Exploration of bitumen in West Gilan is important in that the region is located in the folded Zagros.
Remote sensing data (satellite images), geological, tectonic and mineral data sets of the region are used in the preparation of an innovative integrated algorithm for the exploration of Gilsonite mineral in the early stages of exploration.
It should be noted that the Gilsonite Mad mine uses all exploration methods.
Criteria and sub-criteria effective in the exploration of this mineral are identified and evaluated according to the available exploration data.
These criteria are then ranked using the fuzzy analytic hierarchical process, weighting, and finally using the method most similar to the positive and negative ideal solution in the fuzzy environment to prepare the Gilsonite mineral potential mapping map in West Gilan region. To be.
Finally, a mineral potential map is generated using a combination of the above methods for optimal identification in the early stages of exploration of this valuable mineral to reduce the time, cost and risk of exploration.
Due to the fact that bitumen mineral is a strategic material in the world and in Iran, the exploration of Gilsonite deposit is a high priority, the exploration of new reserves in potential areas is the main goal of identifying and searching for minerals.
For this purpose, a set of exploratory data must be collected and finally obtained by analyzing and integrating them.
1- In the first phase, the goal is to identify and determine effective criteria for exploration of bitumen mines
2- Then in the second phase, FAHP was used to obtain the weight of criteria and sub-criteria
3- Finally, in the third phase, FTOPSIS was used to rank areas with more potential.
It should be noted that MCDM and MPM can be done using FAHP, but this process can be improved if integrated with other decision making methods.
The mineral bitumen reaction zone, like the Gilsonite Mad mine, is mainly located in the West Gilan region, which is one of the most prone areas in Iran for Gilsonite exploration. This zone is structurally located in the folded Zagros region, whose eastern parts are part of the Lorestan sedimentary basin and its western part is part of the northern Dezful sedimentary basin.
In terms of hydrocarbon potential, the study area includes surface and deep potentials whose surface potential is mainly gilsonite.
Gilsonite is a natural hydrocarbon that is physically and chemically in the range between refinery bitumen and coal.
Most of the known hydrocarbon resources in West Gilan region are related to faults in the region. In identifying and exploring the potential of Gilsonite, the study of fold processes, faults, fractures and their formation mechanism is of particular importance. In this area, anticlines are the main structures for mineral accumulation, especially Gilsonite.
The next stage is an important and abundant factor, faults and fractures that control the location of the mineral in different thicknesses.
In general, effective data in Gilsonite exploration include stratigraphy, mineralization, and tectonics. Geological maps 50,000: 1 National Iranian Oil Company is used to extract stratigraphic and tectonic data.
Also, thermal image propagation and reflection radiometer (ASTER) have been used to determine the boundaries of formations and improve stratigraphy and tectonics.
Next, the data used in geology, reservoir rocks and rock cover control the oil systems in the Zagros.
Formations are quite mature in all regions of Lorestan, and Asmari and Gachsaran formations include a good cover of petroleum products of Pabdeh origin.
This is a stone unit that includes a tank and paving; The largest area is in the West Gilan region.
Such factors have caused, in addition to other sources and reservoirs of the Zagros Belt, the West Gilan region to be one of the richest regions in the Middle East in terms of shallow reservoir characteristics, near the surface and outflow of hydrocarbons, especially Gilsonite mineral.
The best host of Gilsonite mineralization (in terms of storage and quality) in West Gilan region is Gachsaran Formation. Also, the anhydritic part of Kalhor member as well as Asmari, Pabdeh and Gurpi formations rarely have weak mineralization.
Bitumen mines in this area are generally located in the northwest-southeast trend and parallel.
Gilsonite minerals in Pabdeh Formation have mainly low reserves and high quality along transverse fractures.
3- and joints
These features have been extracted from geological maps of 50,50: 1 West Gilan region.
According to experts in the field of mineral exploration, longitudinal faults are more important than transverse faults.
Although faults and fractures are less common in the region than creases, they are very important because of controlling mineral dispersion.
In parts of the zone where Pabdeh and Gurpi formations have a significant expansion due to the ductility characteristics of these formations on the one hand and on the other hand the extensive outcrops of Gachsaran Formation in the zone, has caused rupture at the surface to be minimized and faults seen at the surface to be low. It should be deep and short in length, and should not exceed Aghajari and Gachsaran formations.
Mineralization Due to the fact that in this exploration zone, there are large and small Gilsonite mines. The layers created by these mines have exploratory value.
Mines due to the importance and impact Gilsonite exploration is classified into three layers including large mining layer, small mining layer and exploration indices.