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44-504: Moncks Cave is a cave located in Redcliffs , Christchurch , New Zealand. The cave was uncovered by road workers in 1889, and is considered to be one of the greatest archaelogical sites in New Zealand. It is notable for the evidence that it has provided of early Māori occupation. The cave was found in 1889 by workmen who were quarrying for road metal . The workmen cleared and dug through

88-438: A stratum , is the smallest formal unit in the hierarchy of sedimentary lithostratigraphic units and is lithologically distinguishable from other layers above and below. Customarily, only distinctive beds, i.e. key beds , marker beds , that are particularly useful for stratigraphic purposes are given proper names and considered formal lithostratigraphic units. In case of volcanic rocks, the lithostratigraphic unit equivalent to

132-415: A bed can be defined by thickness where a bed is a coherent layer of sedimentary rock, sediment, or pyroclastic material greater than 1 cm thick and a lamina is a coherent layer of sedimentary rock, sediment, or pyroclastic material less than 1 cm thick. This method of defining bed versus lamina is frequently used in textbooks, e.g., Collinson & Mountney or Miall. Both definitions have merit and

176-526: A bed is a flow . A flow is “...a discrete, extrusive, volcanic rock body distinguishable by texture, composition, order of superposition, paleomagnetism, or other objective criteria.” A flow is a part of a member as a bed of sedimentary rock is a part of a member. In geotechnical engineering a bedding surface often forms a discontinuity that may have a large influence on the mechanical behaviour (strength, deformation, etc.) of soil and rock masses in tunnel , foundation , or slope construction. These are

220-509: A combination of local deposition on the inclined surfaces of ripples or dunes , and local erosion . Graded beds show a gradual change in grain or clast sizes from one side of the bed to the other. A normal grading occurs where there are larger grain sizes on the older side, while an inverse grading occurs where there are smaller grain sizes on the older side. Bed thickness is a basic and important characteristic of beds. Besides mapping stratigraphic units and interpreting sedimentary facies,

264-426: A distinctive landform known as karst , characterized by sinkholes and underground drainage. Limestone caves are often adorned with calcium carbonate formations produced through slow precipitation . These include flowstones , stalactites , stalagmites , helictites , soda straws and columns. These secondary mineral deposits in caves are called speleothems . The portions of a solutional cave that are below

308-551: A hollow tube remains. Such caves can be found in the Canary Islands , Jeju-do , the basaltic plains of Eastern Idaho , and in other places. Kazumura Cave near Hilo , Hawaii is a remarkably long and deep lava tube; it is 65.6 km long (40.8 mi). Lava caves include but are not limited to lava tubes. Other caves formed through volcanic activity include rifts, lava molds, open vertical conduits, inflationary, blisters, among others. Sea caves are found along coasts around

352-420: A modern understanding of acoustics. Archaeologists have uncovered relationships between paintings of dots and lines, in specific areas of resonance, within the caves of Spain and France, as well as instruments depicting paleolithic motifs, indicators of musical events and rituals. Clusters of paintings were often found in areas with notable acoustics, sometimes even replicating the sounds of the animals depicted on

396-508: A pale or white coloration), a loss of eyes (or at least of optical functionality), an elongation of appendages, and an enhancement of other senses (such as the ability to sense vibrations in water). Aquatic troglobites (or stygobites), such as the endangered Alabama cave shrimp , live in bodies of water found in caves and get nutrients from detritus washed into their caves and from the feces of bats and other cave inhabitants. Other aquatic troglobites include cave fish, and cave salamanders such as

440-449: A range of early human species dating back to between three and one million years ago, including Australopithecus africanus , Australopithecus sediba and Paranthropus robustus . However, it is not generally thought that these early humans were living in the caves, but that they were brought into the caves by carnivores that had killed them. The first early hominid ever found in Africa,

484-406: A relatively short distance underground (such as rock shelters ). Caves which extend further underground than the opening is wide are called endogene caves . Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called caving , potholing , or spelunking . The formation and development of caves

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528-442: A result of changes in environmental conditions. As a result, a bed is typically, but not always, interpreted to represent a single period of time when sediments or pyroclastic material accumulated during uniform and steady paleoenvironmental conditions. However, some bedding surfaces may be postdepositional features either formed or enhanced by diagenetic processes or weathering . The relationship between bedding surfaces controls

