Pub Date : 2013-12-12DOI: 10.22067/ECONG.V5I2.31716
عباس گل محمدی, محمدحسن کریم پور, آزاده ملکزاده شفارودی, سیداحمد مظاهری
Sangan magnetite skarn mine is located 300 km southeast of Mashhad, along the eastern part of Khaf-Drouneh volcanic-plutonic belt. Granitoids from three areas within the Sangan mine A, C-North and Dardvay were studied. Within the study area, three intrusive rocks including biotite-hornblende monzonite porphyry, biotite syenite and syenogranite were recognized. Based on field cross cutting, absence of garnet-magnetite skarn around the contact, and alteration by younger hydrothermal fluids, these granitoids are older than the magnetite skarn. U-Pb zircon age of the granitoid is 42 Ma (Middle Eocene). Magnetic susceptibility of the granitoids are 310-900 × 10-5 (SI units) and therefore, they are classified as belonging to the magnetite-series (oxidant type) I-type. Chemically, these granitoids are metaluminous, alkali-calcic to alkali and shoshonite to ultrapotassic. Enrichment of LREE, relative to HREE and enrichment of LILE (Sr, Cs, Rb, K and Ba) relative to HFSE (Nb, Ta, Ti, Hf and Zr) indicate that the magma formed in island arc setting. This magma originated from low partial melting (<1%) of garnet-spinel lherzolite (low garnet) and was contaminated in the continental crust. Based on the ratio of (La/Yb)N 6.23-34.73, indicate that small amount of garnet was left in the source rock. High ration of Rb/Sr, LILE/HFSE and high content of K2O, Th and Nb indicative of continental crust contamination. Petrognesis and geochronology of Sangan granitoid will help to know more about tectonomagmatic of Khaf-Kashmar-Drouneh volcanic-plutonic belt and their mineralization.
{"title":"پترولوژی و سن سنجی زیرکن به روش U-Pb در توده های نفوذی مناطق A، C جنوبی و دردوی، معدن سنگ آهن سنگان خواف","authors":"عباس گل محمدی, محمدحسن کریم پور, آزاده ملکزاده شفارودی, سیداحمد مظاهری","doi":"10.22067/ECONG.V5I2.31716","DOIUrl":"https://doi.org/10.22067/ECONG.V5I2.31716","url":null,"abstract":"Sangan magnetite skarn mine is located 300 km southeast of Mashhad, along the eastern part of Khaf-Drouneh volcanic-plutonic belt. Granitoids from three areas within the Sangan mine A, C-North and Dardvay were studied. Within the study area, three intrusive rocks including biotite-hornblende monzonite porphyry, biotite syenite and syenogranite were recognized. Based on field cross cutting, absence of garnet-magnetite skarn around the contact, and alteration by younger hydrothermal fluids, these granitoids are older than the magnetite skarn. U-Pb zircon age of the granitoid is 42 Ma (Middle Eocene). Magnetic susceptibility of the granitoids are 310-900 × 10-5 (SI units) and therefore, they are classified as belonging to the magnetite-series (oxidant type) I-type. Chemically, these granitoids are metaluminous, alkali-calcic to alkali and shoshonite to ultrapotassic. Enrichment of LREE, relative to HREE and enrichment of LILE (Sr, Cs, Rb, K and Ba) relative to HFSE (Nb, Ta, Ti, Hf and Zr) indicate that the magma formed in island arc setting. This magma originated from low partial melting (<1%) of garnet-spinel lherzolite (low garnet) and was contaminated in the continental crust. Based on the ratio of (La/Yb)N 6.23-34.73, indicate that small amount of garnet was left in the source rock. High ration of Rb/Sr, LILE/HFSE and high content of K2O, Th and Nb indicative of continental crust contamination. Petrognesis and geochronology of Sangan granitoid will help to know more about tectonomagmatic of Khaf-Kashmar-Drouneh volcanic-plutonic belt and their mineralization.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"5 1","pages":"155-174"},"PeriodicalIF":0.0,"publicationDate":"2013-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68565211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arghash – Ghasem-Abad area in NE Iran is located in the rim of the Sabzevar structural zone. Tertiary outcrops include granite and quartz monzodiorite porphyry associated with dacite and andesite volcanic rocks. In the study area, quartz gabbro and quartz monzodiorite dykes intruded the older rocks. Granite and volcanic rocks host Au-Sb-bearing quartz-calcite veins. Mineralized veins are mainly located around the dykes in the southern part of the area. According to geochemical studies, granites have high-K calc-alkaline affinity with transitional I/A-type features. The volcanic rocks with adakitic composition contain high abundances of Sr and Ba. The dykes in the area show characteristics of lamprophyric rocks. U-Pb zircon dating of granite yielded an age of 55.4±2.2 Ma (Lower Eocene). Initial 87Sr/86Sr and eNd values for the granites are 0.704142 and +5.84, respectively. Initial 87Sr/86Sr ratios strongly suggest a depleted mantle source for the magma. This dating demonstrates that the Au-Sb mineralization occurred later than Lower Eocene. Based on field observation, the mineralization is more related to the lamprophyric dykes than to the adakitic rocks.
