Geology and Early Human History of the islands of Malta ...earthscienceindia.info/popular archival/download.php?file=pdf-59.pdf · hunters or farmers. Evidence of prehistoric farming

Open Access e‐Journal Earth Science India‐ www.earthscienceindia.info Popular Issue, VII (IV), October, 2014, p. 1‐13

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Geology and Early Human History of the islands of Malta, Mediterranean Sea

Arun Kumar

Geologically the Maltese Islands are young, primarily composed of marine sedimentary rocks, and the oldest rock formation dates back to the Tertiary Period…………..Archaeological evidences these islands were first settled in 5200 BC by Stone Age hunters or farmers. Evidence of prehistoric farming settlements of Early Neolithic period were found in open areas as well as in the caves like Għar Dalam. These early people in Malta grew cereals and raised domestic livestock.

Since I joined Sirte Oil Company in Libya in December 2013, I frequently travel between my work place in Brega, Libya and my home in Ottawa, Canada. During these travels I visited various European countries, and I especially found fascinating the island Republic of Malta. This country is commonly known as Malta, is located almost in the center of the Mediterranean Sea (Figure 1), 80 km south of Sicily, 333 km north of Libya and 284 km east of Tunisia. Thus it is along the important shipping routes in the Mediterranean Sea. During the long course of its history Malta was colonized by the Romans, French, Spanish, Arabs, Turks and the British. Malta gained independence from the United Kingdom in 1964 and became a republic in 1974 (Abela, 2014). The country was admitted to the United Nations in 1964 and to the European Union in 2004; in 2008, it became part of the Eurozone (Website 1).

Malta comprises of an archipelago of seven islands in the Mediterranean Sea, the main ones are Malta, Gozo and Comino (Figure 2). Its total area is 316 square km making it one of the world's smallest and most densely populated countries. The city of Valletta is the capital which covers an area merely of 0.8 square kilometer (Figure 3), the smallest capital in the European Union. Malta is a popular tourist destination with its warm climate, numerous recreational areas, and architectural and historical monuments, beautiful churches (Figure 4) including nine UNESCO World Heritage Sites and seven Megalithic Temples, which are some of the oldest free-standing structures in the world (Website 1).

GEOLOGY OF MALTA

The Maltese Islands lie on the Malta plateau, which is a shallow shelf formed over the

high points of a sub-oceanic ridge between Sicily and North Africa. This sub-oceanic ridge was a land bridge between Sicily and North Africa that submerged undersea as sea levels rose after the last Ice Age. The landscape of these islands consists of indented coastline, low lying hills with terraced fields. There are no permanent rivers or lakes on the islands and very little natural vegetation (Website 2).


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Figure 1: Google map showing location of Malta almost in the center of the Mediterranean Sea.

Figure 2: The geographical map of the Republic of Malta showing three main islands, they are Malta, Gozo and Comino (Website 1).


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Figure 3: A view of Valletta, the capital city of Malta (Photo: the author, August, 2014).

Figure 4: One of the large numbers of beautiful churches of Malta (Photo: the author, August, 2014).


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Geologically the Maltese Islands are young, primarily composed of marine sedimentary rocks, and the oldest rock formation dates back to the Tertiary Period. However, the platform over which these islands are situated was formed during the Triassic, but there are no surface outcrops of this age. Only Oligocene and Miocene rocks outcrop on the islands. Outcrops of terrestrial Quaternary sediments too occur on the islands (Figure 5: The geological map of the Maltese Islands). The lithostratigraphy of the islands can be summarized as follows (Website 3 and 4):

Lower Coralline Limestone Formation (Oligocene) is the oldest, its outcrops form vertical cliff about140 m high in Gozo (Figure 6). This limestone formation is composed of coralline algae indicating deposition in a shallow marine environment. Globigerina Limestone Formation (Miocene) overlies the Lower Coralline Limestone Formation and its outcrops cover nearly 70% of the area of these islands (Figures 5, 7, 8, 9). The formation thickness varies considerably, ranging from up to 23m in Gozo to around 207m in Malta. These are yellow to pale-grey limestones comprising tests of planktic globigerinid foraminifera. Blue Clay Formation (Miocene) overlies the Globigerina Limestone Formation. These are marine clays deposited up to depths of 150 m. Greensand Formation (Miocene) consists of bioclastic limestones rich in mineral glauconite, was deposited in a warm shallow sea. The thickness of this formation is usually less than 1 m but attains a maximum thickness of 11m in localised depressions in Gozo. Upper Coralline Limestone Formation (Miocene) is the youngest Tertiary formation, is around 160m thick in the Bingemma area, Malta. This formation resembles the Lower Coralline Limestone Formation due to the common occurrence of coralline algae, indicating deposition in shallow marine waters.

