The Geology of Malta consists of a sequence of sedimentary rocks of late Oligocene to late Miocene age cut through by a set of extensional faults of Pliocene age.
The Maltese archipelago, situated between Sicily and Tunisia, was created through the uplift of sedimentary rocks. This uplift dates from the late Miocene to the Pliocene. Malta forms the crest of a tilted block on the edge of the Malta Graben. The isle of Lampedusa is made up of an identical structure on the southwest side of this rift.
The rocks are exclusively sedimentary. There is a lot of limestone, which has contributed to the construction of the ancient buildings of the island. These rocks come from marine deposits (essentially from lagoons) dating from between 25 and 5 million years ago.
The stratigraphy of the Maltese islands consists of five geological formations, ranging in age from late Oligocene to late Miocene
Limestone is a common type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3). Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils, and these provide scientists with information on ancient environments and on the evolution of life
Limestone may occur in different colours, depending on admixtures:
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COLOUR OF LIMESTONE
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ADMIXTURE
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yellow
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sulphur
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pink to dark reddish tints (terracotta)
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iron oxide
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blue, dark purple, grey
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manganese
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white
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lack of cement, the sandstone is usually brittle
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There are basically two colour of limestone: Yellow and White. Nature has carved in it amazing landforms, like rock arches, caverns, mushroom rocks and tafoni.
Mushroom rock may be formed in three ways:
- non-uniform erosion and weathering - hard mass of limestone capstone resisted erosion while the underlying softer stone weathered away,
- glacial action - a type of balancing rock. Mushroom is formed from two separate rocks, one of which came to rest on top of the other. Typically, the uppermost rock was transported and deposited by the slow action of a glacier,
- rock disturbance - forms from two rocks, one of which came to rest on the top of the other, caused by a very sudden disturbance such as a rock fall or earthquakes.
Conditions required for logging:
To log this cache you need to visit specific place with “Mushrooms” on coastline, answers the following questions and reply me to an email in my profile.:
1) How many mushroom rocks can you see from the given coordinates?
2) What is the height of tallest mushroom you can see?
3) Can you observe different layers in the mushroom? What is the difference in colour?
4) What is the hardness of the different layers? Try them by touching with your nail. Is it possible to scratch the different layers?
5) Can you see fossils in the mushroom rock? What is their shape?
6) Is the mushroom rock attached to the rock underneath it? How do you think these mushroom rocks were formed?
7) What animal does the limestones mushroom remind you? on stage 1
8) Please post a photo of yourself, or GPS with mushrooms.
Feel free to log this cache. You do not need to wait for permission to log. If your answers are not correct, incomplete, I will contact you by e-mail. But if your e-mail is not coming to me within 3 days from your log, I will delete your log without notice
Kundizzjonijiet meħtieġa għall-illoggjar:
Biex tilloggja din il-cache trid iżżur post speċifiku bil-“Faqqiegħ” fuq il-kosta, twieġeb il-mistoqsijiet li ġejjin u twieġeb email fil-profil tiegħi.:
1) Kemm-il blat tal-faqqiegħ tista' tara mill-koordinati mogħtija?
2) X'inhu l-għoli tal-faqqiegħ għoli li tista' tara?
3) Tista 'tosserva saffi differenti fil-faqqiegħ? X'inhi d-differenza fil-kulur?
4) X'inhi l-ebusija tas-saffi differenti? Ipprovahom billi tmiss bid-dwiefer tiegħek. Huwa possibbli li tobrox is-saffi differenti?
5) Tista' tara fossili fil-blat tal-faqqiegħ? X'inhi l-forma tagħhom?
6) Il-blat tal-faqqiegħ huwa mwaħħal mal-blat taħtu? Kif taħseb li ġew iffurmati dawn il-blat tal-faqqiegħ?
7) Liema annimal ifakkarkom il-faqqiegħ tal-franka? fuq l-istadju 1
8) Jekk jogħġbok ipoġġi ritratt tiegħek, jew GPS bil-faqqiegħ.
Ħossok liberu li tilloggja din il-cache. M'għandekx bżonn tistenna l-permess biex tilloggja. Jekk it-tweġibiet tiegħek mhumiex korretti, mhux kompluti, nikkuntattjak bl-e-mail. Imma jekk l-e-mail tiegħek ma tiġix għandi fi żmien 3 ijiem mill-log tiegħek, se nħassar il-log tiegħek mingħajr avviż
