2. CONTENTS
2. Sinkholes
• Definition
• Description and Types
• Formation
• Images
• Revision sheet
3. Caves
•Definition
•Description
•Formation
•Types
•Difference (between cave and sinkhole)
•Images
•Revision sheet
1. Insight on Gaspar Grande and Gasparee Cave
3. GASPAR GRANDE
• Also known as Gasparee Island, it is a part of the "Bocas Islands", which lie
in the Bocas del Dragón (Dragon's Mouth) between Trinidad and
Venezuela.
• Gaspar Grande is primarily limestone, and is home to the Gasparee Caves, a
natural limestone cave system with a mysterious pool at its base.
• The cave is full of geological formations such as stalactites, stalagmites, flow
stones, pillars, ribbon, and fringed curtain.
Cropped shot of the north-west
coast of Trinidad.
Map of Gaspar Grande Island.
4. MY TRIP TO THE CAVE
• From the Chaguaramas jetty, a 3-4 minute boat ride over Paria Bay is required
to arrive to Gaspar Grande.
• Along the way, I observed sights of homes on other islands, oceanic creatures
and open skies.
• Upon arrival onto the island, a 10 minute inclined walk on paved sidewalks
pursed. I arrived at a building where I was briefed before entering the caves.
From the building, there was a balcony with a magnificent view of open sea.
--Then I entered the cave.
View of the jetty View from the briefing building
6. DESCRIPTION AND TYPES OF SINKHOLES
• Sinkholes are cylindrical or steep-sided
conical depressions that are generally formed
by the solution of limestone near the surface.
• Sinkholes may be many metres in diameter
and up to hundreds of metres deep. Their
colour and texture would depend on the type
of soil they occurred in (often sand and clay
soils), usually shades of brown and hard in
texture.
• Two main varieties:
1) Sinkholes caused by the collapse of the roof
of a cave/cavern.
2) 2) The gradual dissolving of rock under a
soil mantle resulting in a sinkhole.
8. FORMATION OF A SINKHOLE (CONTINUED)
• As the limestone dissolves,
pores/cracks are enlarged
and carry even more acidic
water.
• Sinkholes are formed when
the land surface above
collapses or sinks into
the dissolved cavities, for
example; a cave.
9. GASPAREE CAVE SINKHOLE
Image showing view of ground level
sinkhole from underground (inside
the cave).
Image showing sunlight passing
through the sinkhole, and into the
cave beneath it.
11. SINKHOLE REVISION SHEET
• Sinkholes are topographic depressions in a limestone
landscape of varying depths and sizes. They are also
known as swallow holes, cesspools or dolines.
• Sinkholes are formed when the land surface above
collapses or sinks into the dissolved cavities, for
example; a cave.
• Sinkholes are the open area above caves. Sinkholes
usually form when the roof of caves collapse due to
gravity.
12. CAVES
DEFINITION
•A hollow underground chamber with an
entrance at the surface, typically in a hillside or
cliff, caused by water erosion or volcanic action.
Caves are usually large enough to permit the
entry of man.
13. DESCRIPTION OF A CAVE
• A cave is a natural opening in the ground, usually
extending beyond the zone of light and large enough to
permit the entry of man.
• Occurring in a wide variety of rock types and caused by
widely differing geological processes.
• Caves range in size from single small rooms to
interconnecting passages many miles long.
• *A cavern is a large cave.
14. FORMATION OF A CAVE
Caves are formed by the dissolution of limestone.
Rainwater picks up carbon dioxide from the air and as it
percolates through the soil, which turns into a weak acid.
This slowly dissolves out the limestone along the joints,
bedding planes and fractures, some of which become
enlarged enough to form caves.
15. FOUR MAIN TYPES OF CAVES
• Solution Caves: These are formed in carbonate and sulfate rocks
such as limestone, marble, and gypsum. It is formed by the action of
slowly moving ground water that dissolves the rock to form tunnels,
irregular passages, and even large caverns along joints and bedding
planes.
• Lava Caves: These are tunnels or tubes in lava. It is formed when
the outer surface of a lava flow cools and hardens while the molten
lava within continues to flow and eventually drains out through the
newly formed tube.
• Sea Caves: These are formed by the constant action of waves which
attack the weaker portions of rocks lining the shores of oceans and
large lakes. Such caves testify to the enormous pressures exerted by
waves and to the corrosive power of wave-carried sand and gravel.
• Glacier Caves: These are caves formed within the ice of a glacier,
by melted water which excavates drainage tunnels through the ice.
16. DIFFERENCE BETWEEN SINKHOLES AND CAVES
• Sinkholes are the open area above
caves. Sinkholes usually form when the
roof of caves collapse due to gravity.
• Caves are the area formed below
sinkholes, usually from the dissolution
of carbonate rock over time by
naturally acidic rain and groundwater.
Sinkholes and caves may seem
similar, here’s how they differ:
17. GASPAREE CAVE
• The solutional cave was formed from water deposits of carbon dioxide
which dissolved the limestone into crystals of calcium bicarbonate.
• Over time, the accumulations of crystals created stalagmites, which extend
up from the cave floor, and stalactites they extend down from the roof of the
cave. Those that stem fully from the roof to the floor of the cave are called
pillars.
• Some of the crystals formed into fascinating shapes, appearing as a
dinosaur head, a chandelier, two lovers hugging and even flowers.
19. EXAMPLES OF OTHER CAVES
Reed Flute Cave, Southern China Waitomo Caves, New Zealand
Skocjan Caves, Europe Carlsbad Caverns, New Mexico
20. CAVES REVISION SHEET
• A cave is a natural opening in the ground,
usually extending beyond the zone of light and
large enough to permit the entry of man.
• They can occur when the rock below ground
level is limestone (or other carbonate rock) that
was dissolved naturally by circulating ground
water.
• Caverns are larger caves.
