Mineralization style of the Randu Kuning porphyry Cu-Au and intermediate sulphidation epithermal Au-base metals deposits at Selogiri area, Central Java Indonesia

2020 ◽  
Author(s):  
Sutarto ◽  
Arifudin Idrus ◽  
Agung Harjoko ◽  
Lucas Donny Setijadji ◽  
Franz Michael Meyer ◽  
...  
Keyword(s):  
Base Metals ◽  
Porphyry Cu ◽  
Central Java ◽  
Epithermal Au

scholarly journals Hydrothermal Alteration and Mineralization of the Randu Kuning Porphyry Cu-Au and Intermediate Sulphidation Epithermal Au-Base Metals Deposits in Selogiri, Central Java, Indonesia

2016 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Sutarto Sutarto ◽  
Arifudin Idrus ◽  
Agung Harijoko ◽  
Lucas Donny Setijadji ◽  
Franz Michael Meyer ◽  
...  
Keyword(s):  
Hydrothermal Alteration ◽  
Carbonate Rocks ◽  
Base Metals ◽  
Porphyry Cu ◽  
Central Java ◽  
Copper Gold ◽  
Volcaniclastic Rocks ◽  
Gold Grade ◽  
Epithermal Au ◽  
Yogyakarta City

The Randu Kuning Porphyry Cu-Au prospect area is situated in the Selogiri district, Wonogiri regency, Central Java, Indonesia, about 40 km to the South-East from Solo city, or approximately 70 km east of Yogyakarta city. The Randu Kuning area and its vicinity is a part of the East Java Southern Mountain Zone, mostly occupied by both plutonic and volcanic igneous rocks, volcaniclastic, silisiclastic and carbonate rocks. Magmatism-volcanism products were indicated by the abundant of igneous and volcaniclastic rocks of Mandalika and Semilir Formation. The Alteration zones distribution are generally controlled by the NE–SW and NW–SE trending structures. At least eight types of hydrothermal alteration at the Randu Kuning area and its vicinity had been identified, i.e. magnetite + biotite ± K-feldspar ± chlorite (potassic), chlorite + sericite + magnetite ± actinolite, chlorite + magnetite ± actinolite ± carbonate (inner propylitic), chlorite + epidote ± carbonate (outer propylitic), sericite + quartz + pyrite (phyllic), illite + kaolinite ± smectite (intermediate argillic), illite + kaolinite ± pyrophyllite ± alunite (advanced argillic) and quatz + chlorite (sillisic) zones. The Randu Kuning mineralization at Selogiri is co existing with the porphyry Cu-Au and intermediate sulphidation epithermal Au-base metals. Mineralization in the porphyry environment is mostly associated with the present of quartz-sulphides veins including AB, C, carbonate-sulphides veins (D vein) as well as disseminated sulphides. While in the epithermal prospect, mineralization is particularly associated with pyrite + sphalerite + chalcopyrite + carbonate ± galena veins as well as hydrothermal breccias. The Randu Kuning porphyry prospect has copper gold grade in range at about 0.66–5.7 gr/t Au and 0.04–1.24 % Cu, whereas in the intermediate sulphidation epithermal contain around 0.1–20.8 gr/t Au, 1.2–28.1 gr/t Ag, 0.05–0.9 % Zn, 0.14–0.59 % Pb and 0.01–0.65 % Cu.

scholarly journals VEINS AND HYDROTHERMAL BRECCIAS OF THE RANDU KUNING PORPHYRY Cu-Au AND EPITHERMAL Au DEPOSITS AT SELOGIRI AREA, CENTRAL JAVA INDONESIA

2015 ◽  
Vol 7 (2) ◽  
pp. 82 ◽  
Author(s):  
Sutarto Sutarto ◽  
Arifudin Idrus ◽  
Agung Harijoko ◽  
Lucas Donny Setijadji ◽  
Franz Michael Meyer
Keyword(s):  
Wall Rock ◽  
Research Area ◽  
Quartz Diorite ◽  
Base Metals ◽  
Rock Fragments ◽  
Quartz Veins ◽  
Porphyry Cu ◽  
Central Java ◽  
Volcanic Glasses ◽  
Epithermal Au

