The Hanaoka-Mine is one of the typical black ore deposits and belongs to the so-called green tuff region of the Miocene, Tertiary.
The ore deposits consist chiefly of five kind of ores, that is, black ore (Sphalerite-galena-barite), yellow ore (Chalcopyrite-Pyrite), sulfide ore (Pyrite) and gypsum ore (Gypsum). There are some large scale gypsum ore deposits in the Haneoka-Mine.
The writer reports the some different occurrences of the three gypsum ore deposits, which are Bandai, Tutumi-zawa and Oishi-zawa gypsum ore deposit, from other metallic ore deposits in Hanaoka-Mine.
Generally speaking, thier occurrences, are follows. The large scale gypum ore deposits in Hanaoka-Mine
(1) have the N-S arrangement west of the Doyasiki deposit
(2) have up-lifted dome shaps
(3) don't accompany the white-coloured-rhyolite lava, as other metallic ore deposits in Hanaoka-Mine, in their lower horizon
(4) don't accompany relatively so amount of metallic ore on their uppermost
(5) have chlorite clay whenever they contain clay in them

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The Hanawa Mine belongs to the ore deposits of so-called "Black ore", but it is not so typical in the assemblages of ore minerals. It consists of chalcopyrite-pyrite-gypsum for the most part and sphalerite-barite in some parts. The Hanawa mining district belongs to "Green Tuff" region of the Miocene, Tertiary, and Senosawa formation, containing the ore deposits is composed pyroclastic rocks. All ore deposits in massive, lenticular or bedded form seems to be occurring in almost the same horizon of the formation. In addition to the introduction of the geology and ore deposits, some problems of the prospecting are reported in this paper.

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The Ainai mine has been operated again after the second world war by finding of black ore deposits. It is located in the northern part of Kazuno basin in Akita Pref., about 6.5km north-west from the Kosaka mine.
The older rocks of this mine are rhyolite, altered volcanic rocks and pyroclastic rocks belonging to the miocene epoch in the Tertiary. These rocks are immediately overlaid or intruded by alteredbasalt. In the western part of this mine, this basalt is overlaid still by the alternations of blackshale, tuff and lava, and they are intruded by dacite and rhyolite.
After their activities, dolerite is penetrated into these rocks by volcanic activity and it is found in all parts of this area.
There are six ore bodies in this mine, and four of them are typical black ore bodies. These ore bodies occur mainly in rhyolite, altered volcanic rocks and pyroclastic rocks. But in exception, they replace altered basalt or dolerite.
The form of them are bedded ellipsoid.
The prospecting affairs are generally drilling, ore sampling, and calculating of grade and tonnage of ore. Besides them, preservation of mine and co-operation with ore-dressing are practiced.

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The Hosokura mine is one of the largest zinc and lead mines in Japan and is located in the Miyagi prefecture.
The mine area is composed of propylite, rhyolitic rocks, dacite, green tuff and dacitic tuff which belong to the Tertiary period.
Most of the veins occur in the propylite and rhyolitic rocks and some occur in the green tuff, and these veins were, formed as an epithermal fissure-filling deposit in the Miocene epoch.
Writers apply the idea of the "Strain Ellipse" to the original fractures in Hosokura, and classify them into the the tension fractures and the shear fractures. The tension fractures which are comparatively simple and stable are prevalent in the central part of the propylite, and shear fractures which are more complicated and unstable than the former are prevalent along the marginal parts of the propylite.
It is considered that these fractures were controlled by the intruded igneous bodies and were formed by the compressive stress.

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The Ashio Mine is composed mainly of the rhyolitic comlex and the Palaeozoic formation. The ore deposits occur both in them as vein and "Kajika" deposits.
Four hypogene mineral zones, a central Sn-W-Bi-Cu zone, an intermediate Cu-As-Zn zone, a marginal Zn-Pb-Cu-As zone and a barren zone are quite distinguished in the rhyolitic complex as Takeshi NAKAMURA (1961) clarified them.
Hypogene mineralization in the Palaeozoic formation and in the southern part of the rhyolitic complex adjacent to the Palaeozoic formation is very similar to that in the rhyolitic complex, but large amounts of ealier pyrrhotite and marmatite occur in the Palaeozoic formation. In general, three mineral zones, a Fe-Zn-As zone, a Cu zone and a silicified and barren zone are distinguished remarkably from the foot-wall side to the hanging-wall side of the "Kajika" deposits in the Palaeozoics.
The mineralizations both in the rhyolitic complex and the Palaeozoics are considered to be taken place at the same time after the rhyolitic complex extruded.
The features of the high-temperature tin and tungsten minerals are associated with the low-temperature copper, lead, zinc and other minerals show the telescoped character of the Ashio deposits. The ore deposits at the Ashio Mine classified as the epithermal deposit are considered to be formed under the subvolcanic environment caused by the vocanism of the Ashio rhyolitic complex.

