Generation and Assessment of Intrusion Related Pb-Zn and Au Targets in Muğla Province

ÖZET

Muğla ili çevresinde intrüzyon bağlantılı mineralizasyonları tespit etmek her ne kadar zor görünse de, özellike Bodrum yarımadası bu tip formasyonlar için oldukça uygundur. Çalışma kapsamında Muğla sınırları içerisinde bir çok saha dikkatle incelenmiş olup, Bodrum Yarımadası üzerinde oldukça ilginç mineralizasyonlar tespit edilmiştir. Epitermal ve Skarn tipi mineralizasyonlara ev sahipliği yapan, ve muhtemel bir porfiri bakır tipi maden yatağını barındırdığı düşünülen Bodrum Yarımadası’na yoğunlaşan bu çalışma, oldukça dikkat çekici bulguları sizlere sunmaktadır.

1.INTRODUCTION
1.1. Purpose

We are supposed to be working as project geologist for a mining and exploration company. The Au and Pb-Zn oreS that has been operating currently by our company, and the company is seeking new targets to feed the processing plant. Therefore, the company is urgently looking for new intrusion-related occurrences that could be evolved to an ore deposit. The company decided that it could be profitable if the new occurrence could be discovered in Muğla (Turkey), and they are planning to set up a new processing plant somewhere between Milas and Bodrum. As we are presumed to be in charge of discovery of the new. We ate asked to use descriptive and descriptive empirical and genetic conceptual models for intrusion-related deposit type that could host Au, Pb and Zn mineralization. This project should be conducted in two subsequent stages; first stage, the target generation, target selection, field works including primary reconnaissance; and second stage, target assessment and preliminary exploration. The aim of the study is to determine the intrusion related Pb-Zn and Au mineralization targetwithin the borders of Muğla province and to carry out a preliminary exploration program to determine if target fulfilling the above mentioned mineralization could be discovered. In the scope of the study, the target that should be discovered must be close to the processing plant, and should be set-up somewhere between Milas and Bodrum districts of Muğla province.

1.2. Location

Mineral exploration work has been carried out in Turkey, Mugla province (Figure 1), and in particular the areas with known magmatic rocks are xposed were examined.

Figure 1. Illustration of examined area in Turkey.

1.3. Exploration Strategy

1.3.1. Methodology

This work is planned in five successive stages; (1) desk studies to pin-point the spatial distribution of the intrusions and/or subvolcanic rocks exposed in the area between Milas and Bodrum; (2) testing the lithological and structural controls for intrusion-related deposits associated with the magmatic rocks identified at stage 1; (3) checking the availability of the previous mining and exploration works in the area between milas and Bodrum, (4) identifying the targets, and (5) assessing the targets. The desk studies and literature survey have been applied to determine (1) outlining and locating the areas in which the magmatic rocks including intrusions and subvolcanic rocks are exposed. The areas characterized by intrusive and subvolcanic rocks between Milas and Bodrum have been selected as regional ratgets. The scond stage involves defining defining the lithological and structural controls of intrusion-related mineralization class. In order to test the validty of the mineralization in the regional targets, the lithological contacts between intrusive and carbonate rocks; and intrusive and subvolcanic rocks emplaced or aligned parallel to major structural elements have been selected. The third stage involves defining the key features for the intrusion-related Pb-Zn and Au mineralization. Any area with intrusive-carbonate rock pair is identified has been selected as target for skarn type mineralization. Besides, any area with arc-related subvolcanic rock association is observed has been marked as target for porphyry Cu mineralization. As a result of desk studies, favaroble areas may indicate mineralization are spotted in the region. Subsequent to testing of geological settings for the presence of key features, the work has directed to the target assessement part that indicates field works.

