Chatree Gold Mine
Akara Mining Limited
Paleo-Stress Evolution in the A and K-East Pits of Chatree Gold Mine, Phichit-Phetchabun Provinces,
Central Thailand
Worawong Sirisookprasert 1, Sarawute Chantraprasert 2
and Suphanit Suphanunthi 1
1 Akara Mining Limited 2 Department of Geological Sciences, Chiang Mai University
Kinematic & Dynamic Analyses Using FaultKin® 4.3 by Allmendinger, R.W., Marrett, R.A., and Cladouhos, T.
Topic
Introduction
Problem
Methodology
Result
Conclusion & Discussion
Application
Chanthaburi
Sra Kaew Bangkok CAMBODIA
THAILAND
THE LAO PEOPLE’S DEMOCRATIC REPUBLIC
VIETNAM
THE UNION OF MYANMAR
Loei
Phetchabun
Nakhon Sawan
Tak
Nan
Phrae
Chiang Rai
Chaing Mai
Lampang
98oE 102oE 106oE
12oN
16oN
20oN Chiang Khong
Phai Sali
0 100 200km
Li
Chiang Rai – Chiang Mai volcanic belt Chiang Khong – Tak volcanic belt
Sra Kaew – Chanthaburi volcanic belt volcanic belt
Loei – Phetchabun – Nakhon Nayok volcanic belt
Nakhon Nayok
Lamphun
Mae Ping Fault Zone
N
Nan - Uttaradit volcanic belt
Uttaradit
Mae Hong Son
Mae Sariang
Portions of any volcanic belt to the north
Mae Sariang Fault Zone
Modified from Kosuwan, 2004 and Panjasawatwong, et al, 2006
Chatree Gold Mine
Introduction
A Pit
K-East Pit
Geology & Problem
N10E / 80NW : RL / LL look NW
Superimposed Structure
Selected 84 fault slip data from 2,000 structural data for kinematic & dynamic analyses.
Problem
Methodology
Kinematic Analyses Changes in Dimension of Rock Body after Fault Movement
Kinematic Axes Plot
Four Fault Sets & Two Tectonic Mechanism with
Distinct Kinematic Axes
Extension Mechanism 1.1 Extension 1.2 Conjugated Extension
Compression Mechanism 2.1 Conjugated Compression (inverse) 2.2 Compression
NNW-SSE trending (N20W/50E) Normal Fault
Extensional Fault
Field evidence of fissure quart - carbonate - chlorite banded vein intrude along with normal fault plane.
FAULTS & STRIAE (n=22) arrow shows the movement of the hanging wall
Shortening (P) Axis
Extension (T) Axis
Maximum Principal Stress
Intermediate Principal Stress Minimum Principal Stress
1
2
3
The stereographic plot shows pre-mineralized NNW-SSE normal fault present ENE-WSW extension mechanism.
Andesitic dyke crosscut in damage zone (stockwork replaced on hanging wall of normal fault)
Extension Tectonic Mechanism
1
2
3
Pre-mineralized extensional stage is represented as NNW-SSE trending normal fault plane on great circles with scattering sub-horizontal extension kinematic axes (T) and sub-vertical shortening kinematic axes (P). They indicate ENE-WSW extension and generate NNW-SSE trending pre-mineralized normal faults.
N=22
Shortening (P) Axis
Extension (T) Axis
Maximum Principal Stress
Intermediate Principal Stress Minimum Principal Stress
1
2
3
Field evidence of fissure quart - carbonate - chlorite banded vein intrude along with normal fault plane.
FAULTS & STRIAE (n=22) arrow shows the movement of the hanging wall
Shortening (P) Axis
Extension (T) Axis
Maximum Principal Stress
Intermediate Principal Stress Minimum Principal Stress
1
2
3
The stereographic plot shows pre-mineralized NNW-SSE normal fault present ENE-WSW extension mechanism.
Andesitic dyke crosscut in damage zone (stockwork replaced on hanging wall of normal fault)
Field evidence of fissure quart - carbonate - chlorite banded vein intrude along with normal fault plane.
Andesitic dyke crosscut in damage zone (stockwork replaced on hanging wall of normal fault)
Extension Tectonic Mechanism
Conjugated Extension
Tectonic Mechanism
1
2
3
Post-mineralized Extensional Mechanism The E-W trending left lateral faults were crosscut by andesitic dykes and were closely associated with two extensional conjugate sets of steeply dipping strike-slip and oblique faults with scattered shortening (P) and extension (T) kinematic axes. they correspond to N-S trending sub-horizontal maximum principal stress (σ1) and E-W trending sub-horizontal minimum principal stress (σ3).
N=30
Shortening (P) Axis
Extension (T) Axis
Maximum Principal Stress
Intermediate Principal Stress Minimum Principal Stress
1
2
3
T A
Right Lateral Fault (N50W / 70NE)
cross-cutting in andesitic Dyke
(N20E / 85NW)
Look SW
Conjugated Extension
Tectonic Mechanism
Younger conjugate compressional fault set crosscutting relationship of younger NE-SW trending dyke intruded along of NW-SE trending left-lateral and NNE-SSW trending right-lateral strike-slip faults. The scattered plot of shortening and extension kinematic axes present ENE-WSW trending sub-horizontal maximum stress (σ1) and sub-vertical minimum stress (σ3) represented E-W compressional tectonic mechanism.
1
2
3 N=28
Shortening (P) Axis
Extension (T) Axis
Maximum Principal Stress
Intermediate Principal Stress Minimum Principal Stress
1
2
3
Conjugated Compression
Tectonic Mechanism
Late NE-SW dyke crosscut older NE-SW & NW-SE trending dykes
Conjugated Compression
Tectonic Mechanism
Shortening (P) Axis
Extension (T) Axis
Maximum Principal Stress
Intermediate Principal Stress Minimum Principal Stress
1
2
3
The E-W compressional tectonic mechanism was
generated to the latest NNW-SSE trending complicated reverse faults present ENE-WSW trending sub-horizontal maximum principal stress (σ1) with N-S trending sub-vertical minimum principal stress (σ3).
N=4
Compression
Tectonic Mechanism
Conclusion • Outcrop evidence was used to determine the timing and
relationship of the faults to mineralization and regional tectonics.
• NNW-SSE trending normal faults developed in response to E-W extension prior to or during mineralization in the Early Triassic(ca. 250 Ma). Back-arc extension?
• Transient stress systems during the transition between extension to compression resulted in two sets of conjugate strike-slip faults associated with andesitic dyke intrusion (ca. 244 Ma).
• N-S trending reverse faults were likely related to Triassic collision.
Application
H Pit & Gosowong Comparisons Model
H-central & cutback
H-west & J
Look SW
Application
Released face-1 : J1 (85/225)
Released face-2 : J2 (85/135)
3D Solid Model By Surpac Software
Geological & Geotechnical Pit Mapping
Akara Environmental Care Mining
Toward - Sustainable
On Resource & Production