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By Miguel Carrera, Martín Bradshaw, Víctor Araya

Teck Resources Limited está implementando desde hace ya algunos años un fuerte programa global de incorporación tecnológica, tanto de desarrollo propio como también de empresas líderes en tecnología minera. Es así como la operación Teck Carmen de Andacollo ha implementado un revolucionario sistema desarrollado por la empresa MineSense Technologies Ltd, que permite mejorar considerablemente la selectividad de los equipos de carguío en las frentes de bancos, reduciendo la cantidad de mineral perdido en botaderos y eliminando el estéril que diluye el mineral destinado al procesamiento.

Sep 30, 2022

By Jorge Da Silva

El presente trabajo señala la importancia de la función del área de Tecnologías de la Información en el logro de los objetivos de la empresa minera Yanacocha a través de un programa de excelencia operacional, donde se optimiza y distribuye de mejor manera los recursos de la empresa, se explora nuevas áreas, se legaliza los permisos correspondientes para acceder a nuevas tierras y se compromete a los trabajadores con los objetivos de la corporación.

Sep 9, 2007

By Peter C. Badgley

Three tectonic provinces within the Cordilleran System, are analyzed in terms of tectonic framework. (1) Precambrian terrain of North-Central Colorado; (2) The Pacific Northwest; and (3) The San Andreas-Garlock fault system and associated features. In each case a close relation- ship is seen to exist between: (I) Arcuate mountain development; (2) Precambrian basement fabric; (3) Major fault patterns; and (4) Major mineral occurrences. The arcuate trends developed when the basement was still mobile. Later competent deformation rejuvenated pre-existing lines of weakness. Because of the pre-existing arcuate framework, the rejuvenated faults frequently act as conjugate shears (strike-slip faults) flanking the old arcs. The conjugate shears intersect to form wedge- shaped plates. When such plates move forward along boundary strike-slip faults in response to post basement orogenic forces, new secondary fracture systems are generated in the country rock flanking the advancing wedge. The apex regions of the wedges are particularly favorable for detailed exploration.

Jan 1, 1959

By R Hall

Subduction zone magmatism is a direct response to tectonic and chemical processes operating at convergent margins. Changes in the tectonic configuration of plate boundaries in SE Asia during the Cenozoic had consequences for the nature and volume of magma produced. Retreat or advance of the trench hinge has probably been an important process in controlling the presence or absence of magmatism in SE Asian subduction zones. This process also provides a means of replenishing the mantle wedge and counteracting the effects of melt extraction in depleting the wedge. Changes in the nature of recycled material and lithologies of the over-riding plate also have the potential to influence the lavas that are erupted in arcs. Several locations in SE Asia have experienced magmatism bearing the geochemical signature of subduction but are remote from coeval subduction zones. Such magmatism requires an earlier period of mantle enrichment by subduction but may result from localised extension. The distribution of such magmatism may provide information of tectonic value. Some adakitic magmatism occurred in tectonic settings where there is no evidence for subduction of young oceanic crust at the time of magma genesis. Slab melting in such settings is not possible and alternative mechanisms are required to explain the occurrence of, at least some, adakitic lavas.

Jan 1, 1999

By Green P. F

Apatite Fission Track Analysis (AFTA) is a thermal history reconstruction tool that enables determination of magnitude and timing of maximum paleotemperature and paleo-geothermal gradient at the time of maximum paleotemperatures. From this information, the amount of section missing at major unconfornities can be estimated and incorporated into basin models. The Gippsland Basin has a number of distinct problems that can be tackled using AFTA. 1. The nature of the regional break between the Late Cretaceous-Tertiary Latrobe Group and the underlying Early Cretaceous Strzelecki Group. 2. The tectonic history of the basement flanking the basin and its effect on sediment composition. 3. The age of igneous activity in the basin, as typified by the widespread basaltic plugs and dykes intruding the outcropping Strzelecki Group. Major uplift and erosion within, and adjacent to, the early Cretaceous rift basin in the Mid-Cretaceous, at -95 to 100 Ma, initially constrained the Latrobe Group depositional area to the central deep of the Gippsland Basin and provided an elevated source of quartz-rich detritus for the Latrobe Group reservoirs. This is in marked contrast to the preceding period in the early Cretaceous when contemporaneous volcanism dominated as a source of detritus, producing quartz-poor lithic sandstones, in which a host of attendant diagenetic reactions destroyed their reservoir potential. Initial uplift and erosion of the volcanogenic Strzelecki Group also occurred in the mid-Cretaceous as revealed by a number of distinct inversion structures, and erosion of this material will have locally provided very poor quality sand to the basal Latrobe Group.

