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Echo Caves
The Echo Caves in Limpopo, South Africa, are set in Precambrian dolomite rock, which was first laid down about 3800 million years ago, when Africa was still part of Gondwana. The caves are considered some of the oldest in the world. The Echo Caves are about 92 km north of the similar Sudwala Caves. There are a number of speleothem structures in the cave; two of these are hollow stalactites which when hammered create echoes audible throughout and even outside the caves, thus the name of the caves. The caves are over 40 km long; regular tours are available for about 2 km of the tunnels and chambers. The caves were used for shelter in recent centuries by the Pedi people; they slept in what is now called the Samson chamber (due to the limestone columns which appear to hold the low roof of the cave up). History In the nineteenth century the Pedi lived in the Echo Caves. They used the hollow stalactites as a warning system to warn their people of attacks by neigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echo Caves Bat
In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room. A true echo is a single reflection of the sound source. The word ''echo'' derives from the Greek ἠχώ (''ēchō''), itself from ἦχος (''ēchos''), "sound". Echo in the Greek folk story is a mountain nymph whose ability to speak was cursed, leaving her able only to repeat the last words spoken to her. Some animals use echo for location sensing and navigation, such as cetaceans (dolphins and whales) and bats in a process known as echolocation. Echoes are also the basis of Sonar technology. Acoustic phenomenon Acoustic waves are reflected by walls or other hard surfaces, such as mountains and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echo Caves Samson Chamber
In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room. A true echo is a single reflection of the sound source. The word ''echo'' derives from the Greek ἠχώ (''ēchō''), itself from ἦχος (''ēchos''), "sound". Echo in the Greek folk story is a mountain nymph whose ability to speak was cursed, leaving her able only to repeat the last words spoken to her. Some animals use echo for location sensing and navigation, such as cetaceans (dolphins and whales) and bats in a process known as echolocation. Echoes are also the basis of Sonar technology. Acoustic phenomenon Acoustic waves are reflected by walls or other hard surfaces, such as mountains and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echo Caves Madonna Chamber
In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room. A true echo is a single reflection of the sound source. The word ''echo'' derives from the Greek ἠχώ (''ēchō''), itself from ἦχος (''ēchos''), "sound". Echo in the Greek folk story is a mountain nymph whose ability to speak was cursed, leaving her able only to repeat the last words spoken to her. Some animals use echo for location sensing and navigation, such as cetaceans (dolphins and whales) and bats in a process known as echolocation. Echoes are also the basis of Sonar technology. Acoustic phenomenon Acoustic waves are reflected by walls or other hard surfaces, such as mountains and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echo Caves Madonna Chamber 2
In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room. A true echo is a single reflection of the sound source. The word ''echo'' derives from the Greek ἠχώ (''ēchō''), itself from ἦχος (''ēchos''), "sound". Echo in the Greek folk story is a mountain nymph whose ability to speak was cursed, leaving her able only to repeat the last words spoken to her. Some animals use echo for location sensing and navigation, such as cetaceans (dolphins and whales) and bats in a process known as echolocation. Echoes are also the basis of Sonar technology. Acoustic phenomenon Acoustic waves are reflected by walls or other hard surfaces, such as mountains and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limpopo
Limpopo is the northernmost province of South Africa. It is named after the Limpopo River, which forms the province's western and northern borders. The capital and largest city in the province is Polokwane, while the provincial legislature is situated in Lebowakgomo. The province is made up of 3 former homelands of Lebowa, Gazankulu and Venda and the former parts of the Transvaal province. The Limpopo province was established as one of the new nine provinces after South Africa's first democratic election on the 27th of April 1994. The province's name was first "Northern Transvaal", later changed to "Northern Province" on the 28th of June 1995, together with two other provinces. The name was later changed again in 2002 to the Limpopo province. Limpopo is made up of 3 main ethnic groups namely; Pedi people, Tsonga and Venda people. Traditional leaders and chiefs still form a strong backbone of the province's political landscape. Established in terms of the Limpopo House of Tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countries of Namibia, Botswana, and Zimbabwe; and to the east and northeast by Mozambique and Eswatini. It also completely enclaves the country Lesotho. It is the southernmost country on the mainland of the Old World, and the second-most populous country located entirely south of the equator, after Tanzania. South Africa is a biodiversity hotspot, with unique biomes, plant and animal life. With over 60 million people, the country is the world's 24th-most populous nation and covers an area of . South Africa has three capital cities, with the executive, judicial and legislative branches of government based in Pretoria, Bloemfontein, and Cape Town respectively. The largest city is Johannesburg. About 80% of the population are Black South Afri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precambrian
