General Information

Chin state is located in the north - western part of Burma forming the boundary between India, Bangladesh and Burma. It is divided into 9 townships viz. Tiddim,Tonzang, Hakha, Falam and Thantlang in the northen part of Chin State and Matupi, Mindat, Kanpetlet and Paletwa in the sourthern part of Chin State. The total area of the Chin State is 13907 sq milies. It is mostly inhabited by the Chins. According to 1981 Consus, the total population is over four Lakhs. The State Capital is Haka. Siallum Fort of Chin State is one of the most famous indigineous forts recorded in the Burmese history. The Chin peoples fiercely resisted the British imperialist Army for 3 years. Sergeon Dr. Le Quesne won the highest British Gallantry Medal, Vicoria Cross in the Siallum battle field against the brave Chins.

Previous Conception on the Geology of Chin State

There has not been any previous geological mapping in the Chin State before the 2nd world war, because the region is highly rugged, too remote, difficult of access and never appeared to be attractive for mineral deposits. Whatever information obtained about the geology and mineral deposit of the Chin State in the past, in general, is mostly conjectural and extrapolated. The only type of rocks recorded in the Chin State is mainly Chin shale - Axials of Triassic age and Kanpetlet schist. The mineral occurrences recorded in the past are only a few pyrites and slates. The previous workers neglected and overlooded the most important mineral - bearing rock such as ultrabasic rocks exposed over an extensive areas in the tectonic zones along the eastern foothills of the Chin State.

Previous Geological Works

In 1871 and 1873, the first accounts of geological works in the Indo - Burman Ranges were made by Theobald and Noetling (1895) from Geological Survey of India.

In 1960-61 a geological party from M.D.C headed by U Ngaw Cin Pau, after selecting favourable areas for finding minerals from the air photos, conducted a geological and mineral prospecting survey in Kale-Falam area. Saw, Kanpetlet Mt. Victoria and the tectonic zones along the eastern foot - hills of the Chin State from webula through Mwetaung to India - Burma border.

As the result of this survey, rich deposits of nickel and chromite associated with ultrabasic rocks was discovered in Mwetaung hill.

In 1977-79, a geological team from Geological Survey and Mineral Exploration Project (DGSE) under UNDP programme conducted geological mapping in parts of Tiddim, Tonzang, Falam, Haka and Mindat townships of the Chin State. Geologically, about 70 percent of the Chin State still remains unsurveyed.

Geology of the Chin State

On the basis of the geological date compiled from the geological mapping so far completed, the Chin State is found to be made up of 8 different rock types as shown below:

Sedimentary:

(1) Irrawaddian type of rocks

(2) Peguan type of rocks

(3) Kennedy Sandstone

(4) Chunsung Mudstone Turbidite

(5) Falam Mudstone Micrite

(6) Pane Chaung Group

Metamorphic:

(7) Kanpetlet schist and khwekha metamorphic

Lgneous:

(8) Ultra - basic rock (Nickel and Chromite bearing rock)

Mineral Deposit:

The mineral prospecting survey was conducted in the field with the help of photogeological maps prepared before field work. The most promising area and geological structures favourable for mineral deposits are studied first from the aerial photographs and located in the photogeological map. A follow-up prospecting survey was conducted in the field. Since Burma got Independence, many new mineral deposits such as commercial deposits of Nickel, Chromite, Steatite, limestone of commercial deposits, peridotite deposit for decorative marble, and slate deposits are found in many parts of the Chin State.

Nickel Deposit

Nickel deposits associated with Ultra basic rocks were found in Mwetaung, Mualvailup, Bokpivum in Tiddim township, Webula and Khwekha in Falam township and Maungdaw hill in Kanpetlet township of Chin State. Out of these, Mwetaung Nickel deposits are of commercial interest. In other areas, the size and the grade of the deposits are small and low and are of no economic significance.

Chromite Deposit

Chromite deposit associated with ultrabasic rocks were also found in Webula, Bokpi -Vum and Mualvailup hills in the Eastern Chin State and Maungdaw hill in Kanpetlet area. The possible are reserves estimated from these deposits are over 12000 tons.

Limestone Deposit

Limestone deposits of commercial quantities are found at Pahataung near Mwetaung hill, Hausapi-taung near Sialthaw village, Lamzang and Lophei villages of Tiddim township and at Phaitu village of Tonzang township. The potential are reserve estimate is over eighty million tons. More reserves are expected if detailed investigation is conducted. A further detailed investigation should be conducted to evaluate the grade and the potentiality of the deposits as to weather they could be used for cement industry and decorative marble.

A huge deposits of highly fossiliferous limestone are also found at Lungpi (or) Lungrang hill and Lailun hill, accessible by car from the nearby Falam town and also not far from Ngalsip Hydro-electric plant in the Chin State. The potential reserve of these deposits estimated during the preliminary investigation, is over 100 million tons. Chemical assay shows that they can be used for cement and limeburning industry. (Caco396.5 percent, Cao 53.5percent, Mgo 0.8 percent, Sio2 1.6percent)

Slate Deposit

Two types of slates are found in the Chin State. The Chocolate colored slate of good quality are found near Gamngai and Salzang villages of Tiddim Township. This slate belt is striking North-South direction extending for a distance of 16miles from Gamngai to Gelmual village. Many thousand ton of these slates have been extracted for roofing Pyithu Hluttaw Building in Rangoon. The dark-colour slates of good quality are found near Limkhai, Dak Bung and many places in the Chin State. They are mostly used for cshool slates, roofing houses and memorial stones.

Steatite Deposit

Steatite deposits are known to occur in three localities in the Chin State viz. at Laisuang Chaung near Dolluang village, at Nattaga Chaung near Mwetaung hill and Mawnglang village of Tiddim township and at 6 mile Sakha, 2 miles east of Kanpetlet town. The potential reserve estimated from Kanpetlet is 9,000 tons. No exploration to evaluate the grade and potential reserve has been done from the first two localities. They are used for the manufacture of soap and talcum powder.

Decorative Stone

The peridotite rocks are abundantly found in Webula Bokpivum and Mwetaung hill of Chin State. Samples are taken to Rangoon and cut into 4 sided slabs. On polishing, it is found that they can be used as decorative marbles giving an attractive dark-green color. In Japan and many countries of the World many million tons of these dark-green peridotite marbles are imported and widely used as tomb-stone, decorative walling and flooring of both Government and private buildings.

Pyrite Deposit

Pyrite crystals dissemminated in the limestone and dard slates are found in many places, but no deposit of commercial quantity is known so far.

Ochre Deposit

The Kanpetlet schists are found to contain a bright yellow ochres used for pigment industry. Almost all springs from Kanpetlet schists produce such ochreous material containing 38% of iron, but no deposit of commercial significance is known so far.

Conclusion Remarks

While building up a Socialist Economy in the country, the first and foremost important thing to do is to conduct a detailed natural resources survey to know the grade and the potentiality of our mineral wealth, industrial Raw Materials, forest products, soil and agricultural products and natural hydro-electric power potentials in the country. Only when we know our natural wealth and natural power petentials we shall be able to draw various development plans.