks . Many of

3650-545: A number of fishing villages for sightseeing tours. Located within Hạ Long and Bái Tử Long are archaeological sites such as Mê Cung and Thiên Long. There are remains from mounds of mountain shellfish ( Cyclophorus ), spring shellfish ( Melania , also called Thiana ), some freshwater water mollusc and some rudimentary labour tools. The main way of life of Soi Nhụ's inhabitants included catching fish and shellfish, collecting fruits and digging for bulbs and roots. Their living environment

3796-448: A paper published in 1856. Later, in 1920, French-Polish linguist Jean Przyluski found that Mường is more closely related to Vietnamese than other Mon–Khmer languages, and a Viet–Muong subgrouping was established, also including Thavung , Chut , Cuoi , etc. The term "Vietic" was proposed by Hayes (1992), who proposed to redefine Viet–Muong as referring to a subbranch of Vietic containing only Vietnamese and Mường . The term " Vietic "

3942-448: A plausible source of mud. Another possibility is direct precipitation from the water. A phenomenon known as whitings occurs in shallow waters, in which white streaks containing dispersed micrite appear on the surface of the water. It is uncertain whether this is freshly precipitated aragonite or simply material stirred up from the bottom, but there is some evidence that whitings are caused by biological precipitation of aragonite as part of

4088-546: A policy to relocate the households living in the bay to resettle, in order to stabilize their life and to protect the landscape of the heritage zone. More than 300 households living in fishing villages in Hạ Long Bay have been relocated ashore in Khe Cá Resettlement Area, now known as Zone 8 (Hà Phong Ward, Hạ Long City) since May 2014. This project will continue to be implemented. The province will only retain

4234-546: A process of tonogenesis , in which distinctions formerly expressed by final consonants became phonemic tonal distinctions when those consonants disappeared. These characteristics have become part of many of the genetically unrelated languages of Southeast Asia; for example, Tsat (a member of the Malayo-Polynesian group within Austronesian ), and Vietnamese each developed tones as a phonemic feature. After

4380-449: A radial rather than layered internal structure, indicating that they were formed by algae in a normal marine environment. Peloids are structureless grains of microcrystalline carbonate likely produced by a variety of processes. Many are thought to be fecal pellets produced by marine organisms. Others may be produced by endolithic (boring) algae or other microorganisms or through breakdown of mollusc shells. They are difficult to see in

4526-642: A representative on the Government Council for Nationalities, an advisory body of the Czech Government for matters of policy towards national minorities and their members. It also grants the community the right to use Vietnamese with public authorities and in courts anywhere in the country. Vietnamese is taught in schools and institutions outside of Vietnam, a large part contributed by its diaspora . In countries with Vietnamese-speaking communities Vietnamese language education largely serves as

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4672-481: A role to link descendants of Vietnamese immigrants to their ancestral culture. In neighboring countries and vicinities near Vietnam such as Southern China, Cambodia, Laos, and Thailand, Vietnamese as a foreign language is largely due to trade, as well as recovery and growth of the Vietnamese economy. Since the 1980s, Vietnamese language schools ( trường Việt ngữ/ trường ngôn ngữ Tiếng Việt ) have been established for youth in many Vietnamese-speaking communities around

4818-473: A special feature of the karst of Hạ Long Bay. The dissolution process of sea water acting on the limestone and erosion by wave action creates notches at the base of the cliffs. In advantageous conditions, dissolution of the limestone allows the cliff notches to be steadily deepened and extended into caves. Many of these at sea level extend right through the limestone hills into drowned dolinas which are now tidal lakes. A distinguishing feature of marine notch caves

4964-519: A stage commonly termed Middle Vietnamese ( tiếng Việt trung đại ). The pronunciation of the "rime" of the syllable, i.e. all parts other than the initial consonant (optional /w/ glide, vowel nucleus, tone and final consonant), appears nearly identical between Middle Vietnamese and modern Hanoi pronunciation. On the other hand, the Middle Vietnamese pronunciation of the initial consonant differs greatly from all modern dialects, and in fact

5110-552: A third of the Vietnamese lexicon in all realms, and may account for as much as 60% of the vocabulary used in formal texts. Vietic languages were confined to the northern third of modern Vietnam until the "southward advance" ( Nam tiến ) from the late 15th century. The conquest of the ancient nation of Champa and the conquest of the Mekong Delta led to an expansion of the Vietnamese people and language, with distinctive local variations emerging. After France invaded Vietnam in

5256-485: Is bordered on the south and southeast by Lan Ha Bay, on the north by Hạ Long city, and on the west by Bai Tu Long Bay. The bay has a 120-kilometre-long (75 mi) coastline and is approximately 1,553 km (600 sq mi) in size with about 2,000 islets. The area designated by UNESCO as the World Natural Heritage Site incorporates 434 km (168 sq mi) with 775 islets, of which

5402-431: Is a center of a larger zone that includes Bai Tu Long Bay to the northeast, and Cát Bà Island to the southwest. These larger zones share a similar geological, geographical, geomorphological , climate, and cultural characters. Hạ Long Bay has an area of around 1,553 km (600 sq mi), including 1,969 islets, most of which are limestone. The core of the bay has an area of 334 km (129 sq mi) with

5548-416: Is a type of carbonate sedimentary rock which is the main source of the material lime . It is composed mostly of the minerals calcite and aragonite , which are different crystal forms of CaCO 3 . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as

5694-560: Is also favored on the seaward margin of shelves and platforms, where there is upwelling deep ocean water rich in nutrients that increase organic productivity. Reefs are common here, but when lacking, ooid shoals are found instead. Finer sediments are deposited close to shore. The lack of deep sea limestones is due in part to rapid subduction of oceanic crust, but is more a result of dissolution of calcium carbonate at depth. The solubility of calcium carbonate increases with pressure and even more with higher concentrations of carbon dioxide, which

5840-527: Is also spoken by the Jing people traditionally residing on three islands (now joined to the mainland) off Dongxing in southern Guangxi Province , China . A large number of Vietnamese speakers also reside in neighboring countries of Cambodia and Laos . In the United States, Vietnamese is the sixth most spoken language , with over 1.5 million speakers, who are concentrated in a handful of states. It