The Precambrian (or Pre-Cambrian, sometimes abbreviated pꞒ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic Eon, which is named after Cambria, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean, Archean, Proterozoic) of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago ( Ga) to the beginning of the Cambrian Period, about million years ago ( Ma), when hard-shelled creatures first appeared in abundance. Overview Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history, and what is known has largely been discovered from the 1960s onwards. The Precambrian fossil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomite (rock)
Dolomite (also known as dolomite rock, dolostone or dolomitic rock) is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite, CaMg(CO3)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). The first geologist to distinguish dolomite rock from limestone was Belsazar Hacquet in 1778. Most dolomite was formed as a magnesium replacement of limestone or of lime mud before lithification. The geological process of conversion of calcite to dolomite is known as dolomitization and any intermediate product is known as dolomitic limestone. The "dolomite problem" refers to 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 ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages of break-up, involving the separation of Antarctica from South America (forming the Drake Passage) and Australia, occurred during the Paleogene. Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of Baltica, Laurentia, and Siberia were separated from it. To differentiate it from the Indian region of the same name (see ), it is also commonly called Gondwanaland. Gondwana was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Palaeozoic Era, covering an area of about , about one-fifth of the Earth's surface. During the Carboniferous Period, it merged with Laurasia to form a larger supercontinent called Pangaea. Gondwana (and Pan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sudwala Caves
The Sudwala Caves in Mpumalanga, South Africa, are set in Precambrian dolomite rock, which was first laid down about 2800 million years ago. The caves themselves formed about 240 million years ago. They are the oldest caves in the world. There are a number of speleothem structures in the cave, known by names such as the "Lowveld Rocket", "Samson's Pillar", and the "Screaming Monster"; some have been dated to 200 million years old. There are also microbial fossils of a cyanobacterium known as ''collenia'' in the rock; these formed 2000 million years ago. The caves were used for shelter in prehistoric times, probably due in part to a constant supply of fresh air from an unknown source in the caves. History Creation and early inhabitants The Sudwala Caves are the oldest known caves in the world, and began to form around 240 million years ago. Their formation was caused when natural acid in the groundwater seeped through the faults and joints of the Precambrian dolomite roc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speleothem
A speleothem (; ) is a geological formation by mineral deposits that accumulate over time in natural caves. Speleothems most commonly form in calcareous caves due to carbonate dissolution reactions. They can take a variety of forms, depending on their depositional history and environment. Their chemical composition, gradual growth, and preservation in caves make them useful paleoclimatic proxies. Chemical and physical characteristics More than 300 variations of cave mineral deposits have been identified. The vast majority of speleothems are calcareous, composed of calcium carbonate (CaCO3) minerals (calcite or aragonite). Less commonly, speleothems are made of calcium sulfate (gypsum or mirabilite) or opal. Speleothems of pure calcium carbonate or calcium sulfate are translucent and colorless. The presence of iron oxide or copper provides a reddish brown color. The presence of manganese oxide can create darker colors such as black or dark brown. Speleothems can also be brown d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedi People
The Pedi or (also known as the Northern Sotho or and the Marota or ) – are a Southern Africa, southern African ethnic group that speak Pedi or ''Sepedi'', a dialect belonging to the Sotho-Tswana peoples, Sotho-Tswana Ethnolinguistic group, enthnolinguistic group. Northern Sotho is a term used to refer to one of South Africa's 11 official languages. Northern Sotho or Sesotho sa Leboa consist of 33 dialects, of which Pedi is one of them. The BaPedi people are almost exclusively found in South Africa's Points of the compass, northeastern Provinces of South Africa, provinces which are Limpopo, and parts of northern Mpumalanga. There is confusion regarding the distinction between BaPedi people, and tribes referred to Northern Sotho (''Basotho ba Lebowa).'' On the one hand, one military explanation is that the BaPedi people became powerful at one point under a powerful king that ruled over a large piece of land. During this period, a powerful army of the BaPedi conquered small ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