1.3.2. Project planning

The exploration program was carried out within four-phased plan, and these phases are listed as follows;

1. Regional targeting
2. Target assessment
3. Field works
4. Prospect generation

Regional targeting covers a decision making to select areas presumed to be favourable for Pb-Zn-Au mineralization by the assistance of exploration criterias. For this purpose, listed deposit types in which Pb-Zn and Au could be economically viable is determined. Then, the key features for each deposit type was highlighted. The regional targets, the favourable grounds, then were decided as areas in which at least three or four of the key features are observed. Then, the favourable areas were tested against the geological database available in the literature. If the geological data favors smaller areas of interest in the regional targets, then these areas were referred to as favaroble targets (target assessment) for further exploration techniques such as field works. The target assessment is made taking into consideration the possibility that will have a mineralization being sought. In the fourth phase, the signs of the mineralization (structural control, color difference, geological units) are evaluated for preliminary observation, and technical visits are performed on the site. When the potential parameters are supported by field observations, the traces of mineralization were followed. If all findings are convincing that the region is worthy to work, we move to the level we call prospect generation.

1.3.3. Budget

Since mining exploration does not include drilling, laboratory analysis and thin section preparation, only fuel, food, and accommodation and maintenance costs considered as the budget. Last but not least, the fieldworks have been done by single geologist, and Table 1 summarizes these costs.

Table 1. Average costs of field work performed as a single person.

2. AN OVERVIEW OF INTRUSION-RELATED MAGMATIC-HYDROTHERMAL DEPOSITS

The mineral deposits planned to be studied within the scope of this project are intrusive-related magmatic-hydrothermal deposits. Throughout this section, prospective intrusion related deposits in Muğla province going to be described, respectively.

2.1. Porphyr copper deposits

The porphyry copper systems constitute the majority of the mineralizations observed near the converging plate movements. In addition to the presence of porphyr copper deposit inside the plutonic core; skarn, carbonate-replacement, and sediment-hosted, and high or low-sulfidaton epithermal deposits can also be found around the system. These types of deposits take their names from the porphyritic plutons located at paleo-depths of 5-15 km. The large-toned but low-grade porphyry copper deposits host Cu + – Au, Mo mineralizations around the intrusion, but Cu-Au or Zn-Pb skarns in the carbonate wall rocks, and Au-Ag rich epithermal systems on the near-surface depths may performed during the porphyr copper deposit generation (Sillitoe, 2010). The porphyry copper deposits are mostly formed by convergent plate tectonics and compressional regimes in subduction zones where magmatic arcs located (Sillitoe, 1972; Richards, 2003). Finally, porphyry copper systems have a wide range of alterations (Figure 2), and these alterations may be listed from deep to shallow as follows, potassic, chlorite-sericite, sericitic, and advanced argillic (Meyer and Hemley, 1967; Sillitoe, 2010). The basic characteristics of the porphyry Cu deposits that could be used as key features to be used an exploration criteria are presented in Table 2.

Figure 2. Generalized alteration-mineralization zoning pattern for telescoped porphyry Cu deposits (Sillitoe, 2010).
Table 2. Tectonic settings and alteration assemblages of porphyr copper.

2.2. Epithermal Deposits

Epithermal ore deposits form at shallow depth nearly 1 to 2 km, and the fluid intrusions to the epithermal systems calculated as lower than 150-300 C based on ore mineralogy, related textures and alterations (Lindgren, 1933). The systems divided by two , depending to their characteristics (Table 3), and related with calc-alkalic or alkalic volcanic rocks (White and Hedenquist, 1995). As shown on the Figure 3, low sulfidation type deposits contain fluids that has spreaded through a paleo-geothermal system subsequently (Henley and Ellis, 1983; White and Hedenquist 1995).

Figure 3. Relation of fluids in two styles of epithermal deposits. (Hedenquistat et. al., 1994).

But in contrast, high sulfidation systems show high sulfidation state mineralization content resulted of acidic and oxidized fluid intrusions formed in magmatic environment. In addition, low and high sulfidation type epithermal environments also called as adularia-sericite and acid-sulphate types.