572-415: A stream sinks"), outflow caves ("from which a stream emerges"), and through caves ("traversed by a stream"). Solutional caves or karst caves are the most frequently occurring caves. Such caves form in rock that is soluble; most occur in limestone , but they can also form in other rocks including chalk , dolomite , marble , salt, and gypsum . Except for salt caves , solutional caves result when rock

616-453: Is determined on the basis of the lower limit of karst forming processes, coinciding with the base of the soluble carbonate rocks. Most caves are formed in limestone by dissolution . Caves can be classified in various other ways as well, including a contrast between active and relict: active caves have water flowing through them; relict caves do not, though water may be retained in them. Types of active caves include inflow caves ("into which

660-444: Is dissolved by natural acid in groundwater that seeps through bedding planes , faults , joints, and comparable features. Over time cracks enlarge to become caves and cave systems. The largest and most abundant solutional caves are located in limestone. Limestone dissolves under the action of rainwater and groundwater charged with H 2 CO 3 ( carbonic acid ) and naturally occurring organic acids . The dissolution process produces

704-406: Is estimated that a cave cannot be more than 3,000 metres (9,800 ft) vertically beneath the surface due to the pressure of overlying rocks. This does not, however, impose a maximum depth for a cave which is measured from its highest entrance to its lowest point, as the amount of rock above the lowest point is dependent on the topography of the landscape above it. For karst caves the maximum depth

748-468: Is known as speleogenesis ; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorganisms, pressure, and atmospheric influences. Isotopic dating techniques can be applied to cave sediments, to determine the timescale of the geological events which formed and shaped present-day caves. It

792-625: The Denisovans in southern Siberia. In southern Africa, early modern humans regularly used sea caves as shelter starting about 180,000 years ago when they learned to exploit the sea for the first time. The oldest known site is PP13B at Pinnacle Point . This may have allowed rapid expansion of humans out of Africa and colonization of areas of the world such as Australia by 60–50,000 years ago. Throughout southern Africa, Australia, and Europe, early modern humans used caves and rock shelters as sites for rock art, such as those at Giant's Castle . Caves such as

836-777: The Madagascar dry deciduous forests and parts of Brazil contain many documented caves. As the world's expanses of soluble bedrock are researched by cavers, the distribution of documented caves is likely to shift. For example, China, despite containing around half the world's exposed limestone—more than 1,000,000 square kilometres (390,000 sq mi)—has relatively few documented caves. Cave-inhabiting animals are often categorized as troglobites (cave-limited species), troglophiles (species that can live their entire lives in caves, but also occur in other environments), trogloxenes (species that use caves, but cannot complete their life cycle fully in caves) and accidentals (animals not in one of

880-588: The Taung Child in 1924, was also thought for many years to come from a cave, where it had been deposited after being predated on by an eagle. However, this is now debated (Hopley et al., 2013; Am. J. Phys. Anthrop.). Caves do form in the dolomite of the Ghaap Plateau, including the Early, Middle and Later Stone Age site of Wonderwerk Cave ; however, the caves that form along the escarpment's edge, like that hypothesised for

924-532: The olm and the Texas blind salamander . Cave insects such as Oligaphorura (formerly Archaphorura) schoetti are troglophiles, reaching 1.7 millimetres (0.067 in) in length. They have extensive distribution and have been studied fairly widely. Most specimens are female, but a male specimen was collected from St Cuthberts Swallet in 1969. Bats , such as the gray bat and Mexican free-tailed bat , are trogloxenes and are often found in caves; they forage outside of

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968-456: The very slow flow of the ice, which tends to collapse the caves again. Glacier caves are sometimes misidentified as " ice caves ", though this latter term is properly reserved for bedrock caves that contain year-round ice formations. Fracture caves are formed when layers of more soluble minerals, such as gypsum, dissolve out from between layers of less soluble rock. These rocks fracture and collapse in blocks of stone. Talus caves are formed by

1012-480: The water table or the local level of the groundwater will be flooded. Lechuguilla Cave in New Mexico and nearby Carlsbad Cavern are now believed to be examples of another type of solutional cave. They were formed by H 2 S ( hydrogen sulfide ) gas rising from below, where reservoirs of oil give off sulfurous fumes. This gas mixes with groundwater and forms H 2 SO 4 ( sulfuric acid ). The acid then dissolves

