Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке

Издание:2012 г., 9 стр., УДК: 553.411'43.075 (041)(571.62)
Язык(и)Русский
Малмыж - новая крупная золото-меднопорфировая система мирового класса в Сихоте-Алине (Хабаровский Край, Дальний Восток России)

Малмыжская золото-меднопорфировая система (далее «Малмыж») была выявлена в 2005-2007 гг горнодобывающей компанией Phelps Dodge Corporation (США) на основе
анализа геологических отчетов советских и российских геологов и в результате проведенных затем полевых работ. Эта компания, являвшаяся в то время одним из крупнейших производителей меди в мире, через учрежденные ею российские дочерние предприятия проводила на Дальнем Востоке России поиски крупных золотомеднопорфировых и собственно золоторудных месторождений. Общее руководство работами осуществляли региональный менеджер по развитию новых проектов Мак Кэнби (Mac Canby) и главный геолог российского филиала компании А.Б. Волков. В 2008 компания, а с нею и Малмыжский проект, были приобретены компанией Freeport-McMoRanCopper&Gold Inc. (США), владеющей крупнейшим в мире золото-меднопорфировым месторождением Grasberg в Индонезии <...>

Автор(ы):Schodde R.
Издание:2011 г., 39 стр.
Язык(и)Английский
Recent trends in mineral exploration - are we finding enough? / Последние тренды в поисках полезных ископаемых - находим ли мы достаточно?

RMG 8th Annual Mining and Exploration Investment Conference 

Overview
• Trends in Exploration Expenditures
- Level of expenditure and key drivers
• Current “Hot Spots” for Exploration 
• Trend in Discovery Rates
- Metal found, Unit Discovery Costs for Au, Cu and U3O8
• Trends in conversion rates (from Discovery > Development)
- Not all discoveries get mined, and those that do may take many years
• Impact of changes in cut-off grade on available resources
- Resources can significantly grow with lower cut-off grades ...needs economies 
of scale, innovation in technology and higher prices to happen
• Are we finding enough metal ?
– Implications on long run commodity prices
• Conclusions

Автор(ы):Dominy S.C., Platten I.M.
Издание:2001 г., 24 стр.
Язык(и)Английский
The occurrence of high-grade gold pockets in quartz reefs at the Gwynfynydd Mine, Wales, United Kingdom: A geological explanation for the nugget effect / Проявление золоторудных гнезд в окварцованных зонах шахты Гвинфинидд

Проявление золоторудных гнезд в окварцованных зонах шахты Гвинфинидд: геологическое объяснение эффекта самородка

Gold-bearing quartz reefs commonly show extremely erratic and unpredictable grade variation, although gross geological continuity may be good. This type of variation is often described as being nuggety or having a high nugget effect and can be measured quantitatively using the semivariogram. Understanding of geological features such as reef texture and structure will provide improved models for the interpretation of assay data, drill core descriptions, etc.

Автор(ы):Boucher A., Marcotte D.
Издание:2001 г., 8 стр.
Язык(и)Английский
The estimation of mineralized veins: A comparative study of direct and indirect approaches / Оценка минерализованных жил: сравнительное изучение приямых и непрямых подходов

The accepted practice for the estimation of thin (2D) vein deposits recommends the use of the grade x thickness service variable (i.e., the accumulation). Grade estimates are obtained indirectly by the estimated accumulation/estimated thickness ratio. This practice stems from the varying support (thickness) problem and the resulting non-additive nature of the grade variable. We compare the actual performance of the direct grade estimation approach used by some practitioners to that of the indirect approach using accumulation. Our simulated and real data indicate that the direct approach is more accurate for point grade estimation where the grade-thickness correlation coefficient is positive (and vice-versa). Moreover, the relative gain of the direct method increases with the (positive) correlation coefficient. This finding contradicts common thinking that the indirect approach should be the preferred method where grade-thickness correlation is strongly positive. Also, for a given positive grade-thickness correlation, the relative gain of the direct method increases with the coefficient of variation of the grade and thickness. 