{"title":"پترولوژی، ژئوشیمی و کانی سازی سنگهای آتشفشانی ترشیری و توده های نفوذی و نیمه نفوذی همراه آنها در منطقه ارغش- قاسمآباد (شمالشرق ایران) با گرایشی ویژه به سن و منشأ گرانیت ها","authors":"زهرا اعلمی نیا, محمدحسن کریم پور, سیدمسعود همام, فریتز فینگر","doi":"10.22067/ECONG.V5I1.22841","DOIUrl":"https://doi.org/10.22067/ECONG.V5I1.22841","url":null,"abstract":"Arghash – Ghasem-Abad area in NE Iran is located in the rim of the Sabzevar structural zone. Tertiary outcrops include granite and quartz monzodiorite porphyry associated with dacite and andesite volcanic rocks. In the study area, quartz gabbro and quartz monzodiorite dykes intruded the older rocks. Granite and volcanic rocks host Au-Sb-bearing quartz-calcite veins. Mineralized veins are mainly located around the dykes in the southern part of the area. According to geochemical studies, granites have high-K calc-alkaline affinity with transitional I/A-type features. The volcanic rocks with adakitic composition contain high abundances of Sr and Ba. The dykes in the area show characteristics of lamprophyric rocks. U-Pb zircon dating of granite yielded an age of 55.4±2.2 Ma (Lower Eocene). Initial 87Sr/86Sr and eNd values for the granites are 0.704142 and +5.84, respectively. Initial 87Sr/86Sr ratios strongly suggest a depleted mantle source for the magma. This dating demonstrates that the Au-Sb mineralization occurred later than Lower Eocene. Based on field observation, the mineralization is more related to the lamprophyric dykes than to the adakitic rocks.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"5 1","pages":"1-22"},"PeriodicalIF":0.0,"publicationDate":"2013-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68565130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-10-12DOI: 10.22067/ECONG.V4I2.16500
زهرا خالدی, حسین محمدزاده
The presence of Cr(VI) in groundwater resources is governed by pH and Eh of water and its compounds are generally soluble and have more toxicicity and mobility in oxidizing environments. In this article, the Cr concentration in ophiolite units, in sediments, and in groundwater resources, and also its potential to contaminate the environment have been investigated in southeast of Birjand. During sampling, 17 water samples (2 rain water samples and 15 groundwater samples), and 8 sediment samples were collected. The concentrations of cations (major cations and Cr) and anions in water samples were measured at Ottawa University, Canada using IC and ICP-AES methods, respectively. Cr concentrations of sediments were measured using XRF, and concentrations of Cr in collected Selective Sequential Extraction (SSE) fractions were measured using Atomic Absorption (AA) at Ferdowsi University of Mashhad, Iran. The average Cr concentrations in sediments and water resources are 627 and 0.026 ppm, respectively. According to the pH of sediments and Eh-pH of water samples, the Cr in water resources is as Cr(VI). Furthermore, the results of SSE show that the majority of Cr was found with residual matter, attached to the iron and manganese oxides, bound to carbonates, organic matter, and the soluble fractions, respectively. The hydrogeochemical properties of water resources show that the average values of EC, TDS and pH are 509 mg/l, 1045 µs/cm and 8.1, respectively, and the concentrations of Cl-, Na+, Mg2+ and SO42- ions are higher than the levels of WHO and Iran National Standard (1053). According to the WQI classification, while 20 percent of the water resources have excellent quality, 53 percent show good quality and 20 percent of water resources are poor in quality.
{"title":"ارزیابی کروم افیولیت ها و آبهای زیرزمینی و پتانسیل آلایندگی زیست محیطی آن در جنوب شرقی بیرجند","authors":"زهرا خالدی, حسین محمدزاده","doi":"10.22067/ECONG.V4I2.16500","DOIUrl":"https://doi.org/10.22067/ECONG.V4I2.16500","url":null,"abstract":"The presence of Cr(VI) in groundwater resources is governed by pH and Eh of water and its compounds are generally soluble and have more toxicicity and mobility in oxidizing environments. In this article, the Cr concentration in ophiolite units, in sediments, and in groundwater resources, and also its potential to contaminate the environment have been investigated in southeast of Birjand. During sampling, 17 water samples (2 rain water samples and 15 groundwater samples), and 8 sediment samples were collected. The concentrations of cations (major cations and Cr) and anions in water samples were measured at Ottawa University, Canada using IC and ICP-AES methods, respectively. Cr concentrations of sediments were measured using XRF, and concentrations of Cr in collected Selective Sequential Extraction (SSE) fractions were measured using Atomic Absorption (AA) at Ferdowsi University of Mashhad, Iran. The average Cr concentrations in sediments and water resources are 627 and 0.026 ppm, respectively. According to the pH of sediments and Eh-pH of water samples, the Cr in water resources is as Cr(VI). Furthermore, the results of SSE show that the majority of Cr was found with residual matter, attached to the iron and manganese oxides, bound to carbonates, organic matter, and the soluble fractions, respectively. The hydrogeochemical properties of water resources show that the average values of EC, TDS and pH are 509 mg/l, 1045 µs/cm and 8.1, respectively, and the concentrations of Cl-, Na+, Mg2+ and SO42- ions are higher than the levels of WHO and Iran National Standard (1053). According to the WQI classification, while 20 percent of the water resources have excellent quality, 53 percent show good quality and 20 percent of water resources are poor in quality.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"4 1","pages":"335-350"},"PeriodicalIF":0.0,"publicationDate":"2012-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68565042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-10-12DOI: 10.22067/ECONG.V4I2.16489
