UNIVERSITI TEKNOLOGI MARAFAKULTI KEJURUTERAAN KIMIAGEOLOGY AND DRILLING LABORATORY(CGE 558)

NAME MATRIC NOAHMAD FADHIL BIN JAHARI 2014812836 EXPERIMENT : EXPERIMENT 6 THIN SECTION AND PETROGRAPHYDATE PERFORM : 24TH MARCH 2015SEMESTER : 3PROGRAM : OIL AND GAS ENGINEERINGGROUP : EH2433NOTITLEALLOCATED MARKS %MARKS

1ABSTRACT/ SUMMARY5

2INTRODUCTION5

3AIMS/ OBJECTIVES5

4THEORY5

5APPARATUS5

6PROCEDURES10

7RESULT10

8CALCULATIONS10

9DISCUSSIONS20

10CONCLUSIONS10

11RECOMMENDATIONS5

12REFERENCES5

13APPENDICES5

TOTAL

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TABLE OF CONTENTNO.CONTENTSPAGE NUMBER

1.TABLE OF CONTENTS2

2.SUMMARY3

3.INTRODUCTION4

4.OBJECTIVES4

5.THEORY5

6.APPARATUS6

7.PROCEDURE6

8.RESULTS7

9DISCUSSIONS10

10.CONCLUSIONS10

11.RECOMMENDATION11

12.REFERENCES11

13.APPENDICES11

ABSTRACTThe fundamental objective for this experiment is to study the rocks and minerals using a microscope. Secondly, to identify the cross sections of rocks, minerals and ores. Generally, petrography is the study of rocks and minerals using a microscope. The cross sections are important for the identification of rocks, minerals and ores from this study. Thin section is served as the laboratory preparation of rock, mineral and soil being used with a polarizing petrographic microscope.

The experiment was implemented by cutting the sample rocks into a smaller samples using the cutting machine. The samples are then being polished using a piece of sandpaper to remove the bubble layers on the rocks surface. After that, rock samples were glued to the glass slide by using thermoplastic cement. The thin section lapping was set up and then the samples were placed to minimize the thickness to 30m. It were observed by using the microscope by using 4x, 10x, 20x, and 40x magnification. The characteristics of rock samples were analyzed after the observation under microscope.

On the other words, it is obviously shown that the sandstone comprising many minerals, pore spaces, matrix and cementation. Rock sample can be referred as sanstone because white colour appeared under the microscope. Also, it shows some properties of metamorphic litho logy, which is pink and brownish colour, denote to the calcite cement and likely contribute of fluid and cement. Thus, study of rocks and minerals using an integrated microscope and cross sections are important in order to determine the rocks and minerals characteristics.

INTRODUCTIONBasically, petrography is the study of rocks and minerals using a microscope. The cross sections are important for the identification of rocks, minerals and ores and to the characterization of properties such as cleavage, twining and reflectance (1). Next, thin section is defined as the laboratory preparation of rock, mineral and soil being used with a polarizing petrographic microscope. Thin sections are implemented in order to find out the properties of the minerals in the rock and at the same time to determine the origin and evolution of the parent rock.Generally, there always been two types of specimens being used for the analysis which are thin sections and polished bulk specimens. As for polished bulk specimens which are similar to metallographic specimens, the surface is prepared for examination with a refllected light microscope (1). Instead, thin sections are thin enough and typically observed by using a polarized light microscope. For this laboratory experiment, thin sections are used as for the analysis of rocks and minerals.There are general procedures necessary to prepare for making transparent thin sections at thickness of approximately 30m, and can be summarized as follow:1. Sectioning2. Vacuum impregnation3. Grinding4. Cementing to a slide5. Resectioning6. Grinding and polishing

OBJECTIVE1. To study the rocks and minerals using a microscope.2. To identify the cross sections of rocks, minerals and ores.

