Mojgan Zarei Nejad
Head of GIS group-Geological Survey of Iran
Email : [email protected]
Today Ine witness the increasing expansion of technology and the world information system. The Geographic Information System (GIS) is amony those information systems which has had spectacular progress in the last decade. Geographic Information System is a single terminology to express a deep, and vast concept Geographic Information System is mainly a computrized technology including hardware, software and expeciallized man power which has been appeared in last decades for obtaining , organizing , interpreting and finally designing and producing different modles and at the present time it is developing. The main factor which makes this technology different from the other reserve and recovery system is in repect to the geograhical location.
Considering this specification, the Geographic Information System is as modern technology, has been changed to efficient industry for interpreting the qualitative and quontitative data an designing the former geographic images. Among the other users ot Geographic Information System is geology branch. Geological interpretation in one area, wether it is used for mineral and oil exploration or for engineering geological studies, principally is a compound process of various data.
In order to face with rapid growth of digital spatial in geoscience
The geoscientists need to understand the spatial relation among the various spatial data. the exsistance of Geographic Information System is very important and fundamental. Geographic Information System has created spectacular change in many applied branches , because it will make the processing and interpretting separate layers of spatial data possible and provides methods for interpreting and modeling for the interlayers.
The geologist or explorer, linking different geological data , will seek for useful geological structure in an area. All geological data, in order to be fruitful and productive, should be interpreted considering their geographic locality. Geographic Information System, Providing presentation facilities and simutanous data interpretation, enables the geologist or explorer to prepare mineral potential maps with various data more quickly and precisely, which was impossible to be carried out with analogue and traditioal methods. Geographic Information System is used for making decision for those Geological Survey of Iran’s Projects which are based on spatial data. Cartographic application of GIS in collecting , digitalizing and preparing different scale geological maps and in national scale (geological, air borne geophysic, mineral , geomorphology maps and etc.) are among the main application of GIS for the numerous geoscientists. (Figs : 1 , 2)
Figure 1 Geomorphological map of Iran
Figure 2 Metalogenic map of Iran
The great amount of mineral deposits are not exposed on the surface and they are laid in lower layers. To Know about the upper layers, making use of Geographic Information System methods we can find out about their probable exsistance. In this way in exploration affair, in order to montage the data, as mineral potential map we can make use of Geographic Information System for making decision for future exploration priorities. Mineral exploration is a multi stage process which begins from small scale and change to large scale and then ends to choosing promising area for exploration in order to reach the mineral deposits. (Fig 3)
Figure 3 Integration data of Takht-E-Solyman sheet (North-West of Iran)
In engineering geology, dip stability conditions and erosion state with Geographic Information System can be considered as best solution in development and mineral projects (Fig 4)
Figure 4 Land slide hazard map of Takht-e-Solyman sheet
Geochemist, making we use of Geographic Information System, can define and draw the drainge basin area and obtian the bed rock of the collected samples or study spatial correlation among celenium distribution in the surficial water and distribution of local rocks.
Geophysitst, uses Geographic Information System For studying the spatial Factors related to earthquakes and defining shallow intrusive bodies in different scales considering the fligh height and space (Fig 5)
Figure 5 Geophysical map of Iran
In economic geology, the Geographic Information System can be used for zoning the mineral exploration and preparation digital economic geological maps including complete mines data and indices (type , coordinations, pargenesis, age, species, country rock the shape of mineral ore) and also it can be helpful in designing exploration model , finding out whether the ore deposit is econimical or not and tracing new exploration location by making mineralization models.
Optimised use of underground mineral resources of the country will have substontial and main role in creating balance and establishing relatively economic self-sufficiency policy and consequently political and economical dependence. On the other hand , if our potential in recognition and row materias exploration as well as exploitation and processing , using Geographic Information System, increases it will couuse the added volue in mining section and incrcase its share in the national Gross product (NGP) , it will also Facilitate and expand the employment.
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