5986-455: Is an absolutely smooth and horizontal ceiling cut through the limestone. Some marine notch caves had not been not formed at present sea level, but old sea levels related to sea level changes in Holocene transgression, event to Pleistocene sea levels. Some of them preserved the development of old karstic foot caves in mainland environments or preserved the remnants of older phreatic caves. One of

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6132-482: Is an uncommon mineral in limestone, and siderite or other carbonate minerals are rare. However, the calcite in limestone often contains a few percent of magnesium . Calcite in limestone is divided into low-magnesium and high-magnesium calcite, with the dividing line placed at a composition of 4% magnesium. High-magnesium calcite retains the calcite mineral structure, which is distinct from dolomite. Aragonite does not usually contain significant magnesium. Most limestone

6278-412: Is as extensive as Hạ Long Bay. Some of the most remarkable geological events in Hạ Long Bay's history have occurred in the last 1,000 years, include the advance of the sea, the raising of the bay area, strong erosion that has formed coral, and, pure blue and heavily salted water. This process of erosion by seawater has deeply engraved the stone, contributing to its fantastic beauty. Present-day Hạ Long Bay

6424-555: Is between 2 and 2.2 metres (6.6 and 7.2 ft). Hạ Long Bay has the typical diurnal tide system (tide amplitude ranges from 3.5–4 metres or 11–13 feet). The salinity is from 31 to 34.5MT in the dry season and lower in the rainy season. Of the 1,969 islands in Hạ Long, only approximately 40 are inhabited. These islands range from tens to thousands of hectares in size, mainly in the East and Southeast of Hạ Long Bay. In recent decades, thousands of villagers have been starting to settle down on

6570-402: Is carbonate rock, and most of this is limestone. Limestone is found in sedimentary sequences as old as 2.7 billion years. However, the compositions of carbonate rocks show an uneven distribution in time in the geologic record. About 95% of modern carbonates are composed of high-magnesium calcite and aragonite. The aragonite needles in carbonate mud are converted to low-magnesium calcite within

6716-474: Is clusters of peloids cemented together by organic material or mineral cement. Extraclasts are uncommon, are usually accompanied by other clastic sediments, and indicate deposition in a tectonically active area or as part of a turbidity current . The grains of most limestones are embedded in a matrix of carbonate mud. This is typically the largest fraction of an ancient carbonate rock. Mud consisting of individual crystals less than 5 μm (0.20 mils) in length

6862-416: Is commonly white to gray in color. Limestone that is unusually rich in organic matter can be almost black in color, while traces of iron or manganese can give limestone an off-white to yellow to red color. The density of limestone depends on its porosity, which varies from 0.1% for the densest limestone to 40% for chalk. The density correspondingly ranges from 1.5 to 2.7 g/cm . Although relatively soft, with

7008-420: Is controlled largely by the amount of dissolved carbon dioxide ( CO 2 ) in the water. This is summarized in the reaction: Increases in temperature or decreases in pressure tend to reduce the amount of dissolved CO 2 and precipitate CaCO 3 . Reduction in salinity also reduces the solubility of CaCO 3 , by several orders of magnitude for fresh water versus seawater. Near-surface water of

7154-545: Is converted to low-magnesium calcite. Diagenesis is the likely origin of pisoliths , concentrically layered particles ranging from 1 to 10 mm (0.039 to 0.394 inches) in diameter found in some limestones. Pisoliths superficially resemble ooids but have no nucleus of foreign matter, fit together tightly, and show other signs that they formed after the original deposition of the sediments. Silicification occurs early in diagenesis, at low pH and temperature, and contributes to fossil preservation. Silicification takes place through

7300-503: Is deposited close to where it formed, classification of limestone is usually based on its grain type and mud content. Most grains in limestone are skeletal fragments of marine organisms such as coral or foraminifera . These organisms secrete structures made of aragonite or calcite, and leave these structures behind when they die. Other carbonate grains composing limestones are ooids , peloids , and limeclasts ( intraclasts and extraclasts  [ ca ] ). Skeletal grains have

7446-460: Is described as coquinite . Chalk is a soft, earthy, fine-textured limestone composed of the tests of planktonic microorganisms such as foraminifera, while marl is an earthy mixture of carbonates and silicate sediments. Limestone forms when calcite or aragonite precipitate out of water containing dissolved calcium, which can take place through both biological and nonbiological processes. The solubility of calcium carbonate ( CaCO 3 )

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7592-617: Is described as micrite . In fresh carbonate mud, micrite is mostly small aragonite needles, which may precipitate directly from seawater, be secreted by algae, or be produced by abrasion of carbonate grains in a high-energy environment. This is converted to calcite within a few million years of deposition. Further recrystallization of micrite produces microspar , with grains from 5 to 15 μm (0.20 to 0.59 mils) in diameter. Limestone often contains larger crystals of calcite, ranging in size from 0.02 to 0.1 mm (0.79 to 3.94 mils), that are described as sparry calcite or sparite . Sparite

7738-462: Is distinguished from micrite by a grain size of over 20 μm (0.79 mils) and because sparite stands out under a hand lens or in thin section as white or transparent crystals. Sparite is distinguished from carbonate grains by its lack of internal structure and its characteristic crystal shapes. Geologists are careful to distinguish between sparite deposited as cement and sparite formed by recrystallization of micrite or carbonate grains. Sparite cement

7884-741: Is home to 14 endemic floral species and 60 endemic faunal species. Historical research surveys have shown the presence of prehistoric human beings in this area tens of thousands years ago. The successive ancient cultures are the Soi Nhụ culture around 18,000–7,000 BC, the Cái Bèo culture 7,000–5,000 BC and the Hạ Long culture 5,000–3,500 years ago. Hạ Long Bay also marked some important events in Vietnamese history , with many artifacts found in Bài Thơ mountain, Đầu Gỗ cave, and Bãi Cháy. Nguyễn Trãi praised

8030-415: Is notated i or y (with the difference between the two often indicating differences in the quality or length of the preceding vowel), and after /ð/ and /β/ , where it is notated ĕ . This ĕ , and the /j/ it notated, have disappeared from the modern language. Note that b [ɓ] and p [p] never contrast in any position, suggesting that they are allophones. The language also has three clusters at