محمد علی جزی, محمدحسن کریم پور, آزاده ملکزاده شفارودی
One of the most intensive occurrences of magmatism in Iran was in the middle Jurassic period. Among the granitoid intrusions in this period as discrete bodies or complexes can be pointed to Aligoodarz, Alvand, Astaneh, Boroujerd, Malayer, and Chah-Dozdan in the Sanandaj-Sirjan zone; Shir-kuh and Ayrakan in the Central Iran zone; Shah-kuh, Sorkh-kuh and Kalateh-Ahani in the Lut Block. These granitoids are mostly peraluminous and belong to high-K calc-alkaline series. CaO/Na2O ratios (0.12 to 8.37) mostly suggest a clay-free source for formation of the intrusive rocks magma. Chondrite-normalized Rare Earth Elements (REEs) diagram do not display high enrichment of Light Rare Earth Elements (LREEs) than Heavy Rare Earth Elements (HREEs) and general pattern is relatively flat. In addition, diagram shows Eu negative anomaly, which can be attributed to indicate reducing conditions in formation of magma and/or magma derived from plagioclase depth as source. The lower continental crust-normalized spider diagram indicates enrichment in LILE (Rb, Cs, and K) and LREE (La and Ce) and depletion in Ba, Nb, Ta, Sr, and Ti. Initial 87Sr/86Sr ratios are 0.70609 to 0.71938 and initial eNd values are negative (from -6.51 to -1.1) indicating that magma derived from continental crust. Geochemical and isotopic evidence of the intrusive rocks shows continental crust origin (S-type granitoid) and due to continental collision. Geological findings such as stop in sedimentation, regional metamorphism, ophiolite displacement, and continental collision-related mineralization confirm continental collision between Iranian and Arabian plates in the Middle Jurassic period.
{"title":"مروری بر ژئوشیمی و ایزوتوپ Rb/Sr و Sm/Nd تودههای نفوذی گرانیتوئیدی ژوراسیک میانی و ترشیاری: دیدگاهی نوین بر تکتونو- ماگماتیسم و کانی سازی این دوره زمانی ایران","authors":"محمد علی جزی, محمدحسن کریم پور, آزاده ملکزاده شفارودی","doi":"10.22067/ECONG.V4I2.16489","DOIUrl":"https://doi.org/10.22067/ECONG.V4I2.16489","url":null,"abstract":"One of the most intensive occurrences of magmatism in Iran was in the middle Jurassic period. Among the granitoid intrusions in this period as discrete bodies or complexes can be pointed to Aligoodarz, Alvand, Astaneh, Boroujerd, Malayer, and Chah-Dozdan in the Sanandaj-Sirjan zone; Shir-kuh and Ayrakan in the Central Iran zone; Shah-kuh, Sorkh-kuh and Kalateh-Ahani in the Lut Block. These granitoids are mostly peraluminous and belong to high-K calc-alkaline series. CaO/Na2O ratios (0.12 to 8.37) mostly suggest a clay-free source for formation of the intrusive rocks magma. Chondrite-normalized Rare Earth Elements (REEs) diagram do not display high enrichment of Light Rare Earth Elements (LREEs) than Heavy Rare Earth Elements (HREEs) and general pattern is relatively flat. In addition, diagram shows Eu negative anomaly, which can be attributed to indicate reducing conditions in formation of magma and/or magma derived from plagioclase depth as source. The lower continental crust-normalized spider diagram indicates enrichment in LILE (Rb, Cs, and K) and LREE (La and Ce) and depletion in Ba, Nb, Ta, Sr, and Ti. Initial 87Sr/86Sr ratios are 0.70609 to 0.71938 and initial eNd values are negative (from -6.51 to -1.1) indicating that magma derived from continental crust. Geochemical and isotopic evidence of the intrusive rocks shows continental crust origin (S-type granitoid) and due to continental collision. Geological findings such as stop in sedimentation, regional metamorphism, ophiolite displacement, and continental collision-related mineralization confirm continental collision between Iranian and Arabian plates in the Middle Jurassic period.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"4 1","pages":"171-198"},"PeriodicalIF":0.0,"publicationDate":"2012-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68565014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tertiary intrusive granitoids within the Lut block in the Khorasan Razavi and South Khorasan provinces are mainly sub-volcanic with porphyry texture and their composition varies from granite to diorite but monzonite is dominant. With the exception of Hired, these are classified as belonging to the magnetite-series of I-type granitoids. Chemically, these rocks are meta-aluminous. Those with mineralization are K-rich and those without mineralization such as Najmabad are Na-rich. All intrusive rocks plot in the field of calc-alkaline to adakite except Najmabad that plot in the adakite field. Based on low content of Nb ( 30), low initial 87Sr/86Sr ( 17 ppm), low ratio of Zr/Nb ( 0.707) and low initial eNd value (-3), magmas in the Kaybar-Kuh were more contaminated in the continental crust. Based on depletion in HREE and high ratio of (La/Yb)N (17-23), magma