ページの画像
PDF
ePub

MANGANESE

USSR Recognition of Marginal Grades

Far East

The following are some additional excerpts from the Review of Manganese Deposits of the Soviet Union, which quantify to some degree the recognition of the uneconomic grade problem.

Speaking of manganese ore shows in the Krasnoyarsk Territory, Ineiskoe deposit, Tsykin says:

"The Mn-content in the rocks, according to several
analyses, does not exceed 8-10% with an average of
3%. No oxidation zone could be traced in the
investigated areas.. The reserves of the mangani-
ferous rocks of the Ineiskoe area were estimated
at 200 million tons although their very low grade
precludes their economic exploitation."

It is obvious from the foregoing that the use of the word reserve does not have the Western entrepreneurial connotation. It is equally obvious that if the aforementioned 200 million tons are included in a reviewer's compilation, they swell the "reserve" number without adding anything meaningful.

The same author writing of the Bagzas skoe area describes Mn carbonate horizons 4.5 meters - 20 meters thick over a distance of 2.5 km. The oxidation zone is thin, reaching a depth of only 3-5 meters. Oxidized (enriched) ore contains 15% Mn and the protore has 3-5% Mn. The author's assessment is very practical:

"Despite the occurrence of large amounts of mangani-
ferous rocks (approximately 30 million tons) they
are of no practical interest because of their low
Mn-content and the presence of silicate minerals."

A considerable amount of work has been done on deposits so small as to be worthless by Western standards. Prospecting and mapping work has been done on orebodies as small as 20-50,000 tons! The grades are as low as 10-20% Mn. This same investigation attitude extends to materials of extraordinarily low Mn content. Describing a manganiferous limestone bed at the Tamalyk phosphorite deposit, Tsykin says the manganiferous limestone is 1-2 meters thick and has a Mn content of 0.5-2.5%. Similar material was also investigated at Mt. Bol'Shaya Kul'-Taiga. The author says manganiferous rocks of the Kul'-Taiga-type were the source of metal for the ore shows in the weathering zone and are also of no economic importance.

98-973 - 78 - 13

"In the enormous Krasnoyarsk Territory which has a
variety of geological structures, no Mn-ores have
yet been found which are suitable for economic
exploitation. This is not due to the fact that
they will not be discovered, but that there has
been insufficient investigation of the geological
conditions of Mn-formation."

The Irkutsk Geological Administration, in a review of manganese in the Sayan marginal trough, Tulun, Nizheudinsk, Taishet District, which is 40-100 km from rail, identifies some "deposits" as follows:

Nikolaevskoe deposit
Kettskoe
Kamenskoe

Krasnoe

6.8 million tons of 17% Mn

10 million tons averaging 12% Mn
3.5 million tons averaging 32% Mn
2.2 million tons averaging 20.3% Mn

The foregoing list is cited as typical of grade and size of seriously evaluated deposits in the USSR Far East.

"Economic Mn-carbonate deposits have not yet been
detected in the area. At the Nikolaevskoe deposit
there are interlayers of dolomite containing up to
15% Mn. All this indicates the occurrence of a
manganiferous carbonate facies and suggests the
existence of economic primary Mn-carbonate deposits."

*

Central Asia
Kazakhstan (Atasu)

The Atasu group of deposits as described by Kavun of the Kazakhstan Geological Administration is the largest Mn-ore group with "considerable reserves of economic Mn-ores." Nothing is of great economic importance in the Far East and the Atasu group in Central Asia is second in importance to the Georgian and Ukrainian deposits. On the other hand, the grades as described are not particularly impressive, viz:

[blocks in formation]

The thickness of the ore horizons ranges from tens of cm to 7-10 meters. Depth ranges from 200-1,200 meters. Extent ranges from hundreds to several thousand meters. Structure is complicated by folding, making mining complicated. Ore deposits wedge out along strike and down-dip. "The castern Karadzhal deposit was thoroughly investigated and there is no hope whatever for an increase of the reserves.

"

[blocks in formation]
[ocr errors]

A feasibility study was made by the Hydro-Mining Institute. Speaking of the Western Karadzhal deposit, the author says in talking of the low grade, "the given data show that practical exploitation of these ores is impossible without preliminary treatment.' The only favorable characteristic of the Kazakhstan ores is the moderate phospherous content ranging up to .05%. It should be noted that in the Atasu area about 70 Mn ore occurrences have been investigated, of which only 4 or 5 have any economic importance.

In northern Kazakhstan, another Mn district in the Tasobinskaya formation has been investigated and 44 occurrences averaged 24.7% Mn. The ore layers range up to one meter thick. The occurrences are hardly economic by Western standards.

