CAVERN DIVE - PowerPoint PPT Presentation

About This Presentation
Title:

CAVERN DIVE

Description:

CAVERN DIVE PHOTO & DESIGN BY: CESAR VELASCO HOW THE CAVERNS WERE FORMED? How caves are formed. Most caves are formed in limestone or in a related rock, such as ... – PowerPoint PPT presentation

Number of Views:507
Avg rating:3.0/5.0
Slides: 10
Provided by: cesarv6
Category:
Tags: cavern | dive | beetles

less

Transcript and Presenter's Notes

Title: CAVERN DIVE


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
Write a Comment
User Comments (0)
About PowerShow.com