نوع مقاله : مقاله پژوهشی
نویسندگان
1 بخش استخراج، دانشکده معدن و متالورژی، دانشگاه یزد، صندوق پستی: ۸۹۱۵۸۱۸۴۱۱، یزد - ایران
2 بخش اکتشاف، دانشکده معدن و متالورژی، دانشگاه یزد، صندوق پستی: ۸۹۱۵۸۱۸۴۱۱، یزد - ایران
چکیده
روش الکتریکی به عنوان یک بررسی ژئوفیزیکی می‌تواند پارامترهای زمین‌شناسی شامل خردشدگی، شاخص دگرسانی توده سنگ، درصد اشباع، کیفیت آب زیرزمینی و . . . را به خوبی نمایش دهد. این پارامترها نقش مهمی در طبقه‌بندی مهندسی توده سنگ از طریق تأثیر بر دو شاخص کیفیت توده سنگ (RQD) و شاخص مقاومت زمین‌شناسی (GSI)، کانه‌زایی عناصر و نیز نحوه حفاری دارند. در این مقاله با استفاده از روش سونداژ الکتریکی قائم در لایه‌های زیرسطحی به بررسی تعیین این پارامترها و متعاقباً دو شاخص مذکور در توده‌سنگ‌های آذرآواری آنومالی III کانسار ناریگان پرداخته شده است. نتایج نشان می دهد که مقاومت ویژه الکتریکی تفسیر شده (با استفاده از نرم‌افزار win2IPI) ارتباط قابل قبولی با میزان شاخص دگرسانی و تا حدی GSI در توده سنگ دارد. با این حال تعیین دقیق GSI و هم‌چنین RQD با استفاده از این روش ژئوفیزیکی از اعتماد بالایی برخوردار نیست. به بیان سادهتر با استفاده از یک رابطه ریاضی نمی‌توان با مقاومت ویژه الکتریکی میزان GSI و شاخص آلتراسیون را تخمین زد.
کلیدواژه‌ها
عنوان مقاله [English]
The application of vertical electrical sounding in geomechanical recognition of host rock mass of anomaly III of Narigan deposit, Bafgh region, Central Iran zone
نویسندگان [English]
- S.H. Beheshti Bafqi 1
- A.R. Yarahmadi Bafqi 1
- A. Gorbani 2
- H. Gari 2
1 Department of Mining and Metallurgy, Extraction Faculty, Yazd University, P.O.BOX: 8915818411, Yazd - Iran
2 Department of Mining and Metallurgy, Exploration Faculty, Yazd University, P.O.BOX: 8915818411, Yazd - Iran
چکیده [English]
The electrical method as a geophysical survey can show the geological parameters including fragmentation, rock mass alteration index, saturation percentage and groundwater quality. These parameters play an important role in rock mass engineering classification by affecting the rock mass quality design (RQD) and geological strength index (GSI), mineralization of elements and drilling method. In this paper, using the vertical electrical sounding method in subsurface layers, the determination of these parameters and subsequently two mentioned indicators in anomalous III pyroclastic rock masses of Narigan deposit was investigated. The results showed that the interpreted electrical resistivity (using IPI2win software) has an acceptable correlation betweem the degree of alteration index and GSI in the rock mass. However, accurate determination of GSI and RQD using this geophysical method is not very reliable. In other words, using a mathematical equation, it is not possible to estimate the amount of GSI and the alteration index with the electrical resistivity.
کلیدواژه‌ها [English]
- Vertical electrical sounding
- Rock mass engineering classification
- Altration index
- GSI
- RQD
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