استفاده از روش فرکتالی طیف توان در تهیه نقشه های آنومالی ژئوشیمیایی کانسار طلا- آنتیموان ساری گونای کردستان

نوع مقاله: علمی-پژوهشی

نویسندگان

1 استادیار گروه مهندسی معدن، دانشگاه صنعتی بیرجند، بیرجند

2 دانشیار دانشکده مهندسی معدن، دانشگاه صنعتی اصفهان، اصفهان

چکیده

تفکیک الگوهای ژئوشیمیایی که به صورت غنی‌شدگی- تهی‌شدگی عناصر، خود را نشان می‌دهند، یکی از مسایل مهم در تفسیر داده‌های ژئوشیمیایی محسوب می‌شود. استفاده از روش فرکتالی طیف توان به دلیل انتقال داده‌ها از حوزه مکان به فرکانس، امکان تفکیک چنین داده‌هایی را میسر می‌سازد. با پیاده‌سازی الگوریتم طیف توان- مساحت بر روی نتایج آنالیز طلا و آنتیموان نمونه‌های ژئوشیمیایی محیط خاکی در منطقه اکتشافی ساری‌گونای، برای هر عنصر سه نقشه‌های نویز، آنومالی و زمینه تهیه شده است.داده‌های نقشه‌های نویز معادل 5 تا 6 درصد دامنه تغییرات داده‌های اولیه را شامل شده است و نشان‌دهنده‌ خطاهای نمونه‌برداری و آنالیز و تغییرات سریع ناشی از توزیع عناصر در سنگ‌های مختلف است. نقشه‌های آنومالی که دامنه تغییرات آن مشابه دامنه تغییرات داده‌های اولیه است، نشان‌دهنده‌ مکان‌های با عیارهای بالا و موقعیت دقیق آنومالی ژئوشیمیایی سطحی است. درحالی که نقشه‌های زمینه که حدود 12 تا 18 درصد دامنه تغییرات داده‌های اولیه را شامل می‌شوند، نشان‌دهنده‌ روند کلی تغییرات عیار در منطقه مطالعاتی و موقعیت تقریبی آنومالی ژئوشیمیایی است. از نقشه آنومالی که مرکز کانی‌زایی را نشان می‌دهد برای طراحی حفاری‌های اولیه و از نقشه زمینه که محدوده کانی‌زایی را نشان می‌دهد برای طراحی شبکه حفاری در فازهای اکتشافی مقدماتی و تفصیلی می‌توان استفاده کرد.  نقشه‌های آنومالی و زمینه نواحی کانسار ساری‌گونای، آق‌داغ و یک ناحیه جدید را برای اکتشاف طلا و نواحی کانسار ساری‌گونای، آق‌داغ و محدوده گسل بین دو کانسار را برای اکتشاف آنتیموان پیشنهاد کرده‌اند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Application of Power Spectrum Fractal Method to Model Geochemical Anomalies in Sari Gunay Epithermal Au-Sb Deposit, Kordestan Province

نویسندگان [English]

  • H. Geranian 1
  • S.H. Tabatabaei 2
1 Assistant Professor, Dept. of of Mining Engineering, Birjand University of Technology, Birjand, Iran
2 Associate Professor, Dept. of Mining Engineering, Isfahan University of Technology, Isfahan, Iran
چکیده [English]

Identification of geochemical anomaly patterns, which indicate the enrichment and depletion of elements, is an important issue in the interpretation of geochemical data. The use of the power spectrum-area fractal method allows the better separation of geochemical populations that is due to transformation of the data from spatial domain to frequency domain. By implementing this method on the dataset of Au and Sb element contents obtained from chemical analysis of soil samples taken Sari Gunay exploration zone, three models including noise, anomaly and background maps were prepared for each element. The data of the noise maps constitute 5-6 percent of the primary data variation range and indicate sampling and analysis errors and rapid changes due to the distribution of elements in different rocks. Anomaly maps those variation range is similar to the variation range of initial data, represent enrichment locations and precise positioning of surface geochemical anomalies. However, background maps that cover about 12-18 percent of the variation range of primary data indicate the general trend of the concentration variations in the study area and the approximate location of geochemical anomalies. Anomaly map that shows the mineralization centre can be used to design a preliminary drilling network and the background map that shows the mineralization area, can be used to design drilling network in preliminary and detailed exploration phases. Anomaly and background maps have proposed Sari Gunay and Agh Dagh deposits areas and a new area for gold exploration. Besides, they have suggested Sari Gunay and Agh Dagh deposits areas and the fault area between two deposits for antimony exploration.

کلیدواژه‌ها [English]

  • Fractal modelling
  • Power spectrum
  • Geochemical anomaly
  • Filtering of geochemical maps
  • Sari Gunay epithermal gold deposit
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