Application of RQD-number and RQD-volume multifractal modelling to delineate rock mass characterisation in Kahang Cu-Mo porphyry deposit, central Iran

• Autorzy: Yasrebi A. B. , Wetherelt A. , Foster P. J. , Afzal P. , Coggan J. , Ahangaran D. K.

Warianty tytułu

PL

Zastosowanie metod modelowania numerycznego oraz modelowania fraktalnego do analizy jakości skał w celu określenia charakterystyki górotworu w obszarze złoża Cu-Mo w Kahang, środkowy Iran

• Języki publikacji: EN

Abstrakty

EN

Identification of rock mass properties in terms of Rock Quality Designation (RQD) plays a significant role in mine planning and design. This study aims to separate the rock mass characterisation based on RQD data analysed from 48 boreholes in Kahang Cu-Mo porphyry deposit situated in the central Iran utilising RQD-Volume (RQD-V) and RQD-Number (RQD-N) fractal models. The log-log plots for RQD-V and RQD-N models show four rock mass populations defined by RQD thresholds of 3.55, 25.12 and 89.12% and 10.47, 41.68 and 83.17% respectively which represent very poor, poor, good and excellent rocks based on Deere and Miller rock classification. The RQD-V and RQD-N models indicate that the excellent rocks are situated in the NW and central parts of this deposit however, the good rocks are located in the most parts of the deposit. The results of validation of the fractal models with the RQD block model show that the RQD-N fractal model of excellent rock quality is better than the RQD-V fractal model of the same rock quality. Correlation between results of the fractal and the geological models illustrates that the excellent rocks are associated with porphyric quartz diorite (PQD) units. The results reveal that there is a multifractal nature in rock characterisation with respect to RQD for the Kahang deposit. The proposed fractal model can be intended for the better understanding of the rock quality for purpose of determination of the final pit slope.

PL

Identyfikacja właściwości górotworu odgrywa zasadniczą rolę w planowaniu wydobycia i projektowaniu kopalni. Praca niniejsza ma na celu określenie charakterystyki górotworu w oparciu o dane o jakości skał zebrane na podstawie próbek uzyskanych z 48 odwiertów wykonanych w złożu porfiru Cu-Mo w Kahang, zalegającym w środkowym Iranie przy użyciu modeli fraktalnych RQD-V - Rock Quality Determination-Volume [Określenie jakości skał-objętość]) i RQD-N (Rock Quality Determination-Number [Określenie jakości skał-liczba]). Wykresy logarytmiczne wykonane dla modeli RQD-V i RQD-N wykazują istnienie czterech populacji warstw górotworu, określonych na podstawie parametrów progowych: 3.55; 25.12; 89.12% oraz 10.47; 41.68 i 83.17%, odpowiadającym kolejno stopniom jakości: bardzo słaby, słaby, dobry i bardzo dobry, zgodnie z klasyfikacją skał Deere i Millera. Wyniki uzyskane przy zastosowaniu modeli RQD-V i RQD-N wskazują, że najlepsze skały zalegają w północno- zachodniej i centralnej części złoża, z kolei dobrej jakości skały znaleźć można w obrębie całego złoża. Walidacja modeli fraktalnych w oparciu o model blokowy (RQD block model) wskazuje, że model RQD-N dla bardzo dobrej jakości skał jest skuteczniejszy niż model RQD-V dla tej samej jakości skał. Wysoki stopień korelacji pomiędzy wynikami uzyskanymi w oparciu o modele fraktalne i geologiczne pokazuje, że najwyższej jakości skały związane są z obecnością porfirowego diorytu kwarcowego. Badanie wykazuje fraktalną naturę charakterystyki jakości skał w złożu Kahang. Zaproponowany model fraktalny wykorzystać można do lepszego poznania zagadnienia jakości skał w celu obliczenia nachylenia wyrobiska.

Słowa kluczowe

EN

RQD; porphyric quartz diorite; Central Iran

PL

określenie właściwości górotworu; modele fraktalne RQD-V i RQD-N; złoże porfiru Cu-MO w Kahang; porfirowy dioryt kwarcowy; środkowy Iran

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2013
• Tom: Vol. 58, no. 4
• Strony: 1023--1035
• Opis fizyczny: Bibliogr. 43 poz., rys., tab., wykr.

Twórcy

autor

Yasrebi A. B.

• Camborne School of Mines, University of Exeter, Penryn, UK

autor

Wetherelt A.

• Camborne School of Mines, University of Exeter, Penryn, UK

autor

Foster P. J.

• Camborne School of Mines, University of Exeter, Penryn, UK

autor

Afzal P.

• Department of Mining Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran

autor

Coggan J.

• Camborne School of Mines, University of Exeter, Penryn, UK

autor

Ahangaran D. K.

• Camborne School of Mines, University of Exeter, Penryn, UK

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