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  Economic Geology
The history of economic geology of Iran
Author : Mansour ghorbani
Publisher date : July 2002
Chapter title : Chapter 4 -States, belts, and mining and Metallogenic areas in Iran
Data title : 4-5 Takab Metallogeny Zone

Phases of mineralization in the Area Takab

1 - creating mineral phase Late Precambrian - Cambrian previous

 In this time period, Takab area, mineral deposits and signs of various nonmetal Mandarsab and zinc, iron, manganese, copper, barite, feldspar, talc and phosphate have been formed.
In addition to the deposits mentioned in the index was at this time, elements gold, arsenic, antimony, mercury, lead and zinc deposits that make up the Tertiary rocks of this time have originated.
In general, signs of mineral deposits and the Precambrian - Cambrian previously could be considering how to structure and form, the form to the following categories:

 20 - Precambrian mineral deposits and signs of late - the former Cambrian can be considering how to structure and form, the form to the following categories:

21 - sedimentary deposits and volcanic massive sulfide such as lead and zinc grapes, Science Kennedy, back mount, lead and zinc mining unit Mn Layout, Chahartaq iron, copper signs that are all bound and some stratigraphic of science such as lead and zinc and iron in the mountains behind the Kennedy and Chahartaq, San stratigraphy are also in the middle part Takab are rectangular (Figure 4-5).

22 - stratigraphic sedimentary deposits, stratigraphy are bound, such as barite deposits associated with iron in the East-months (for example Myrjan) and iron deposits Shahin Dej area (e.g. Mount comparable pieces), Shahin area Fort phosphate deposits. All deposits are mentioned mixed with Soltanieh.

23 - nonmetal deposits related to pLoutonic and metamorphic phenomena, such as feldspar, talc, silica, which may calving although some of them such as talc is after this time, but the mother rock in all of them related to the timing.

24 - There are elements of zinc, lead, iron, manganese, barium, copper, arsenic, silver, antimony, gold and...

Features of the deposits on the frequency that some of them like grapes, the amazing sets, and in some area of ​​science, such as deposits Kennedy, lead and copper prevail is usually low.
25 - geological evidence indicates that these mineral deposits, more stones activity and bypass the more acidic part (derived from their differentiation) and associated sedimentary rocks is dependent and in this regard can be said massive sulfide deposit grapes and other types of deposits is gone equivalently, the four-arch iron, lead and zinc Kennedy and science Dependence for sedimentary rocks with host rock, sedimentary and type Exclusively are.

26 - Based on geological evidence Takab rectangular middle part (region CI) and the characteristics of massive sulfide ore deposit types and the mentioned and compared with geological features of this region with some areas, other areas of Iran including Anarak, can be stated that the massive sulfide deposits Takab area in a medium similar to the Red Sea Rift formed, although some general features of massive sulfide deposits of the Red Sea is not the type.
27 - Sedimentary deposits, sedimentary - volcanic: As noted, these deposits, which mainly are deposits of iron and phosphate, are also being bound Stratigraphy, Stratigraphy of the San are. This direct dependence on deposits of volcanic activity are not only limited to, among some signs of iron Nagorno Dash series, mineralization associated with volcanic activity is demonstrable.
Some features of these deposits are as follows:

28 - All the deposits are in Soltanieh formation, but often with iron deposits and the underlying dolomite are sometimes associated with starting Soltanieh phosphate deposits, but often in the middle dolomite and dispersed throughout the upper and lower parts of the lower shale shale are high.

29 - Iron deposits often mineralogical composition of hematite, magnetite and siderite have spoiled them, and carbonate minerals are barite. Is noteworthy that when Nagorno Dash series rocks near the deposit is placed, mineralogical composition of the type of iron deposits but when this is magnetite deposits of Nagorno Dash series rocks are away, the mineralogical composition of most hematitic siderite and barite value is increased.

