EFEMÇUKURU GOLD MINE – İZMİR
With the Efemçukuru Gold Mine Project, the gold mine and related facilities were opened in the field with the operation license number IR 51792, located near the village of Efemçukuru, on the border of İzmir province, Menderes district, and they were put into operation as of 2011. Efemçukuru Gold Mine Activity Area, which is currently in operation, is located in the Aegean Region, approximately 20 km from İzmir province and 14 km from Menderes district.
Within the scope of Efemçukuru Gold Mine, the total ore to be mined is expected to be approximately 8.5 million tons, and the annual average production is approximately 600 thousand tons, in the light of the latest reserve development studies. The average grade of ore is 7.31 gr/ton for gold (Au); For silver (Ag), it was determined as 10.6 gr/ton.
Mine Operation Method
The mine production method to be used in the Efemçukuru Gold Mine site and within the scope of the proposed Project is underground mining and excavation and the filling system will be used.
The production method will be realized by underground drilling, blast loading, transportation, and filling with a special design. The ore preparation phase includes crushing, starting with milling, followed by multi-stage flotation of gold and silver. The final flotation concentrate will be subjected to gravity processing to obtain free gold. After the gravitation process, the metal obtained will be melted and cast in the form of gold.
The flotation concentrate containing the remaining metal sulfates and fine gold will be transported to another facility for further enrichment for gold production. Flotation wastes will be sent to the filtering plant and will be subjected to the dewatering process. Approximately 50% of the dewatered wastes will be mixed with cement, which is used as a binder, to be used as an underground filling, and the remainder will be stored in the dry waste storage facility, which will be created in the area and whose capacity will be increased.
EFEMÇUKURU GOLD MINE PROJECT HISTORY
|1992 – 1993
||Discovery, Licensing and Initial Research Studies
|1993 – 1997
||Continuation of Research Studies/ Engineering and Environmental Studies
|1998 – 2005
||EIA Preparation Studies
||Obtaining the EIA Positive Certificate
|2006 – 2007
||Feasibility and Research Drilling Studies
||Basic Engineering and Feasibility Study / Expropriation
||Obtaining All Permits / Detailed Engineering / Start of Construction Activities
||Continuation of Construction Activities, Research Drills in the Northern Region
||Termination of Construction Activities. Transition to Business
||Obtaining the Capacity Increase EIA Positive Certificate
Importance and Necessity
Gold is one of the least common metallic element in the earth’s crust. Only two-ten-millionths of the earth’s crust is gold. Gold is the best conductor known in nature and does not react with water and oxygen. In addition, gold, which is one of the most active elements, does not rust and does not rot because it does not react with oxygen. Due to this feature, it is widely used in many industries. Gold-plated surfaces are used to provide constantly clean, rustproof and reliable signals. It is also used in the medical and dental fields because it is not toxic and biologically active. Due to its reactive and non-hazardous nature, gold does not cause any decay or harmful physical reactions in the human body. It is the hardest to break of all metals and can be inserted into very thin wire or sheet shapes without breaking. These features have made gold a very important part of connectors in computers and telecommunications equipment. It is the substance that best reflects heat or infrared energy. High purity gold can reflect 99% of infrared energy. This suggests that gold is an ideal material for reflecting heat and radiation. Below, the evaluations regarding the usage areas of gold are given in articles.
- Use as an investment and savings tool,
- Jewelry production,
- Electronics and telecommunications (computers/semiconductors, spacecraft, telephones, televisions),
- Lasers and optics (astronomy, satellites, copiers, security systems),
- Medicine and healthcare (dentistry, laser, research, thermometer),
- Industry and aviation (airbags, aircraft engines, aircraft windows, engine systems).
According to 2006 data, the world’s gold reserves are 41,500 tons as operable reserves and 90,000 tons as apparent and probable reserves. Turkey’s gold potential is 6,500 tons. At the end of the gold mine exploration studies carried out for the last 15 years, the location of 800 tons of this potential has been determined. In 2010, world gold production was 2689 tons.
While Turkey’s position in Europe in terms of gold production was not remarkable at the beginning of the 2000s, it made significant progress at the end of the 2000s and became a country that holds about half of the European gold production with its 2010 production.
In addition to the above-mentioned assessments, the project is expected to contribute to the issues identified under the following sub-headings.
While many situations directly related to the project provide socio-economic benefits in the region, it is possible to evaluate this change/development under basic sub-headings such as macroeconomic benefits, employment opportunities, education opportunities and awareness, and infrastructure development.
Details on these are given below.
- Gross domestic product (GDP) growth at the country and province level over the economic life of the project,
- Increase in government revenues throughout the economic life of the project, due to the expansion of the tax base,
- Strengthening the balance of trade and payments throughout the country throughout the economic life of the project,
- Contribution of goods and services purchases to be made throughout the country to the economy,
- • It is aimed to supply personnel and purchasing needs from the field of activity and its immediate surroundings as much as possible. This brought the project to be a source of employment for the region. This will continue to positively affect the income and quality of life of many households in the surrounding area. The direct and indirect additional job opportunities created by the project will also help the surrounding settlements to develop their economies. In addition to the direct job opportunities that the project will provide, the increase in the population in the region due to the indirect job opportunities due to the multiplier effect of the project will increase the demand for resources, goods, and services, thus creating new employment areas.