Table 3. Main characteristics of epitermal deposits

2.3. Skarn Deposits

Skarn term refers to coarse-grained calc-silicate rocks, and skarn deposit refer to the mineralization that develops within this rock (Table 4). Skarn type ore deposits are located at relatively shallow paleo-depths (almost 5 km) in the temperature range of 400-650 Celcius degrees. Furthermore, these types of systems, which contain mineral and mineral groups such as garnet, pyroxene, pyroxenoid, amphibole, and epidote. In addition, these types of systems often develop due to convergent plate tectonics, and are similar to the formation environments of the porphyry copper systems (Figure 4). Last but not least, skarn type deposits may also cause the formation of epithermal systems in some cases.

Figure 4. . Idealized cross section of a typical, simple porphyry copper system showing the position of skarn-type copper deposit (Sillitoe, 1973).
Table 4. Key features of skarn deposits.

3. FAVORABLE AREA SELECTION

3.1. Key Features

All intrusion-related ore deposits form almost in the same tectonic settings, and these tectonic environments mostly occurring in subduction zones with the magmatic arc occurrences. When we look at the Muğla region, we can see that parameter, which is a basic requirement, has developed only in the Bodrum Peninsula. As shown in Table 2, the main features of possible intrusion-related mineral deposits in the province of Mugla have been fulfilled in the Bodrum Peninsula. Last but not least, also Datça Peninsula may host some magmatic intrusions or volcanic rocks, nevertheless most of the peninsula is covered by pyroclastic rocks such as tuff. Besides, they are out of the project area as being far away from the Milas-Bodrum region.

Table 5. Classification and characteristics regional targets in Muğla province.

3.2. Favorable Areas for Porphyr Cu Mineralization

Bodrum peninsula is a forable ground for porphyr copper deposits. The main reason for that is the presence of volcanic arcs formed by convergent plate tectonics. The region is rich with magmatic intrusions, and it is possible to have a porphyritic pluton at deeper levels of crust.

3.3. Favorable Areas for Skarns and Skarn deposits

Just as in the above-mentioned porphyry copper-type ore deposits, skarns and skarn deposits develop around volcanic arcs formed by convergent plate tectonics. The only region that provides magmatic intrusions cutting through the carbonate rocks are identified at the Bodrum peninsula.

3.4. Favorable Areas for Epithermal Au Deposits

Conditions required to form an epithermal system are available in the Bodrum Peninsula where the color anomalies due to argillic alterations and structural features controlling these anomalies are identified.

4. TARGET ASSESSMENT AND SELECTION OF EXPLORATION PROSPECTS

All of the targeted areas are located on the Bodrum Peninsula, and this is mainly due to the volcanically active geological history of the region. The favorable rock units hosting or associated the mineralizations are named as Pirentepe, Bozdağ, Boztepe, and Dağbelen formations from south to north respectively. Detailed information will be provided after the preliminary information of the evaluated areas is given. The Pirentepe area corresponds to the summit in to the south of the Bozdağ and Boztepe formations. At first place, plenty of magmatic rocks in the field have been observed. Another thing worth noting is the clay alteration with the yellow-light brown color, that can be observed on the highway slopes around the hill, and the disseminated pyrite content of this alteration (Figure 5). Although it is difficult determine the type of the main rock in the region, we can say that it is a porphyritic volcanic rock, even andesite rock, from the texture and the dominant rocks in the vicinity. Unlike the other rock units, it is quite interesting that this region, which shows advanced argillic alteration, has not been seriously studied in the past.

Figure 5. Argillic alteration and disseminated pyrite.

Boztepe formation that hosts a skarn occurrence located at the east of Kadıkalesi and South of Gümüşlük, is composed of dolomitic limestones, that were recrystallized along the monzonite intrusives at and around Boztepe. Additionaly, trachyte dykes cut across the marble, and the faulted contacts between dolomitic limestones and andesite-trachyte rocks are the locations for silicification and pyrite mineralization, within 30-150 cm thick quartz veins parallel to the faulted contact. The ore deposits of Pb, Cu, Zn formed around Boztepe have been operated in ancient times (Ercan et al., 1982). The slugs and dump sites are now exposed on the eastern flanks of the Boztepe (Figure 6).

Figure 6. The slugs and dump sites.

