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INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES

Volume 2, No 3, 2012

© Copyright 2010 All rights reserved Integrated Publishing services

Research article ISSN 0976 – 4380

Submitted on December 2011 published on February 2012 842

Application of Remote Sensing for delineation of Uranium bearing

Vempalli dolomites in and around Tummalapalli area, Cuddapah Basin,

India Raghu Babu. K, Sudarsana Raju. G

Department of Geology & Geoinformatics, Yogi Vemana University, Kadapa, A.P.India

[email protected]

ABSTRACT

The Uanium mineralization within the Vempalli dolomites of Cuddapah Super group in

Mabbuchintalapalli, , Tummalapalli area falling in the Survey of India Toposheet No. 57 J/7.

The Remote Sensing data obtained from IRS P6 LISS III imagery of both the areas is taken

as reference for the Interpretation studies. The Remote Sensing data obtained from IRS P6

LISS III imagery of both the areas is taken as reference for the Interpretation studies. The

associations of alteration processes throughout and near the mineralized sectors appear to

play an important role in the distribution and localization of the mineralization. The aim of

this study was to assess the effectiveness of LISS III data for detecting alteration zones as

well as Uranium mineralization in parts of Cuddapah basin.

Image processing techniques were applied on the digital subset LISS III data covered studied

areas. These techniques generated several products of enhanced satellite imagery such as

ratio images, principal component analysis and edge enhancement techniques which have

been successfully used in the lithological discrimination of alteration zones and uranium

bearing dolomites, structure, geomorphology, alteration zones etc., of the study area.

Extensive field geologic studies in the pronounced zones delineated by the image lead to the

identification of mineralized locations.

Key words: Localization, Cudddapah Basin, Alteration zones, Uranium

1. Introduction

Digital image processing, onscreen interpretation and GIS, applied to the IRS P6 LISS III

imagery of Tummalapalli areas of Cuddapah basin for mineral mapping. False colour

composite, principal component, band ratio, edge enhancement, highlighted areas of

hydrothermal alteration were successfully applied and results integrated with available

previous data. The interpretation is not restricted to identifying object on the image but, it

also usually includes determination of their relative locations and extents. A systematic study

of satellite images usually involves a consideration of two basic elements, namely image

elements and terrain elements. Image interpretation of terrain elements and image elements

with identification of geological features based on variations in spectral signatures help in

satellite based geological mapping. Altered rocks were recognized by their appearance in the

visible spectral bands in remote sensing (Subhash babu et al., 2009). Most mineral deposits

are accompanied by hydrothermal alteration of country rocks. The ability to discriminate

between hydrothermally altered and unaltered geologic materials is of considerable practical

value, particularly in mineral exploration and assessment studies. Reflection spectra of

particular mineral that commonly occur in hydrothermally altered rocks and soils were

recorded to display their features at their natural spectral bandwidths in the near-infra red

Application of Remote Sensing for delineation of Uranium bearing Vempalli dolomites in and around

Tummalapalli area, Cuddapah Basin, India

Raghu babu. K, Sudarsana Raju. G

International Journal of Geomatics and Geosciences

Volume 2 Issue 3, 2012 843

from 1.3 to 2.4µm (Hunt, 1979). In addition to information available in the range 0.4 to

1.1 µm, very useful information exists through the near-infrared range from 1.1 to 2.5 µm,

due to the vibrational processes occurring in some of the molecular groups that constitute

minerals and rocks (Hunt, 1979).

2. Study area

The Study area, Mabbuchintalapalli and Tummalapalli are situated in the southern margin of

the Cuddapah basin over the Vempalli formation underlain by Gulcheru quartzies and

Penunsular Gneissic Complex in the Survey of India toposheet No. 57 J/7 between longitudes

78015`00``, 78

020`00`` and latitudes 14

015`00``, 14

020`00``/14

025`00``covering an area about

1200 Sq.km (Figure 1).

Figure 1: Location & Geology

3. Methodology

The approach involves database preparation, digital classification and systematic on-the-

screen visual interpretation of space borne multispectral digital data. A flowchart portraying

the methodology adopted in the present study is appended as (Figure 2) is given hereunder.






Figure 2: Flow chart showing the methodology

3.1 Preparation of Database

Preparation of database involves geo-referencing and fusion of multi-spectral and

panchromatic digital data. Details of various steps involved are as follows.