in Najmabad originated in the deep region in which garnet was present. Based on REE pattern and ration of Eu/Eu* (0.8-1), intrusive rocks within Maherabad, Khoopik, Chah-Shaljami, Kuh Shah and Dehsalm are calc-alkaline and their magma formed in an oxidant condition whereas Kaybar Kuh magma with low ratio of Eu/Eu* (<0.8) was contaminated in the continental crust under reduced conditions. The age of these granitoids is between Middle Eocene and Lower Oligocene. Kaybar-Kuh (43.3 Ma) is situated in the north and Chah-Shaljami (33.3 Ma) in the south. The initial 87Sr/86Sr ratios decrease from north (0.7077) to south (0.7047) as the age decreases. eNd of Maherabad, Khoopik, Dehsalm, and Chah-Shaljami granitoids is between +0.5 and +2.49 and the initial 87Sr/86Sr ratio is less than 0.7055. The age of the source rock (TDM, which was calculated based on Sm-Nd isotopes) indicates that these magma originated from oceanic crust with different ages. Kaybar-Kuh originated from the oldest oceanic crust (840 Ma) and was contaminated more in continental crust, but Najmabad originated from a younger oceanic crust (360 Ma) with minor contamination. Dehsalm and Chah-Shaljami magma which had some differences with Maherabad and Khoopik, originated from oceanic crust of 200 Ma. The period between 42 and 33 Ma (Middle Eocene to Lower Oligocene) is the most important stage of mineralization in eastern Iran especially in South Khorasan. Some of the major systems, which are identified so far are: porphyry Cu-Au, reduced intrusive related Au, high sulfidation Au, Fe- skarn, Pb-Zn-Sb vein and IOCG deposits. Granitoid rocks formed between 42 and 33 Ma within the Lut block and northern area has great potential for exploring porphyry Cu-Au, IOCG, Fe, Pb-Zn, Au etc.
{"title":"پتروژنز گرانیتوئیدها، سن سنجی زیرکن به روشU-Pb ، ژئوشیمی ایزوتوپ های Sr- Nd و رخداد مهم کانی سازی ترشیاری در بلوک لوت، شرق ایران","authors":"محمدحسن کریم پور, آزاده ملکزاده شفارودی, جی لنگ فارمر, چارلز استرن","doi":"10.22067/ECONG.V4I1.13391","DOIUrl":"https://doi.org/10.22067/ECONG.V4I1.13391","url":null,"abstract":"Tertiary intrusive granitoids within the Lut block in the Khorasan Razavi and South Khorasan provinces are mainly sub-volcanic with porphyry texture and their composition varies from granite to diorite but monzonite is dominant. With the exception of Hired, these are classified as belonging to the magnetite-series of I-type granitoids. Chemically, these rocks are meta-aluminous. Those with mineralization are K-rich and those without mineralization such as Najmabad are Na-rich. All intrusive rocks plot in the field of calc-alkaline to adakite except Najmabad that plot in the adakite field. Based on low content of Nb ( 30), low initial 87Sr/86Sr ( 17 ppm), low ratio of Zr/Nb ( 0.707) and low initial eNd value (-3), magmas in the Kaybar-Kuh were more contaminated in the continental crust. Based on depletion in HREE and high ratio of (La/Yb)N (17-23), magma in Najmabad originated in the deep region in which garnet was present. Based on REE pattern and ration of Eu/Eu* (0.8-1), intrusive rocks within Maherabad, Khoopik, Chah-Shaljami, Kuh Shah and Dehsalm are calc-alkaline and their magma formed in an oxidant condition whereas Kaybar Kuh magma with low ratio of Eu/Eu* (<0.8) was contaminated in the continental crust under reduced conditions. \u0000The age of these granitoids is between Middle Eocene and Lower Oligocene. Kaybar-Kuh (43.3 Ma) is situated in the north and Chah-Shaljami (33.3 Ma) in the south. The initial 87Sr/86Sr ratios decrease from north (0.7077) to south (0.7047) as the age decreases. eNd of Maherabad, Khoopik, Dehsalm, and Chah-Shaljami granitoids is between +0.5 and +2.49 and the initial 87Sr/86Sr ratio is less than 0.7055. The age of the source rock (TDM, which was calculated based on Sm-Nd isotopes) indicates that these magma originated from oceanic crust with different ages. Kaybar-Kuh originated from the oldest oceanic crust (840 Ma) and was contaminated more in continental crust, but Najmabad originated from a younger oceanic crust (360 Ma) with minor contamination. Dehsalm and Chah-Shaljami magma which had some differences with Maherabad and Khoopik, originated from oceanic crust of 200 Ma. \u0000The period between 42 and 33 Ma (Middle Eocene to Lower Oligocene) is the most important stage of mineralization in eastern Iran especially in South Khorasan. Some of the major systems, which are identified so far are: porphyry Cu-Au, reduced intrusive related Au, high sulfidation Au, Fe- skarn, Pb-Zn-Sb vein and IOCG deposits. Granitoid rocks formed between 42 and 33 Ma within the Lut block and northern area has great potential for exploring porphyry Cu-Au, IOCG, Fe, Pb-Zn, Au etc.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"4 1","pages":"1-27"},"PeriodicalIF":0.0,"publicationDate":"2012-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68564896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-25DOI: 10.22067/ECONG.V4I1.13394
مریم عبدی, محمدحسن کریم پور