8176-534: Is often mistaken for a tilde in modern reproductions of early Vietnamese writing. As a result of emigration , Vietnamese speakers are also found in other parts of Southeast Asia , East Asia , North America , Europe , and Australia . Vietnamese has also been officially recognized as a minority language in the Czech Republic . As the national language, Vietnamese is the lingua franca in Vietnam. It

8322-582: Is often mistakenly thought as being an monosyllabic language, Vietnamese words typically consist of from one to many as eight individual morphemes or syllables; the majority of Vietnamese vocabulary are disyllabic and trisyllabic words. Vietnamese is written using the Vietnamese alphabet ( chữ Quốc ngữ ). The alphabet is based on the Latin script and was officially adopted in the early 20th century during French rule of Vietnam . It uses digraphs and diacritics to mark tones and some phonemes . Vietnamese

8468-441: Is on Bo Hon Island. From its truncated entrance chambers on a ledge high on the cliff, a passage of more than 10m high and wide descends to the south. Tam Cung is a large phreatic fissure cave that developed in the bedding planes of the limestone dividing the fissure cave into three chambers. Lau Dai is a cave with a complex of passages extending over 300 meters on the south side of Con Ngua Island. Thien Cung and Dau Go are remnants of

8614-560: Is one of the first minerals to precipitate in marine evaporites. Most limestone is formed by the activities of living organisms near reefs, but the organisms responsible for reef formation have changed over geologic time. For example, stromatolites are mound-shaped structures in ancient limestones, interpreted as colonies of cyanobacteria that accumulated carbonate sediments, but stromatolites are rare in younger limestones. Organisms precipitate limestone both directly as part of their skeletons, and indirectly by removing carbon dioxide from

8760-473: Is otherwise chemically fairly pure, with clastic sediments (mainly fine-grained quartz and clay minerals ) making up less than 5% to 10% of the composition. Organic matter typically makes up around 0.2% of a limestone and rarely exceeds 1%. Limestone often contains variable amounts of silica in the form of chert or siliceous skeletal fragments (such as sponge spicules, diatoms , or radiolarians ). Fossils are also common in limestone. Limestone

8906-451: Is probably second in the entire world only to Yangshuo , in China. However, Hạ Long Bay has also been invaded by the sea so that the geomorphology of its limestone islands are, at least in part, the consequence of marine erosion. The marine invasion distinguishes Hạ Long Bay and makes it unique in the world. There are other areas of submerged karst towers which were invaded by the sea, but none

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9052-472: Is produced by decaying organic matter settling into the deep ocean that is not removed by photosynthesis in the dark depths. As a result, there is a fairly sharp transition from water saturated with calcium carbonate to water unsaturated with calcium carbonate, the lysocline , which occurs at the calcite compensation depth of 4,000 to 7,000 m (13,000 to 23,000 feet). Below this depth, foraminifera tests and other skeletal particles rapidly dissolve, and

9198-476: Is pronounced with one of six inherent tones , centered on the main vowel or group of vowels. Tones differ in: Tone is indicated by diacritics written above or below the vowel (most of the tone diacritics appear above the vowel; except the nặng tone dot diacritic goes below the vowel). The six tones in the northern varieties (including Hanoi), with their self-referential Vietnamese names, are: Limestone Limestone ( calcium carbonate CaCO 3 )

9344-518: Is secondary dolomite, formed by chemical alteration of limestone. Limestone is exposed over large regions of the Earth's surface, and because limestone is slightly soluble in rainwater, these exposures often are eroded to become karst landscapes. Most cave systems are found in limestone bedrock. Limestone has numerous uses: as a chemical feedstock for the production of lime used for cement (an essential component of concrete ), as aggregate for

9490-410: Is significantly closer to the modern Saigon dialect than the modern Hanoi dialect. The following diagram shows the orthography and pronunciation of Middle Vietnamese: ^1 [p] occurs only at the end of a syllable. ^2 This letter, ⟨ ꞗ ⟩ , is no longer used. ^3 [j] does not occur at the beginning of a syllable, but can occur at the end of a syllable, where it

9636-544: Is surface water, groundwater and thermal mineral water on the shore of the Hạ Long – Bái Tử Long Bays, as well as other environmental resources. In terms of marine geology, this area is recorded as an especially coastal sedimentary environment. In the alkaline seawater environment, the chemical denudation process of calcium carbonate proceeds rapidly, creating wide, strangely shaped marine notches. The bottom surface sediments are various from clay mud to sand, however, silty mud and clay mud dominate in distribution. Especially,

9782-408: Is the first language of the majority of the Vietnamese population, as well as a first or second language for the country's ethnic minority groups . In the Czech Republic , Vietnamese has been recognized as one of 14 minority languages, on the basis of communities that have resided in the country either traditionally or on a long-term basis. This status grants the Vietnamese community in the country

9928-406: Is the old karstic foot caves which include Trinh Lu, Bo Nau, Tien Ong and Trong caves. Foot caves are a ubiquitous feature of karst landscapes which have reached a stage of widespread lateral undercutting at base level. They may extend back into maze caves of stream caves draining from larger cave systems within the limestone. They are distinguished by the main elements of their passages being close to

10074-504: Is the result of this long process of geological evolution that has been influenced by so many factors. Due to all these factors, tourists visiting Hạ Long Bay are not only treated to one of the natural wonders of the world, but also to a precious geological museum that has been naturally preserved in the open air for the last 300 million years. Two ecosystems coexist in Ha Long Bay: a tropical, moist, evergreen rainforest ecosystem and

10220-653: Is the third-most spoken language in Texas and Washington; fourth-most in Georgia, Louisiana, and Virginia; and fifth-most in Arkansas and California. Vietnamese is the third most spoken language in Australia other than English, after Mandarin and Arabic. In France, it is the most spoken Asian language and the eighth most spoken immigrant language at home. Vietnamese is the sole official and national language of Vietnam. It

10366-510: Is threatening many endangered species of fish. Local government and businesses are aware of the problems and many measures have been taken to minimise the impact of tourism on the bay environment for sustainable economic growth like introducing eco-friendly tours and tight waste control on resorts. In 1962, the Vietnam Ministry of Culture, Sport and Tourism designated Hạ Long Bay a 'Renowned National Landscape Monument'. Hạ Long Bay