Bozdağ formation is composed of the hornfels formed by the contact metamorphism in the contact zones of the monzonite pluton in the Bozdağ Hill and its surroundings, while the flyish sediments of the Bodrum formation lose their primary rock state. Additionaly, hornfels can be defined as greenish and brown colored, hard and silicifed rocks that could be named as calc-silicate hornfels instead of skarn term. As a result of examination of thin sections according to Pişkin (1980), the samples contain mostly quartz and feldspar (albite), less chlorite, epidote, actinolite, which show blasto cataplastic and poikitic textures; quartz and albite, blasted cataclysmically and arranged in a very specific direction. Trakitic and syenitic dikes related to the second volcanic phase, have brought hydrothermal ore bearing fluids in discontuinities. In particular, the trakitic dykes contacting the dolomitic marbles near Monzonite around Bozdağ Hill, have developed in directions intersecting each other at diagonal and vertical directions. The contact of the trachkite with the marbles is limited by faults and these fault zones are filled with copper-lead-zinc mineral assemblages precipitated by hydrothermal solutions (Ercan et al., 1982).
The Dağbelen formation corresponds to a Skarn type mineralization cut by the monzonodiorite in the South and the rhyolites in the North and East, that is located in the Northeast of the Bozdağ and Boztepe formations near the Dağbelen village. In addition, this skarn formation has been cut at the same time as the Boztepe and Bozdağ mineralizations, although it has been cut with latite-andesite intrusions (Pişkin, 1980).

4.1. Pirentepe Mineralization

The Pirentepe formation has strong findings indicating an epithermal system. The most important of these is undoubtedly the “advanced argillic” alteration, and is observed on the porphyrytic intrusions in the region. In addition, the non-silicified clay alteration at lower altitudes is also interesting. The main rock in the region can be named as andesite, with a volcanic rock in the porphyritic texture (Figure 7). However, it is very difficult to determine the name of the rock without detailed examination, because the mineralogical characteristics of the rocks are not distinguishable due to the high degree of alteration.

Figure 7. The relatively fresh volcanic rock with porphyritic texture (A) and the vuggy texture (B)

Additionaly, most of the rocks in the region are silicified and carry the “residual quartz” characteristics. Over and above, the “advanced argillic alteration” texture, which indicates “advanced leaching” and has effected all rock masses, is also detected as the development of vuggy texture (Figure 8). However, when secondary quartz minerals can not be observed when examined as hand specimen, it is thought that the ore zone may have undergone erosion.

Figure 8. The advanced argillic alteration in the form of vuggy texture that has affected the entire volume of the sample.

On the other hand, although secondary quartz crystals can not be observed with the naked eye, Çetin (2017) detected secondary quartz-alunite within the cavities during petrographic analyzes (Figure 9). These occurrences refer directly to the ore-containing vuggy quartz zone, which means that the possibility of the system being able to precipitate gold.. When evaluated spatially, the following conclusion can be drawn, while the “vuggy quartz” and “advanced leaching” develop within intrusions at the shallower depths from low pH solutions, there is an “intermediate argillic alteration ” at the bottom where “residual quartz” structure is not observed. Briefly, this staggered formation can be likened to a typical high sulphidated epithermal system (Figure 10).

Figure 9. Photomicrographs (XPL views) of samples from Pirentepe displaying quartz and alunite (alun) alteration minerals precipitation named vuggy quartz.

In addition to all these, the silicified breccias found at the highest points of the Pirentepe region are quite interesting. As shown on the Figure 11, the almost fully silicified formation is likely to be a vein containing gold., and If sampled and analyzed in the lab, there is a possibility of containing gold even in small quantities.

Figure 10. Typical alteration zoning in a high sulfidation epithermal system (Hedenquist et. al., 2000).

In addition, because of the idea that the system has a fault, there is a high probability that the breccias are fault-broken. Because Pirentepe Epithermal does not show stratabound depositional characteristics, it should be thought that it can be fault controlled. Besides, very thick, crustiform-type silica veins (Figure 12) have been identified near these fault breccias and the thickness of the banding can be a sign of a fault plane. After that, there are both banded veins and silicified breccias, as well as vuggy quartz at the same location.