The Randu Kuning prospect is situated at Selogiri area, Wonogiri, Central Java, Indonesia. This location is about 40 km to the south-east from Solo city or approximately 70 km east of Yogyakarta city. Many Tertiary dioritic rocks related alterationmineralisation were found at the Randu Kuning area and its vicinity, including hornblende microdiorite, hornblende-pyroxene diorite and quartz diorite. Mineralisation type of the Randu Kuning prospect was interpreted as porphyry Cu-Au and a number epithermal Au-base metals deposits in its surrounding. The closed existing of porphyry Cu-Au and epithermal Au-base metals type deposits at the Randu Kuning area produced a very complex of veins and hydrothermal breccias crosscutting relationship. A lot of porphyry veins types were found and observed at the Randu Kuning area, and classified into at least seven types. Most of the porphyry veins were cross cut by epithermal type veins. Many epithermal veins also are found and crosscut into deeply porphyry vein types. There are genetically at least two type of hydrothermal breccias have recognized in the research area, i.e. magmatic-hydrothermal breccia and phreatomagmatic breccia. Magmatic hydrothermal breccias are mostly occured in contact between hornblende microdiorite or quartz diorite and hornblende-pyroxene diorite, characterized by angular fragments/clasts supported or infilled by silicas, carbonates and sulphides matrix derived from hydrothermal fluids precipitation. Phreatomagmatic breccias are characterized by abundant of the juvenile clasts, indicated contact between hot magma with fluid or water as well as many wall rock fragments such as altered diorites and volcaniclastic rock clasts set in clastical matrix. The juvenile clasts usually compossed by volcanic glasses and aphanitic rocks in rounded-irregular shape. Both veining and brecciation processes have an important role in gold and copper mineralisation of the Randu Kuning Porphyry Cu-Au and epithermal Au-base metals deposits, mostly related to the presence of quartz veins/veinlets containing significant sulphides, i.e., quartz with thin centre line sulphides (Abtype) veins, pyrite±chalcopyrite (C type) veinlets, pyrite+quartz± chalcopyrire±carbonate (D type) veins of porphyry types as well as epithermal environment quarts+ sulphides+carbonate veins.

Asynchronous formation of the adjacent epithermal Au-Cu and porphyry Cu-Mo deposits in the Zijinshan orefield, southeast China

2018 ◽  
Vol 102 ◽  
pp. 351-367 ◽  
Author(s):  
Wenting Huang ◽  
Huaying Liang ◽  
Lei Wu ◽  
Jing Wu ◽  
Jing Li ◽  
...  
Keyword(s):  
Southeast China ◽  
Porphyry Cu ◽  
Epithermal Au

scholarly journals Paleozoic Epithermal Au and Porphyry Cu Deposits in North Xinjiang, China: Epochs, Features, Tectonic Linkage and Exploration Significance

2002 ◽  
Vol 52 (4) ◽  
pp. 291-300 ◽  
Author(s):  
Kezhang Qin ◽  
Shu Sun ◽  
Jiliang Li ◽  
Tonghui Fang ◽  
Shulai Wang ◽  
...  
Keyword(s):  
Porphyry Cu ◽  
North Xinjiang ◽  
Epithermal Au

Cenozoic Strike-Slip Tectonics and Structural Controls of Porphyry Cu-Mo and Epithermal Deposits During Geodynamic Evolution of the Southernmost Lesser Caucasus, Tethyan Metallogenic Belt

2019 ◽  
Vol 114 (7) ◽  
pp. 1301-1337 ◽  
Author(s):  
Samvel Hovakimyan ◽  
Robert Moritz ◽  
Rodrik Tayan ◽  
Rafael Melkonyan ◽  
Marianna Harutyunyan
Keyword(s):  
Base Metal ◽  
Strike Slip ◽  
Early Miocene ◽  
Tectonic Plate ◽  
Porphyry Cu ◽  
Metallogenic Belt ◽  
Late Neogene ◽  
Lesser Caucasus ◽  
Dextral Strike Slip ◽  
Epithermal Au

Abstract The Zangezur-Ordubad mining district of the southernmost Lesser Caucasus is located in the central segment of the Tethyan metallogenic belt and consists of porphyry Cu-Mo and epithermal Au and base metal systems hosted by the composite Cenozoic Meghri-Ordubad pluton. Ore-hosting structures and magmatic intrusions are predominantly confined to a central N-S–oriented corridor 40 km long and 10 to 12 km wide, located between two regional NNW-oriented right-lateral faults, the Khustup-Giratagh and Salvard-Ordubad faults. The anatomy and kinematics of the main fault network are consistent with dextral strike-slip tectonics controlled by the NNW-oriented Khustup-Giratagh and Salvard-Ordubad faults. Dextral strike-slip tectonics was initiated during the Eocene, concomitantly with final subduction of the Neotethys, and controlled the emplacement of the Agarak, Hanqasar, Aygedzor, and Dastakert porphyry Cu-Mo and Tey-Lichkvaz and Terterasar epithermal Au and base metal deposits. The Eocene structures were repeatedly reactivated during subsequent Neogene evolution in transition to a postsubduction geodynamic setting. Ore-bearing structures at the Oligocene world-class Kadjaran porphyry Cu-Mo deposit were also controlled by dextral strike-slip tectonics, as well as porphyry mineralization and its epithermal overprint hosted by an early Miocene intrusion at Lichk. Eocene to early Miocene dextral strike-slip tectonics took place during NE- to NNE-oriented compression related to Paleogene Eurasia-Arabia convergence and subsequent Neogene postcollision evolution. Paleostress reconstruction indicates major reorganization of tectonic plate kinematics since the early Miocene, resulting in N-S– to NW-oriented compression. Early Miocene epithermal overprint at the Kadjaran porphyry deposit and left-lateral reactivation of faults and mineralized structures are linked to this late Neogene tectonic plate reorganization.

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