10512-413: Is used, among others, by Gérard Diffloth , with a slightly different proposal on subclassification, within which the term "Viet–Muong" refers to a lower subgrouping (within an eastern Vietic branch) consisting of Vietnamese dialects, Mường dialects, and Nguồn (of Quảng Bình Province ). Austroasiatic is believed to have dispersed around 2000 BC. The arrival of the agricultural Phùng Nguyên culture in

10658-446: Is written with two Chinese characters or in a composite character made of two different characters. This conveys the transformation of the Vietnamese lexicon from sesquisyllabic to fully monosyllabic under the pressure of Chinese linguistic influence, characterized by linguistic phenomena such as the reduction of minor syllables; loss of affixal morphology drifting towards analytical grammar; simplification of major syllable segments, and

10804-988: The Mon–Khmer branch of the Austroasiatic language family (which also includes the Khmer language spoken in Cambodia , as well as various smaller and/or regional languages , such as the Munda and Khasi languages spoken in eastern India, and others in Laos , southern China and parts of Thailand). In 1850, British lawyer James Richardson Logan detected striking similarities between the Korku language in Central India and Vietnamese. He suggested that Korku , Mon , and Vietnamese were part of what he termed "Mon–Annam languages" in

10950-605: The Red River Delta at that time may correspond to the Vietic branch. This ancestral Vietic was typologically very different from later Vietnamese. It was polysyllabic, or rather sesquisyllabic , with roots consisting of a reduced syllable followed by a full syllable, and featured many consonant clusters. Both of these features are found elsewhere in Austroasiatic and in modern conservative Vietic languages south of

11096-597: The Vietnamese orthography with the phonetic pronunciation to the right. Some consonant sounds are written with only one letter (like "p"), other consonant sounds are written with a digraph (like "ph"), and others are written with more than one letter or digraph (the velar stop is written variously as "c", "k", or "q"). In some cases, they are based on their Middle Vietnamese pronunciation; since that period, ph and kh (but not th ) have evolved from aspirated stops into fricatives (like Greek phi and chi ), while d and gi have collapsed and converged together (into /z/ in

11242-466: The 19th century, the name Hạ Long Bay had not been recorded in the old books of the country. It has been called other names such as An Bang, Lục Thủy, and Vân Đồn. In the late 19th century, the name Hạ Long Bay appeared on the Maritime Map of France. The French-language Hai Phong News reported "Dragon appears on Hạ Long Bay". According to local legend, when Vietnam had just started to develop into

11388-509: The Ba Ham lakes lying within its fengcong karst. The Bay contains examples of the landscape elements of fengcong, fenglin and karst plain. These are not separate evolutionary stages but the result of natural non – uniform processes in the denudation of a large mass of limestone. Marine erosion created the notches which in some places have been enlarged into caves. The marine notch is a feature of limestone coastline but, in Hạ Long Bay, it has created

11534-496: The Earth's history. Limestone may have been deposited by microorganisms in the Precambrian , prior to 540 million years ago, but inorganic processes were probably more important and likely took place in an ocean more highly oversaturated in calcium carbonate than the modern ocean. Diagenesis is the process in which sediments are compacted and turned into solid rock . During diagenesis of carbonate sediments, significant chemical and textural changes take place. For example, aragonite

11680-565: The French colonial era. The following diagram shows the phonology of Proto–Viet–Muong (the nearest ancestor of Vietnamese and the closely related Mường language ), along with the outcomes in the modern language: ^1 According to Ferlus, * /tʃ/ and * /ʄ/ are not accepted by all researchers. Ferlus 1992 also had additional phonemes * /dʒ/ and * /ɕ/ . ^2 The fricatives indicated above in parentheses developed as allophones of stop consonants occurring between vowels (i.e. when

11826-467: The Quaternary Period. Due to a simultaneous combination of ideal factors such as thick, pale, grey, and strong limestone layers, which are formed by fine-grained materials; hot and moist climate and slow tectonic process as a whole; Hạ Long Bay has had a complete karst evolution for 20 million years. There are many types of karst topography in the bay, such as karst field . Hạ Long Bay is

11972-727: The Red River Delta and into the adjacent uplands, possibly to escape Chinese encroachment. The oldest layer of loans from Chinese into northern Vietic (which would become the Viet–Muong subbranch) date from this period. The northern Vietic varieties thus became part of the Mainland Southeast Asia linguistic area , in which languages from genetically unrelated families converged toward characteristics such as isolating morphology and similar syllable structure. Many languages in this area, including Viet–Muong, underwent

12118-527: The Red River area. The language was non-tonal, but featured glottal stop and voiceless fricative codas. Borrowed vocabulary indicates early contact with speakers of Tai languages in the last millennium BC, which is consistent with genetic evidence from Dong Son culture sites. Extensive contact with Chinese began from the Han dynasty (2nd century BC). At this time, Vietic groups began to expand south from

12264-735: The World Heritage List according to its outstanding examples representing major stages of the Earth's history and its original limestone karstic geomorphologic features. Hạ Long Bay and its adjacent areas consist of a part of the Sino-Vietnamese composite terrane having its development history from pre-Cambrian up to present day. During Phanerozoic, terrigenous, volcanogenic and cherty -carbonate sediments containing in abundance graptolites , bivalves, brachiopods , fishes, foraminiferans , corals, radiolarias , and flora, separated from one from another by 10 stratigraphic gaps, but

12410-430: The accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite , a closely related rock, which contains

12556-434: The base of roads, as white pigment or filler in products such as toothpaste or paint, as a soil conditioner , and as a popular decorative addition to rock gardens . Limestone formations contain about 30% of the world's petroleum reservoirs . Limestone is composed mostly of the minerals calcite and aragonite , which are different crystal forms of calcium carbonate ( CaCO 3 ). Dolomite , CaMg(CO 3 ) 2 ,