Jan 1, 1992

By M. S. Riyaz Ulla

The Hutti Greenstone belt, located in the northern side of Dharwar Craton, India, contains several promising gold fields. It is predominantly composed of meta-volcanics with minor intercalations of meta-sedimentaries. Alkali-SiO2 and Zr-P2O5 diagrams, immobile element trends, and an iron-rich trend on the AFM diagram indicate that the volcanic suite is low-potassium tholeiitic basalt. The lower Mg number, MgO-TiO2, MgO-Ni, and Ni-Zr plots reveal that the basalt was derived from a fractionated, highly evolved magma generated by 10-20% melting of the mantle at 1100°C and 5 kb pressure. The chemical variations suggest that the Hutti metabasalt represents volcanic arc rocks generated at a converging plate margin.

Jan 1, 1993

By M J. Andrews, P J. White, I Bogie

Active geothermal systems occur widely in Sumatra and in the Taupo Volcanic Zone (TVZ) ofNew Zealand. There are also many occurrences of epithermal gold mineralisation in Sumatra, some of which are economic. Minor sub-economic occurrences of gold have been reported in the TVZ but none have yet been mined. There are both similarities and differences in the nature of the active geothermal systems and mineral deposits in Sumatra and New Zealand, which can be systematically related to the tectonic setting. The thicker crust and consequent predominance of silicic volcanism in New Zealand leads to hydrothermal systems which are little eroded and with limited lateral outflows. The systems in Sumatra are of mixed character, with some of the characteristics of those in andesitic island arcs such as Java or the Philippines, e.g. a higher proportion of systems with identifiable acid magmatic volatiles, a greater potential for deep erosion and lateral outflows than in New Zealand; but modified by the more oblique component of subduction and thickened crust so that some are localised in volcano-tectonic depressions and consequently have high piezometric levels of primary hydrothermal fluid. The unusual occurrence of calcic zeolites in veins associated with gold mineralisation in Sumatra is thought to be indicative of æsatelliteÆ boiling zones along de-gassed hydrothermal outflows.

Jan 1, 1995

By Bogie I, White P. J

Active geothermal systems occur widely in Sumatra and in the Taupo Volcanic Zone (TVZ) of New Zealand. There are also many occurrences of epithermal gold mineralisation in Sumatra, some of which are economic. Minor sub-economic occurrences of gold have been reported in the TVZ but none have yet been mined. There are both similarities and differences in the nature of the active geothermal systems and mineral deposits in Sumatra and New Zealand, which can be systematically related to the tectonic setting. The thicker crust and consequent predominance of silicic volcanism in New Zealand leads to hydrothermal. systems which are little eroded and with limited lateral outflows. The systems in Sumatra are of mixed character, with some of the characteristics of those in andesitic island arcs such as Java or the Philippines, eg a higher proportion of systems with identifiable acid magmatic volatiles, a greater potential for deep erosion and lateral outflows than in New Zealand; but modified by the more oblique component of subduction and thickened crust so that some are localised in volcano-tectonic depressions and consequently have high piezometric levels of primary hydrothermal fluid. The unusual occurrence of calcic zeolites in veins associated with gold mineralisation in Sumatra is thought to be indicative of "satellite" boiling zones along de-gassed hydrothermal outflows.