Figure 12. Crustiform bandings.

Finally, the surface oxidation observed on the surfaces of intrusions is quite striking. In these oxides, goethite and malachite occurrences are observed (Figure 13).

Figure 13. Botryoidal textured iron oxides.

 

4.2. Kadıkalesi Mineralization

In this section, the mineralization in the Kadıkalesi will be described. Mineralization within the site was developed around Bozdağ Hill and Boztepe, located in the Northeast and East of Kadıkalesi neighborhood. The dominant rock types in the region are dolomitic marbles and monzonite pluton, together with andesitic and trachytic intrusions. In addition, mineralization is also included in the flysch which is located on the South-West of Boztepe and turned into contact metamorphism hornfels. Pişkin (1980) found that there are Mn-mineralizations especially in the southern and eastern slopes, together with the Pb-Zn-Cu mineralizations in the region. In addition, there are several mining galleries operated in the past on the northern slopes of the site. There are two types of mineralization that are vein-type and disseminated in the region. The disseminated mineralization is mostly focused along the contact zones of dolomitic marbles and pluton, and vein type mineralization is observed around andesitic and trachytic intrusions. Kadıkalesi mineralization is host to both calc-silicate hornfels and magnesium skarn. In addition, there is an increase in ankeritized marbles and hornfels around the fault plane (Figure 14 and 15) located between Boztepe and Bozdağ hills. Additionaly, dark gray ankerite formations on the fault plane are elongated along the direction of the fault movement, indicating that the fault is still active after the activity of the metasomatic fluids.

Figure 14. The sample taken from the silicified fault mirror located between Bozdağ and Boztepe.
Figure 15. Ankeritized hornfels..

Conversely, there is no economic mineralization in the calc-silicate Hormfels in the region, but very fine grained garnet and pyroxene minerals formed between the bedding planes of protolith rock can be observed difficulty. The main reason for the lack of economic mineralization in the hornfels is the grain size, and the permeability and porosity of the fine grained rocks will be low, so metasomatic fluids will not be able to influence them. However, the situation is different in recrystallized limestone, and vein-type and disseminated galena mineralizations (Figure 16) can be observed along the contact between the intrusions and the marbles.

Figure 16. Galena (A) and Pyrite (B) mineralizations formed in marble.

In addition, pyrite and chalcopyrite is common with galena. Furthermore, azurite and malachite mineralizations have been observed in the drosses of the ancient mining activity in the region, and the system contains the whole of Galena, Pyrite, Chalcopyrite, Azurite, and Malachite ores (Figure 17). In addition to all of these, in this system of skarn type, a small amount of magnetism is detected in the majority of the sampled rocks, and it is estimated that the system contains magnetite minerals even in low quantities.

Figure 17. Azurite (A) and Malachite (B) contain copper element.

 

4.3. Dağbelen Mineralization

It corresponds to a magnesian skarn which is located at Dağbelen village. Although relatively intense galena mineralizations have been observed in the region, relatively low amounts of sphelarite have been observed. The system, predominantly containing galena and sphalerite, has been operated in the past. Numerous research pits and mining galleries have been identified around the study area. It is interesting that this region, which hosts remarkable mineralizations, has not been examined in details in the past years.
The first occurrence that is noteworthy in the vicinity of mineralization is the clay alteration, which is not showing advanced argillic alteration characteristics such as vuggy texture. This clay alteration is widely observed in the area between Kadıkalesi mineralization and Dağbelen mineralization. Figure 18 illustrates the porphyritic host rock influenced by selective pervasive alteration.

Figure 18. Sanidine crystals preserved in the porphyritic hostrock.

