著者
御幸 和則
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.45, no.249, pp.41-52, 1995-02-28 (Released:2009-06-12)
参考文献数
31
被引用文献数
4

The Kirishima geothermal area is located in the Kagoshima graben which is a volcanic-tectonic depression. The Ogiri geothermal field is one of the active geothermal zones in the Kirishima geothermal area. A thick pile of volcanic rocks of Pleistocene age, reaching 2, 500m in thickness, deposited in the area. These volcanic rocks overlie the Cretaceous basement rock of the Shimanto group which is depressed to a depth of more than 1, 300m in the area. Features of the geothermal resources in the Ogiri field are of the typical fracture type. The Ginyu fault accompanied by hot water reservoirs is the target for developing geothermal resources in the field.Geological surveys such as predicting underground temperatures, analysing fracture systems, clarifying permeable zone, calculating drilling depth intersecting the Ginyu fault and evaluating characteristics of the Ginyu fault reservoir have been made during the process of exploration and development in the area. The underground temperatures were predicted by the studies on the ditribution of alteration minerals and fluid inclusions. The fracture systems were analyzed by measuring thermo-remnant magnetism of the cores and mineral assembleges of the alteration minerals and quantity of the hydrothermal vein minerals in the cuttings. Based on the results of the fracture analysis, multiple regression analysis were efficiently used to estimate the subsurface location of the Ginyu fault.As a result of the geological surveys, all of the production wells drilled in the Ogiri field intersected the Ginyu fault reservoir successfully, and steam production equivalent to 30 MW of electricity could be secured. On the basis of the informations obtained, excellent reservoir models in the Ogiri field were developed.
著者
石原 舜三
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.56, no.1, pp.95-96, 2006-05-20 (Released:2009-06-12)
参考文献数
11
被引用文献数
4
著者
石原 舜三
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.62, no.1, pp.106-108, 2012 (Released:2013-08-01)
参考文献数
7
著者
八幡 正弘 黒沢 邦彦 大津 直 高橋 徹哉 戸間替 修一 川森 博史 毛利 元躬
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.44, no.1, pp.1-16, 1994-02-28
参考文献数
21
被引用文献数
3

Terrestrial volcanic products and lacustrine deposits of Middle Miocene to Pliocene age are widely distributed in the Monbetsu-Kamishihoro Graben which belongs to the Kuril Inner Arc. The Seta deposit located in the southern extremity of the Graben is classified into a hot spring gold deposit, based upon the modes of occurence.<BR>In the Seta mine area, Middle Pliocene lacustrine deposits of the Ashoro Formation which were accumulated in the Tokachi Basin unconformably covers Late Miocene to Early Pliocene terrestrial volcanic products of the Horokapiribetsugawa Formation. The lacustrine deposits are composed of sandstone, mudstone and siliceous deposits associated with a hot spring gold mineralization. A wide variety of sedimentary structure of the lacustrine deposits is observable in this area ; for detailed investigation, a logging of 80 meters of new diamond drill core (GSH-91-1) was necessary, which revealed the sedimentary structure of the basal part of the deposits and the relationship of the Horokapiribetsugawa and the Ashoro Formations. Siliceous deposits have been divided into 5 types, S-I to S-V. Silica is deposited as silica sinter (S-I) on land and/or temporally on shore near the water line, and also conducted into the cold lake water by the thermal water as a thin bedded siliceous deposit (S-II), because the silica gelation quickly proceeds under the influence of current or wave. The hydrothermal eruption broke up the underlying rocks for breccias like a clastic dike and, as a result, scattered breccias, so-called hydrothermat explosion breccias (S-IV) and/or the accidental silica blocks (S-III) in tuff and sandstone. When the hydrothermal eruption took place intermittently in shallow water, silica was deposited as silica complex deposit with sandstone and conglomerate (S-V)<BR>The hydrothermal activity has been divided into seven stages (I to VII). In the Stage I, just prior to form the lake, the acid hydrothermal activity, began, resulting in the silicified and argillized zones in the Horokapiribetsugawa Formation. Stage II, is characterized by the prevalence of hydrothermal explosion breccias on the land of the northern edge of the lake. As mixing of the ascending acid thermal water with the cold groundwater or interstitial water in the basal part of the lacustrine deposits and the argillized rocks of the Horokapiribetsugawa Formation just under the surface of unconformity, adularia formed in sandstone and argillized tuff breccia with kaolin minerals as an alteration product. In the Stages III and V, the hydrothermal activity increased and silica was deposited on the land and/or on the bottom of the lake resulted in silica sinter, thin, bedded siliceous deposit and siliceous complex deposit. Stages IV and VI-1 are similar to Stage II. It may be inferred that the hydrothermal activity was carried on the shore of the lake or the land. In the Stage IV-2, the silica sinter which deposited to a thickness of about 2 meters on land. The hydrothermal activity has silicified to the surrounding rocks and has formed vertical and horizontal quartz veins in these rocks. In the Stage Vll, the hydrothermal activity was attenuated.<BR>These spots of the hydrothermal activity moved from north to south associated with the gold mineralization.
著者
渡辺 寧
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.66, no.1, pp.27-34, 2016 (Released:2018-08-15)
参考文献数
27

