Bacaetava
A word from Tupi-Guarani origin meaning "holed stone house"
The cave was discovered 150 years ago by Italian immigrants and served as a hiding place for several families during the period of World War II.
The Municipal Park Gruta do Bacaetava has an area of 173 thousand square meters and houses a cave full of stalactites, stalagmites, columns, escorrimentos, pearls, travertines and corals.
The 700-million-year-old cave is 695 meters long, amidst the region's rocky metadolomite massif (Capiru Formation), featuring two levels of galleries with 25m of vertical unevenness
It is located in the geological unit of the Ribeira Mobile Belt, this belt is composed mainly of deformed rocks of different metamorphic grades belonging to the Açungui Group.
Visits: Wednesday to Friday from 8h30 to 11h30 and from 13h to 16h30. On Saturdays, Sundays and holidays from 8h30 to 16h30
Speleology
It is a science associated with geology that deals with the quest, observation and study of caves and caves. It is associated with the genesis, understanding of the internal and external environment and the constitution of these formations.
There are several definitions of cave. According to the International Union of Speleology, for example, a cave would be the natural opening formed in rock below the surface of the terrain, wide enough for man's entrance.
The caves (from the Latin cavus, hole) are natural formations that tend to occur in the so-called karstic terrains, constituted by rocks of soluble behavior. These rocks are those of the carbonate type, which have high rates of chemical solubility. One of the most common examples is limestone, one of the most known and abundant carbonate rocks.
When water penetrates and cracks through the cracks of these rocks, it dissolves its walls and generates larger and larger openings. Over the years, these fractures become large galleries. That is why, as you can confirm here in this cave, the ground is damp and will always have a trickle sound in the background.
Calcareous rocks are mainly composed of calcite (CaCO3), magnesite (MgCO3) and dolomite (CaMg (CO3) 2), all of which are carbonate minerals. The water itself is not enough to dissolve these minerals. However, if water becomes carbonic acid (ie has carbon dioxide amounts), it can easily dissolve calcium carbonate (CaCO3). Water can be enriched in CO2 by assimilating it from the atmosphere or from plant roots and decomposing organic material.
After these large galleries are formed, the water ends up enriched in (bi) calcium carbonate, as the rock dissolves its composition in it.
(Reaction of the dissolution of rocks rich in calcium carbonate. The result is water enriched in calcium bicarbonate)
Over time, in the drip, recrystallization of water enriched in calcium carbonate begins. That is to say: it returns to be rock. Does this remind you of any characteristic shape of caves? Something shaped like a drop, or cone, hanging from the roofs of natural galleries?
That's right: stalactites!
This dripping process that generates stalactites can take thousands of years, but it does not stop there. The drops that fall from the stalactites and fall on the floor of the caves also precipitate, forming structures very similar to the first ones: stalagmites. In format, they are identical! The difference is that stalagmites go from floor to ceiling, unlike stalactites! If the two grow too much, they end up together and form columns.
These and other structures are called speleothems, defined as rocky structures originating from the dissolution and recrystallization at lower levels of the ceiling, walls and floor of the caves
If you have visited this site and read the description correctly you can log on to Earthcache, send the responses via Message this owner, if they are not correct I will contact you
Questions:
1 - How are the characteristic caves and speleothems formed?
The shapes of the speleothems, which are thousands of years old, stir the visitor's imagination and often resemble objects and images. Observing the place and with information passed on by the guide that will accompany you on the tour, answer:
2 - Why should not we play the speleothems?
3 - What objects can we associate with some of the speleothems of the visited cave?
The Cave of the Bacaetava, suffered for several years a process of degradation by the visitation without control and by the activity of the miners. This process has caused several environmental problems inside the cavity such as: breakage of speleothems, gravel, sedimentation of underground drainage and accumulation of sterile material from the mines that deposit their tailings directly on the Bacaetava river.
4- Looking at the region at the end of the cave, can you see any result of this degradation?
5- A photo, or rather a lot of photos would be great (optional)