The Kuh Shah prospecting area is located in Tertiary volcano-plutonic belt of the Lut Block. More than seventeen subvolcanic intermediate to acidic intrusive rocks, diorite to syenite in composition, were identified in the study area. The intrusions are related to hydrothermal alteration zones and contain argillic, propylitic, advanced argillic, silicified, quartz-sericite-pyrite, gossan and hydrothermal breccia which overprinted to each other and are accompanied by weathering which made it complicated to distinguish zoning. Mineralization is observed as sulfide (pyrite and rare chalcopyrite), disseminated Fe-oxides and quartz-Fe-oxide stockwork veinlets. Intrusive rocks are metaluminous, calc-alkaline with shoshonitic affinity with high values of magnetic susceptibility. The Kuh Shah intrusive rocks are classified as magnetite-series of oxidant I-type granitoids. Based on zircon U–Pb age dating, the age of these granitoid rocks is 39.7± 0.7 Ma (Middle Eocene). The radioisotope data (initial 87Sr/86Sr and 143Nd/144Nd ratios as well as eNd) and geochemical data suggest that the Kuh Shah granitoid rocks formed from depleted mantle in a subduction-related magmatic arc setting. Geochemical anomalies of elements such as Cu, Au, Fe, Pb, Zn, As, Sb, Mo, Bi, Hg and also Mn, Ba, Te and Se, correlated with quartz-sericite-pyrite, gossan-stockwork-hydrothermal breccias, irregular silicified bodies and advanced argillic hydrothermal alteration zones. Geophysical anomalies correlated with hydrothermal alteration and mineralization zones. The interpretation of the results represents complex patterns of sub-circular to ellipsoid shape with north-east to south-west direction. These evidences are similar to the other for known Cu-Au porphyry and Au-epithermal systems in Iran and worldwide.
{"title":"زمین شناسی، دگرسانی، کانه زایی، پتروژنز، سن سنجی، ژئوشیمی و ژئوفیزیک هوابرد منطقه اکتشافی کوه شاه، جنوب غرب بیرجند","authors":"مریم عبدی, محمدحسن کریم پور","doi":"10.22067/ECONG.V4I1.13394","DOIUrl":"https://doi.org/10.22067/ECONG.V4I1.13394","url":null,"abstract":"The Kuh Shah prospecting area is located in Tertiary volcano-plutonic belt of the Lut Block. More than seventeen subvolcanic intermediate to acidic intrusive rocks, diorite to syenite in composition, were identified in the study area. The intrusions are related to hydrothermal alteration zones and contain argillic, propylitic, advanced argillic, silicified, quartz-sericite-pyrite, gossan and hydrothermal breccia which overprinted to each other and are accompanied by weathering which made it complicated to distinguish zoning. Mineralization is observed as sulfide (pyrite and rare chalcopyrite), disseminated Fe-oxides and quartz-Fe-oxide stockwork veinlets. Intrusive rocks are metaluminous, calc-alkaline with shoshonitic affinity with high values of magnetic susceptibility. The Kuh Shah intrusive rocks are classified as magnetite-series of oxidant I-type granitoids. Based on zircon U–Pb age dating, the age of these granitoid rocks is 39.7± 0.7 Ma (Middle Eocene). The radioisotope data (initial 87Sr/86Sr and 143Nd/144Nd ratios as well as eNd) and geochemical data suggest that the Kuh Shah granitoid rocks formed from depleted mantle in a subduction-related magmatic arc setting. Geochemical anomalies of elements such as Cu, Au, Fe, Pb, Zn, As, Sb, Mo, Bi, Hg and also Mn, Ba, Te and Se, correlated with quartz-sericite-pyrite, gossan-stockwork-hydrothermal breccias, irregular silicified bodies and advanced argillic hydrothermal alteration zones. Geophysical anomalies correlated with hydrothermal alteration and mineralization zones. The interpretation of the results represents complex patterns of sub-circular to ellipsoid shape with north-east to south-west direction. These evidences are similar to the other for known Cu-Au porphyry and Au-epithermal systems in Iran and worldwide.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"4 1","pages":"77-107"},"PeriodicalIF":0.0,"publicationDate":"2012-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68564983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-02-12DOI: 10.22067/ECONG.V3I2.11420
محمدحسن کریم پور, آزاده ملکزاده شفارودی, اکبر اسفندیارپور, حسن محمدنژاد
Neyshabour turquoise mine is located in northwest of Neyshabour, southern Quchan volcanic belt. Eocene andesite and dacite forming as lava and pyroclastic rocks cover most of the area. Subvolcanic diorite to syenite porphyry (granitoids of magnetite series) intruded the volcanic rocks. Both volcanic and subvolcanic rocks are highly altered. Four types of alteration are recognized including: silicification, argillic, calcification and propylitic. Silicification is dominant followed by argillic alteration. Mineralization is present as stockwork, disseminated and hydrothermal breccia. Hypogene minerals are pyrite, magnetite, specularite, chalcopyrite, and bornite. Secondary minerals are turquoise, chalcocite, covellite, and iron oxides. A broad zone of gossan has developed in the area. Oxidized zone has a thickness of about 80 m. Mineralized samples show high anomalies of Cu, Au, Zn, As, Mo, Co, U, LREE, Nb, and Th. Both aeromagnetic and radiometric (U and Th) maps show very strong anomalies (10 × 5km) within the mineralized area. Based on geology, alteration, mineralization, geochemistry, and geophysics, Neyshabour turquoise mine is a large Iron oxide Cu-Au-U-LREE (IOCG) mineralized system. In comparison with other IOCG deposits, it has some similarities with Olympic Dam (Australia) and Candelaria (Chile). In comparison with Qaleh Zari and Kuh Zar mines, Neyshabour turquoise mine is the first Iron oxide Cu-Au-U-LREE (IOCG) mineralized system discovered in Iran.