A future perspective of the supply of mineral resources is discussed on the basis of the example of rare earth elements (REE). Rare earth elements have been produced from monazite, bastnäsite, and ionic clay ores mostly in China during the last two decades. However, Chinese resource nationalism over the production and export has made the supply of REE unstable in terms of price and quantity. A possible alternative REE source is phosphate ores, which contain a few amount of REE as impurities with some toxic and radioactive elements. Despite low in REE concentration in phosphate ores, more than 300,000 tons of REE (as oxides), which correspond to more than two times of present-day REE demand in the world, are included in the ores annually produced from the mines for fertilizer production. The recovery of REE with other impurities from phosphate ores is beneficial not only to produce REE but also to avoid pollution in farming lands. While our society shifts from the plundering one to the sustainable one, in which mineral resources would be completely recycled, it is desired to recover all the by-product elements from the major ores in order to decrease the impacts on the environment and trigger innovations in the manufacturing industry.
著者
島田 允堯
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.53, no.2, pp.161-172, 2003-12-04 (Released:2009-06-12)
参考文献数
89
被引用文献数
3

In the last decade, arsenic contaminated groundwater (>0.01 mg/L) has frequently been detected from place to place in Japan, and has caused serious social problems. The comprehensive surveys and researches have demonstrated that arsenic of natural origin dissolves from the aquifer to groundwater under specific environmental conditions. Concerning the aquifer geology, the arsenic-bearing groundwater is divided into S-type (sediment hosted type) and M-type (metamorphic rock hosted type). Meanwhile, from the viewpoint of dissociation mechanism, the arsenic contamination is classified into three types; .Type 1: Reductive dissolution of iron oxyhydroxide (goethite) and release of adsorbed arsenic into groundwater; Type 2: Oxidation of arsenic pyrite, and Type 3: Arsenic release by the decomposition of organic matter in an alluvial peat layer under reducing condition of the aquifer.Because arsenic takes various forms as source and sink in nature and is sensitive to the environmental conditions, it is important that we should consider the geochemical cycle of arsenic for elucidating the dissolution mechanism and also for the remediation of groundwater at the contaminated sites.
著者
島崎 英彦
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.59, no.1, pp.73-76, 2009 (Released:2010-06-22)
参考文献数
12
著者
志賀 美英
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.49, no.1, pp.47-62, 1999-02-28 (Released:2009-12-14)
参考文献数
40

