Презентация "Speleologists and Caves"
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Speleologists
and
Caves.
- Caves were probably prehistoric man’s first shelter and home . In Europe , Africa and Asia there are numerous places that confirm this , where we can see graffiti of animals , men and tools.
- In some of these caves bones and skulls have been found belonging to the species homo.
- How are caves formed ? Mainly by the action of water and glaciers , over thousands of years, and the changes caused by the erosion, fracture and corrosion of the earth’s surface. Together these agents have created a wonderful underground world .
- It is surprising and mysterious , with its astonishing, multicolored stalactites and stalagmites, lakes and rivers whose waters are refreshingly pure.
- Speleologist , the scientific study of caves, is becoming ever more popular, as fascinating new discoveries are made in this field.
- Man started studying caves long ago , around 1700 but it is only in this century that speleologist has really become a branch of scientific investigation. ”Pot-holing” (exploring deep holes worn in rock) is best carried out by teams of experts who study the kind of rock in question, how a particular cave was formed, erosion caused by water, and any animal and plant life there is to be found.
- Lately, speleologists have begun anew kind of experiment; they are studying how the human body and mind react to staying under ground for lengthy periods. Everything is carefully monitored; blood pressure, heartbeat, cerebral activity, and the influence on man’s behavior.
- Elin Igor ,11a form