These marine sedimentary rocks are sporadically overlain by Quaternary terrestrial, aeolian and alluvial deposits laid down following the emergence of the Maltese Islands above the sea level. Much of the central and south-eastern portion of the Maltese islands comprises outcrops of Globigerina Limestone while the northern and north-western regions are characterised by highlands on which upper coralline limestone is the dominant outcrop. Fossil remains of prehistoric animals have been found in the caves of Malta (Website 4).

Oil Exploration around the Maltese Islands The newspaper ‘Malta Today’ dated March 7, 2014 gave the following information about the hydrocarbon exploration history of Malta (Website 5). Malta’s location at the center of the Mediterranean Sea, surrounded by proven oil and gas fields in offshore Sicily, Libya and Tunisia, makes Malta's offshore regions attractive for petroleum exploration.


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Figure 5: The geological map of the Maltese Islands (Website 3).


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Figure 6: Cliff section of the Lower Coralline Limestone along the southern coast of Malta (Website 3).

Figure 7: The urban region surrounding Valletta is situated over the outcrops of Globigerina Limestone (Photo of the author taken by a fellow tourist, August, 2014).


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Figure 8: An aerial view of the cliff section of the Globigerina Limestone southwestern coast of Malta (Photo: the author, August, 2014).

Figure 9: A cliff section of the Globigerina Limestone northern coast of Malta Island (Photo: the author, August, 2014).


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Since 1971, seven wells have been drilled, two of which were suspended. Major players like Shell, ENI, Amoco and Texaco have drilled wells without commercial discovery yet. Experts consider that the sedimentary basins offshore Malta possess good, drillable structures analogous with existing producing fields in the Central Mediterranean. In these geological structures, there is high probability of petroleum in commercial quantities.

Cairn Energy and Mediterranean Oil and Gas will very soon commence on a seismic

survey to the north of Malta searching for new drillable prospects that possibly may have been overlooked in the past. Depending on the results of the seismic surveys, the companies may enter into a production sharing contract with the Government of Malta for drilling of an offshore well.

The drilling company Genel Energy is conducting oil exploration in Malta's Offshore

Area 4. Geologically, this area has good prospects for commercial oil discovery. The first result of oil drilling in Malta is expected by mid-July, 2014 since drilling will begin around the end of March, 2014. Figure 10 shows stratigraphy of offshore regions of Malta clearly indicating a much longer geological history of these islands than seen from the outcrops.

Early Human History

As suggested by archaeological evidences these islands were first settled in 5200 BC

by Stone Age hunters or farmers. Evidence of prehistoric farming settlements of Early Neolithic period were found in open areas as well as in the caves like Għar Dalam. These early people in Malta grew cereals and raised domestic livestock (Website 6).

Website 1 provides the following very interesting information about the early human

history in the Maltese Islands. Malta being such a small place yet having such long human history is truly remarkable.

“During 3500 BC, these people built some of the oldest existing, free-standing

structures in the world in the form of the megalithic Ġgantija temples (Figure 11)on Gozo; other early temples include those at Ħaġar Qim and Mnajdra (Figure 12). The temples have distinctive architecture, typically a complex trefoil design, and were used from 4000 to 2500 BC. Animal bones and a knife found behind a removable altar stone suggest that temple rituals included animal sacrifice. Tentative information suggests that the sacrifices were made to the goddess of fertility, whose statue is now in the National Museum of Archaeology in Valletta. The culture apparently disappeared from the Maltese Islands around 2500 BC. Archaeologists speculate that the temple builders fell victim to famine or disease.”