After 1960s the demand of mineral resources has rapidly increased in industrially advanced countries. Since the countries depend on mineral-abundant developing countries for the most required mineral resources, they have a wide-range mineral policy for securing mineral resources steadily. They, in such straitened circumstances, have special interest in deepsea and Antarctic mineral resources. Although the potential of Antarctic mineral resources has been estimated with a wide uncertainty, it appears that the continent contains significant resources, as many previous investigators have pointed out.Antarctica is at present governed by the Antarctic Treaty, which went into effect on June 23, 1961. In June 1988, the Consultative Parties of the Antarctic Treaty (CPAT) adopted the Antarctic Mineral Resource Regime governing the exploration, development and production of Antarctic minerals. The Mineral Regime, however, was strongly resisted by international Non-Governmental Organisations (NGOs) concerned with the conservation of the Antarctic environment. On the other hand, the Non-Aligned Countries declared in the General Assembly of the United Nations that any mineral regime on Antarctica, in order to be of benefit to all mankind, should be negotiated with the full participation of all members of the international community. The Antarctic Mineral Regime, as well as the closed system of the Consultative Meeting by the CPAT, was censured also in many other conferences, e.g. the Conference of Heads of States or Governments of Non-Aligned Countries, the Council of Ministers of the Organisation of African Unity, the Council of Ministers of the League of Arab States, and the Islamic Summit Conference.Thus, the Antarctic Mineral Regime once adopted was upset in November 1989. The CPAT instead adopted the Protocol on Environmental Protection in October 1991. The protocol, which entered into force on January 14, 1998, prohibites any activity relating to mineral resources, other than scientific research, in Antarctica at least for fifty years. In the period of the protocol negotiation, some international environmental NGOs were invited as observers to the Consultative Meeting and played important roles as reliable partners of the CPAT in the constitution of the protocol.
著者
渡辺 寧
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.60, no.2, pp.103-122, 2010 (Released:2013-06-14)
参考文献数
63
著者
金沢 康夫 中嶋 輝允 高木 哲一
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.49, no.3, pp.203-216, 1999-12-31 (Released:2009-06-12)
参考文献数
35
被引用文献数
2

Recent geoscientific data and models for ore geneses of the Bayan Obo REE-Nb-Fe deposits, Inner Mongolia, China were reviewed. The rift system developed in the northern margin of the Sino-Korean massif during the Early-Middle Proterozoic era made a favorite tectonic setting for the depositions of Bayan Obo Group and the ore deposits. A variety of veins and dykes around the deposits occur in the footwall clastic rocks and the basement of migmatites. K-metasomatism and brecciation of hanging H9 shale indicate that the shale could serve as a sealing cap-rock for the deposits (DREW et al., 1992). Data of isotope ages from Sm-Nd, La-Ba, Rb-Sr, Th-Pb, Ar-Ar, and Re-Os methods suggest that there are at least three metallogenic periods: (1) 1, 700 - 1, 260 Ma (Middle Proterozoic); (2) 555 - 370 Ma (Caledonian); and (3) 343 - 298 Ma (Hercynian). In the three periods the first one is of the most important (BAI et al., 1996). C, O and S isotopic compositions together with mineral chemistry and field observations of the H8 dolostone and ore minerals indicate the following possibilities: (1) The dolostone belongs to normal sedimentary carbonate rocks and is not a magmatic carbonatite. (2) The original iron (hematite) ore bodies were formed syngenetically before REE-Nb mineralization. (3) The hydrothermal fluids with an alkaline-carbonatite chemistry were derived from the upper mantle, and printed the REE-Nb mineralization over the original iron bodies. The process of the above (2) and (3) is considered as a composite process of both crustal and mantle source mineralization (CAO et al., 1995). Many geochemical data and field observations are consistent with the composite model for the origins of the Bayan Obo deposit.
著者
中川 充 納 篤 山本 俊一郎 原田 武
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.45, no.254, pp.401-408, 1995-12-31 (Released:2009-06-12)
参考文献数
48
被引用文献数
1

Platinum-group elements (PGE) in nonmagnetic panned-out detrital samples from the northern Kamuikotan ophi-olitic complex, Hokkaido, was examined by neutron activation method. Their Cl-chondrite normalized PGE patterns are similar to those of ophiolitic host rocks and chromitite. Positive correlation between the iridium and chromium contents imply that iridium-series-PGE anomalies are probably due to chromite-hosted platinum-group minerals. Averaged PGE concentration in the samples from the central Hokkaido (Do-ou) region is almost eight times higher than that from the northern Hokkaido (Do-hoku) region. Based on the chemical analyses and the estimated reserve of chromite, total amounts of PGE included within placer chromite grains are estimated to be 17 kg in the northern Hokkaido, and 245 kg in the central Hokkaido.
著者
亀井 玄人
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.51, no.2, pp.145-151, 2001-12-15 (Released:2009-06-12)
参考文献数
26
被引用文献数
2

