B. Psiloritis karstic lansdcapes
Karstic landscapes are very special areas on the Earth with a unique relief, often with a rough and rocky surface and a lack of both water and soil. The environment and the ecotopes are usually also unique and special, just like the species that they host. Thus both surface-structures such as plateaus, dolines, sinkholes and other similar structures, as well as underground ones like caves and potholes catch both the visitor’s eye and interest because they are both unique and individual.
In the Psiloritis mountains and especially at the higher zone, the dissolution of limestone, dolomite and marble has created a large number of karstic features and landscapes characterizing the scenery of the mountain and thus guiding life in all of its variety: from the very little beetle to man itself.
The “Karstic landscapes of Psiloritis”, except for the caves that occur everywhere in the park, is comprised of small surface cavities, sinkholes and potholes, as well as larger depressions like the dolines and plateaus of the Nida and Petradolakia areas.
In many places the absolute lack of soil and domination of limestone rock create impressive and weird sceneries. The craters in the Kourouna and Skinakas areas have given rise to many fantastic myths concerning the “volcanoes of Psiloritis”.
In the “Karstic landscapes of Psiloritis” visitors will meet all of these strange structures and will be captivated by the unique landscape and variety of life.
Nida is the highest plateau in Crete with a mean altitude of 1360 meters. It was formed as a result of karstic erosion, by the enlargement of smaller surface depressions (dolines), and now forms a larger structure, a polge. Like the nearby Petradolakia dolines, it occurs just at the place where the “Tripolitsa” limestone comes into contact with the underlying “Plattenkalk” rocks. The occurrence of thin “Plattenkalk” metaflysch and “Phyllite-Quartzite” rocks retained water for a longer time to form these depressions.
Τhe large Nida fault that delimits the eastern slopes of Psiloritis and the plateau itself played a significant role in the creation of Nida. The fault forced down the area of the plateau in respect to the Psiloritis summits, thus modulating conditions for water concentration and for the intense erosion of the rocks. Indeed the entrance to the Idaion Andron occurs exactly on the fault plane, which is also the cause of its discovery. Additionally, many sinkholes appear at the northern part of the plateau, which seems to have sunk even more, forcing surface water into the underground rivers.
The appearance of Nida changes depending upon the season. Either snow- or cloud-covered in winter, full green with small shrubs and wild flowers in spring, or painted red by the Cretan Maple in summer, or just gray with the barren rock in autumn, Nida always fascinate the senses.
Today, the raising of live stock mainly occurs in the plateau, but several decades ago the red soil was a fertile land for growing cereals. The existence of water, even on a small scale, is sufficient to maintain the ecosystems and human activities. The most important springs are those of Varsamos at the southern edge, Afenti Christou just near the Idaion Andron, and Romanas a bit further to the north.
In the countless nooks and crannies of the plateau, several mitata of the shepherds add a subtle brush stroke to the virgin landscape of the mountain.
Following the ravines that begin or end in the plateau, the traveler can climb up to the peak of Psiloritis, go down to the Rouvas forest, or behold in wonder the Mesara plain, from the natural balcony of the plain.
The Idaion Andron cave is located at the western edge of the Nida plateau, exactly on the steep cliff formed by the Nida fault. Its entrance is to be found on the fault plane, while internal parallel faults can also be seen. Nice folds of the platy marble occur both at the entrance and at the large internal area.
The cave is not particularly important from the geological point of view as it is relatively small and lacks speleothems, but it has a tremendous archaeological and cultural value. According to Greek mythology, it is the place where the Cretan-born Zeus (the king of the ancient Greek gods) was hidden by his mother to save him from the rage of his father, Cronos. The Curetes (Kourites), the local warriors masked the baby’s crying with their noise, while Amalthea, a goat with gold horns, nursed him with her milk. Archaeological excavations by Prof. I. Sakelarakis have revealed a great number of golden, iron and other finds proving that the Idaion Andron was the largest place of worship on Crete from the Minoan until the Roman era. Even today, the rocky, carved altar of antiquity still dominates the entrance to the cave.
A rare and somewhat weird landscape can be seen in the Petradolakia area, dominated by limestone and dolomites of the “Tripolitsa” group. Small and larger dolines, sinkholes and potholes, resembling volcanic craters, can be viewed all around from the nearby Skinakas peak, where the University Observatory is located.
