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Geochemistry Group

The main goal of the Geochemistry Dept
Geochemical information is considered as one of the main information layers for introducing mineral promising areas. The five information layers are consisted of geological maps, satellite information, hummer prospecting geochemical-heavy minerals maps and remote sensing information.
These information as the main data are integrated in the GIS Dept. And finally the promising areas are introduced. The geochemical-heavy mineral information layer is among the most prominent data in information layers, the major goal of which, is introducing anomaly and potential mineralization areas. Sampling Network Design Sampling network design is carried out on the basis of exploration project scale on 1:100/000 scale (Regional) the sampling network design is done for geochemical and heavy mineral samples on 1:2000 scale (semi-detailed), the sampling network can be designed both for stream sediments (more dense) and for rock or soil. In larger scale (detailed), sampling network is designed for collecting samples from primary places (soil and rock) and also for small wells, trenches and boreholes as well.
To design the sampling network, different information are used such as the results of previous work, geological, topography and airborne geophysical maps and satellite data. Sampling and sample preparation Sampling on 1:100/000 scale map sheets (Regional) up to semi-detailed is done by two methods: Collecting geochemistry and heavy mineral samples.
In detailed phase, the sample, which are collected from soil and rock go under preliminary preparation by the GSI specialized geochemists. Some part of this work is done at the GSI lab and the samples are crushed into 200mesh powder. All samples are labeled by special code indicating date of sampling, name of the topographic map and etc. Data Processing All data obtained by analytical instruments for geochemical and heavy mineral samples go under univariable and multivariable processing using special software such as Data, Spss, Statistica, Mine.
Finally anomaly maps for different variants are presented as uni and multi variable maps. Geochemical-heavy mineral maps are separately presented in this phase. Drawing Anomaly Maps After data processing and determining anomalies for geochemical and heavy mineral data, the anomaly maps, using Auto Cad, Sufer software, are drawn up. The prepared maps are the guide and key of the next work such as explanation of geochemistry-heavy mineral anomalies, interpretation, evaluation of anomaly area and finally the suggestion are given.
These maps are presented fully colored (6 colors). All needed information such as color index; anomalies grade range and etc… are included. Anomalies Control and Introducing Promising Areas The anomalies, which have been obtained by geochemical and heavy mineral exploration methods, are fully evaluated in the field and the accuracy and precision is carefully checked. Evaluation of anomaly areas is considered as the last phase of a geochemistry report, in which promising areas are introduced. In proposed, areas, anomaly control is resulted to obtaining new mineralization, expansion of alteration or in some cases is correlated with ancient mines work.
Integrating geochemical-heavy mineral data and field observation concluded in introducing promising areas. These areas are sometimes confirmed by geochemical studies method and in some cases by heavy mineral studies and sometimes by applying both methods. In some cases, the field observations itself well help to recognize the mines traces: Researches Research and study about the up-to-date exploration methods is among the most important objectives of this group.
Applying modern exploration methods leads to exploration new ore deposits and identification of mineral potential areas. Training Training is divided into two parts. To give training to the students who are introduced by the universities and higher education institutes, which are done under supervision of the geochemistry group. To give training to the experts who are working at the GSI in order to upgrade the level of their knowledge.
However, it is to be noted that educational activities are among the extra curricular programme of this group. Implementation of Semi-detailed and Detailed Projects In some cases, those mineral promising areas introduced by the specialists of this exploration group in Regional Exploration are designed to go under semi-detailed and detailed exploration phases.
As examples Titanium Semi-detailed Exploration project in Dargaz and Bag-e-Kahnuj (southeast Iran), the Semi-detailed to Detailed Gold Exploration Project in Arghash area (northeast Iran), Semi-detailed to Detailed Gold Exploration Project in Moalleman (east Iran) and Semi-detailed to Detailed Exploration Project in chalkuhian, (northwest Iran), are among the Implementation projects. Environmental Geochemistry Today, the complicated and serious issue of environment is considered as one of the administrators, challenges. Pollution of surface runoff and ground water by civil and industrial units, contamination of springs by heavy minerals, agricultural infusion polluted by chemical agents and garbage are the issues which are jeopardizing the environment.
During the recent years a group has been defined, titled environmental geochemistry group, to study about the pollutants agents and assessing pollution rate coming out of mineral activity and related industries.


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