{"title":"معدن فیروزه نیشابور: نخستین کانی سازی مس- طلا- اورانیم- عناصر نادر خاکی سبک نوع IOCG در ایران","authors":"محمدحسن کریم پور, آزاده ملکزاده شفارودی, اکبر اسفندیارپور, حسن محمدنژاد","doi":"10.22067/ECONG.V3I2.11420","DOIUrl":"https://doi.org/10.22067/ECONG.V3I2.11420","url":null,"abstract":"Neyshabour turquoise mine is located in northwest of Neyshabour, southern Quchan volcanic belt. Eocene andesite and dacite forming as lava and pyroclastic rocks cover most of the area. Subvolcanic diorite to syenite porphyry (granitoids of magnetite series) intruded the volcanic rocks. Both volcanic and subvolcanic rocks are highly altered. Four types of alteration are recognized including: silicification, argillic, calcification and propylitic. Silicification is dominant followed by argillic alteration. Mineralization is present as stockwork, disseminated and hydrothermal breccia. Hypogene minerals are pyrite, magnetite, specularite, chalcopyrite, and bornite. Secondary minerals are turquoise, chalcocite, covellite, and iron oxides. A broad zone of gossan has developed in the area. Oxidized zone has a thickness of about 80 m. Mineralized samples show high anomalies of Cu, Au, Zn, As, Mo, Co, U, LREE, Nb, and Th. Both aeromagnetic and radiometric (U and Th) maps show very strong anomalies (10 × 5km) within the mineralized area. Based on geology, alteration, mineralization, geochemistry, and geophysics, Neyshabour turquoise mine is a large Iron oxide Cu-Au-U-LREE (IOCG) mineralized system. In comparison with other IOCG deposits, it has some similarities with Olympic Dam (Australia) and Candelaria (Chile). In comparison with Qaleh Zari and Kuh Zar mines, Neyshabour turquoise mine is the first Iron oxide Cu-Au-U-LREE (IOCG) mineralized system discovered in Iran.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"3 1","pages":"193-216"},"PeriodicalIF":0.0,"publicationDate":"2012-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68565331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-12DOI: 10.22067/ECONG.V3I1.11439
آزاده ملکزاده شفارودی, محمدحسن کریم پور
شرق ایران بهواسطه رژیم تکتونیکی زون فرورانش در گذشته که به فعالیتهای ماگماتیسمی آلکالن تا کالکآلکالن گسترده در زمان ترشیری انجامیده است، پتانسیل خوبی برای تشکیل کانسارهای مس پورفیری دارد. ماهرآباد اولین منطقه اکتشافی مس- طلای پورفیری بوده که در شرق ایران کشف شده است. این کانسار وابسته به یک سری استوک های پورفیری مونزونیتی تا دیوریتی است که درون سنگهای آتشفشانی جایگزین شده اند. پورفیریهای مونزونیتی، نقش اساسی را در کانیسازی داشته اند. زونهای دگرسانی گسترده ای شامل پتاسیک، سریسیتیک- پتاسیک، کوارتز- سریسیت- کربنات- پیریت، کوارتز- کربنات- پیریت، سیلیسی- پروپیلیتیک، پروپیلیتیک، کربناته و سیلیسی وجود دارد. کانی سازی به حالتهای افشان، استوک ورک و برش هیدروترمالی اتفاق افتاده است. براساس اکتشاف اولیه، مس بین 179 تا 6830 گرم در تن (میانگین 3200 گرم در تن) و طلا بیش از 1000 میلی گرم در تن (میانگین 570 میلی گرم در تن) وجود دارد. این منطقه اکتشافی یک ذخیره مس پورفیری غنی از طلاست. سن سنجی لیزر- ابلیشن اورانیم- سرب روی دو نمونه از توده های نفوذی مرتبط با کانی سازی نشان می دهد که پورفیریهای مونزونیتی در 8/0 ± 39 تا 8/0 ± 2/38 میلیون سال پیش در فاصله زمانی کمتر از یک میلیون سال در ائوسن میانی متبلور شده اند. این اولین سن دقیق را برای دوره کانی سازیهای نوع پورفیری مشخص می کند. همچنین نسبت ایزوتوپ اولیه (87Sr/86Sr)i و i(143Nd/144Nd) اولیه با توجه به سن 39 میلیون سال محاسبه شد. نسبت ایزوتوپ اولیه (87Sr/86Sr)i در توده های مونزونیتی بین 7047/0 تا 7048/0 بوده است. نسبت (143Nd/144Nd)i اولیه نیز بین 512694/0 تا 512713/0 میباشد. میزان eNd اولیه بین 45/1 تا 81/1 است. براساس داده های ایزوتوپی منشاء ماگمای اولیه خارج از پوسته قاره ای بوده است. این پژوهش می تواند برای بررسی جایگاه تکتونو- ماگماتیکی و تکامل شرق ایران مورد استفاده قرار گیرد.