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The ore deposits of Akenobe Mine is subvolcanic hydrothermal copper-lead-zinc-tin-tungsten quartz vein. The ores consist mainly of chalcopyrite, sphalerite, cassiterite, galena, bornite, wolframite, scheelite, arsenopyrite, magnetite, and subordinate amount of pyrrhotite, pyrite, bismuthinite, native bismuth, molybdenite, etc. The ores are associated with quartz, chalcedonic quartz, fluorite, calcite, siderite, chlorite, apatite, manganiferous calcite, and clay. minerals.
The geology of this district is composed of mainly Paleozoic sedimentary formations, gabbroic intrusive rocks, granophyric rock and many kinds of dike rocks.
For the purpose of zonal distribution investigation. the writer was availed to great number of chemical analyses of ores and geologic data. From the results of observations based on these data, understood remarkable arrangement of ores within vein groups, are as follow :
(1) The zoning at Akenobe is showing on both horizontal and vertical.
(2) Five zones are recognized, SnW-CuSn-CuZn-PbZn-AuAg, which are consist of from central to peripheral zone.
(3) The zonal arrangement is controlled by many factors, such as pre-ore NE faults, interstructure of vein flssures, erosion of surface, post-ore movement, difference in country rocks, and repeating of mineralizations, gradient of temperature and pressure, etc.
(4) The most important factor in the localization of zoning is pre-ore NE faults. Those are lie along the gabbroic intrusions.
The writer conculudes that main paths of mineralizing solutions are the NE pre-ore fanlts and mineralized solution had ascend through its faults. Therefore characteristic zonal distribution was formed.
These geological features are important in prosecting.

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Recent developement of the mine and geological studies had disclosed the Mo, Cu Zn and ZnPbzone in pyrometasomatic lead and zinc deposits. Existence of cryptobatholith is presumed in the Mo-zone from the occurence of acidic igneous intrusives, which is considered as a source of mineralizing solutioa.
Decrepitation temperatures of hedenbergite and ratio of Ag. Pb. Zn (main ore of the mine) show several local centers of mineralization and the direction of flow of mieralizing solution, which suggest the extention and chnge of ore bodies.

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Kamashi Mine liegt in Kitakami-Gebirge, Nördostliches Honsyü, Japan. Heute ist diese Mine unterem Betriebe der Nittestsu. AG. Diese Mine liegt in der Grenze zwischen südlichem Kitakami Gebirge und nördlichem Kitakami Gebirge. Die Paläozoikum Gestein (Devon, Karbon, Perm.), Mesozoikurn Gestein (Jura.) und die vulkanischen Gebilde verbreiten sich weit. Die geologischen Strukuturen können in fünf Teile vom West zum Ost teilen. Es ist wie folgt.
(1) Tono-ofunato tektonische zone
(2) Rokkoshi-Ashigase tektonische Zone
(3) Sasayama-Aizen tektonische Zone
(4) Hayachine-Goyozan tektonische Zone
(5) Hayachine-Kogawa tektomische Zone
Diese tektonische Zonen werden von der Grundstruktur gekontrollt. Die Dislokation von Kamaishi Mine sind N-S und E-W Richtung und jener wird von der Richtung der Grundstrukturen gekontrollt, dieser von der Bodenerhebung und Einfluss der vulkanischen Gebilde. Nach den mächtigen Falten entstehen die treppelichen Falten, die Dislokation des Fächer-Bildes und die Blöckebewegungen. Die Erzlagerstätten von Kamaishi Mine werden von der Strukturen des Grundgestein gekontrollt, dass sie tektonische Zonen in Kitakami-Gebirge sind.

