Supergene leaching, oxidation, and chalcocite enrichment in porphyry and related Cu deposits take place in the weathering environment to depths of several hundred meters. The fundamental chemical principles of su-pergene processes were elucidated during the early decades of the twentieth century, mainly from studies in the western …

The occurrence of supergene Au mobility in the surficial zone of orogenic gold deposits in the Otago Schist has been widely acknowledged for over 100 years (Finlayson 1908; Park 1908; Williams 1974; Craw & MacKenzie 1992 ). Similar processes have also affected many placer gold deposits to varying extents (Craw & Youngson …

In all cases of supergene enrichment traces of the chert bands are visible and the dissolution or replacement processes for the removal of quartz are clear, in direct contrast to the most important deep saprolite ore deposits that show no trace of chert bands.The widespread acceptance of an inappropriate and untenable supergene enrichment model ...

Supergene mineralization is controlled by the parent rock composition, climatic conditions, geomorphological environment, and chemical compounds added during mineral processing. They appear in alteration zones called "orecretes.". Bronze Age miners exploited these easily accessible high-grade soft ores for Fe, Cu, Pb, and Ag.

Fluid inclusion characteristics and ore-forming fluid evolution of the Tuokuzibayi gold deposit in the southern margin of Altay. Article. Jan 2020. ZHANG Min. NIU XiangLong. MO LingChao. ZHOU QiFeng.

Supergene ore deposits form in regions where weathering is favoured by a humid and hot climate that promotes the profuse growth of vegetation. Vegetation and organic matter affect supergene alteration by two mechanisms. The first is the direct influence of plants on the soil water (e.g. retention).

Main ore forming processes within the deep supergene zone (i.e., the uppermost 180 m below the present surface) were dissolution of dolomite and its local …

The formation of enriched sulfide ore in porphyry systems is broadly dependent upon hypogene ore mineralogy, lithology of host rocks, and character of alteration (Titley & Marozas 1995). Ideal conditions for formation of supergene sulfides are high pyrite– chalcopyrite ratios in hypogene ore hosted in felsic

In ore deposit geology, supergene processes or enrichment are those that occur relatively near the surface as opposed to deep hypogene processes. Supergene processes include the predominance of meteoric water circulation with concomitant oxidation and chemical weathering. The descending meteoric waters oxidize the primary sulfide ore minerals …

The word is used to contrast with hypogene, or genesis at depth. In most cases, supergene ores are formed as a result of action of meteoric waters on rocks through the chemical …

The study of supergene processes (i.e., secondary processes running in ore deposits and driven by thermodynamic nonequilibrium between ore- and rock-forming …

Genesis of high-grade iron ore deposits • Supergene (iron ore) deposit: Mineral deposit or enrichment formed near to or at the surface, commonly by descending groundwater (supergene fluids) • Hypogene (iron ore) deposit: Mineral deposit formed below the surface, usually associated with mostly ascending, "warm"

Abstract. Supergene minerals form under near-ambient conditions on the Earth's surface. Supergene mineralization is controlled by the parent rock composition, …

The Morowali Ni-laterite deposit is located in the East Sulawesi Ophiolite, which is a large ophiolite belt on Sulawesi Island, Indonesia. The Morowali deposit is developed on a laterite profile due to ophiolite weathering, with saprolite, limonite, and ferruginous cap horizons from the bottom to top. Based on the occurrence of garnierite …

Introduction. Supergene copper mineralization (SCM) is produced by the interaction between sulfides and supergene processes and was originally defined by Ransome (1912) as sulfide oxidation and leaching of ore deposits in the weathering environment, and any attendant secondary sulfide enrichment.In order to form …

Mineral deposition in the supergene ore took place under near-neutral to mildly acidic conditions. ... A number of filamentous, coccoidal and rod-shaped morphological microstructures were ...

A critical review of Early Paleozoic W and Cu mineralized and barren granitoids in Southeast China: Magmatic differentiation, oxygen fugacity, and magmatic sources. Zhen-Tao Song, Xi-Sheng Xu, Mei-Fu Zhou, Yan Xia, Ding-Sheng Jiang. Article 104025. View PDF.

The paragenesis of copper oxide mineral formation reflects local, dynamic changes in supergene solution composition attributable to reaction between host-rock mineral components and dissolved species. Especially important are the concentrations of Fe +++ (vs. Fe ++), SO 4 =, H +, and Cu ++ (vs. Cu +). Because mineral assemblages, even …

that suggest the ore formation was due to supergene enrichment (likely coupled with microbial activity). In contrast, several northern ia ores hosted within quartz-sandstone breccias exhibit petrographic relations, mineral morphologies, and REE signatures indicating inorganic precipitation, and a likely hydrothermal origin with supergene

A typical supergene profile of a gold deposit consists of (1) a leached cap, (2) an oxidized zone, (3) a supergene enrichment zone, and (4) the primary ore zone . Free particles of high-purity Au (>99% Au) commonly occur in the former two zones as the result of the refinement of Au and the removal of Ag and other metals from Au–Ag alloys and ...

THE EVOLUTION OF SUPERGENE ENRICHMENT IN THE MORENCI PORPHYRY COPPER DEPOSIT, GREENLEE COUNTY, ARIZONA by Merritt Stephen Enders _____ A Dissertation Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the …

The significant difference between these ores and the supergene mimetic martite-goethite ores is that they grow downward, with the total destruction of any of the …

rod mill work indexes was much more significant and indicated that . some of the primary ore and a greater amount of the supergene ore is . less competent than the average. Hence a reasonably high ...

The ore body length, width, thickness, and dip angle are 4000 to 4400 m, 1700 to 3000 m, 6 to 50 m, and 5 to 30°, respectively. It is a very large nickel deposit with a nickel resource of 4 million tons. ... Indonesia: implications for the lateritization process and Ni supergene enrichment in the tropical rainforest. J Asian Earth Sci 93: 74–88.

During this program a resource of more than 20 million metric tons (Mt) Cu was discovered, including 6 Mt Cu of oxide, mixed and secondary sulfide ore, representing one of the largest supergene copper resources …

In the traditional view, supergene ore and gangue minerals are the products of reactions between hypogene sulfide minerals and descending, acidic meteoric waters; these …

Mineralogical and textural characteristics of the studied rocks indicate that copper and vanadium minerals in the Araba Formation are related to supergene processes and telodiagenesis after oxidation of sulfides and dissolution of feldspar grains and carbonate cement in the clastic rocks most probably during the Upper Devonian-Lower ...

The supergene routes of laterite formation predominantly involve periodic meteoric water circulation derived from precipitation of snow and rain. The meteoric waters flow in the …

Most workers in the field of iron ore equate the term 'supergene iron ore' with lateritic iron ore. Both these ore types are supergene but their end products are vastly different. Broadly the term supergene means genesis from above, in contrast to hypogene, meaning genesis from below which by implication is related to hydrothermal processes.

limestone. An unusual form of very high-grade low-phosphorous hematite ore (64–68 wt% Fe, <0.03 wt% P) consisting of martite and ochreous hematite at Ferro Gully near. Newman in Western ...