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CAVERN DIVE

CAVERN DIVE

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CAVERN DIVE

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  1. CAVERN DIVE PHOTO & DESIGN BY: CESAR VELASCO

  2. HOW THE CAVERNS WERE FORMED? • How caves are formed. Most caves are formed in limestone or in a related rock, such as marble or dolomite. Such caves, called solution caves, form as underground water slowly dissolves the rock. This process takes thousands of years. It begins when surface water trickles down through tiny cracks in the rock to a zone that is saturated with water. The topmost level of this saturated zone is called the water table. Water flowing above and below the water table dissolves some of the rock, forming passages, chambers, and pits. • Limestone and similar rock are only slightly soluble in water. But the water that trickles down from the surface contains carbon dioxide, which has been absorbed from the air and soil above the rock. The carbon dioxide forms a mild acid in the water, and this acid helps dissolve the rock. • Eventually, the water table may drop below the level of the cave. Or, the cave may be raised above the water table by a gradual uplifting of the ground. Most of the water then drains out, and air fills the cave. A surface stream may enter the cave and flow through it. The stream continues to dissolve the rock, enlarging the cave. Connections from the cave to the surface may develop in several ways. For example, the rock above part of the cave may collapse, forming a vertical entrance called a sinkhole. A horizontal entrance may develop on a hillside or a valley slope, especially at a point where a spring or stream flows from the cave.

  3. SPELEOTHEMS • Other types of caves include lava tubes and sea caves. Lava tubes form from molten lava. As lava flows down a slope, its outer surface cools and hardens, but the lava beneath remains molten. The molten lava continues to flow and eventually drains out, forming a cave. Lava caves lie near the surface of the earth and commonly have many openings in their thin roof. Sea caves form along rocky shores as the surf wears away weak areas of the rock. Inland, flowing water can carry rock away from weak areas of rock such as granite, forming caves. • Many other kinds of speleothems also form in caves. Drapery consists of thin sheets of rock that hang from the ceiling. Flowstone develops where a thin film of water flows over the walls and floor of a cave, depositing sheets of minerals. Gypsum flowers are delicate spiral crystals that sprout from porous rock. Helictites are strangely twisted cylinders that grow from the walls, ceiling, or floor of a cave, or from other formations. • Life in caves. Wall paintings, stone tools, and skeletal remains found in caves show that people lived there thousands of years ago. Today, many kinds of animals, including a small number of human beings, use caves as permanent shelters.

  4. STALACTITE & STALAGMITE • See CAVE DWELLERS. • Animals that live in caves include birds, crickets, lizards, raccoons, rats, salamanders, and spiders. Large numbers of bats roost in caves during the day and fly out at night to hunt for insects. The guano (manure) of bats provides food for the countless beetles, millipedes, flatworms, and other creatures that live in caves. • Various species of animals known as troglobites live in the dark innermost part of most caves, where there is no light, wind, or change in temperature and humidity. Such animals include certain beetles, fish, salamanders, and spiders. Most troglobites are blind and have a thin, colorless skin or shell. They rely on highly developed senses of smell and touch to make up for their lack of • Speleothems. After most of the water has drained from a cave, water may continue to seep in through cracks in the rock. This water often contains dissolved minerals. As it enters the cave, some of the minerals crystallize and are deposited as speleothems. Although speleothems are commonly white, they may be of many colors, depending on the minerals that form them. • The best-known kinds of speleothems are stalactites and stalagmites. Stalactites are iciclelike formations that hang from the ceiling of a cave. Stalagmites are pillars that rise from the floor. A stalactite and a stalagmite may join and form a column. See STALACTITE; STALAGMITE