“Another interesting archaeological feature of the Maltese islands often attributed to

these ancient builders, are equidistant uniform grooves dubbed "cart tracks" or "cart ruts" which can be found in several locations throughout the islands with the most prominent being those found in an area of Malta named "Clapham Junction". These may have been caused by wooden-wheeled carts eroding soft limestone.”

“After 2500 BC, the Maltese Islands were depopulated for several decades until the

arrival of a new influx of Bronze Age immigrants, a culture that cremated its dead and introduced smaller megalithic structures called dolmens to Malta. In most cases there are small chambers here, with the cover made of a large slab placed on upright stones. They are


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claimed to belong to a population certainly different from that which built the previous megalithic temples. It is presumed the population arrived from Sicily because of the similarity of Maltese dolmens to some small constructions found in the largest island of the Mediterranean Sea.”

Figure 10: Stratigraphy of offshore Tunisia and Malta (Website 2).


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Figure 11: Ġgantija megalithic temple complex (Website 1). Għar Dalamor the "Cave of Darkness" This cave is around 144 m deep but only the first fifty m is open to visitors (Figure 13). It contains fossil bones of animals that became extinct in Malta by the end of the last Ice age. Dwarf elephant (Figure 14), hippopotamus, deer and bear were found in this cave but these animals became extinct during different times; the hippopotamuses became extinct about 180,000 years ago, while the deer became extinct much later, about 18,000 years ago (Website 6).

It is also here that the earliest evidence of human settlement in Malta, some 7,400 years ago, was discovered. During archaeological investigation of this cave in 1987, Palaeolithic cave art depicting human hands, anthropozoomorphic, and several animal designs underneath the stalagmites were discovered. Some depict elephants which have been extinct in the Maltese region since the Pleistocene. There is a museum which exhibits a remarkable collection of fossil animal bones and human artifacts (Website 6).

Stratigraphyof Ghar Dalam: The following stratigraphic sequence of six layers, their lithology and fossils contents is given in Website 6.

1. Domestic animal layer (c. 74 cm). This layer has mainly cultivated animals in it, such as cows, horses and sheep/goats. Remains of human settlements like pottery, flints, tools and ornaments or amulets were also found in it.


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2. Calcareous sheet (c. 0.6 cm). 3. Deer Layer (c. 175 cm). The dwarf deer found in this layer are derived from the

European Red Deer, Cervus elaphus. Even small numbers of carnivores are known from this layer. Namely brown bear, red fox and wolf. Also big swans, giant turtles and voles are found.

4. Pebble layer (c. 35 cm). This layer consists completely of small boulders and pebbles. They are indicators of a river that streamed through the cave. Since the stones are quite large, it was a fast-flowing river.

5. Hippopotamus layer (c. 120 cm). This layer consists of mainly Hippopotamus melitensis. Other species found are dwarf elephant and dormouse, Leithia cartei.

6. Bone-Free clay layer (c. 125 cm). No bones found in this layer, only some impressions of plant material.

Figure 12: The temple complex of Mnajdra (Website 1).


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Figure 13: Għar Dalam or the "Cave of Darkness” located on the Malta Island (Website 6).

Figure 14: Fossil of the juvenile elephant at the museum in the Għar Dalam, Malta (Website 6).


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Suggested Readings: Abela, J. S. 2014. Malta: a brief history. BDL Publishing, Malta. 255 p. Website 1: http://en.wikipedia.org/wiki/Malta Website 2: http://www.gerom.org/page.asp?ID=7 Website 3: http://www.emwis-mt.org/documentation/Context/Physical%20factors_files/Geology.htm Website 4: http://users.aber.ac.uk/jpg/malta/geology.html Website 5: http://www.maltatoday.com.mt/news/national/36266/genel-expects-first-results-on-oil-

drilling-by-july-hayward-20140307#.VDchJnQtDtQ Website 6: http://en.wikipedia.org/wiki/G%C4%A7ar_Dalam Dr. Arun Kumar is an Adjunct Professor, Department of Earth Science, Carleton University 1125 Colonel By drive, Ottawa, ON K1S 5B6, Canada. Email: [email protected]

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Geology and Early Human History of the islands of Malta ...earthscienceindia.info/popular archival/download.php?file=pdf-59.pdf · hunters or farmers. Evidence of prehistoric farming