1056-514: The yaodong in China were used for shelter; other caves were used for burials (such as rock-cut tombs ), or as religious sites (such as Buddhist caves ). Among the known sacred caves are China's Cave of a Thousand Buddhas and the sacred caves of Crete . Paleolithic cave paintings have been found throughout the world dating from 64,800 years old for non-figurative art and 43,900 years old for figurative art. The importance of sound in caves predates

1100-755: The Taung Child, are formed within a secondary limestone deposit called tufa . There is numerous evidence for other early human species inhabiting caves from at least one million years ago in different parts of the world, including Homo erectus in China at Zhoukoudian , Homo rhodesiensis in South Africa at the Cave of Hearths ( Makapansgat ), Homo neanderthalensis and Homo heidelbergensis in Europe at Archaeological Site of Atapuerca , Homo floresiensis in Indonesia, and

1144-533: The analysis of bed thickness can be used to recognize breaks in sedimentation, cyclic sedimentation patterns, and gradual environmental changes. Such sedimentological studies are typically based on the hypothesis that the thicknesses of stratigraphic units follows a log-normal distribution . Differing nomenclatures for the bed and laminae thickness have been proposed by various authors, including McKee and Weir, Ingram, and Reineck and Singh. However, none of them have been universally accepted by Earth scientists. In

1188-427: The base of the hill, which led to the discovery of the entrance to the cave. Large amounts of cockle shells were discovered when the cave was opened. The cave was most likely closed by a landslide that occurred before European settlement. The cave showed evidence of previous fires by the amount of charcoal found on the roof. One artefact found in the cave is a wooden ama , which is also known as an outrigger canoe . It

1232-578: The caves utilized for reverberation, but for the dampening qualities of their abnormal faces as well. The irregularities in the walls of the Cumberland Caverns diffuse sounds bouncing off the walls and give the space an almost recording studio-like quality. During the 20th century musicians began to explore the possibility of using caves as locations as clubs and concert halls, including the likes of Dinah Shore , Roy Acuff , and Benny Goodman . Unlike today, these early performances were typically held in

1276-561: The caves. Some species of cave crickets are classified as trogloxenes, because they roost in caves by day and forage above ground at night. Because of the fragility of cave ecosystems, and the fact that cave regions tend to be isolated from one another, caves harbor a number of endangered species, such as the Tooth cave spider , liphistius trapdoor spider , and the gray bat. Caves are visited by many surface-living animals, including humans. These are usually relatively short-lived incursions, due to

1320-422: The choice of which one to use will depend on the focus of the specific study on a case by case basis. Typically, but not always, bedding surfaces record changes in either the rate or type of accumulating sediment that created the underlying bed. Typically, they represent either a period of nondeposition, erosional truncation, shift in flow or sediment regime, abrupt change in composition, or combination of these as

1364-530: The gross geometry of a bed. Most commonly, the bottom and top surfaces of beds are subparallel to parallel to each other. However, some bedding surfaces of a bed are nonparallel, e.g., wavy, or curved. Differing combinations of nonparallel bedding surfaces results in beds of widely varying geometric shapes such as uniform-tabular, tabular-lenticular, curved-tabular, wedge-shaped, and irregular beds. Types of beds include cross-beds and graded beds . Cross-beds, or "sets," are not layered horizontally and are formed by

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1408-562: The lack of light and sustenance. Cave entrances often have typical florae. For instance, in the eastern temperate United States, cave entrances are most frequently (and often densely) populated by the bulblet fern, Cystopteris bulbifera . People have made use of caves throughout history. The earliest human fossils found in caves come from a series of caves near Krugersdorp and Mokopane in South Africa. The cave sites of Sterkfontein , Swartkrans , Kromdraai B, Drimolen , Malapa , Cooper's D, Gladysvale, Gondolin and Makapansgat have yielded

1452-413: The limestone from below, rather than from above, by acidic water percolating from the surface. Caves formed at the same time as the surrounding rock are called primary caves . Lava tubes are formed through volcanic activity and are the most common primary caves. As lava flows downhill, its surface cools and solidifies. Hot liquid lava continues to flow under that crust, and if most of it flows out,