12702-567: The bay include: cuttlefish ( mực ); oyster ( hào ); cyclinae ( ngán ); prawns (penaeidea ( tôm he ), panulirus ( tôm hùm ), parapenaeopsis ( tôm sắt ), etc.); sipunculoideas ( sá sùng ); nerita ( ốc đĩa ); charonia tritonis ( ốc tù và ); and cà sáy . A new species of sponge, Cladocroce pansinii , was discovered in underwater caves attached to the bay in 2023. With an increasing tourist trade, mangroves and seagrass beds have been cleared and jetties and wharves have been built for tourist boats. Game fishing , often near coral reefs,

12848-608: The beauty of Hạ Long Bay 500 years ago in his verse Lộ nhập Vân Đồn , in which he called it "a rock wonder in the sky". In 1962, the Ministry of Culture, Sports and Tourism of North Vietnam listed Hạ Long Bay in the National Relics and Landscapes publication. In 1994, the core zone of Hạ Long Bay was listed as a World Heritage Site under Criterion VII, and was listed for a second time under Criterion VIII. The name Hạ Long ( chữ Hán : 下龍) means "descending dragon". Before

12994-657: The beds. This may include the formation of vugs , which are crystal-lined cavities within the limestone. Diagenesis may include conversion of limestone to dolomite by magnesium-rich fluids. There is considerable evidence of replacement of limestone by dolomite, including sharp replacement boundaries that cut across bedding. The process of dolomitization remains an area of active research, but possible mechanisms include exposure to concentrated brines in hot environments ( evaporative reflux ) or exposure to diluted seawater in delta or estuary environments ( Dorag dolomitization ). However, Dorag dolomitization has fallen into disfavor as

13140-475: The beginning of syllables, which have since disappeared: Most of the unusual correspondences between spelling and modern pronunciation are explained by Middle Vietnamese. Note in particular: De Rhodes's orthography also made use of an apex diacritic, as in o᷄ and u᷄ , to indicate a final labial-velar nasal /ŋ͡m/ , an allophone of /ŋ/ that is peculiar to the Hanoi dialect to the present day. This diacritic

13286-464: The boundary between Devonian and Carboniferous has been considered as continuous. The limestone karstic geomorphology of the bay has developed since the Miocene , especially the cone-shaped hills (fengcong), or isolated high limestone karst towers (fenglin) with many remnants of old phreatic caves, old karstic foot caves, and marine notch caves forming magnificent limestone karst landforms unique to

13432-417: The carbonate materials originated from organisms make up 60 to 65% sedimentary content. The surface sediments of coral reefs are mainly sand and pebbles, of which the carbonate materials account for more than 90%. The intertidal zone sediments are various, from clay mud to sand and gravel, depending on distinguished sedimentary environments such as mangrove marshes, tidal flats, beaches etc. At the small beaches,

13578-498: The change of suprasegment instruments. For example, the modern Vietnamese word "trời" (heaven) was read as *plời in Old/Ancient Vietnamese and as blời in Middle Vietnamese. The writing system used for Vietnamese is based closely on the system developed by Alexandre de Rhodes for his 1651 Dictionarium Annamiticum Lusitanum et Latinum . It reflects the pronunciation of the Vietnamese of Hanoi at that time,

13724-486: The core zone is delimited by 69 points: Dau Go island on the west, Ba Ham lake on the south and Cong Tay island on the east. The protected area is from the Cái Dăm petrol store to Quang Hanh ward, Cẩm Phả city and the surrounding zone. The climate of the bay is tropical, wet, sea islands, with two seasons: hot and moist summer, dry and cold winter. The average temperature is from 15–25 °C (59–77 °F), and annual rainfall

13870-466: The daughter languages from distinctions in the initial and final consonants. Vietnamese tones developed as follows: Glottal-ending syllables ended with a glottal stop /ʔ/ , while fricative-ending syllables ended with /s/ or /h/ . Both types of syllables could co-occur with a resonant (e.g. /m/ or /n/ ). At some point, a tone split occurred, as in many other mainland Southeast Asian languages . Essentially, an allophonic distinction developed in

14016-466: The depositional fabric of carbonate rocks. Dunham divides the rocks into four main groups based on relative proportions of coarser clastic particles, based on criteria such as whether the grains were originally in mutual contact, and therefore self-supporting, or whether the rock is characterized by the presence of frame builders and algal mats. Unlike the Folk scheme, Dunham deals with the original porosity of

14162-469: The deposits are highly porous, so that they have a spongelike texture, they are typically described as tufa . Secondary calcite deposited by supersaturated meteoric waters ( groundwater ) in caves is also sometimes described as travertine. This produces speleothems , such as stalagmites and stalactites . Coquina is a poorly consolidated limestone composed of abraded pieces of coral , shells , or other fossil debris. When better consolidated, it

14308-442: The diphthongs [āj] and [āːj] the letters y and i also indicate the pronunciation of the main vowel: ay = ă + /j/ , ai = a + /j/ . Thus, tay "hand" is [tāj] while tai "ear" is [tāːj] . Similarly, u and o indicate different pronunciations of the main vowel: au = ă + /w/ , ao = a + /w/ . Thus, thau "brass" is [tʰāw] while thao "raw silk" is [tʰāːw] . The consonants that occur in Vietnamese are listed below in

14454-402: The dragon's children wriggled their tails violently was called Bạch Long Vĩ island ( Bạch : white-color of the foam made when Dragon's children wriggled, Long : dragon, Vĩ : tail), present-day Tra Co peninsula, Móng Cái . The bay consists of a dense cluster of some 1,600 limestone monolithic islands each topped with thick jungle vegetation, rising spectacularly from the ocean. Several of

14600-406: The earth's oceans are oversaturated with CaCO 3 by a factor of more than six. The failure of CaCO 3 to rapidly precipitate out of these waters is likely due to interference by dissolved magnesium ions with nucleation of calcite crystals, the necessary first step in precipitation. Precipitation of aragonite may be suppressed by the presence of naturally occurring organic phosphates in

14746-399: The first refers to the grains and the second to the cement. For example, a limestone consisting mainly of ooids, with a crystalline matrix, would be termed an oosparite. It is helpful to have a petrographic microscope when using the Folk scheme, because it is easier to determine the components present in each sample. Robert J. Dunham published his system for limestone in 1962. It focuses on