  5. Green plants, such as ferns and mosses, may grow in the outer parts of caves, which receive some sunlight. Only fungi and other organisms that do not require light can live in the dark inner areas. Caving, also called spelunking, is an exciting but somewhat risky hobby. Individuals who wish to explore caves should always do so in groups headed by experienced leaders. Cavers use some of the techniques and equipment of mountain climbing. For example, they use sturdy ropes to climb up and down steep underground cliffs. In addition, cavers wear hardhats and rugged, heavy clothing for protection against jagged rocks and low temperatures. Cavers should always carry at least three sources of light--a headlamp attached to the hardhat plus two flashlights. Experienced cavers want a cave to be in the same condition after they explore it as it was before they entered it. Therefore, they neither damage nor remove anything they may find in the cave. Speleothems are fragile and, if broken, cannot be restored. In addition, many cave animals are extremely rare and can be easily harmed. Contributor: Louise D. Hose, Ph.D., Environmental Studies Program Director, Westminster College. • Many other kinds of speleothems also form in caves. Drapery consists of thin sheets of rock that hang from the ceiling. Flowstone develops where a thin film of water flows over the walls and floor of a cave, depositing sheets of minerals. Gypsum flowers are delicate spiral crystals that sprout from porous rock. Helictites are strangely twisted cylinders that grow from the walls, ceiling, or floor of a cave, or from other formations. • Life in caves. Wall paintings, stone tools, and skeletal remains found in caves show that people lived there thousands of years ago. Today, many kinds of animals, including a small number of human beings, use caves as permanent shelters. See CAVE DWELLERS. • Animals that live in caves include birds, crickets, lizards, raccoons, rats, salamanders, and spiders. Large numbers of bats roost in caves during the day and fly out at night to hunt for insects. The guano (manure) of bats provides food for the countless beetles, millipedes, flatworms, and other creatures that live in caves. • Various species of animals known as troglobites live in the dark innermost part of most caves, where there is no light, wind, or change in temperature and humidity. Such animals include certain beetles, fish, salamanders, and spiders. Most troglobites are blind and have a thin, colorless skin or shell. They rely on highly developed senses of smell and touch to make up for their lack of

  6. STALACTITE AND STALAGMITE Taylor, Michael R. Cave Passages: Roaming the Underground Wilderness. Scribner, 1996. ---- end of article ---- Stalactite, pronounced stuh LAK tyt or STAL uhk tyt, is a beautiful stone formation found in some limestone caves. Stalactites hang from the walls or roofs of the caves. Most look like large icicles, but some resemble draperies or straws with a hole through their center. Most stalactites form when ground water rich in carbon dioxide dissolves the mineral calcite (calcium carbonate) from limestone directly above the cave. As the water drips into the cave, it loses carbon dioxide to the cave atmosphere and leaves behind minute quantities of calcite. The calcite accumulates very slowly, forming stalactites. In many cases, this process occurs over thousands of years. Formations that build up from the floor of a cave are called stalagmites (see STALAGMITE). In the United States, excellent examples of stalactites and stalagmites exist in Carlsbad Caverns in New Mexico, Luray Caverns in Virginia, Mammoth Cave in Kentucky, Cumberland Caverns in Tennessee, and Blanchard Springs Caverns in Arkansas. See also CALCITE; CAVE. Contributor: Nicholas C. Crawford, Ph.D., Professor and Director, Center for Cave and Karst Studies, Western Kentucky University. ---- end of article ---- Stalagmite, pronounced stuh LAG myt or STAL uhg myt, is a stone formation that rises up from the floors of caves, especially in limestone caverns. Stalagmites form when water, dripping on the floor from the walls and roofs of the cave, carries with it deposits of calcium carbonate, or calcite. As the water enters the cave's atmosphere, it loses carbon dioxide and produces calcite. The calcite builds up into colorful stone formations that look like icicles upside down. Similar formations, which hang from the roof of the cave, are called stalactites (see STALACTITE). Sometimes stalagmites and stalactites join to form columns or stone curtains against the walls of the cave. See also CALCITE; CAVE. Contributor: Nicholas C. Crawford, Ph.D., Professor and Director, Center for Cave and Karst Studies, Western Kentucky University.

  7. Mayans and cenotes Cenotes come from the word DZONOT wich means in mayan lenguage- hole of fresh water -they were sacred to the Maya. The mayan used the cenotes for water - both for drinking and irrigation - and in religious ceremonies. Some of their cities were built around cenotes or wells dug down to the ground water. Divers have explored many cenotes and have found offerings the ancient Maya made to the gods. Among them copper and gold necklaces, pottery, jade beads, and skeletons of both sexes and all ages. Cenotes are beleived to have been of great significance to the Mayan people.  Recognized by the Maya as the link between the earth and the netherworlds (XIBALBA) and  often the only source of freshwater in the riverless Yucatan Penninsula,

  8. Cenotes  were considered sacred and important ceremonial centers were often constructed  nearby. Surrounded by dense jungle, cenotes are oases of cool clear fresh water, perfect  for cooling off in the heat of the day. Cenotes are the entrace to magical caverns and cave passages below the earth. • SACRIFICE Sacrifice  was a ritual in honor to their gods. There were many different ways to sacrifice: • Auto-sacrifice: an act in wich they used to bleed by cutting their tongue, ears and penis with an obsidian rock (volcanic glass) or stingrray spine. • Human sacrifice: was executed by taking the victims heart, cutting off the head and after tied up with a rock to trough the rests of the body in to the bottom of a cenote

  9. Chac mool • There are very common sculptures in Chichenitza. They represents the messanger of gods. They hold on their stomach a pot where used to deposit gifts