{"title":"سن سنجی زیرکان به روش اورانیم- سرب در منطقه اکتشافی مس- طلا پورفیری ماهرآباد: شاهدی بر دوره متالوژنیک ائوسن میانی ذخایر پورفیری در شرق ایران","authors":"آزاده ملکزاده شفارودی, محمدحسن کریم پور","doi":"10.22067/ECONG.V3I1.11439","DOIUrl":"https://doi.org/10.22067/ECONG.V3I1.11439","url":null,"abstract":"شرق ایران بهواسطه رژیم تکتونیکی زون فرورانش در گذشته که به فعالیتهای ماگماتیسمی آلکالن تا کالکآلکالن گسترده در زمان ترشیری انجامیده است، پتانسیل خوبی برای تشکیل کانسارهای مس پورفیری دارد. ماهرآباد اولین منطقه اکتشافی مس- طلای پورفیری بوده که در شرق ایران کشف شده است. این کانسار وابسته به یک سری استوک های پورفیری مونزونیتی تا دیوریتی است که درون سنگهای آتشفشانی جایگزین شده اند. پورفیریهای مونزونیتی، نقش اساسی را در کانیسازی داشته اند. زونهای دگرسانی گسترده ای شامل پتاسیک، سریسیتیک- پتاسیک، کوارتز- سریسیت- کربنات- پیریت، کوارتز- کربنات- پیریت، سیلیسی- پروپیلیتیک، پروپیلیتیک، کربناته و سیلیسی وجود دارد. کانی سازی به حالتهای افشان، استوک ورک و برش هیدروترمالی اتفاق افتاده است. براساس اکتشاف اولیه، مس بین 179 تا 6830 گرم در تن (میانگین 3200 گرم در تن) و طلا بیش از 1000 میلی گرم در تن (میانگین 570 میلی گرم در تن) وجود دارد. این منطقه اکتشافی یک ذخیره مس پورفیری غنی از طلاست. سن سنجی لیزر- ابلیشن اورانیم- سرب روی دو نمونه از توده های نفوذی مرتبط با کانی سازی نشان می دهد که پورفیریهای مونزونیتی در 8/0 ± 39 تا 8/0 ± 2/38 میلیون سال پیش در فاصله زمانی کمتر از یک میلیون سال در ائوسن میانی متبلور شده اند. این اولین سن دقیق را برای دوره کانی سازیهای نوع پورفیری مشخص می کند. همچنین نسبت ایزوتوپ اولیه (87Sr/86Sr)i و i(143Nd/144Nd) اولیه با توجه به سن 39 میلیون سال محاسبه شد. نسبت ایزوتوپ اولیه (87Sr/86Sr)i در توده های مونزونیتی بین 7047/0 تا 7048/0 بوده است. نسبت (143Nd/144Nd)i اولیه نیز بین 512694/0 تا 512713/0 میباشد. میزان eNd اولیه بین 45/1 تا 81/1 است. براساس داده های ایزوتوپی منشاء ماگمای اولیه خارج از پوسته قاره ای بوده است. این پژوهش می تواند برای بررسی جایگاه تکتونو- ماگماتیکی و تکامل شرق ایران مورد استفاده قرار گیرد.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"3 1","pages":"41-60"},"PeriodicalIF":0.0,"publicationDate":"2011-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68565278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-08DOI: 10.22067/econg.v2i1.3676
محدثه پناهی شهری, محمدحسن کریم پور, فاطمه شبانی
The investigated area is located 30 Km south of Sabzevar in Halakabad village. Geological phenomenons in area follow a trend of NW-SE. Mineralization consists of metallic and non-metallic (kaolin) mineralization. Disseminated and veinlet mineralization is generally associated with argillic alteration type. Pyrite is the most widespread type of sulfide mineralization in Halakabad occurrences. It usually displays a euhedral habit and have occurred at least in two generations. Calcopyrite is common in veinlets although in minor amounts. Secondary sulfuric acid weathering of the ore has generated huge surficial amounts of oxide and sulfate minerals which of hematite and jarosite are the most abundant. Geochemical exploration was conducted over both drainage geochemistry and rock geochemistry. Results show that some of the stream sediments have higher concentrations of Copper and Zinc than normal. This anomalies maches with monzonite outcrops in area. The chip rock geochemical data shows highest values in west of halakabad mine for Cu and Zn respectively 500 and 900 ppm. These data represents that all samples collected from surficial areas of east of area contain lower concentrations of Copper while sulfide mineralization is more than the other parts. Presence of favorable alteration system in region, presence of monzonite subvolcanic intrusions and regional geological criteria indicates a possible Cu-Au porphyry system in Halakabad area.