It would not be wrong to comment that skarn and epithermal system work together by going out of the surrounding clay alteration. In addition, the presence of volcanic breccias in the environment, which are associated with clayed and silicified volcanic breccias, may indicate a stratabound epithermal system (Figure 19). A detailed investigation should be conducted to determine this condition, as there are no studies on the investigation of these volcanic breccias in terms of mineral deposits. In addition, if the orientation of the clasts in the volcanic breccia is examined, it can be observed that some points carry hydrothermal breccia characteristics (puzzle effect). This situation strengthens the potential for ore inclusion.

Figure 19. Silicified volcanic breccias.

On the other hand, manganese dendrites are undoubtedly one of the first skarn-type mineralization finds (Figure 20). These occurrences are common in the environment, and manganese dentrites indicates a skarn at the underground.

Figure 20. Manganese dentrites on a clay altered rock.

The main reason for this is that the manganese element has the “immobile” property and can be carried to the surface in the fluid. The vein type mineralization shown in Figure 21 may indicate two different processes of the system. The minerals in the colors near claret red are Garnet and the dark colored ones are Pyroxene group minerals that shed light on the “Prograde” phase of the Skarn system. With them, green colored Epidote minerals are observed which are indicative of the stage of the “retrograde” phase on the prograde minerals. The vein formed in the sample cuts the paragenesis of the skarn mineralization, and contains the galena and pyrite alternation to the quartz, in the center. That occurrence may correspond to the epithermal overprint of the system.

Figure 21. Pyrite-rich vein that cuts through the skarn paragenesis.

In addition to these, we can observe all the phases of the Dağbelen skarn in a single sample (Figure 22). galena (1) and epidote (3) represent the “retrograde” phase of the system, and Garnet mineral (2) corresponds to “Prograde” (early) stage. In addition, although it is not visible in the image, sphelarite has also been observed in low quantities with Galena. This mineral is in yellowish color tones, and disseminated.

Figure 22. Ore bearing sample from Dağbelen region. Galena (1), Garnet (2), and Epidote (3)..

The mineralization of the Dağbelen is a reaction skarn, but it is also host to the formation of Calc-Silicate hornfels. However, the possibility of an economic mineralization in these Hornfels rocks is not possible due to their grain size. In summary, this skarn deposit has rich mineral paragenesis in the elements of Manganese, Lead, and Zinc, and in addition there is the possibility of being gold rich veins that are deposited in the epithermal period. Finally, a low magnetism has been detected in all sampled rocks, and the presence of magnetite mineral is predicted in the system.

4.4. Negative Grounds

Some fields are not covered by the study forwhy they do not involve the necessary parameters to develop an intrusion-related mineral prospect.

4.4.1. Muğla, Köyceğiz District

The basaltic rocks of Middle-Upper Triassic age, which gives rise to the southern skirts of Mount Sandras in the north of Köyceğiz Lake, are very interesting. The fact that the region is surrounded by normal faults, and that the Kartal Lake on Mount Çiçekbaba of Sandras Mountain has similar geometry like a volcanic (caldera) lake, and that the non-vegetated hill has colors similar to the clay alteration pattern when viewed from aerial photographs, thought us there may be a metasomatic activity. However, as a result of field work, no any hydrothermal alteration was observed in the area and the color difference was found to be due to sediments physically weathered, and there is no vegetation cover due to high altitude. On the other hand, the fact that Triassic basaltic rocks and the surrounding Upper Cretaceous carbonate rocks, have not been intruded by younger pluton, are indicative of negative signs for any intrusion related mineralization and skarn deposits. Finally, although diabase clasts were observed in the area, diabase intrusions stated by Graciansky (1968) were not observed.

4.4.2. Muğla, Marmaris, Turunç District

The Turunc formation with tectonically overlying Bozburun formation begins with Triassic sandstone-siltstone alternations and contains limestones up to the upper levels, with basaltic levels between these units and surrounded by ophiolites (Ercan et al., 1993). In addition, ophiolitic rocks in the region are intruded by diabase intrusions. The presence of normal fault control alongside the magmatic rocks suggests the potential to be an epithermal system, but no field evidence of hydrothermal alteration has been found in the region as a result of field observations. Moreover, no contact metamorphism was found in Jurassic carbonates surrounding Triassic volcanic rocks. Because the carbonates are younger, and there is no intrusive mineralization in the region.