14892-572: The formation of distinctive minerals from the silica and clay present in the original limestone. Two major classification schemes, the Folk and Dunham, are used for identifying the types of carbonate rocks collectively known as limestone. Robert L. Folk developed a classification system that places primary emphasis on the detailed composition of grains and interstitial material in carbonate rocks . Based on composition, there are three main components: allochems (grains), matrix (mostly micrite), and cement (sparite). The Folk system uses two-part names;

15038-455: The formation of the distinctive do line karst. This is followed by the development of fengcong karst, which can be seen in the groups of hills on Bo Hon and Dau Be Inland. These cones with sloping sides average 100m in height with the tallest exceeding 200m. Fenglin karst is characterized by steep separate towers. The hundreds of rocky islands that form the beautiful and famous landscape of the Bay are

15184-414: The forward ships struck the rocks and each other. After winning the battle, the dragons were interested in peaceful sightseeing of the Earth, and then decided to live in this bay. The place where the mother dragon descended was named Hạ Long, the place where the dragon's children attended upon their mother was called Bái Tử Long island ( Bái : attend upon, Tử : children, Long : dragon), and the place where

15330-429: The geologic record are called bioherms . Many are rich in fossils, but most lack any connected organic framework like that seen in modern reefs. The fossil remains are present as separate fragments embedded in ample mud matrix. Much of the sedimentation shows indications of occurring in the intertidal or supratidal zones, suggesting sediments rapidly fill available accommodation space in the shelf or platform. Deposition

15476-427: The horizontal and are commonly related to denuded or accumulated terraces at the old base levels. Trinh Nu, which is one of the larger foot caves in Hạ Long Bay with its ceiling at about 12m above sea level and about 80m in length, was developed in multiple stages. Bo Nau, a horizontal cave containing old stalactite deposits, cuts across the 25o dip of the bedding plane. The third group is the marine notch caves which're

15622-411: The individual towers of a classic Fenglin landscape where the intervening plains have been submerged by the sea. Most towers reach a height of between 50 and 100m with a height to width ratio of about 6. The karst dolines were flooded by the sea, becoming the abundance of lakes that lie within the limestone islands. For example, Dau Be island at the mouth of the Bay has six enclosed lakes including those of

15768-498: The islands are hollow, with enormous caves. Hang Dau Go (Wooden Stakes cave) is the largest grotto in the Hạ Long area. French tourists visited in the late 19th century, and named the cave Grotte des Merveilles . Its three large chambers contain large numerous stalactites and stalagmites (as well as 19th-century French graffiti ). There are two bigger islands, Tuần Châu and Cát Bà , that have permanent inhabitants, as well as tourist facilities including hotels and beaches. There are

15914-409: The islands have acquired their names as a result of their unusual shapes. Such names include Voi Islet (elephant), Ga Choi Islet ( fighting cock ), Khi Islet ( monkey ), and Mai Nha Islet (roof). 989 of the islands have been given names. Birds and land animals including bantams , antelopes , monkeys, and lizards also live on some of the islands. Almost all these islands are as individual towers in

16060-629: The islands, the Vietnamese army stopped the Chinese invaders from landing. In 1288, General Trần Hưng Đạo stopped Mongol ships from sailing up the nearby Bạch Đằng River by placing steel-tipped wooden stakes at high tide, sinking the Mongol Kublai Khan 's fleet. Hạ Long Bay was the site of the first ever raising of the new national flag of the Provisional Central Government of Vietnam on 5 June 1948 during

16206-446: The late 19th century, French gradually replaced Literary Chinese as the official language in education and government. Vietnamese adopted many French terms, such as đầm ('dame', from madame ), ga ('train station', from gare ), sơ mi ('shirt', from chemise ), and búp bê ('doll', from poupée ), resulting in a language that was Austroasiatic but with major Sino-influences and some minor French influences from

16352-481: The lives of Hạ Long Bay inhabitants have much improved due to new travel businesses. Residents of the floating villages around Hạ Long Bay now offer bedrooms for rent, boat tours, and fresh seafood meals to tourists. While this is an isolating, back-breaking lifestyle, floating village residents are considered wealthy compared to residents of other Hạ Long Bay islands. At present , the Quảng Ninh provincial government has

16498-427: The main syllable). When a minor syllable occurred, the main syllable's initial consonant was intervocalic and as a result suffered lenition , becoming a voiced fricative. The minor syllables were eventually lost, but not until the tone split had occurred. As a result, words in modern Vietnamese with voiced fricatives occur in all six tones, and the tonal register reflects the voicing of the minor-syllable prefix and not

16644-488: The mature landscape. Within Hạ Long Bay, the main accessible caves are the older passages that survive from the time when the karst was evolving through its various stages of fengcong and fenglin . Three main types of caves can be recognized in the limestone islands (Waltham, T. 1998): The first group consists of old phreatic caves which include Sung Sot, Tam Cung, Lau Dai, Thien Cung, Dau Go, Hoang Long, Thien Long. Nowadays, these caves lie at various heights. Sung Sot cave

16790-477: The modern tidal level. It has passed through many stages in its formation. The karst landscape of Hạ Long Bay is of international significance and of fundamental importance to the science of geomorphology. The fenglin tower karst, which is the type present in much of Hạ Long Bay, is the most extreme form of limestone landscape development. If these karst landscapes are broadly compared in terms of their height, steepness and number of their limestone towers, Hạ Long Bay

16936-544: The most unusual features of Hạ Long Bay is the Bo Ham lake group of hidden lakes and their connecting tunnel – notch caves in Dau Be Island. From the island's perimeter cliff a cave, 10m wide at water level and curving so that it is almost completely dark, extends about 150m to Lake 1. Luon Cave is on Bo Hon Island and extends 50m meters to an enclosed tidal lake. It has a massive stalactite hanging 2m down and truncated at

17082-497: The north and /j/ in the south). Not all dialects of Vietnamese have the same consonant in a given word (although all dialects use the same spelling in the written language). See the language variation section for further elaboration. Syllable-final orthographic ch and nh in Vietnamese has had different analyses. One analysis has final ch , nh as being phonemes /c/, /ɲ/ contrasting with syllable-final t , c /t/, /k/ and n , ng /n/, /ŋ/ and identifies final ch with