{"title":"کانی سازی و اکتشافات ژئوشیمیایی در کمربند ولکانیکی- پلوتونیکی هلاک آباد (جنوب سبزوار) با نگرشی بر اکتشاف مس پورفیری","authors":"محدثه پناهی شهری, محمدحسن کریم پور, فاطمه شبانی","doi":"10.22067/econg.v2i1.3676","DOIUrl":"https://doi.org/10.22067/econg.v2i1.3676","url":null,"abstract":"The investigated area is located 30 Km south of Sabzevar in Halakabad village. Geological phenomenons in area follow a trend of NW-SE. Mineralization consists of metallic and non-metallic (kaolin) mineralization. Disseminated and veinlet mineralization is generally associated with argillic alteration type. Pyrite is the most widespread type of sulfide mineralization in Halakabad occurrences. It usually displays a euhedral habit and have occurred at least in two generations. Calcopyrite is common in veinlets although in minor amounts. Secondary sulfuric acid weathering of the ore has generated huge surficial amounts of oxide and sulfate minerals which of hematite and jarosite are the most abundant. Geochemical exploration was conducted over both drainage geochemistry and rock geochemistry. Results show that some of the stream sediments have higher concentrations of Copper and Zinc than normal. This anomalies maches with monzonite outcrops in area. The chip rock geochemical data shows highest values in west of halakabad mine for Cu and Zn respectively 500 and 900 ppm. These data represents that all samples collected from surficial areas of east of area contain lower concentrations of Copper while sulfide mineralization is more than the other parts. Presence of favorable alteration system in region, presence of monzonite subvolcanic intrusions and regional geological criteria indicates a possible Cu-Au porphyry system in Halakabad area.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"2 1","pages":"21-37"},"PeriodicalIF":0.0,"publicationDate":"2010-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68564792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-30DOI: 10.22067/ECONG.V1I1.3678
A. M. Shafaroudi, M. Karimpour, M. Shahri
Maherabad prospect area, which is studied in detail, is the first porphyry Cu-Au mineralization in the east of Iran. Based on relation of mineralization with subvolcanic intrusive bodies mostly monzonitic with porphyry texture, extent and types of alteration including potassic, sericitic- potassic, quartz- sericite- carbonate- pyrite, quartz- carbonate- pyrite, silicification- propylitic, propylitic, stockwork mineralization, assemblages hypogene mineralization including pyrite, chalcopyrite, bornite and magnetite and high anomalies of Cu and Au, Mineralization is porphyry Cu-Au-type. MA-I area, which is covered by regolith from its surrounding is the most important section of mineralization in the region because of intensive of quartz-sericite-carbonate-pyrite alteration and very high dense quartz-sulfide veinlets. IP/RS and ground magnetic surveys were conducted in the MA-I prospect area and its surrounding plain. Drilling on the IP suede section anomaly resulted to the recognition of sulfide mineralization in on extensive area under the regolith. Surface and underground detailed studies of geology, alteration, mineralization and geochemistry confirm the extension of covered mineralization to the south and west of the area. Based on the ground magnetic anomaly, the center of mineralization system, potassic zone, to the southwest of the area was recognized. Quartz0sericite-carbonate-pyrite alteration zone, which is located around the potassic zone, has very low magnetic response. IP/RS and ground magnetic surveys in a broader area than before are strongly recommended.
{"title":"MINERALIZATION AND GEOPHYSICAL EXPLORATION BY IPIRS AND GROUND MAGNETIC SURVEY IN MA-I AND SURROUNDING AREA, MAHERABAD PORPHYRY CU-AU PROSPECT AREA, EAST OF IRAN","authors":"A. M. Shafaroudi, M. Karimpour, M. Shahri","doi":"10.22067/ECONG.V1I1.3678","DOIUrl":"https://doi.org/10.22067/ECONG.V1I1.3678","url":null,"abstract":"Maherabad prospect area, which is studied in detail, is the first porphyry Cu-Au mineralization in the east of Iran. Based on relation of mineralization with subvolcanic intrusive bodies mostly monzonitic with porphyry texture, extent and types of alteration including potassic, sericitic- potassic, quartz- sericite- carbonate- pyrite, quartz- carbonate- pyrite, silicification- propylitic, propylitic, stockwork mineralization, assemblages hypogene mineralization including pyrite, chalcopyrite, bornite and magnetite and high anomalies of Cu and Au, Mineralization is porphyry Cu-Au-type. MA-I area, which is covered by regolith from its surrounding is the most important section of mineralization in the region because of intensive of quartz-sericite-carbonate-pyrite alteration and very high dense quartz-sulfide veinlets. IP/RS and ground magnetic surveys were conducted in the MA-I prospect area and its surrounding plain. Drilling on the IP suede section anomaly resulted to the recognition of sulfide mineralization in on extensive area under the regolith. Surface and underground detailed studies of geology, alteration, mineralization and geochemistry confirm the extension of covered mineralization to the south and west of the area. Based on the ground magnetic anomaly, the center of mineralization system, potassic zone, to the southwest of the area was recognized. Quartz0sericite-carbonate-pyrite alteration zone, which is located around the potassic zone, has very low magnetic response. IP/RS and ground magnetic surveys in a broader area than before are strongly recommended.","PeriodicalId":37178,"journal":{"name":"Journal of Economic Geology","volume":"1 1","pages":"1-17"},"PeriodicalIF":0.0,"publicationDate":"2010-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68564710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}