The groundwater of the Mobara gasfield in Boso peninsula, eastern Japan, contains considerable amount, around 100 mg/L, of iodine besides dissolved methane. Twelve groundwater samples from gas-producing wells to the aquifer within the Kazusa Group in Mobara and Naruto districts have been analyzed for iodine, pH, Eh, HCO3-, NH4+, SiO2(aq), δD, δ18O, δ13CCH4 and seventeen elements. There is a good correlation between the concentrations of the dissolved elements to those in marine algae. The principal source of the iodine is believed to be algae buried in the sediments and the iodine has been discharged to the porewater during decomposition of the tissue.The molar ratio of I-/Cl- in the groundwater increases from 1.0×103 to 2.2×103 with changing the depth from 2000 to 1000 meters below the surface and turns to decrease from 2.2×103 to 1.8×103 with going up from 1000 to 500 meters. This tendency may be caused by the variation of buried organisms due to changing the sedimentary environment. The observed variation in the ratio indicates that the iodine discharged in the pore fluid did not migrate significantly after the deposition of the formation.
著者
李 讃熙 朴 喜寅
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.45, no.253, pp.323-329, 1995

韓国,太白山鉱化帯北部に位置する屯田金鉱山には数種類のPb-Bi-Sb-S系鉱物(Sbコサライト,Sbヘイロフスキーアイト,Sbリリアナイト,Bi車骨鉱,(未詳Pb-Bi-Sb-S鉱物)が産出する.これらPb-Bi-Sb-S系鉱物は方鉛鉱,車骨鉱,四面銅鉱,黄鉄鉱,黄銅鉱,閃亜鉛鉱,エレクトラムなどからなる方鉛鉱に富む鉱石に比較的多量に産出する傾向がある.Sbコサライトの平均元素組成はPb;44.1,Bi;30.7,Sb;5.7,Ag;1.6,Cu;0.6,S;16.7重量%で,硫黄原子数5とした時の化学式はPb<SUB>2.08</SUB>(Bi<SUB>1.41</SUB>Sb<SUB>0.47</SUB>)<SUB>1.88</SUB>(Ag<SUB>0.15</SUB>Cu<SUB>0.15</SUB>)<SUB>0.27</SUB>S<SUB>5</SUB>で与えられる.Biブーランジェライトの平均元素組成はPb;55.5,Bi;6.5,Sb:19.3とS;18.2重量%で硫黄原子数11とした時の化学式はPb<SUB>5.18</SUB>(Bi<SUB>0.60</SUB>Sb<SUB>3.10</SUB>)<SUB>3.7</SUB>S<SUB>11</SUB>で与えられる.Sbリリアナイト,Sbヘイロフスキーアイト,未詳Pb-Bi-Sb-S鉱物の化学組成は,硫黄原子数を6,9,5とした場合,それぞれPb2.94(Ag<SUB>0.14</SUB>Cu<SUB>0.15</SUB>)<SUB>0.3</SUB>(Bi<SUB>1.54</SUB>Sb<SUB>0.40</SUB>)<SUB>1.94</SUB>S<SUB>6</SUB>, Pb<SUB>5.84</SUB>(Ag<SUB>0.15</SUB>Cu<SUB>0.15</SUB>)<SUB>0.3</SUB>(Bi<SUB>1.52</SUB>Sb<SUB>0.38</SUB>)<SUB>1.9</SUB>S<SUB>9</SUB> and Pb<SUB>2.12</SUB>(Ag<SUB>0.08</SUB>Cu<SUB>0.25</SUB>)<SUB>0.34</SUB>(Bi<SUB>0.76</SUB>Sb<SUB>0.93</SUB>)<SUB>1.69</SUB>Fe<SUB>0.23</SUB>S<SUB>5</SUB>である.Sbコサライト,未詳Pb-Bi-Sb-S鉱物およびBiブーランジェライトの化学組成はChang et al.(1980)によって合成されたSbコサライト(C相),Y<SUB>1</SUB>-Y<SUB>2</SUB>相,W相にそれぞれ相当する.アンテモンとビスマスは互いに相関することから,両元素は2PbS-Bi<SUB>2</SUB>S<SUB>3</SUB>-Sb<SUB>2</SUB>S<SUB>3</SUB>系において互いに置換しあっていることが明らかになった.最大Bi/(Bi+Sb)比はSbコサライトでは0.75,未詳Pb-Bi-Sb-S鉱物では0.45,Biブーランジェライトでは0.16であった.
著者
村上 浩康 佐藤 比奈子 石山 大三 石原 舜三
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.61, no.2, pp.129-137, 2011-05-25
参考文献数
23