- It will be ensured that the people living in the vicinity of the activity area and in the region can benefit from direct and indirect job opportunities during the project. Another important benefit to be gained from the project will be raising awareness of the local people on health, occupational safety and environmental issues during the recruitment phase. Staff will be trained on safety and environmental issues.
Additional infrastructure investments (road, etc.) to be made within the scope of the project can be used after the end of the mining activity.
The young geological formation of the Izmir region can be explained by three different paleotectonic units affecting each other. These are listed as follows from east to west (Şengör and Yılmaz, 1980).
- The Menderes Massif Metamorphites, as the oldest unit, are located in the easternmost part of the region.
- The NE-SW trending İzmir-Ankara Ophiolite Zone, formed by the closure of the Neo Tethys ocean.
- The Karaburun Block, which is formed by platform type carbonates and is thought to be an extension of the Sakarya Continent.
In the Early Paleocene, the Neo Tethys Ocean was closed by the push of the Menderes Massif towards the Sakarya Continent, forming a regional metamorphism zone (Şengör- Yılmaz,1981; Akkök, 1985). Later, the extension and subsidence zone that started in Miocene in Western Anatolia caused the formation of mostly east-west oriented horst and graben type structures. The calc-alkaline magmatism, which started right after this structural formation in the region, later continued with trachytes and rhyolitic volcanic activities..
The İzmir-Ankara Suture Belt Region shows the closure point of a subduction zone separating the Sakarya and Anatolith-Taurus microlayers during the late Cretaceous and early Paleocene Ages. As the subduction zone closed, the Neo-Titian seafloor between the two microplates covered the upper layer of the Anatolith-Taurus plates. Serpentine lenses associated with thrust faults and recrystallized limestone olicytolites are subducted into complex mélange-like structures formed during suture formation.
Regional, extensive volcanism and intrusion activities have also been linked to subduction processes. In the western Turkey zone, the subsequent mid-Tertiary expansion resulted in block faulting and the emergence of the Seferihisar horst formed in the north-south direction. Efemçukuru Mine is located in the middle of the Seferihisar horst.
Geology of the Project Area
The Efemçukuru Gold Mine deposit is located at the western end of the İzmir-Ankara Zone. This western part of the Izmir-Ankara Zone is called the Bornova Melange by those who study the geology of the region. (Erdoğan,1990).
The project area consists of less deformation, relatively highly metamorphosed late Cretaceous-Paleocene-aged flysch. This volcanic sedimentary flysch unit was later cut by rhyolite dykes varying between 1-2 meters in thickness. Later, the Efemçukuru mineralization, which is called the Chestnut Beleni vein zone, was also emplaced in this unit. Around the project site, four main units (phyllite, hornfels, rhyolite, ore vein zone) have been distinguished.
Intermediate rock-mafic seafloor volcanic and interlayered mafic sediments (schists) in the northeast corner of the project area are inclined towards phyllites in the south and west directions. Phyllites and hornfelses are the primary host rocks for mineralization in the license area. Here, phyllites, which are not affected by hydrothermal degradation, are generally soft, fissile and have an advanced S1 foliation structure. The fractures in the phyllite are filled with fine metamorphic quartz-microcline veins. During regional tectonic events, the phyllites were strongly deformed. Foliation layer direction and slope direction change abruptly within short distances. The phyllites have been thermally metamorphosed into hornfels near the center of the deposit, covering more than 2 km × 2 km.
Decarbonization and silification of calcareous phyllite have formed a rock assemblage rich in epidote, tremolite and actinolite containing varying amounts of pyrite, pyrrhotite and base metals. Hornfelsization has embrittled the host rock, making them more susceptible to fracture and agglomeration than ductile pelitic phyllites.
Within the ore deposit, the highest grades of gold and the thickest vein intersections were commonly found in this hornfelsed rock unit.
The gold and base metal mineralizations in the Efemçukuru mine deposit contain two north-northwest oriented epithermal veins that cut hornfels, phyllites, and rhyolite dykes. In the region, the main vein is the Chestnut Belen vein. Another second parallel structure is known as the Kokarpınar Vein outcrop and is approximately 450 meters northeast of the Kestane Beleni vein. Kestanebeleni is located 500 m west of Kestanebeleni in the NW seam.
The Chestnut Beleni vein is characterized as a multi-stage accretionary (breccia) ore vein containing abundant host rock, vein fractures, and smaller, layered vein textures. The vein is located within the expanding segmental structure of a controlled fault, abundant agglomerations that have caused hydrofracturing, and an active fault system. In the plan view of the vein, it has a double-folded appearance. The geometry of this shape supports oblique, dextral-normal displacement over the fault-controlled system.
The Chestnut Beleni vein has a strike length of almost 1,100 m. Three ore zones are defined along the vein. These are: 1 Southern Ore Zone , 2 Central Ore Zones and 3 Northern Ore Zones. The Southern Ore Zone can be traced from the surface at an angle of 338° from the north, between 500 meters and inclination directions of 60°-68°. The southern half of the ore pier mostly consists of a single vein.