Geological and Mineral Prospecting in the Kuala Kelawang
area using Remote Sensing and GIS Tecniques
Result and Discussion
In the primary forest covered area such as Kuala Kelawang areas, conclusion of geological stud and digital processing techniques can be combined with visual interpretation and GIS. Each technique of digital processing will give some separated information. Band Composite imagery with selected bands and difference color (357 and 457) and filtering techniques is useful to enhance the lithological unit and tectonic features. Principal Components is also useful for delineate lineament (PC1) and lithological unit (PC3, PC4). With difference data from digital process, the visual interpretation brought out more detail information compare to the result from one kind of image. The correlation matrix between bands of Landsat TM (especially bands 4, 5, 7) was also used to minimize the differents of digital counts in each band which related to the same physical units.
In the digital processing methods, most of the spectral images have shown their own distinctive feature of geological structure in the study area. For example of B1/B3 displayed more detail of alluvial formation along the rive system. Whereas image of B3/B7, the different between granite Telemong and Paleozoic Sandstone can be delineated into contour line based on the processing of different band and band ratio the DN value of rock types have been identified as shown in Table 1. In the study area, except the basin area, the raw data or even after stretching process, the imagery has show most of the hilly and mountain area was fully covered by tropical forest. Spectral characteristic of rock has been identified by vegetable reflectance using filtering technique, and a number of lineament has been enhanced. Result of filtering technique shows mainly five generation of lineament which has been distinguished using edge enhancement, Laplacian filter, Suvillivar filter, and Bernsteia filter (3x3) with different direction).
Table 1: DN value of rock types in different images
| |
|
G5mf |
G5C |
G(1,2,3,4) |
P2 |
C |
S-D |
Q |
W |
| B1 |
255 |
64 |
64 |
67 |
72 |
67 |
69 |
90 |
70 |
| B2 |
133 |
24 |
23 |
26 |
32 |
27 |
29 |
70 |
41 |
| B3 |
250 |
26 |
24 |
22 |
38 |
26 |
48 |
67 |
50 |
| B4 |
153 |
85 |
98 |
93 |
83 |
90 |
82 |
110 |
14 |
| B5 |
243 |
50 |
76 |
53 |
53 |
12 |
79 |
96 |
15 |
| B7 |
131 |
8 |
14 |
9 |
23 |
20 |
27 |
50 |
3 |
| B1/B2 |
1.92 |
2.67 |
2.78 |
2.35 |
2.25 |
2.48 |
2.40 |
1.29 |
1.71 |
| B1/ B3 |
1.02 |
2.46 |
2.46 |
2.78 |
1.89 |
2.58 |
1.44 |
1.34 |
1.40 |
| B1/ B7 |
1.95 |
8.00 |
4.57 |
6.78 |
3.13 |
3.35 |
2.56 |
1.80 |
2.30 |
| B2/ B3 |
0.53 |
0.92 |
0.95 |
1.18 |
0.84 |
1.03 |
0.60 |
1.04 |
0.80 |
| B2/ B4 |
0.87 |
0.24 |
0.23 |
0.28 |
0.38 |
0.30 |
0.35 |
0.64 |
2.93 |
| B2/ B5 |
0.55 |
0.48 |
0.30 |
0.49 |
0.60 |
0.38 |
0.37 |
0.73 |
2.73 |
| B2/ B7 |
1.02 |
3.00 |
1.64 |
2.89 |
1.39 |
1.35 |
1.07 |
1.80 |
13.7 |
| B3/ B4 |
1.63 |
0.31 |
0.24 |
0.24 |
0.46 |
0.36 |
1.14 |
0.61 |
3.57 |
| B3/ B5 |
1.03 |
0.52 |
0.32 |
0.41 |
0.72 |
0.36 |
0.60 |
0.70 |
33 |
| B3/ B7 |
1.90 |
3.25 |
1.17 |
2.40 |
1.65 |
1.30 |
1.78 |
2.20 |
4.67 |
| B5/ B1 |
0.95 |
0.78 |
1.18 |
0.87 |
0.74 |
1.07 |
1.14 |
1.07 |
0.21 |
| B5/ B2 |
1.83 |
2.08 |
3.30 |
201 |
1.65 |
2.67 |
2.72 |
1.37 |
0.36 |
| B5/ B3 |
0.97 |
1.12 |
3.16 |
2.41 |
1.39 |
2.77 |
1.65 |
1.43 |
0.30 |
| B5/ B7 |
1.85 |
6.25 |
5.42 |
0.57 |
2.30 |
3.60 |
1.44 |
1.92 |
5.00 |
| B4/ B5 |
0.63 |
1.70 |
1.29 |
1.75 |
1.57 |
1.25 |
1.04 |
1.14 |
0.93 |
| B4/ B7 |
1.17 |
10.63 |
7.00 |
10.33 |
3.60 |
4.50 |
3.04 |
2.20 |
4.67 |
| B4/ B1 |
0.60 |
1.33 |
1.53 |
1.52 |
1.15 |
1.34 |
1.19 |
1.22 |
0.20 |
| B7/ B3 |
0.52 |
0.3 |
0.58 |
0.41 |
0.60 |
0.77 |
0.56 |
0.75 |
006 |
| B7/ B4 |
0.86 |
0.09 |
0.14 |
0.10 |
0.28 |
0.22 |
0.33 |
0.45 |
0.21 |
| B7/ B5 |
0.54 |
0.16 |
0.18 |
0.17 |
2.30 |
3.60 |
2.90 |
0.52 |
0.20 |
| B1/ B5 |
1.05 |
1.28 |
0.84 |
1.15 |
1.36 |
0.93 |
0.87 |
0.94 |
4.67 |
The main direction of lineament are Northeast-Southeast, North-South, Northeast-Southwest and East-West. The Northwest-Southeast is the earlier than Northeast-Southwest direction. High frequency filtering is used because it is a suitable technique for differentiate the boundary of several coarse and medium grained Granitic Zones, which also concerning the different of crystallization of biotite, muscovite, amphybolite, and tourmaline; especially in Bentong Granite distribution. Circular structure has been clearly delineated in the edge enhancement imageries and in the contrast enhancement image. Small circular structures with diameter ranging from 1-2 km are closely related to the mineral concentration position in the Semenyih Granitoid (G4) and Broga Granite (G2) (Shu, 1989). In the principal component analysis part, the eigen vector is changed due to the spectral of rock types in different wavelength on the image of PC1, PC2, PC3, PC4. Through this method, the rock type can be recognized although it still have some difficulty, except the quaternary formation type. While, the techniques of visual interpretation based on photographic element and geotechnical element can strongly support to establishment of interpretation keys to lithological units (Table 2), for tectonic features (fault, fold and lineament) and also for geomorphological units.
The integrated assessment method has been used to generate a mineral prospecting zones. As a guidance, the parameters, such as condition of mineral foundation (rock type, structure, landform), geochemical mechanism of each kind of ore (especially heavy mineral), and dynamic condition for the mineral were used in both remote sensing and GIS analysis.