Jan 1, 1995

By John C. Osmond

One of the least known geologic regions in the U.S. is the area now called the Basin and Range Province. It is paradoxical that so little geologic information has been compiled for a province that has yielded billions of dollars worth of metals and is currently producing a small amount of oil. Regional stratigraphic studies of parts of this large territory have been published only recently, and regional structural interpretations of even parts of the province are rare in the literature. This, of course, does great injustice to the earliest workers: Gilbert, Russell, Le Conte, Spur, Louderback, and others, who recognized the area as distinctively different from the rest of North America. Their simplified picture of the structure of the ranges and the province as a whole is the groundwork for present understanding and has never been superseded. Since their early works, however, geologic data from the province has consisted largely of detailed reports of widely scattered mining districts. Each district has been described as though it were an island in an unknown sea.

Jan 3, 1960

The coal basins that formed near the margin of Permian Australia were comparable in size with the Appalachian coalfields and with the European fields between Wales and Poland. They formed on the foreland side of a growing orogen in a system of linked transform basins formed by transtension on strike-slip faults. They were terminated and compressed when the Gympie volcanic arc was accreted to the orogen. Another huge system of Permian coal basins extending far inland from the Permian coast was also terminated when the Gympie Terrane was Accreted.

Jan 1, 1987

Mineral deposits of the central New Guinea region (Gunung Bijih, Ok Tedi, Mount Kare, Porgera, Frieda River) and of southeastern New Guinea (Wau-Edie Creek, Wafi, Hamata, Hidden Valley, Tolukuma, Misima) are associated with hot, forceful intrusions of magma of mantle origin that penetrated thick Precambrian and Palaeozoic continental crust. The interaction of high- temperature melt with continental crust, and the differentiation of melt while in transit through thick crust, may be factors in generating ore. Mineralised intrusives in central New Guinea are a result of Neogene- Quaternary magmatism and were emplaced in a foreland thrust belt environment, a setting similar to the (mineralised) Laramide intrusions of southwestern USA. In both cases, central New Guinea and the Laramide, magmatism is not obviously subduction- related. Mineralised intrusives in south- eastern New Guinea (Wau-Edie Creek, etc.), also, are in a thrust belt setting, and are not obviously subduction-related. The association of. gold in southeastern New Guinea with a second (Pliocene) phase of igneous activity, rather than with earlier (Miocene) activity suggests that re-working by successive intrusions may be a factor in localising ore. This is seen, also, in the Bismarck-Solomon islands region where the richer deposits are associated with later (Pliocene) intrusives rather than with earlier (Eocene-Oligocene) intrusives. Unlike the mainland mineral deposits, those of the Bismarck-Solomon islands are clearly subduction-related.

Jan 1, 1991

Five types of mineral resource were known in the sedimentary cover of the oceans and seas floors prior to the 1980s: 1. hydrocarbon fields including some very large zones of oil and gas accumulation; 2. æRed SeaÆ type thermal oozes with increased concentrations of noble metals; 3. ferromanganese nodules; 4. concentrations of metallic sulphides (æBlack SmokersÆ); and 5. cobalt-bearing ferromanganese crusts on the summits and slopes of seamounts.   Since then, the so called æWhite SmokersÆ, containing sulphides of copper and zinc, have been discovered. The ore horizons (manganese, copper, nickel and other metals) of the sedimentary cover of deep-sea basins comprise a sixth type of mineral resource in the oceans. These horizons have not only a theoretical, but also a principal economic significance.

Jan 1, 1995

Five types of mineral resource were known in the sedimentary cover of the oceans and seas floors prior to the 1980's :1) hydrocarbon fields including some very large zones of oil and gas accumulation; 2) "Red Sea" type thermal oozes with increased concentrations of noble metals; 3) ferromanganese nodules; 4) concentrations of metallic sulphides ("Black Smokers"); and 5) cobalt-bearing ferromanganese crusts on the summits and slopes of seamounts. Since then, the so called "White Smokers", containing sulphides of copper and zinc, have been discovered. The ore horizons (manganese, copper, nickel and other metals) of the sedimentary cover of deep-sea basins comprise a sixth type of mineral resource in the oceans. These horizons have not only a theoretical, but also a principal economic significance

Jan 1, 1995

By Peter W. Lipman

In the Rocky Mountain region, variations in Tertiary mineralization correlate with changes in tectonic setting and associated igneous activity that can largely be related to tectonics along the west boundary of the American plate. Successive settings include compressional tectonics and associated continental-arc igneous activity; transitional igneous types associated with intra- and back-arc extension; and basaltic or bimodal basalt-rhyolite assemblages associated with Basin and Range extension in- ward of a growing transform boundary between Pacific and American plates.