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The ore deposits of Kishu Mine consist of several veins running pararell with each other at intervals of some two or three hundred meters. These veins do not penetrate so deep that range of working areas become inevitably wider. Accordlngly, in order to obtain possible deposits it is naturally important to draw and study the topographical and underground maps.
The works of exploration corps are aimed at two directions, i. e. topographical surface measurement and underground survey. In the case of the former, we draw both 1/5000 and 1/2000 topographical measurement sheet, and 1/10000 photographic birds eye views has also become available for our purposes. In the case of the latter, we draw five kind of survey sheets presently. But to rationalize the exploration works, we intend to reduce these to two kinds in the near future, 1/2000 and 1/500 measurement sheets. Original sheets of our survey results are of sheet system.

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Siuce 1951 the rotary diamond boring works have been done at the Abuta Iron Pyrite and Sulpher Mine, Hokkaido, Japan and three drillingworks have been performed up to date for the special purposes of :
(1) Drilling hole to penetrate the strong acid water which streams from main level tunnel.
(2) Large diameter (7") drilling to take samples for smelting.
(3) Liquidity test of underground water around the deposit by using drilling hole.
On this report we wish to refer to the actual acievement and others of the prospecting drilling and the drilling for the liquidity test of under ground water.

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The Toyoha mine is located about 25 kilometers northwest of Sapporo Hokkaido
The rocks in the vicinity of the mine consist of Toyoha formation of the Miocene. sediments such as tuffaceous sandstone, shale and conglomerate. They are covered by propylite and intruded by acidic and basic dykes. All rocks mentioned above are covered by Quaternary andesitic lava.
The ore deposits occur as epithermal fissure filling veins in the shear zone having EW trend and in the NW-SE trending tension fracture.
These fractures might have been formed by the tectonic movement in late Tertiary related to the intrusion of acidic dykes along the synclinal axis having EW trend in Toyoha formation. Mineral assembrage are classified by the order of mineralization as follows:
1. Silver bearing Galena-Sphalerite-pyrite of 1 st stage mineralization in the shear zone having EW trend.
2. Chalcopyrite-pyrite of 2 nd mineralization in the tension fracture having NW-SE trend.
3. Rhodochrasite-calcite-silver bearing quartz of latest mineralization in the both fractures.

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The zinc deposits of Pa-daeng area consist of Main Ore Body sitting astride the mountain ridge like a saddle, 12 kilometers east-southeast of Maesod town and other minor outcrops scattered northwestward to an extent of 2, 700 meters. The chief constituent ore minerals of the former are smithsonite, calamine, hydrozincite and clay minerals changing to underlying country rocks at the depth of 10 to 50 meters from the surface, and no sulfide minerals are found. In some of the latter, however, outcrop of ore vein composed of sphalerite and galena was found, or drilling core rich in sphalerite was taken from the depth of several meters though the surface of the outcrop at the collar of the hole is entirely changed to carbonate and silicate of zinc.
The host rock of the deposits are mainly limestone and dolomite, but siliceous sandstone plays an important part in Main Ore Body. The deposits of secondary ore minerals immediately above the sulfides may mostly be oxidation products "in situ" type, but some amount of migration of oxidized ore constituents should have been taken place in the process of oxidation in Main Ore Body.
No igneous intrusives are known in the vicinity of several dozen kilometers, and the existence of zinc-lead deposits seems to be confined to the Mesozoic Kamawkala limestone which fringes the eastern boundary of Maesod basin.

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Since last November, the writers have been trying a new underground wire line drilling method, which is the first attempt in Japan.
This new underground wire line system differs from usual wire line systems at the point that in the former system the inner tube and the overshot are inserted with water pressure, whereas in the latter they are inserted with their own gravity. With this new system, a piston is set in the inner tube and the overshot which are made of iron rubber, and the water swivel has unique (special) mechanism. Consequently, this underground wire line system can be applied to the drilling in voluntary angle of slope as well as vertical, although usual wire line system has been limited its use only to the drilling in declination or steep incline.
Following are the test results of the first drilling with the new method.
1) Actual drilling time diminished from 22% to 19% by pulling up the inner tube again and again.
2) Efficiency was improved by 60-80% over the usual method (not usual wire line method).
3) Sometimes we had the troubles of cutting off latch spring and wire, and raising water pressure by crumbling the drilling hole of the clayey rock, etc.

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