3.2 Geo-referencing

The IRS P6 LISS III data were digitally co-registered to Survey of India toposheet 57J/7 and

57 J/13 at 1:50,000 scale using ERDAS/IMAGIN software.

3.3 Preliminary Digital Analysis

For objective assessment of the sediment detachment, information on the land cover, slope,

management practices, soil erodibility is essential. Hence preliminary interpretation of

satellite digital data was carried out to delineate various landform categories in co-junction

with the Survey of India (SOI) toposheet. Simultaneously, preliminary interpretation was

also done for mapping soil properties exploiting the inherent relationship between lithology,

physiography and land cover.

3.4 Ground Truth Collection

Ground truth mission was subsequently planned to establish the relationship between image

elements, namely colour, texture, shape, size, shadow, pattern, association, etc, and various

features identified during preliminary digital analysis.






3.5 Final Digital Analysis

Different interpretation techniques for inferring various features were applied to the IRS P6

LISS III satellite imagery of study areas by using ERDAS/IMAGIN and GIS software.

1. Subsetting: the study area present study has been separated from the imagery by the

technique of subsetting (Figure 3).

2. Edge enhancement techniques: both high pass and low pass filtering techniques were

applied for delineating the fracture zones, fault zones, linear features which are

probable mineralized zones (Figure 4).

3. PC analysis: water bodies and land patterns are distinct in PC analysis than the False

Colour Composite. Lithological and alteration zones discrimination is more

significant in PC in contrast to the FCC (Figure 5).

4. Band ratio technique: this technique is adopted to get the reflectance properties of

alteration minerals and uranium mineralization in the present study area (Figure 6).

5. Texture: Textural classification studies are useful for the study of frequency of tonal

changes in an image. Texture is produced by an aggregate of unit feature which is

product of individual shape, size, pattern, shadow and tone (Figure 7).

6. The reflectance curves of Pyrite and Chalcopyrite drawn between wavelength and

reflectance in the image. The graphs showing peaks for pyrite at 0.3 µm to 2.5 µm

where as for chalcopyrite at 0.5 µm to 3.0 µm (Figure 8).

Figure 3: Subset image of Tummalapalli area 57 j 07






Figure 4: 7x7 Highpass Filtering

Figure 5: 5 PCA of Tummalapalli area 57J07






Figure 6: IR/R of Tummalapalli area 57J07

Figure 7: Texture






Figure 8: Reflectance values of Pyrite and Chalcopyrite

3.6 Geology

For investigating the lithology of the study area, the IRS P6 LISS III imagery has been

geometrically corrected and represented in everest projection using the Survey of India

Toposheet Nos. 57 J/7 and 57 J/13 on the scale of 1:50,000. Then the imageries have been

exported to Geographical Information System for delineating lithology for the preparation of

geological map (Figure 3). The geological succession of the study areas is as follows.

Table 2: Geological succession of the study area

Nandyal shale KURNOOL GROUP

Koilakuntla limestone

----------- Unconformity ----------

Cumbum formation NALLAMALAI GROUP

Bairenkonda quartzite

-------------- Unconformity------------

Gandikota quartzite

Tadipatri shale CHITRAVATHI GROUP

Pulivendla quartzite

----------------- Disconformity ------------

Vempalli formation

CUDDAPAH

SUPER GROUP

PAPAGNI GROUP

Gulcheru quartzite

(After Nagaraja Rao et al 1981)






5. Interpretations in Mabbuchintalapalli, Tummalapalli area

5.1 Geology

The geological formations in Mabbuchintalapalli, Tummalapalli area composed of Peninsular

Gneissic Complex overlain by cyclic sequence of conglomerate quartzite and shale. The

sequence is as follows.

1. Cherty Dolomite

2. Limestone

3. Quartzite

4. Peninsular Gneissic Complex

5.1.1 Peninsular Gneissic Complex

The Cuddapah Supergroup comprising cyclic sequences of conglomerate-quartzite-shale with

minor carbonates (stromatolytic dolomites) and basic volcanic and intrusive was deposited

over denuded and upturned edges of the Archaean gneisses, granites and supracrustals known

as Peninsular Gneissic Complex.

These rocks show dark tone in the VNIR range (Yousif, M.S.M., and Shedid, G.A.,1999).

Alteration products comprise clays which possess absorption bands in the SWIR region (2.1-

2.4 µm). Silicate absorption bands occur in the TIR region (10-11.5 µm).