USSR MANGANESE EXPLORATION EFFORTS

Since the Revolution, Soviet Union has extended a large effort to locate new manganese deposits, as shown by Figure 1 under the Reserves and Resources Section. Their success has been limited. The two largest manganese deposits, Chiatura in Georgia and Nikopol in Ukraine, were discovered in 1870 and late 1880's, respectively. Soviet geologists have been able to increase the areal extent and the total reserve of the deposits, as for example, the carbonate ores in the Nikopol deposit were found in 1939, but no major manganese elephants have been found since that time.

The last large deposit is reported to have been discovered in 1939, the Atasu group of deposits, in Central Kazakhstan and has been exploited since 1956. The crude ore reserve is estimated at 122 million metric tons with 19-30% manganese content.

Extensive geologic studies of known manganese deposits and shows in USSR by two generations of Soviet geologists, especially by A. G. Betekhtin, have identified the following major manganese ore provinces stages:

1.

2.

3.

The Ukraine-Caucasus-Urals Province of Oligocene Age

The Uralian-Kazakhstan Province of Upper Devonian to Lower
Carboniferous Age in rocks of varying degrees of metamorphism.

West Siberian Province - metamorphosed Lower Cambrian deposits Extensive efforts to locate comercial manganese deposits in the above areas and areas of similar geologic environment have been unsuccessful. It is reported that current exploration thinking is that important manganese ores may occur in the thick sequences of ancient metamorphosed sedimentary rocks. Work is being conducted to find these ores.

At the same time investigations are being conducted on different methods, e.g. heavy media, smelting, etc. to upgrade lower grade manganese ores to make then commercially usable.

The Soviet Union is aware that the decrease in the reserves of

the rich oxide ores is becoming acute in the deposits that have been exploited for a long time and, therefore, prospecting is being carried out to find new commercial deposits.

RESERVES AND RESOURCES

USSR-MANGANESE

Production and Export

The Union of Soviet Socialist Republics is considered the world's largest producer of manganese ore. The table below shows the production, export and per cent of export to production of the Soviet manganese ore for the past ten years, mainly from Nikopol deposit in Ukraine and Chiatura deposit in Georgia.

[subsumed][subsumed][subsumed][subsumed][merged small][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][merged small][merged small][merged small][subsumed][merged small]

As shown by the next table the bulk of USSR manganese ore export goes to the Eastern European countries. It is believed that Chiatura due to its higher grade provides 20% of its production for export and Nikopol 10%.

[blocks in formation]
[blocks in formation]

The USSR manganese ores and concentrates tend to be of lower. grade and are considered to have a limited market potential in the western world. In addition, USA one of the largest manganese consumers, has a statutory tariff rate of one cent per pound of contained manganese for ores from Soviet Union and Peoples Republic of China. The tariff on manganese ores from favored nations has been suspended since July 1, 1964. It is probable that if Soviet Union is granted a favored nation status, the tariff might be lifted, although the lower manganese ore grades might not be competitive in USA with other sources of supply.

The Nikopol area in Ukraine and Chiatura area in Georgia produce the bulk of Soviet manganese. The Chiatura area has the higher grade manganese ore and led Soviet production before the war. In the 1950's Nikopol developed the low grade surface deposits and constructed a number of beneficiation plants. Thus in 1965, out of total Soviet manganese production of 7.6 million tons of usable ore and concentrate, Nikopol contributed 4.7 million tons and Chiatura 2.9 million tons. Of greater significance is the increasing use of lower grade ores, as evident from the ratio of crude ore to usable ore. In 1950, 4.7 million tons of crude manganese ore yielded 3.4 million tons of concentrate. In 1965, 16.3 million tons of crude ore produced 7.6 million tons of concentrate. More current data indicates that at Nikopol to obtain 4 million tons of 45% to 48% Mn concentrate requires processing of about 10 million tons of 26% Mn crude ore and in Chiatura some 6 million tons of ore yield about 1.3 million tons of high grade and 0.7 million tons of low grade concentrate.

Reserves

Survey of available literature on manganese deposits in Soviet Union indicates that there is a lack of information pertaining to the manganese reserves in Soviet Union. Tonnages and grades for a relatively small deposit are reported in Soviet publications, whereas reserves for Nikopol and Chiatura deposits are described as "South Ukrainian Oligocene manganese bearing basin is the largest known; the deposits in the basin contain not less than 70% of the world manganese reserves." For Chiatura

« 前へ次へ »