Jan 1, 2013

"The sulphide nickel resources of Australia are concentrated in the Western Australian Shield. This shield is considered to have developed by extensive, but incomplete, Proterozoic reworking of once-continuous Archaean crust. It now constitutes relic Archaean cratons and intervening orogenic mobile belts transected by narrow, curvilinear tectono-thermal mobile belts of younger Proterozoic age. Remnants of the Archaean cratons are exposed in the Yilgarn and Pilbara Blocks. In the former an ancient (to ca 3600 m.y.) high-grade gneiss terrain (Western Gneiss Terrain) occurs along the western margin of the block and is interpreted to flank younger (ca3000-2800 m.y.) greenstone belts to the east. Ancient (to ca3500 m.y.) granitoid-greenstone terrains dominate the Pilbara Block.Proterozoic mobile belts contain only traces of nickel mineralization, except for one locality in the Halls Creek Province. The Archaean high-grade gneiss terrains contain no important mineralization, and the Pilbara granitoid-greenstone terrains contain only scattered examples of less important types of mineralization.The important deposits (e.g. Kambalda, Windarra, Agnew, Mt Keith) are all of komatiitic affinity and are best developed in the youngest greenstone belts of the eastern part of the Yilgarn Block. In particular, they are concentrated within, and adjacent to, the Norseman-Wiluna Belt, which contrasts in age, lithofacies and structural style with all other greenstone belts in the shield. It is interpreted to have been a rift zone. Within this belt the two main deposit types—the volcanic peridotite-associated and intrusive dunite-associated deposits—are concentrated into spatially separate zones. Precise controls on this heterogeneous distribution cannot be determined unequivocally from available data. One possibility is that the major volcanic peridotite-associated deposits were developed selectively in the actively subsiding axial part of the rift zone during the early extensional phase, whereas intrusive dunite-associated deposits were formed during a subsequent (less active?) stage of volcanic basin development. Distinctive sub-types (facies) of the volcanic peridotite-associated deposits form clusters that are generally within the rift zone. These may represent deposits related to discrete eruption centres, and at least part of their variation is due to relative position within extensive, topographically confined, linear flows."

Jan 1, 1984

By Boorder De, B. S. Panov, A. B. Westerhof, V. A. Korcemagin

Paper presented at the conference on Economic geology in Europe and beyond II, models for <mineral deposits> in sedimentary <basins>, held in Keyworth, UK, 13-14 April 1994. The Hg and Sb deposits of the Mediterranean and Circum-Pacific Belts are often found at elevated structural levels, suggesting that their preferential occurrence in young orogenic belts is not a fundamental metallogenic feature but merely reflects their chances of surviving post-orogenic peneplanation. In western Europe their emplacement appears often to be related to late orogenic extensional events accompanied by a notable increase in heat flow. Although Nikitovka and Almaden have quite different settings, both appear to be related to deep-reaching shears. Together with brittle fault zones at higher levels, these provided pathways for fluid phases that originated at least partially within the mantle. The Nikitovka deposits are located in the Donets segment of the 2 000 km Pripyat-Dniepr-Donets palaeorift in the East European Platform. Initiated in the mid-Devonian with a possible Precambrian precursor, its listric boundary faults displace the Moho from a depth of about 50 km north and south of the rift to 35 km along the axes of the Pripyat and Dniepr segments. The steep central anticline of the Donets segment, within which the main Hg-Sb district is located, is interpreted to be associated with a reactivated fault reaching into the upper mantle. The Almaden syncline, formed during the Variscan Orogeny, may be an older pull-apart basin or half-graben associated with the collapse of the Cadomian Orogenic Belt. It is situated on a major ENE-WSW-striking shear zone which may represent a Late Cadomian transfer zone reaching into the mantle