30 - Must be pointed out that sometimes rocks Nagorno Dash series anomaly in iron minerals and the type exists in the mountains maximum thickness of the Nagorno-Dash rocks can be seen as a sign of the type of iron mineral there.

31 – Ore Deposits of this kind outside of the region followed Takab is also available. so that deposits of iron mixed with dolomite Soltanieh (most of the lower dolomite) in area 9 in region Soltanieh Oshnovieh has followed up. All these deposits in the amount of storage, mineralogical, elemental Paragenesis, are very similar to each other.

Phosphate mineralization

Shahin stronghold in northeast region (especially in rural area and Haji Aman), Chile layers Soltanieh Formation (lower and upper shale), phosphate is often stained but the main focus of phosphate in the middle dolomite formation is Soltanieh. Shahin area Fort phosphate, phosphate of Alborz Zanjan region shows good agreement.

Mineralization phase Late Paleozoic - Triassic previous
Mineralization related to this phase, the quad Takab brief is as follows:

- Refractory deposits in the Fort area Shahin other refractory deposits in southern Iran and the Alborz Abadeh comparable.

- Iron ore deposit in connection with volcanic Permian, the deposits in the marine environment and when the limestone was deposited Ruteh, have been formed. Their major iron ore deposit is of volcanic origin other, iron ore area Fort Shahin is sedimentary origin.

 First deposit in Sanandaj - Sirjan is located and region of iron deposits falcon (which are concurrent with the falcon series) are comparable. Iron deposit located in the fort area and Shahin comparable iron deposit in the Alborz is Masouleh.

1 - Mineralization Mesozoic (Jurassic) Phase

Mesozoic mineralization in the quadrangle index Takab has happened and can only stronghold in the region and East Shahin-months, the signs of the formation of coal Shemshak noted. However, some layers of thickness of coal, economically significant, such as mineral Myrjan signs, Nasirabad East-months.

2 - Tertiary mineralization phases

Efficient and the most diverse phases of mineralization in the region in Tertiary Takab has occurred. The effects of mineralization, the only square in the middle part Takab (CI) is to be followed and there are not another intrusive rocks.

Tertiary phases of mineralization mainly occurred in the Neogene and so, here instead Tertiary phases of mineralization phases Neogene or younger we learn.

Neogene phases of mineralization, close relationship with the regional magmatic phases and Takab this reason, here the young magmatic phases of the compact region point.

3 - Lower Eocene volcanic phase Shahin Dej and East-months is seen that is not associated with mineralization.

4 - Eocene to Oligocene pLoutonic phase (zone diapirism C_I). Although in this phase, information is available on the right age and at the same time that Lee knew the transformation.
5 - Late Oligocene volcanic phase - which includes former Miocene rhyolite rocks – ignimbrite  and related tuff, andesite, and little is masses. In this phase and finally severe former Miocene has subsided.

Mineralization creating a variety of minerals including iron town and some signs of inorganic mercury with antimony and acidic rocks of this phase, is associated.

6 - The final phase of magmatic former Miocene - early middle Miocene. With the ebb and acidic volcanic pyroclastic acidic, volcanic andesitic - basaltic begins the mineralization is not significant.
7 - Late Miocene magmatic phase - Pliocene. In a Late Miocene volcanic phase of severe withdrawal and cutting andesitic bombs begins with the explosive eruption subsided, leaving the andesitic lava, basalt, and finally ends. In addition to andesitic volcanic activity - basalt, volcanic and pLoutonic activity of this phase of the Small Acidic that opinion writer, the main role in the mineralization has a young (Figure 4-4). Now that magmatic phases of the compact are introduced, creating mineral phases are described.

Oligocene Ore Deposit

Acid pLoutonic phase - Oligocene limited mineralization that can carry inorganic mercury Nagorno signs crow attributed to it.

Lower Miocene mineralization phase

The point being when sea sediments being deposited in basins Takab Qom formation was accompanied, calcareous sediments mixed with volcanic acid is mixed. Volcanic activity that began in the Upper Oligocene, the Miocene continues, so that the lower part of the Qom Formation is more composition.