5.1.2 Quartzite

They show light to dark tone, coarse texture, coarse drainage and very sparse vegitation in the

imagery. Extensively developed talus is observed in the imagery on the slopes of hills

composed of these rocks. This litho unit belongs to Gulcheru quartzite and Pulvendla

quartzite, with wide spread joints and structurally controlled drainage pattern. Sparse to

scrub vegetation is observed.

5.1.3 Shale

Shales show medium to dark tone, fine to medium texture, fine textural drainage, closely

spaced bedding gives some linear pattern in the digital imagery. This litho unit observed in

the study area at to two stratigraphic horizons over the Nallamalai group and asigned

as,Nandyal shale formation of the Kurnool group and the other occurring as intercalation with

the phyllite rock unit belongs to the Cumbum/Pullsmpet formation of the Nallamalai Group

forms as a valley and ridge forms indicating differential erosion of the litho units.

5.1.4 Limestone

Limestone show grey tone, medium and mottled texture, have less surface drainage, with sink

holes, dolines, solution channels etc., sometimes show contorted bedding. Limestone

exposed in the study area represents both Nallamalai group and Kurnool group. Limestone

patches occurring as small patches in N-E part of the study area belongs to the Cumbum

Formation of Nallamalai group where as that occurring in the western part of the study area

belongs to the Koilakuntla formation of the Kurnool group.






5.1.5 Dolomite

This litho unit belonging to the Cumbum Formation of the Nallamalai group is exposed at the

North-North eastern part of the study area forming a small dome like structures.

5.2 Structures

Space imageries and space photographs cover large areas. Hence structures of regional level

are easily descernible on these. Different structural elements interpreted in the structural map

(Figure 5) through the digital imagery in the study are as follows

5.2.1 Horizontal planar structures

They show tonal banding representing lithological banding and bedding, contoured

appearance of tonal banding on low dipping beds and tonal banding accentuated by

vegetational banding.

5.2.2 Linear structures

In the digital imagery joint, fault or unconformity can be marked as linear traces.

Unclassified linear features are referred to as lineaments. They can be recognized by

i. Joints: Joints are expressed as lineaments, rectangular, parallel or linear drainage pattern,

linear vegetation pattern or short criss cross linear patterns. Joints are well expressed in

quartzites in the study area than other rock units. There are two sets of joints are present

viz., bedding joints and transverse joints.

ii. Faults: In the digital imagery most of the faults are expressed as straight or gently curved

lines known as photolineaments, linear depression and linear scarps, alignment of

vegetation, straight segments of streams and waterfalls across streams, alignment of

ponds and springs, normally vegetation on two sides shall be different when the

lithologies are different. Drainage pattern on two sides of the fault shall be different,

change in land form on either side of the lineament, lithological change shall also be

reflected by tonal change and offset of ridges, beds or structures.

5.2.3 Folds

Fold structures can be interpreted from orientation of dipping planes, land form, drainage,

shape and pattern. Change in pattern of dips is also indicative of folded nature of the terrain.

Change in dips is also indicative of folds.

5.2.4 Mineralization

The basal Gulcheru conglomerates at the base of the Cuddapah basin were found to be

thoriferous. The uranium mineralization is hosted by impure phosphatic dolostones of

Vempalli Formation of Papaghni Group. It extends from Chelumpalli in the northwest to

Maddimadugu in the northeast over a belt of 160 km with promising mineralization at

Tummalapalle, Rachakuntapalli and Gadankipalli in the central part.

5.3 Significant Interpretations from Digital imagery






The selected image subset is prepared as shown in Figure supervised and unsupervised

classifications were applied to study different rock unit in the study area. Various rock units

have been delineated by studying the nature of fracture, faulting, texture of the rocks,

drainage patterns and various thematic maps have been prepared for identification of uranium

baring dolostones of Vampalli Formation.

5.4 Alteration minerals

The study area in the image showing spectral signatures significant for the minerals like

pyrite, chalcopyrite. The reflectance curves of Pyrite and Chalcopyrite drawn between

wavelength and reflectance in the image. The graphs showing peaks for pyrite at 0.3 µm to

2.5 µm where as for chalcopyrite at 0.5 µm to 3.0 µm (Figure 8).