Apr 1, 1995

By D Craw, P Upton

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Otago Schist belt of southern New Zealand hosts widespread orogenic gold deposits. Erosion of these orogenic gold deposits has led to the formation of numerous placer deposits distributed across and beyond the host schist belt. Numerical modelling of crustal scale deformation and geomorphic evolution has defined the key tectonic features that have controlled the severance of detrital gold deposits from their sources. Tectonic activity over the past 20 million years, during development of the modern Pacific-Australian plate boundary, has severed links between some placers and their sources. Detrital gold was transported south from the Otago Schist source region in two different river systems in the Miocene. Mesozoic orogenic gold deposits shed gold into rivers that flowed to the south. These rivers were terminated by the rise of north-west-trending basement ridges at the boundary between weak schist crust and strong greywacke crust, and the ridges were controlled by pre-existing faults at that rheological boundary. In contrast, rising mountains close to the developing plate boundary in the Miocene were the locus of new orogenic gold deposits hosted in extensional faults. These gold deposits were rapidly exhumed and contributed detrital gold to orogen-parallel Miocene rivers that flowed to the south-west. Pleistocene deformation on mainly north-west and north-east orientations, and associated river capture, has severed the links between these Miocene orogenic deposits and downstream detrital gold.CITATION:Craw, D and Upton, P, 2015. Tectonic severance of links between placer gold and its sources, southern New Zealand , in Proceedings PACRIM 2015 Congress, pp 541–544 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Chen Lin

Tectonic stress is an important parameter for understanding the dynamics of underground engineering and for the exploitation of coalbed methane. Multiple-period structural features usually have complex spatial relationships in tectonic superposition areas, which provides evidence for identification of the sequence of the tectonic stress period. Conjugated joints and slickensides are used to reconstruct the tectonic stress of the No. 8 Mine in Pingdingshan. Based on the geological unit division and field measurements, data on hundreds of joints and slickensides are collected from 33 stations. The tectonic stress results indicated by the conjugated joints show that there are mainly four directions of tectonic stress: NEE-SWW, NW-SE, NE-SW, and NNESSW. The tectonic stress results of the slickensides indicate that there are mainly four directions of tectonic stress: NNE-SSW, NNW-SSE, NEE-SWW, and NW-SE. According to the systematic analysis of the joints and slickensides, this paper separates the superposed joint and slickenside sets and identifies the tectonic stress periods with their abutting relationships. Three tectonic stress periods are determined and the sequence of the tectonic stress periods is NE-SW, NW-SE, and NEE-SWW. The results are consistent with other tectonic stress measurements for both the region and the locality.

Four data sets are required to put constraints on the tectonic evolution of the southern rim of the Pacific Ocean basinI . data bearing on the dispersal of the major Gondwanaland continental fragments and the birth of the Southern Ocean,2. data bearing on the interaction of the Pacific Ocean basin lithosphere with the South American, Antarctic, and Australasian continental masses,3. data bearing on.the evolution of the Scotia Sea floor, and 4. data bearing on the evolution of the various continents, microcontinents. and volcanic arcs.

Jan 1, 1990

By Luis Ayala, Francisco Solano

Entre Huachón y Corralcancha (Cordillera Oriental) se ha identificado un corredor estructural NO-SE (Chaska-Rumichaca) ubicado a ~30km al este de Cerro de Pasco. Cuyos límites son fallas regionales que determinan un bloque paleozoico del Complejo Metamórfico del Marañón (CMM). El límite occidental (Falla Rumichaca) corresponde a una falla inversa de vergencia SO que aflora dentro del CMM; mientras que el límite oriental (Falla Chaska) es una zona de cizalla compresional de vergencia NE que coloca al CMM sobre los Grupos Mitu (Pérmico superior-Triásico inferior) y Pucará (Triásico superior-Jurásico inferior) replegados. Este límite exhibe un flexionamiento de NO-SE a N-S que está asociado a fallas subordinadas de cinemática compresional, extensional y de desgarre.

May 1, 2008