In this basin, the Qom Formation calcareous rocks with acid tuff, rhyolite and and sometimes are mixed in the andesite. The general trend is such that the acid tuffs in are placed under the lime and andesite with lime, will find state between finger and sits on is lime. D. R. these conditions, extensive mineralization in the area Takab following occurred:
- Mineralization of iron: iron ore settlements, the largest known iron ore deposit in north-west of the country, clear examples of iron mineralization in the Lower Miocene is. Deposits according to geological field evidence, mineralogical and geochemical, volcanic origin and part of it can is done.

- Mineralization antimony, mercury, lead and zinc: effects of antimony mineralization are in the Lower Miocene zone valley is seen. The mineralization probably depends acid is associated with earlier Miocene Qom limestone deposition has been done, because in the area and range of mineralization, the host rock and ore zone are folded together and having to hack this phenomenon can also affiliated to the is phase. Likely to be part of garden mineralization, particularly nickel and cobalt has occurred at this time.

Mineralization phase of the middle Miocene (evaporites)

After the intensity of volcanic activity subsided in the end zone Takab Lower Miocene, marine conditions had the Qom basin, gradually found continental conditions in the area to the south Dandy-months due to Grabon structure, or change in marine facies conditions (conditions evaporation) in the middle Miocene is also maintained. Meanwhile, due to the composition of volcanic materials (Lower Miocene), large deposits of salt is composed primarily of many springs in the area some months show that the lower and middle parts of the red formations are a high source, rich in elements of K, Na, and Mg are.

Mineralization phase of Late Miocene – Pliocene

As previously noted, in this time period, most intense phase of volcanic masses and influence the type of small acidic granite, granite Porphyry in the middle region that occurred Takab evidence yet that hot springs can be seen. With this phase, the most diverse and most valuable phase of construction occurred and peak mineralization at the end of the Miocene and early Pliocene has been. Mineralization of some of this time belongs to, is as follows:
Gold and arsenic mineralization: gold deposits, arsenic Zarshuran, Aq Valley, Arabshahi formed at this time.

Mineralization of copper, lead and zinc: lead-zinc deposits such as IP Seif pachay Castle, part of the copper mineralization.

Iron mineralization: along with the andesitic rocks and Upper Miocene basalt - Pliocene, some iron ore and mineral volcanic birth sign is made of a. "number, you can deposit mount magnetite in volcanic rocks Baba Mountain and symptoms of mineral and Layout in the Layout area of ​​volcanic rocks named.

Manganese mineralization: soLoution thermal hot springs and volcanic related Late Miocene - Pliocene, Baba mountain range formed the have manganese ore.

Boron and magnesium sulfate mineralization: Sea of ​​remaining small lakes dried up former middle Miocene, the Late Miocene and thermal springs cause concentration and mineralization have been blond.

Analytical parity Tertiary deposits

To clarify the calving area Takab Tertiary deposits, pointing to a few important points are:
1 - Tertiary mineralization, and mew in Miocene - Pliocene that the mineralization as we learn young.
2 - Young mineralization, only the middle portion of rectangular Takab happened.
3 - young volcanic and pLoutonic similar mineralization, only the middle rectangle Takab peak occurred in the Miocene and earlier and was MioPoliocene. PLoutonic Late Miocene and Pliocene young occurred.

4 - Takab rectangular middle part where the young mineralization occurred, with Ultramafic basement - that is mafic in some parts, with carbonate rocks and Precambrian plate above - are accompanied by lower Cambrian. These rocks, exposed in the vast middle are Takab quad. See only the local rocks covers them, and volcanic rocks Hoya volcanic - sedimentary oligomiocene, including Qom and formations is high.