17228-410: The ocean basins, but limestone is rarely preserved in continental slope and deep sea environments. The best environments for deposition are warm waters, which have both a high organic productivity and increased saturation of calcium carbonate due to lower concentrations of dissolved carbon dioxide. Modern limestone deposits are almost always in areas with very little silica-rich sedimentation, reflected in

17374-405: The plain-voiced stops became voiceless and the allotones became new phonemic tones. The implosive stops were unaffected, and in fact developed tonally as if they were unvoiced. (This behavior is common to all East Asian languages with implosive stops.) As noted above, Proto-Viet–Muong had sesquisyllabic words with an initial minor syllable (in addition to, and independent of, initial clusters in

17520-651: The pristine islands and build new communities such as Sa Tô Island (Hạ Long City) and Thắng Lợi Island (Vân Đồn district). The population of Hạ Long Bay is about 1,540, mainly in Cửa Vạn, Ba Hang and Cặp Dè fishing villages (Hùng Thắng Ward, Hạ Long City). Residents of the bay mostly live on boats and rafts buoyed by tires and plastic jugs to facilitate the fishing, cultivating and breeding of aquatic and marine species. Fish require feeding every other day for up to three years, when they are eventually sold to local seafood restaurants for up to 300,000 Vietnamese dong per kilogram. Today,

17666-426: The reaction: Fossils are often preserved in exquisite detail as chert. Cementing takes place rapidly in carbonate sediments, typically within less than a million years of deposition. Some cementing occurs while the sediments are still under water, forming hardgrounds . Cementing accelerates after the retreat of the sea from the depositional environment, as rainwater infiltrates the sediment beds, often within just

17812-482: The relative purity of most limestones. Reef organisms are destroyed by muddy, brackish river water, and carbonate grains are ground down by much harder silicate grains. Unlike clastic sedimentary rock, limestone is produced almost entirely from sediments originating at or near the place of deposition. Limestone formations tend to show abrupt changes in thickness. Large moundlike features in a limestone formation are interpreted as ancient reefs , which when they appear in

17958-460: The rock. The Dunham scheme is more useful for hand samples because it is based on texture, not the grains in the sample. A revised classification was proposed by Wright (1992). It adds some diagenetic patterns to the classification scheme. Travertine is a term applied to calcium carbonate deposits formed in freshwater environments, particularly waterfalls , cascades and hot springs . Such deposits are typically massive, dense, and banded. When

18104-546: The same except that ơ [əː] is of normal length while â [ə] is short – the same applies to the vowels long a [aː] and short ă [a] . The centering diphthongs are formed with only the three high vowels (i, ư, u). They are generally spelled as ia, ưa, ua when they end a word and are spelled iê, ươ, uô, respectively, when they are followed by a consonant. In addition to single vowels (or monophthongs ) and centering diphthongs, Vietnamese has closing diphthongs and triphthongs . The closing diphthongs and triphthongs consist of

18250-410: The same old cave system. They both survive in the northern part of Dau Go Island at between 20 and 50m above sea level. Thien Cung has one large chamber more than 100m long, blocked at its ends and almost subdivided into smaller chambers by a massive wall of stalactites and stalagmites. Dau Go is a single large tunnel descending along a major set of fractures to a massive choke. The second group of caves

18396-473: The same time, according to the following pattern: ^3 In Middle Vietnamese , the outcome of these sounds was written with a hooked b (ꞗ), representing a /β/ that was still distinct from v (then pronounced /w/ ). See below. ^4 It is unclear what this sound was. According to Ferlus 1992, in the Archaic Vietnamese period (c. 10th century AD, when Sino-Vietnamese vocabulary

18542-408: The sand sediments may be dominated quartz or carbonate materials. The sediment layers of the intertidal zone, the upper sea bed with a plain surface conserving ancient rivers, the systems of caves and their sediments, traces of ancient marine action forming distinctive notches, beaches and marine terraces, and mangrove swamps are important evidence of geological events and processes taking place during

18688-479: The sediments increases. Chemical compaction takes place by pressure solution of the sediments. This process dissolves minerals from points of contact between grains and redeposits it in pore space, reducing the porosity of the limestone from an initial high value of 40% to 80% to less than 10%. Pressure solution produces distinctive stylolites , irregular surfaces within the limestone at which silica-rich sediments accumulate. These may reflect dissolution and loss of

18834-662: The sediments of the ocean floor abruptly transition from carbonate ooze rich in foraminifera and coccolith remains ( Globigerina ooze) to silicic mud lacking carbonates. In rare cases, turbidites or other silica-rich sediments bury and preserve benthic (deep ocean) carbonate deposits. Ancient benthic limestones are microcrystalline and are identified by their tectonic setting. Fossils typically are foraminifera and coccoliths. No pre-Jurassic benthic limestones are known, probably because carbonate-shelled plankton had not yet evolved. Limestones also form in freshwater environments. These limestones are not unlike marine limestone, but have

18980-607: The signing of the Halong Bay Agreements ( Accords de la baie d’Along ) by High Commissioner Emile Bollaert and President Nguyễn Văn Xuân . During the Vietnam War , many of the channels between the islands were heavily mined by the United States Navy , some of which continue to pose threats to shipping routes in the present day. In 2000, UNESCO's World Heritage Committee inscribed Hạ Long Bay in

19126-853: The site that must be addressed. In 2012, the New 7 Wonders Foundation officially named Hạ Long Bay as one of the New 7 Wonders of Nature . Hạ Long Bay is also a part of the Club of the Most Beautiful Bays of the World. In writings about Hạ Long Bay, the following Vietnamese writers wrote: "Hạ Long, Bái Tử Long - Dragons were hidden, only stones still remain On the moonlight nights, stones meditate as men do..." Lord Trịnh Cương overflowed with emotion: "Mountains are glistened by water shadow, water spills all over

19272-624: The sky". The inhabitants of the bay and its adjacent city have transmitted numerous ancient tales explaining names given to various isles and caves in the bay. Vietnamese language Like many languages in Southeast Asia and East Asia , Vietnamese is highly analytic and is tonal . It has head-initial directionality, with subject–verb–object order and modifiers following the words they modify. It also uses noun classifiers . Its vocabulary has had significant influence from Middle Chinese and loanwords from French . Although it