THEORYAs mention before, there are several steps need to be implemented for making transparent thin sections. Firstly, sectioning, a primary step in specimen preparation. It is conducted to acquire a precise size specimen from the parent material, to reduce thickness of the specimen in order to reduce grinding time and to expose the surface of interest (1). The specimen need to be cleaned and dried once it has been cut. Materials that have pores, cracks, and poorly consolidated must be vacuum impregnated. Vacuum impregnation is used to remove gases from pores or cracks in fragile specimens and allows infiltration of a suitable bonding material that will retard sample fracturing and plucking (1).Furthermore, grinding is employed to produce a flat, smooth surface which is free of gross deformation (1). This is important because it will be mounted directly to the glass slide. In cementing to a slide, it provides a transparent support to the ground sample even after it is thinned to the final thickness. The sample must be thoroughly cleaned to remove all loose abrasive and other residues before cementing. Next, as for resectioning, the part that prepare thin sections very rapidly without compromising accuracy or quality and remove excess materials quickly (1).The last part is continue with the grinding and polishing. Grinding is conducted to remove deformation in sectioning and helps removes excess material (1). It is implemented using either fixed abrasives, abrasive particles are bonded to substrate and cannot move freely, or loose abrasives, abrasive particles are not bonded substrate but are free to move. This procedure is known as lapping. Once a section is ground to the desired thickness, the specimen can be determined using transmitted light and can be further polished.The fundamental reason of polishing a specimen is to remove final deformation caused by the grinding process and produce a damage-free surface (1). It is implemented by abrading the surface with fine abrasives, reducing to sub-micrometer size. Polished thin section can be determined with either a transmitted or reflected light microscope. Instead, polishing is also important in order to identify the mineral hardness and to conduct chemical tests on the polished surface.

APPARATUS & MATERIALApparatus Rock cutting machine Thinning section lapping machine Glass slide Transmitted polarized light microscope Sectioning machineMaterial Rock samples Thermoplastic cement Sand paper

PROCEDURE1. Different sample of rocks were prepared which are Sample 1 and 2. Sample 1 was cut with the thickness of 3mm by using rock cutting machine.2. Power supply and light of the machine were switched on. Hood was opened. Sample was clamped in the clamping device.3. Path of the flange was checked before cutting. If the black knob and the screw pin could touch the flange, re-position the vise assembly. After that, hood was closed.4. Pump was turned on. Then, start button was pressed.5. Cut-off wheel was taken slowly towards the sample. Stop button was pressed and then the hood was opened. Sample was collected and the ward from the cutting area was cleaned.6. Pump and the light were turned off. The power supply was switched off simultaneously.7. Sample was polished by using sandpaper and was put on a glass slide by using thermoplastic cement in the fume hood.8. Rock sample was thinned for 30 m by using thin section lapping machine and was polished again using the sandpaper.9. Sample was observed with a transmitted polarized light microscope for 4x, 10x, 20x and 40x magnification to determine type of rocks, minerals and ores. Data were recorded.10. Step 2-9 were repeated for sample 2.RESULTRock Sample 1

Magnified 4X

Magnified 10X

Magnified 20X

Magnified 40X

Rock Sample 2

Magnified 4X

Magnified 10X

Magnified 20X

Magnified 40X

DISCUSSIONAs mention before, the main objective for this experiment is to study the rocks and minerals using a microscope. Cross sections are important in order to identify the rocks, minerals and ores. The sample is identified by using polirizing microscope with for types of magnification which are 4x, 10x, 20x and 40x. The magnification is further used to identify more precise on determining different type of rocks. Based from the results obtained, denote that the rock samples comprise many types of components correlate to the characterisitic of sandstone. It shown that the grains is comprising of many types of minerals, pores spaces, matrix and cementation. The colour of the rock samples is white which refer as sandstone. Furthermore, there is limitation occur from the experiment. Results obtained are not precise and seems unclear during magnification implementation. It is necesssarily will influence the results because the structure of the rock samples cannot be seen clearly, instead, some of the results may vary from the exact one.As the magnification increase from 4x to 10x, 20x and 40x, the images seem to be seen more clearly than before. Based on the result from Sample 1 and 2 it clearly shown that the pore spaces are exists within the rock samples while the grains, matrices and cements still in vague. At 20x magnification, both samples show some properties of metamorphic litho logy, which is pink and brownish colour appeared indicate to the calcite cement, and somehow the samples contribute of fluid and cement.

CONCLUSIONAs overall, the objective for this experiment is finally achieved. Study of rocks and minerals using an integrated microscope and cross sections are important in order to determine the rocks and minerals characteristics. Instead, several properties likely, their colour, shape, hardness, cleavage and others can be determine simultaneously. It is crucially necessary to know mineral characteristic, it helps for the determination of the rock permeability and porosity to be done precisely. Thus, it is clearly shown that the sandstone comprising many minerals, pore spaces, matrix and cementation. Somehow, limitation always occur and the results may vary and not precise during observation.

RECOMMENDATION In order to prevent the formation of bubbles, the rock samples need to be polished few times by using the sand paper. Due to some limitation error, the thickness of the samples shoul be decreased to ease the penetration of light from the microscope to the samples. Samples need to be hold and clamped firmly during cutting to avoid any unexpected movements of samples.

REFERENCES(1) Buehler Digest (1987). Petrographic Sample Preparation For Microstructural Analysis, Vol. 24, No. 1

APPENDICES

Geological Cutter

Thin Sectioning Equipment

Transmitted Polarized Light Microscope & Computer

Interference Colour Chart

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