5 - Precambrian basement - middle Cambrian Takab rectangle, elements of gold, arsenic, mercury, lead and zinc in comparison with similar rocks, anomaly is that this form of origin Ultramafic rocks - mafic, the first lake of gold, and second in terms of arsenic and mercury anomaly and further show the origin of carbonate rocks, in terms of lead and zinc and the origin of volcanic rocks - Tuff acid plates than are antimony and mercury anomaly.
6 - Takab basement area to the younger deposits are:

A) The foundation stone Gold mining Arabshahi Zrshvran and symptoms of type peridotite and the carbonate sequence on their plates and rocks located.

B) Aq Valley gold deposit, up Ultramafic mafic basement and plates that are mixed with signs and inorganic antimony and mercury and horns - horns and Nagorno-crow, followed with an acid volcanic rock, granite plate has changed.

Multi-metal deposit, with basement Ultramafic - mafic Baychh garden by the fault of the Miocene volcanic cut and Brewer have taken him instead of it.


C) lead-zinc deposit, containing thirty Ay castle basement and mafic carbonate plates has changed.
7 - based on isotopic measurements of sulfur (S34,S32), significant similarities between lead and zinc deposits of late Precambrian - Cambrian previously (Kennedy and science of grape) and younger deposits such as Fort Ay C is seen.

8 - based on mineralogical studies paragenesis fluid and control mineralization in deposits by faults Castle C Ay, Aq Dareh, Arabshahi and garden, these deposits belong to different temperature hydrothermal soLoutions is evident. So that if based on these studies temperature hydrothermal soLoutions to consider the mentioned deposits are as follows:


Temperature increase in thermal soLoutions

Aq Dare – Zarshuran – Bayche Si

Studies are based on fluid temperature between 220 Zarshuran soLoutions to 180 ° C is obtained (Morris, 1993). Based on the temperature, thermal soLoutions Aq Valley is less than 180 ° C, Castle C IP soLoutions above 220 ° C hydrothermal ore soLoutions, more than 300 ° C and more than 400 in the first phase ° C respectively.

9 - folding and polyphase Alpine tectonic movements and the young masses magmatic intrusion into shallow parts of the crust, creating a series of fractures and the fault and therefore, suitable for duct flow of hydrothermal soLoutions is provided.

10 - stone young chemical analysis, specific anomaly of ore elements do not show maker.
11 - Field dependence of the small acidic intrusive and epithermal mineralization, and intensity of hydrothermal soLoutions related to performance in Late Miocene and Pliocene is marked, so that all regional and travertine and silica wide range of the mass influence can be seen, but some within the volcanic rocks are widespread, according to the volume of alteration of volcanic rocks not significant.

The model reproductive Takab area deposits

Considering what was said, the middle portion of the rectangular Takab Late Oligocene to the beginning of Quaternary, magmatic activity have been very severe and it works as diverse volcanic rocks of rhyolite to basalt and tuff, and associated small intrusive gabbro to alkali granite is changing.

The magmatic activity, hydrothermal activity lead to more serious is that it works and still not ended as hot springs and boiling springs to instrument can be seen.
Melting parts of the Precambrian basement - Cambrian rocks, and interference in younger magmatism (crustal magma and mixing with mantle Magmahay) and thermal gradient climbing in them (which weakened graft incompatible elements in old rocks) hydrothermal soLoutions and spin (derived from igneous rocks, metamorphic rocks rainfall) with ore elements in rocks and fracture mechanisms and the existence of suitable traps absorbed elements of the instrument have ore, lead deposits have been focused.

In this respect, the young deposits Takab region can be divided into two categories:

1 - Ay deposits Castle C, Moghanlu, Horn Horn mercury, lead around him. The age of the young mineral deposits and signs of basement ore significant role, is of special importance.
2 - Multiple metal deposits particularly nickel and cobalt mineralization, copper Tataqshlaqy signs and symptoms to fresh copper. Thermal deposits are among the high-temperature hydrothermal soLoutions related to them, of andesitic volcanic rocks have originated. Temperature of the deposits formed above basement epithermal role in their formation is less important.



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