High-grade REE ores containing acid-resistant minerals, which are common in the Nolans Bore REE-P-U deposit, Northern Territory, Australia, were analyzed by ICP-MS after decomposition of two different preparation methods before the analyses; Li-borate-fusion in a commercial laboratory and multi-acid digestion in our organization. The result derived from multi-acid digestion method shows higher values on LREE relative to the other fusion method, yet Y and Zr showed us higher values on the fusion method. The high-grade REE ores are enriched in light-REE, especially Ce, La and Nd, with a maximum total REE value around 7 wt %. The quantitative analysis by multi-acid digestion seems highly reliable for a wide range of REE concentration when using suitable dilution ratio and digestion sequence with several types of acids which could totally dissolve acid-resistant minerals such as monazite. On the other hand, analysis by Li-borate-fusion at a commercial laboratory potentially gives lower values than that of multi-acid digestion; a given sample is extremely concentrated in light REE. It is necessary to examine the upper as well as the lower detection limits by a conventional analytical method in a commercial laboratory.
著者
麻木 孝郎 末岡 慎也 深澤 秀明 伊東 靖彦 古野 正憲 長 久
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.54, no.1, pp.27-36, 2004-05-20 (Released:2009-06-12)
参考文献数
5
被引用文献数
1

Since 2001, Nittetsu Mining has been carrying out copper exploration activities in twenty-two promising areas in Northern Chile, which were extracted using ASTER image analysis. In these areas, Furano area in Region I has been selected as the most important target considering its high mineral potential inferred from the ASTER image analysis and its easy access.Furano area, covering 282km2, locates some 15km northwest of Cerro Colorado copper mine. Geology of the basement rocks mainly consists of lower Cretaceous andesite and Paleogene intrusive rocks. They are widely covered by ignimbrite and alluvium sediment of Tertiary to Quaternary age. The RC drilling program of 13 holes, totaling 3, 704m, was carried out on the prospective locations in the western part of the project area, which were selected by geological and geochemical surveys. Dominant copper and gold mineralizations were observed in some holes. Above all, a tourmaline breccia zone in silicified andesite showed average copper grade of 0.9% over the depth from 110m to 190m in one hole. The ore body shows 40m in width, dipping 55 degrees towards north, and is expected to be 400m continuation from the distribution of surface mineral occurrences. About 20 million tons of ore reserve was estimated above the depth of 300m. In another hole, drilled in ignimbrite-covered area, oxidized and corroded tourmaline breccia and underlying chalcopyrite-disseminated granite porphyry were observed. A secondary precipitation of chalcocite was also recognized in the lower part of the tourmaline breccia. These evidences suggest that the adjoining area covered by ignimbrite still has high potential for porphyry copper deposition. Additional drilling exploration is required around those holes.
著者
宮下 敦
出版者
The Society of Resource Geology
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.45, no.253, pp.313-321, 1995-10-31 (Released:2009-06-12)
参考文献数
36

