The Misano and Utozaka uranium deposits in the eastern part of the Kani Basin, Gifu, occur within Miocene non-marine sediments which unconformably overlie Paleozoic-Mesozoic sediments and Cretaceous-Paleogene granites. These deposits are classified as sandstone-type deposits structually controlled by palaeo-channel structures formed on the pre-Miocene basement rocks.
The host rock is the Kani Lignite-bearing Formation which is the lowermost sequence of the Kani Group. The age of the formation is estimated to be 20-19 Ma on the basis of fission-track dating and is correlated to that of the Toki Lignite-bearing Formation which hosts the Tsukiyoshi uranium deposits in the Toki Basin. The mineralized host sediments consist of conglomerates, arkosic sandstones, tuffaceous sandstones and carbonaceous sandstones. Abundant organic material is associated with the mineralization in many cases and calcite cementation and/or veinlets are often observed as well. Pyrite is also an important mineral coexisting with the mineralization. Although no primary uranium minerals are identified to date, uramium is considered to be present as the uranous form.
The mineralization is strongly controlled by a fault structure within the basement granites as well as channel structures formed on the basement rocks especially on the granites. The enriched ore zone of the Misano deposit is distributed within the basal part of the Kani Lignite-bearing Formation above the basement fault structure and in the polaeo-channel downward from the fault structure. The basement granites is also mineralized along the fault structure.
The evidence indicates that groundwater leached uranium from the basement granites which then migrated along the fault structure into the host sediments to form the deposit.

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Power Reactor and Nuclear Fuel Development Corporation (PNC) is actively participating in several uranium exploration programs in the Athabasca Basin, Saskatchewan, Canada. Athabasca Basin hosts several large, very high-grade uranium deposits. These deposits generally have no surface expression and are spacially related to the unconformity between Helikian age sandstone and Aphebian age graphite-bearing metasedimentary basement. Outcrop exposure is very poor and geophysical surveys, particularly the time domain electromagnetic surveys (TDEM) are indispensably used to detect conductive lithologies for exploratory drilling.
Electromagnetic conductors related to uranium mineralization have been successfully delineated in areas where thickness of sandstone cover exceeds 500m. This paper describes successful usage of TDEM method on PNC operated Christie Lake project in the eastern part of the Athabasca Basin.

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The giant "Shinano vein" was discovered in 1986, at the southeastern-most part of the Toyoha vein swarm, by systematic underground diamong drillings for a target extracted from the polyascendant mineralization model. Its minable ore reserve is estimated to be approximately 4.5 million tons, with an average grade of 270 g/t silver, 0.7% copper, 2% lead and 13% zinc.
Subsequent exploration by crosscuts and drifts has revealed that the complicated occurrence of ore minerals is attributed to overlapped mineralization of several stages. The ores are classified into four types; pyrite ore, copper ore, zinc ore, and banded lead-zinc ore, each of which is characterized by different mineral assemblages and contents of minor element such as silver, indium, tin, cobalt, nickel, galium, etc.
A symmetrical zoning of ore types is recognized in the successive Soya, Izumo and Shinano veins. The core of the zoning is at the lowermost part of the Izumo vein, where pyrite ore is dominat. This suggests that the ore fluids which have been fed to the Izumo vein have flowed laterally toward both side of Soya and Shinano veins.
Active geothermal system is present in the Toyoha mining area, where some deep drills encountered rock temperatures as high as 230°C. Boiling thermal fluids discharge from the drill holes through the Shinano vein. In addition to the indicated late Pliocene to Pleistocene age of the ore formation, the chemical and isotopic similarities between present-day geothermal fluids in the Shinano vein and the ore fluids in fluid inclusions indicate that the current hydrothermal fluid is survived ore solution.

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The Hokusatsu district of southern Kyushu is known for its gold mineralization. Vein-type fracture systems similar to those in this district have been produced in scale-model experiments in which a diapir-like mass is pushed upward through an overlying brittle layer consisting of a sand-powdery cement mixture. Progressive development of the experimental fractures, combined with predicted behavior of natural fluid phases during gold-silver mineralization, lead to following hypothetical scenario for the mineralization.
Two collapse basins was formed in the northwestern and southeastern parts of the Hokusatsu district in the early Pleistocene. The middle part of these two collapse basins was subjected to tentional stress resulting in fracture systems trending NE-SW which is paralleled by the fringe of these collapse basins. These surface fractures were penetrated by meteoric water.
Above the magma diapir, a second system of fractures developed due to shouldering aside of the overlying crust. Mineralized hydrothermal solutions penetrated upward into these deeper fractures. Eventually, with continued rising of the magma diapir, the fracture systems (surface and deep) became connected, and the vein deposits were precipitated as the hydrothermal solutions were cooled by mixing with meteoric water.

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