19418-487: The split from Muong around the end of the first millennium AD, the following stages of Vietnamese are commonly identified: After expelling the Chinese at the beginning of the 10th century, the Ngô dynasty adopted Classical Chinese as the formal medium of government, scholarship and literature. With the dominance of Chinese came wholesale importation of Chinese vocabulary. The resulting Sino-Vietnamese vocabulary makes up about

19564-505: The syllable-initial ch /c/ . The other analysis has final ch and nh as predictable allophonic variants of the velar phonemes /k/ and /ŋ/ that occur after the upper front vowels i /i/ and ê /e/ ; although they also occur after a , but in such cases are believed to have resulted from an earlier e /ɛ/ which diphthongized to ai (cf. ach from aic , anh from aing ). (See Vietnamese phonology: Analysis of final ch , nh for further details.) Each Vietnamese syllable

19710-579: The tones, whereby the tones in syllables with voiced initials were pronounced differently from those with voiceless initials. (Approximately speaking, the voiced allotones were pronounced with additional breathy voice or creaky voice and with lowered pitch. The quality difference predominates in today's northern varieties, e.g. in Hanoi , while in the southern varieties the pitch difference predominates, as in Ho Chi Minh City .) Subsequent to this,

19856-422: The voicing of the main-syllable stop in Proto-Viet–Muong that produced the fricative. For similar reasons, words beginning with /l/ and /ŋ/ occur in both registers. (Thompson 1976 reconstructed voiceless resonants to account for outcomes where resonants occur with a first-register tone, but this is no longer considered necessary, at least by Ferlus.) Old Vietnamese/Ancient Vietnamese was a Vietic language which

20002-533: The water by photosynthesis and thereby decreasing the solubility of calcium carbonate. Limestone shows the same range of sedimentary structures found in other sedimentary rocks. However, finer structures, such as lamination , are often destroyed by the burrowing activities of organisms ( bioturbation ). Fine lamination is characteristic of limestone formed in playa lakes , which lack the burrowing organisms. Limestones also show distinctive features such as geopetal structures , which form when curved shells settle to

20148-553: The water. Although ooids likely form through purely inorganic processes, the bulk of CaCO 3 precipitation in the oceans is the result of biological activity. Much of this takes place on carbonate platforms . The origin of carbonate mud, and the processes by which it is converted to micrite, continue to be a subject of research. Modern carbonate mud is composed mostly of aragonite needles around 5 μm (0.20 mils) in length. Needles of this shape and composition are produced by calcareous algae such as Penicillus , making this

20294-452: The world such as in the United States , Germany and France . Vietnamese has a large number of vowels . Below is a vowel diagram of Vietnamese from Hanoi (including centering diphthongs ): Front and central vowels (i, ê, e, ư, â, ơ, ă, a) are unrounded , whereas the back vowels (u, ô, o) are rounded. The vowels â [ə] and ă [a] are pronounced very short, much shorter than the other vowels. Thus, ơ and â are basically pronounced

20440-712: The world. The Quaternary geology was developed through 5 cycles with the intercalation of marine and continental environments. The present Hạ Long Bay, in fact, appeared after the Middle Holocene maximum transgression, leaving ultimate zone of lateral undercutting in the limestone cliffs bearing many shells of oysters , having the 14C age as 2280 to >40,000 y. BP. Geological resources are abundant, including anthracite , petroleum, lignite , phosphate, oil shale , limestone and cement additives, kaolin , silica sand, dolomite , quartzite of exogenous origin, antimony , and mercury of hydrothermal origin. Additionally, there

20586-548: Was a coastal area unlike other Vietnamese cultures, for example, those found in Hòa Bình and Bắc Sơn . Located in Hạ Long and Cát Bà island its inhabitants developed to the level of sea exploitation. Cái Bèo culture is a link between Soi Nhụ culture and Hạ Long culture. Hạ Long Bay was the setting for historical naval battles against Vietnam's coastal neighbors. On three occasions, in the labyrinth of channels in Bạch Đằng River near

20732-494: Was borrowed) it was * r̝ , distinct at that time from * r . The following initial clusters occurred, with outcomes indicated: A large number of words were borrowed from Middle Chinese , forming part of the Sino-Vietnamese vocabulary . These caused the original introduction of the retroflex sounds /ʂ/ and /ʈ/ (modern s , tr ) into the language. Proto-Viet–Muong did not have tones. Tones developed later in some of

20878-620: Was first listed as a UNESCO World Heritage Site in 1994, in recognition of its outstanding, universal aesthetic value. In 2000, the World Heritage Committee additionally recognised Hạ Long Bay for its outstanding geological and geomorphological value, and its World Heritage Listing was updated. In October 2011, the World Monuments Fund included the bay on the 2012 World Monuments Watch , citing pressure from tourism and associated developments as threats to

21024-484: Was historically written using chữ Nôm , a logographic script using Chinese characters ( chữ Hán ) to represent Sino-Vietnamese vocabulary and some native Vietnamese words, together with many locally invented characters representing other words. Early linguistic work in the late 19th and early 20th centuries ( Logan 1852, Forbes 1881, Müller 1888, Kuhn 1889, Schmidt 1905, Przyluski 1924, and Benedict 1942) classified Vietnamese as belonging to

21170-416: Was likely deposited in pore space between grains, suggesting a high-energy depositional environment that removed carbonate mud. Recrystallized sparite is not diagnostic of depositional environment. Limestone outcrops are recognized in the field by their softness (calcite and aragonite both have a Mohs hardness of less than 4, well below common silicate minerals) and because limestone bubbles vigorously when

21316-837: Was separated from Viet–Muong around the 9th century, and evolved into Middle Vietnamese by 16th century. The sources for the reconstruction of Old Vietnamese are Nom texts, such as the 12th-century/1486 Buddhist scripture Phật thuyết Đại báo phụ mẫu ân trọng kinh ("Sūtra explained by the Buddha on the Great Repayment of the Heavy Debt to Parents"), old inscriptions, and a late 13th-century (possibly 1293) Annan Jishi glossary by Chinese diplomat Chen Fu (c. 1259 – 1309). Old Vietnamese used Chinese characters phonetically where each word, monosyllabic in Modern Vietnamese,

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