4.4.3. Muğla, Datça Peninsula

As a result of the literature and geological map scanning, no intrusion-carbonate rock association was observed in Datça peninsula. Scanning from satellite photos also did not provide traces of the epithermal system. Since the region has a cover of pyroclastic units, it has come to the conclusion that it is not efficient to exploration for a prospective mineral deposit.

4.4.4. Discussions

The result achieved in the context of the studies carried out within the scope of the preliminary survey is that; within the Muğla provincial borders, it is the only place on the Bodrum Peninsula where intrusion-related mineralization should be explored. Although the volcanic and plutonic rocks were found in other areas, the above mentioned fields were eliminated because no alteration or mineralization was observed in the areas.

6. DISCUSSIONS

Bodrum Peninsula is a very active region in terms of volcanics, which may host and suitable for many types of mineral deposits. This study has shown that the skarn and the epithermal type mineralizations are predominantly galena mineral rich, and relatively poor for such as Zinc, Manganese, Iron, and Gold elements. At present, the Kadıkalesi mineralization is a mineral deposit operated in the past years, and the Dağbelen skarn is also a site that has been explored by different companies. Except for these two regions, only Pirentepe mineralization has not been studied effectively and it may be important to examine it in detail. Although the systems located on the peninsula has no any economic significance, the real issue that should not be forgotten at this point is the fact that there may be a porphyry copper type mineralization at deeper levels. Although Bodrum Peninsula is a region with important attractions in terms of tourist and history, any world-wide economic depression that may be experienced in the future may make these mineral deposits important. Because the peninsula is home to two Skarn type mineralizations and a few epithermal systems on a large scale, which indicates the conditions that surround a typical porphyry copper system. The Bodrum Peninsula is also well-suited for the formation of mineral deposits due to its tectonic features, especially for the formation of porphyry copper-type mineral deposits. There is a high possibility that a magma carapace with a broken active tectonic regime around the magmatic arc formed by the subduction of Anatolian microplate under the plate of eurasia. On the other side, the copper rich samples from the Kadıkalesi region show that the magmatic fluids released from of porphyr copper system may have reached the surface. The mineralization of Kadıkalesi and Dağbelen Skarn, which is somewhat massive and vein type, may be of economic importance in the future, but this is not the case for Kadıkalesi Hornfels. Furthermore, Pirentepe mineralization has almost all the properties of a high sulphidation epithermal system and has an “advanced argillic” zone. Over and above, microscopic examination revealed secondary quartz mineral formations in vuggs (Çetin, 2017). However, these formations are insufficient in terms of the economy, the system has not found the possibility of depositing more ore yet. Another issue that needs to be addressed definitely and needs to be examined in another study is the silicified volcanic breccias found near the Dağbelen mineralization. It is noteworthy that these structures may point to a stratiform epithermal system due to the hydrothermal breccia traces. If the silicified volcanic breccias are broken again and form hydrothermal breccias, there is a possibility that the system may precipitate ores over and over again several times.

7. CONCLUSIONS

Within the scope of this study, Kadıkalesi and Dağbelen Skarns (Magnesium skarns) along with Kadıkalesi Calc-Silicate Hornfels and Pirentepesi epithermal system were investigated in the Bodrum peninsula. Although Hornfels formations and Pirentepe epithermal system seem inefficient in terms of mineral deposits, Kadıkalesi and Dağbelen Skarns may be economically important in the future. However, considering today’s economy, we can say that there is no economic Pb-Zn mineralization related to intrusion within the Muğla province borders. The epithermal system with silicified and clayed volcanic breccias observed in Dağbelen region, and the porphyry copper type system, which is likely to be in the region, are interesting, but this phenomenon does not go beyond a fantasy with the information provided by this preliminary research. It is unlikely to undertake a mining activity in the near future as long as the touristic profit brought by the archeological and geographical qualities of the Bodrum peninsula, is high enough to be earned by a mineral deposit.

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