Based on a compilation of geological and geophysical data, a new hypothesis is proposed for the formation of epithermal Au-Ag deposits in the Hokusatsu region, Kyushu, Japan. Several Plio-Pleistocene stratovolcanos in a graben with anortheasterly trend would have the following feature of gravity data:a regional low anomaly (-10mgal) corresponds to the graben being filled with low density sediments, and areal high anomalies (+30mgal) in the reagional low gravity correspond to the center of andesitic stratovolcanoes.In the Hokusatsu region, all stratovolcanic bodies are accompanied with one or more epithermal Au-Ag ore deposits. Veins of these deposits have a northeast orientation approximately perpendicular to the regional tensional stress orientation related to the opening of the Okinawa Trough.
著者
正路 徹也
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.61, no.3, pp.217-248, 2011-12-08
参考文献数
11

The 2011 earthquake off the Pacific coast of Tohoku and the following tsunami caused loss of a large number of lives, destruction of not only many private houses but also infrastructures, and the Fukushima I nuclear accidents, although disasters for the mineral and exploration world in Japan were not so serious. It is other sensational topics that gold prices have increased rapidly, and are higher than 1800 US$/oz in August, 2011, and that copper prices recorded the highest of 8966 $/t (LME) on November 11, 2010. Japanese mining, petroleum and trading companies and JOGMEC (Japan Oil, Gas and Metals National Corporation) continue their activities steadily, and get many fruitful results in exploration and development of mineral and energy resources, which have been carried out in these several years and decades. For example, Sumitomo Metal Mining Co., Ltd and Sumitomo Corporation have confirmed the presence of a gold, silver, and antimony mineralization zone in the Stone Boy project, Araska. Idemitsu Kosan Co., Ltd and JX Nippon Oil & Gas Exploration Corp. have been awarded independently and jointly many new exploration licences located in British and Norwegian North Sea, and conduct the exploration programs in some blocks as the operatores.
著者
石原 舜三
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.62, no.1, pp.106-108, 2012-03-05
参考文献数
7
著者
吉江 隆 大坪 徹 奥 直樹 上田 祐子
出版者
資源地質学会
雑誌
資源地質 (ISSN:09182454)
巻号頁・発行日
vol.65, no.2, pp.53-79, 2015

Pan Pacific Copper Co.,Ltd. (PPC) commenced intensive explorations for the Caserones copper-molybdenum deposit and its cluster deposits in 2006 just after the acquisition of property and confirmed more than one billion tons of resources in 2009. <br>Vertical mineral zonation related to weathering is distinctive in the Caserones deposit, which the oxidized and sulfide supergene enrichment zones are determined over the primary mineralization. <br>Primary Cu-Mo sulfide mineralization follows both spatially and temporally the intrusion of dacite porphyry (PDA), a NNW-SSE elongated dyke intruding into the Paleozoic monzogranite batholith and the breccia probably in close genetic relationship with PDA. Three stages of the mineralization are recognized. Early stage accompanies potassic alteration. Veins equivalent to EB and A in El Salvador occur in this stage. Quartz-sericite alteration is the most prominent alteration and dominated in the third stage which is also the most intensive period of veining of the so-called D-vein. The porphyry mineralization is overlapped by an epithermal-like mineralization (ZEP) which carries pyrite, chalcopyrite, galena and tennantite. Fluid inclusion study recognizes two types of inclusions, type Ⅰ(V+L+S) and type III(V+L, V<30%). Type Ⅰ inclusions show homogenization temperature ranging 283-463&deg;C and salinity between 31.8-44.4% NaCl eq. On the other hand, type III inclusions have temperature ranging 329-474&deg;C and salinity ranging 4.6-20.6% NaCl eq. Fluid inclusions of ZEP are characteristically low both in temperature and salinity, 200-288&deg;C and 2.9-7.4% NaCl eq respectively. Chronological study indicates 17-19 Ma for dacite porphyry, sericite and molybdenite.<br>Several prospects are known in the project area and they show common characteristics in geology with the Caserones deposit, while interpreted period of those magmatism and mineralization is possibly older than of the Caserones. Exploration for those deposits are still in reconnaissance stage, but some 100-200 million tons of sulfide potential is estimated for Cerro Sur prospect and some 40 million tons of oxide potential is expected for Angelica prospect.