1496-470: The many artefacts found in the cave, it is considered to be one of the greatest archaeological finds in New Zealand. In 2009, the cave was listed by Heritage New Zealand as a category 1 historic place. Cave A cave or cavern is a natural void under the Earth 's surface . Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend

1540-422: The mouths of the caves, as the lack of technology made depths of the interior inaccessible with musical equipment. In Luray Caverns , Virginia, a functioning organ has been developed that generates sound by mallets striking stalactites, each with a different pitch. Bedding planes Specifically in sedimentology , a bed can be defined in one of two major ways. First, Campbell and Reineck and Singh use

1584-465: The openings among large boulders that have fallen down into a random heap, often at the bases of cliffs. These unstable deposits are called talus or scree , and may be subject to frequent rockfalls and landslides . Anchialine caves are caves, usually coastal, containing a mixture of freshwater and saline water (usually sea water). They occur in many parts of the world, and often contain highly specialized and endemic fauna. Caves are found throughout

1628-710: The practice of engineering geology, a standardized nomenclature is used for describing bed thickness in Australia, the European Union, and the United Kingdom. Examples of widely used bed thickness classifications include Tucker (1982) and McKee and Weir (1953). According to both the North American Stratigraphic Code and International Stratigraphic Guide, a bed is the smallest formal lithostratigraphic unit that can be used for sedimentary rocks. A bed,

1672-428: The previous categories). Some authors use separate terminology for aquatic forms (for example, stygobites , stygophiles , and stygoxenes ). Of these animals, the troglobites are perhaps the most unusual organisms. Troglobitic species often show a number of characteristics, termed troglomorphic, associated with their adaptation to subterranean life. These characteristics may include a loss of pigment (often resulting in

1716-403: The term bed to refer to a thickness-independent layer comprising a coherent layer of sedimentary rock, sediment, or pyroclastic material bounded above and below by surfaces known as bedding planes. By this definition of bed, laminae are small beds that constitute the smallest (visible) layers of a hierarchical succession and often, but not always, internally comprise a bed. Alternatively,

1760-462: The walls. The human voice was also theorized to be used as an echolocation device to navigate darker areas of the caves where torches were less useful. Dots of red ochre are often found in spaces with the highest resonance, where the production of paintings was too difficult. Caves continue to provide usage for modern-day explorers of acoustics. Today Cumberland Caverns provides one of the best examples for modern musical usages of caves. Not only are

1804-417: The water, such as a fault or joint. A subtype of the erosional cave is the wind or aeolian cave, carved by wind-born sediments. Many caves formed initially by solutional processes often undergo a subsequent phase of erosional or vadose enlargement where active streams or rivers pass through them. Glacier caves are formed by melting ice and flowing water within and under glaciers. The cavities are influenced by

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1848-650: The world, although the distribution of documented cave system is heavily skewed towards those countries where caving has been popular for many years (such as France, Italy, Australia, the UK, the United States, etc.). As a result, explored caves are found widely in Europe, Asia, North America and Oceania, but are sparse in South America, Africa, and Antarctica. This is a rough generalization, as large expanses of North America and Asia contain no documented caves, whereas areas such as

1892-791: The world. A special case is littoral caves, which are formed by wave action in zones of weakness in sea cliffs. Often these weaknesses are faults, but they may also be dykes or bedding-plane contacts. Some wave-cut caves are now above sea level because of later uplift. Elsewhere, in places such as Thailand 's Phang Nga Bay , solutional caves have been flooded by the sea and are now subject to littoral erosion. Sea caves are generally around 5 to 50 metres (16 to 164 ft) in length, but may exceed 300 metres (980 ft). Corrasional or erosional caves are those that form entirely by erosion by flowing streams carrying rocks and other sediments. These can form in any type of rock, including hard rocks such as granite. Generally there must be some zone of weakness to guide

1936-402: Was found in 1889, in the same year as the cave's discovery. Other artefacts discovered include a carved paddle , a canoe bailer , a wooden carving of a dog, fragments of a fishing net , a number of greenstone axe, an amount of black hair and bones of fish and moa , which were found in another cave inside the main one. These artefacts have helped researchers learn about Māori culture . Due to

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