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Loss Of The Continuous Guideline
Cave-diving is underwater diving in water-filled caves. It may be done as an extreme sport, a way of exploring flooded caves for scientific investigation, or for the underwater search and recovery, search for and recovery of divers or, as in the Tham Luang cave rescue, 2018 Thai cave rescue, other cave users. The equipment used varies depending on the circumstances, and ranges from Free-diving, breath hold to Surface-supplied diving, surface supplied, but almost all cave-diving is done using scuba equipment, often in specialised configurations with engineering redundancy, redundancies such as Sidemount diving, sidemount or backmounted twinset. Recreational cave-diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves planned Decompression (diving), decompression stops. A distinction is made by recreational diver training agencies between cave-diving and cavern-diving, where cavern diving i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave Diver Running A Reel
Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend 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, ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves 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 sedime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scuba Skills
Scuba skills are skills required to dive safely using self-contained underwater breathing apparatus, known as a scuba set. Most of these skills are relevant to both open-circuit scuba and Rebreather diving, rebreather scuba, and many also apply to surface-supplied diving. Some scuba skills, which are critical to divers' safety, may require more practice than standard recreational training provides to achieve reliable competence. Some skills are generally accepted by recreational diver certification agencies as basic and necessary in order to dive without direct supervision. Others are more advanced, although some List of diver certification organizations, diver certification and accreditation organizations may require these to endorse entry-level competence. Instructors assess divers on these skills during basic and advanced training. Divers are expected to remain competent at their level of certification, either by practice or through refresher courses. Some certification organiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvation
Solvations describes the interaction of a solvent with dissolved molecules. Both ionized and uncharged molecules interact strongly with a solvent, and the strength and nature of this interaction influence many properties of the solute, including solubility, reactivity, and color, as well as influencing the properties of the solvent such as its viscosity and density. If the attractive forces between the solvent and solute particles are greater than the attractive forces holding the solute particles together, the solvent particles pull the solute particles apart and surround them. The surrounded solute particles then move away from the solid solute and out into the solution. Ions are surrounded by a concentric shell of solvent. Solvation is the process of reorganizing solvent and solute molecules into solvation complexes and involves bond formation, hydrogen bonding, and van der Waals forces. Solvation of a solute by water is called hydration. Solubility of solid compounds dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science), crystal forms of calcium carbonate . Limestone forms when these minerals Precipitation (chemistry), precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as 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 (rock), dolomite, a closely related rock, which contains a high percentage of the mineral Dolomite (mine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speleogenesis
Speleogenesis is the origin and development of caves, the primary process that determines essential features of the hydrogeology of karst and guides its evolution. It often deals with the development of caves through limestone, caused by the presence of water with carbon dioxide dissolved within it, producing carbonic acid which permits the dissociation of the calcium carbonate in the limestone. Limestone The majority of limestone caves are formed by calcium carbonate dissolution by the solvent action of meteoric waters circulating through the rock. In the presence of carbon dioxide saturated water, calcium carbonate reacts to form the soluble calcium bicarbonate. :CaCO3 + CO2 + H2O → Ca(HCO3)2 As meteoric waters precipitate they dissolve atmospheric carbon dioxide to form a dilute carbonic acid solution, which builds up in permeable fissures, bedding planes, joints, and faults within limestone rocks. The exposed limestone then reacts to become calcium bicarbonate whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planetary Surface
A planetary surface is where the solid or liquid material of certain types of astronomical objects contacts the atmosphere or outer space. Planetary surfaces are found on solid objects of planetary mass, including terrestrial planets (including Earth), dwarf planets, natural satellites, planetesimals and many other small Solar System body, small Solar System bodies (SSSBs). The study of planetary surfaces is a field of planetary geology known as surface geology, but also a focus on a number of fields including planetary cartography, topography, geomorphology, atmospheric sciences, and astronomy. Land (or ground) is the term given to non-liquid planetary surfaces. The term ''landing'' is used to describe the collision of an object with a planetary surface and is usually at a velocity in which the object can remain intact and remain attached. In planetary differentiation, differentiated bodies, the surface is where the crust meets the planetary boundary layer. Anything below this i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth
Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering Water distribution on Earth, 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is at least somewhat humid and covered by vegetation, while large Ice sheet, sheets of ice at Polar regions of Earth, Earth's polar polar desert, deserts retain more water than Earth's groundwater, lakes, rivers, and Water vapor#In Earth's atmosphere, atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth's outer core, Earth has a liquid outer core that generates a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stygofauna
Stygofauna are any fauna that live in groundwater systems or aquifers, such as caves, fissures and vugs. Stygofauna and troglofauna are the two types of subterranean fauna (based on life-history). Both are associated with subterranean environments – stygofauna are associated with water, and troglofauna with caves and spaces above the water table. Stygofauna can live within freshwater aquifers and within the pore spaces of limestone, calcrete or laterite, whilst larger animals can be found in cave waters and wells. Stygofaunal animals, like troglofauna, are divided into three groups based on their life history - stygophiles, stygoxenes, and stygobites. # Stygophiles inhabit both surface and subterranean aquatic environments, but are not necessarily restricted to either. # Stygoxenes are like stygophiles, except they are defined as accidental or occasional presence in subterranean waters. Stygophiles and stygoxenes may live for part of their lives in caves, but don't complete t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speleology
Speleology () is the scientific study of caves and other karst features, as well as their chemical composition, composition, structure, physical property, physical properties, history, ecology, and the processes by which they form (speleogenesis) and change over time (speleomorphology). The term ''speleology'' is also sometimes applied to the recreational activity of exploration, exploring caves, but this is more properly known as ''caving'', ''potholing'' (British English), or ''spelunking'' (United States and Canadian English). Speleology and caving are often connected, as the physical skills required for ''in situ'' study are the same. Speleology is a cross-disciplinary field that combines the knowledge of chemistry, biology, geology, physics, meteorology, and cartography to develop portraits of caves as complex, evolving systems. History Before modern speleology developed, John Beaumont (geologist), John Beaumont wrote detailed descriptions of some Mendip Hills, Mendip c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recreational Scuba Diving
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure and are considered to be " fun". Etymology The term ''recreation'' appears to have been used in English first in the late 14th century, first in the sense of "refreshment or curing of a sick person", and derived turn from Latin (''re'': "again", ''creare'': "to create, bring forth, beget"). Prerequisites to leisure People spend their time on activities of daily living, work, sleep, social duties and leisure, the latter time being free from prior commitments to physiologic or social needs, a prerequisite of recreation. Leisure has increased with increased longevity and, for many, with decreased hours spent for physical and economic survival, yet others argue that time pressure has increased for modern people, as they are committed to too ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caving
Caving, also known as spelunking (United States and Canada) and potholing (United Kingdom and Ireland), is the recreational pastime of exploring wild cave systems (as distinguished from show caves). In contrast, speleology is the scientific study of caves and the cave environment.Caving in New Zealand (from Te Ara: The Encyclopedia of New Zealand, Accessed 2012-11.) The challenges involved in caving vary according to the cave being visited; in addition to the total absence of light beyond the entrance, negotiating pitches, squeezes, and water hazards can be difficult. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overhead Environment
The underwater diving environment, or just diving environment is the natural or artificial surroundings in which a dive is done. It is usually underwater, but professional diving is sometimes done in other liquids. Underwater diving is the human practice of voluntarily descending below the surface of the water to interact with the surroundings, for various recreational or occupational reasons, but the concept of diving also legally extends to immersion in other liquids, and exposure to other hyperbaric pressurised environments. The diving environment is limited by accessibility and risk, but includes water and occasionally other liquids. Most underwater diving is done in the shallower coastal parts of the oceans, and inland bodies of fresh water, including lakes, dams, quarries, rivers, springs, flooded caves, reservoirs, tanks, swimming pools, and canals, but may also be done in large bore ducting and sewers, power station cooling systems, cargo and ballast tanks of ships, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