Nice folds bend the multicolored, platy marble at the western part, whereas, white silica concretions appear in many places, formed, according to some studies, from sponge colonies on Tethys’ sea-bottom.
The rare soil of the plateaus host many typical species of Psiloritis’ flora and fauna. The most impressive are the very rare Horstrissea dolinicola (one of the four endemic genera of Greece) which grows only in small dolines around Skinakas, and the butterfly Cretan Argus (Kretania psylorita) which in spring flits about in the small plateaus of the Psiloritis mountains.
Β4.Τhe Cretan Detachment fault
Probably the best place to observe the Cretan Detachment fault is in the area around the Agios Fanourios chapel. This fault separates the metamorphosed rocks of the “Plattenklalk” and “Phyllite-quartzite” groups from the non-metamorphosed rocks of “Tripolitsa” occurring on top. Several million years ago this fault raised the rocks of the “Plattenkalk” group up to the surface, from a depth of 30 to 40 kms.
Indeed it is because of this fault that the nearby spring occurs. The fault brings into contact the limestone of the “Tripolitsa” group with the impermeable rocks of “Plattenkalk” metaflysch at the bottom, thus trapping rain water to form a spring. On the vertical limestone cliffs the famous Cretan Dittany or “erontas” (Origanum dictamnus) grows.
One of the less developed rocks on Mount Psiloritis, and on Crete in general, is the “Plattenkalk” metaflysch, an argillaceous and limestone cobbled schist, which has great importance for life on the mountain. It is the main reason for the appearance of a spring on the eastern part of Psiloritis mountains, as it traps the water sunk into the overlying “Tripolitsa” rocks. One of the largest exposures of metaflysch occurs in the Agia Marina area, near to the settlement of Zominthos, where it also forms several springs.
Migia’s gorge is a place connected with many traditions and folklore of the nearby village of Anogia. It develops within the platy marble of the “Plattenkalk” group, a rock type marvelously exposed, with repeated, zigzag or open folds, at the very steep, southern cliffs of the gorge. The gorge is only narrow at its beginning and end, but it is very deep and steep in many places.
A trail along the northern slope wanders through old and new mitata and shepherds farms, connecting gorges with many other geotopes of the area. (see the hiking trail)
Along the length of the road from Anogia to Nida, in the area of Stefana, dramatic folds appear with the shape N within the conventional platy marble. These folds are some of the largest in this area and characteristically appear both at the edge of the road and in the relief of the surrounding hills.
The role of water in sculpturing and shaping the landscape of Mount Psiloritis appears very characteristically in one of the most representative plateaus, that of Stefana. It can easily be approached by the road leading to Nida and it offers many opportunities for both wandering around and for visiting Migias’ gorge.
This small plateau is usually covered by small lakes that are formed due to the argillaceous soil where many amphibians (such as frogs) live. Several sinkholes occur in the centre and the northern side, near the road, from where water sinks into the platy marble. Many wild flowers, like crocuses (Crocus oreocreticus), Cretan colchicums (Colchicum cretense), and “Venus’ looking glass” (Legousia sp) and other typical plants of the area grow at different seasons.
From the small mitato located at the north of the plateau, with the typical yard for the milking of the sheep, one can walk towards the large Kermes Oak (Quercus coccifera) of the area, where a magnificent panorama of the northern part of the Park awaits the visitor as does a lovely sunset behind the Akrotiri of Chania in the evening.
Driving from Petradolakia to Skinakas summit there is a great chance to see a typical pothole of the Psiloritis area very close up indeed. A small trail crosses the dolomitic and limestone “desert” of “Tripolitsa” group, and through a small stream, enters into the pothole depression. The pothole itself is about 20 meters deep, ending in a very narrow and inaccessible cave. The breathtaking vertical sides of the pothole host a great variety of plants and nests, while snow can remain at its bottom even in mid summer.
Kourouna, a northern peak on the central mountain range of Psiloritis, is formed from conventional platy marble, which because of the horizontal layers, looks like a child’s pile of bricks. Its great altitude prevents vegetation and this results in well demonstrating all the forms of karstic surface erosion.
Many small dolines have been formed as craters, which can only be viewed from the Psiloritis summit, or partly, from the Livadia and Zoniana pasturelands.