SEACAVES
Sea caves are formed by the force of the ocean (or in some cases, lakes) attacking the zones of weakness in coastal cliffs. The weak zone is usually a fault, or fractured zone formed during slippage. Another type of weak zone is formed where dissimilar types of rocks are interbedded and one is weaker than the other. Typically this is a dike, or intrusive vein of more easily eroded rock found within a stronger host rock. Yet a third instance (as in the case of the EC below) is in sedimentary rocks where a layer of softer rock is interbedded between harder layers.(1)
Sea caves occur on almost every cliffed headland or coast where the waves break directly on a rock cliff and are formed by mechanical erosion rather than the chemical solution process that is responsible for the majority of inland caves. Zones of weakness in the cliff give way under the force of the waves and are eroded out; these cavities are enlarged by the hydraulic pressure built up by each wave. Holes, commonly known as blowholes, may eventually be forced through the roof of the cave to allow the pressure created by each wave to be released as a jet of spray. The cave may begin as a very narrow crack into which waves can penetrate and exert tremendous force, cracking the rock from within by both the weight of the water and by compression of air. Sand and rock carried by waves produce additional erosive power on the cave's walls. (2)
(3) (4)
Occasionally some flowstone or small stalagmites are seen, formed much as in solution caves. Typically these occur in caves formed in sandstone, limestone, or sometimes even those in basalt. Sea caves are found all over the world, and may be one of the most numerous types of caves. The Greek islands are noted for the variety and beauty of their sea caves. Most sea caves are small in relation to other types. By far the majority of sea caves consist of a single passage or chamber.
Sea caves may be explored in several ways: with kayaks or other small boats; by swimming in; or (like in this case) by walking if the cave empties out at low tide. When entering a cave where the surf is active, it's best to study conditions carefully before entering. Remember that the power of waves and swell will be amplified in the cave interior! (1)
THE DRAPANOS SEACAVE
The existence of numerous caves is inextricably linked to the rugged topography of Crete. The area around Cape Drapanos has plenty of grottos, caves and also seacaves.
The underwater „elephant“ cave is a very famous one, which only can be accessed by experienced divers because of its entrance 10 meters below the waterline. It was discovered in 1999 by the snorkeler Manolis Efthymakis and was then showed in January 2000 in TV by the professional diver and filmmaker G. Tzanakis.
This EC will lead you to another interesting seacave very close by, which can be accessed by foot via a steep staircase hidden in the coastal cliffs of Drapanos.
The cave has been shaped in Mesozoic limestone, which is the predominent sedimentary rock in this region and gives you a good example about the forming elements and mechanisms of its formation.
The entrance of the cave area has 2m height, 2.5m width, starts about 2 meters above sea level and continues in a narrow rock path close to sea.(pic. above) Depending on the tide and wind, the path can be partially flooded and after some carved steps it ends in front of the cave entrance.
In the rockwall beside the path you can see and feel different results of erosion and the color of the ground varies as a matter of the composition of the different materials. The path ends on a small plateau (from where the pic. is made) and just in front of the entrance of the main part of the cave. From here you can estimate the size and the recognize the characteristics of the cave
The cave is about 20 meters in length and has an width of 15-20m. It irepresents the main room of the cave and, because of its morphology, it is partially filled with water. The depth of the room (under water surface) ranges from a few centimeters to 2 meters, while the ceiling height above the water surface reaches 10m in some points. At the roof of the cave you see some reddish stalactites, indicating aluminum and iron content in the rocks. In the water there are many big stalactites, which states that once the floor of the cave was not covered by water. The study of sediments (organic, clastic and chemical) shows with certainty that the cave in previous seasons was dry.
In order to log this EC, please send your answers to the following questions to the owner:
1. When you enter the cave through the narrow gate at the end of the steps, stop and take a look to your left. Describe the rock wall. What color does it have and how does the surface look like? is it sharp or smooth? Do you have an explanation for this?
2. Now go further on the narrow path towards the cave. There are a few steps before you reach the small plateau, what color do they have? What do you think why?
3. Standing on the plateau, you can look into the main cave. Describe the ground level below you. Is it dry or flooded?
In case of any doubts, you may contact the owner.
You do not have to wait for log permission, however if there are any problems with your answers, I will contact you.
Even photos are not longer requiired as a proof of your visit, they are more than welcome.
Happy hunting !
btw. EarthCaches can be honoured with a Favorite Point too.
Sources:
(1) http://www.goodearthgraphics.com/
(2) https://www.britannica.com/science/sea-cave
(3) https://www.alohavisitorguides.com/wp-content/uploads/2013/06/Sea-Cave-Review-2.jpg
(4) http://en.protothema.gr/