5.5 Uranium mineralization

The granitic rocks are considered as one for the most important source for uranium deposits

(Shalaby, M.H., et al 2009). The present work concerns with Mabbuchintalapalli, and

Tummalapalli areas, where the basement is granitic followed by Gulcheru quartzites,

Vempalli limestones and dolomites. Image processing techniques were applied in this work

to define main characteristics features of the dolomite rock bearing uranium mineralizations.

The IRS LISS III image was used to recognize and map the investigated areas. The colour

composite images and application of principal component analysis of LISS III data lead to

identify and characterize the uranium bearing dolomite in the investigated areas.

5.6 Conclusions

Remote Sensing is largely used for mineral exploration (Rowan and Bowers 1995; Abdel-

hamid and Rabba 1994; Kaufmann, 1988; Abrams, 1984; Rowan and Kahle, 1982),

especially for (i) mapping regional lineaments, (ii) mapping local fracture pattern that may

control individual ore deposits (iii) detecting hydro-thermally altered rocks associated with

ore deposits and (iv) providing basic geologic data. Various digital image processing

procedures were applied such as ratioing, PC analysis. In the present an IRS P6 LISS III

satellite image covering an area of approximately 720 sq. km pertaining to the Survey Of

India toposheet no. 57 observed 57j/14 between longitudes of 78045` and 79

000`, latitudes of

14030 and 14

045` was digitally processed and interpreted to elucidate the lithology, structure

and geomorphology of the study area. Geological elucidation consists of tonal demarcation

of the various geological members of the region mainly Quartzite, Limestone, Dolomite,

Shale/phyllite. Observed linear features were classified into various categories viz., faults,

fractures/joints, lineaments. Delineation of these rock units is illustrated by texture analysis

of the image using ERDAS Imagine software. The Principal Component Analysis (PCA)

enumerates the alteration minerals around the mineralized zone and they are more enunciated

by the Band Rationing technique. In the present study the filtering techniques adopted to

delineate the fractures and fault zones. These studies are more useful in narrowing down the

mineralized zone.

6. References

1. Abdelhamid, G., and Rabba, I., (1994), An investigation of mineralized zones

revealed during geological mapping, Jabal Hamra Faddan-Wadi Araba, Jordan, using

Landsat TM data, International Journal of Remote Sensing, 15, pp 1495-1506.






2. Abrams, M.J., (1984), LandSat 4, Thematic Mapper and Thematic Mapper Simulator

data for a Porphyry Copper Deposit, Photogrammetric Engineering and Remote

Sensing, 50, pp 1171-1173.

3. Hunt, G.R., (1979), Near Infrared (1.3-2.4µm) Spectra of altered minerals potential

for use in Remote Sensing, Geophysics, 44, pp 1984-1986

4. Kaufmann, H., (1988), Mineral exploration along the Aqaba-Levant structure by use

of TM data; concepts, processing, and results, International Journal of Remote

Sensing, 9, pp 1639-1658.

5. Nagaraja Rao, B.K., and Ramalingaswamy, G., (1976), Some new thoughts on the

Stratigraphy of Cuddapah Supergroup Seminar on Kaladgi-Badami, Bhima and

Cuddapah Supergroup, Mysore, pp 17-20 abstracts.

6. Rowan, L.C. and Bowers, T.L., (1995), Analysis of linear features mapped in

Landsat Thematic Mapper and side-looking airborne radar images of the Reno,

Nevada 1° by 2° quadrangle, Nevada and California-implications for mineral resource

studies, Photogrammetric Engineering and Remote Sensing, 61, pp 749-759.

7. Rowan, L.C., and Kahle, A.B., (1982), Evaluations of 0.46-2.36 micrometer. Multi-

spectral scanners images of the East Tintic mining district, Utah, for mapping hydro-

thermally altered rocks, Economic Geology, 77, pp 441-452.

8. Shalaby, M.H., Bista, A.Z., Roz, M.E. and El Zalaky M.A., (2009), Integration of

Geologic and Remote Sensing Studies for the discovery of Uranium Mineralization in

Some Granite Plutons, Eastern Desert, Egypt Journal of Earth Science, 1, pp 1-25.

9. Subhash Babu, Raushan Kumar and Siva Subramanyam K.A., (2009), Identification

of Hydrothermal altered zones for Mineral exporation, Vector1media.com

10. Yousif, M.S.M., and Shedid, G.A., (1999), Remote sensing signature of some selected

basement rock units from the central eastern desert of Egypt, Egypt journal of Remote

Sensing & space Science, 1, pp 132-141.

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