Автор(ы):Dagbert M.
Издание:2001 г., 5 стр.
Язык(и)Английский
Comments on “The estimation of mineralized veins: A comparative study of direct and indirect approaches,” by D. Marcotte and A. Boucher / Комментарии по "Оценка минерализованных жил: сравнительное изучение приямых и непрямых подходов"

In their paper, Marcotte and Boucher (2001) cast some new light on the old problem of 2D estimation of vein-type deposits with thickness and grade of intercepts. Using a theoretical approach, some extensive simulation experiments and the Walker Lake data, they show that the direct approach (interpolation of grade at points on a regular grid) gives better estimates of the true grade at those points than the indirect approach (interpolation of grade x thickness or accumulation and interpolation of thickness) when there is some positive correlation between grade and thickness and that this better performance increases with the correlation of grade and thickness as well as the variability of both variables. We would like to bring some reservations to that conclusion by showing that even if direct point grade estimates are better than indirect ones, it is not necessarily true for block estimates and in particular for the estimated grade of the whole orebody itself. <...>

Издание:2002 г., 11 стр.
Язык(и)Английский
Resource estimation of structurally complex and discontinuous mineralization using non-linear geostatistics: case study of a mesothermal gold deposit in Northern Canada

Оценка минеральных ресурсов структурно-сложных и прерывающейся минерализации с применением нелинейной геостатистики: на примере изучения мезотермального золотого оруденения Северной Канады

An estimation of resources of structurally complex gold lodes and stockworks represents a challenging task for geoscientists due to the complex geometry of the lodes and discontinuous grade. In the present case study, the resource of a gold stockwork has been estimated by uniform conditioning after the lode has been subdivided into geostatistically defined domains using the indicator probability model.

Издание:Springer-Verlag, 2008 г., 29 стр.
Язык(и)Английский
End-permian to mid-triassic termination of the accretionary processes of the southern Altaids: implications for the geodynamic evolution, phanerozoic continental growth and metallogeny of Central Asia

Позднепермское-раннетриасовое завершение аккреции южных Алтаид: значение для геодинамической эволюции, фанерозойского роста континента и металлогении Центральной Азии

The Altaids is one of the largest accretionary orogenic collages in the world with the highest rate of Phanerozoic continental growth and significant metallogenic importance. It is widely accepted that subduction-related orogenesis of the Altaids started in the late Precambrian and gradually migrated southward (present coordinates). However, it is uncertain when and how the building of the Altaids was finally completed.

Издание:2013 г., 6 стр.
Язык(и)Английский
Rare metal deposits of East Kazakhstan: Geologic  position and prognostic criteria / Месторождения редкоземельных металлов Восточного Казахстана: Геологическая позиция и прогнозные критерии

In the article the features of the formation and metallogeny of the geological structures of Great Altai (Rudny Altai, Kalba-Narym, Western Kalba and Jarma-Saur) which are included into the system of the Central Asian mobile belt are considered. The characteristic of the main types of rare metal minefields of the Kalba-Narymsky belt genetically connected with the Perm granitoid magmatism of the post-conflict orogenny stage of activization is given. The rhythmical and pulsation model of pegmatitovy ore formation in the conditions of the half-closed magmatic system, reflecting the phasic development of mineral complexes from graphic and oligoclase-microcline (barren) to microcline-albite and albite-spodumene ore (Ta, Nb, Be, Li, Sn, etc.) is developed. On the basis of the revealed criteria of ore formation recommendations about the direction of the further researches are made. 

Автор(ы):Heinrich C.A., Neubauer F.
Издание:Springer-Verlag, 2002 г., 8 стр.
Язык(и)Английский
Cu–Au–Pb–Zn–Ag metallogeny of the Alpine–Balkan–Carpathian–Dinaride geodynamic province / Cu–Au–Pb–Zn–Ag металлогения Альпийско-Балканско-Карпатско-Динаридской геодинамической провинции

The Alpine-Balkan-Carpathian-Dinaride (ABCD) belt is one of the world’s oldest mining areas and played a major role in the history of European civilizations, from well before the peak of the Greek and Roman civilizations up untilthe present day. Today, it is Europe’s premier Cu-Au (-Pb-Zn-Ag) province, especially for gold-rich deposits associated with calc-alkaline magmatism, which have become a focus of renewed exploration interest after the political change in the eastern part of CentralEurope. The Alpine–Balkan–Carpathian–Dinaride metallogenic and geodynamic province is part of the AlpineHimalayan orogenic system which extends from western Europe through Iran and the Himalayas to China and Malaysia.

Издание:Elsevier, 2013 г., 54 стр.
Язык(и)Английский
Phanerozoic continental growth and gold metallogeny of Asia / Фанерозойский континентальный рост и металлогения золота Азии

The Asian continent formed during the past 800 m.y. during late Neoproterozoic through Jurassic closure of the Tethyan ocean basins, followed by late Mesozoic circum-Pacific and Cenozoic Himalayan orogenies. The oldest gold deposits in Asia reflect accretionary events along the margins of the Siberia, Kazakhstan, North China, Tarim–Karakum, South China, and Indochina Precambrian blocks while they were isolated within the Paleotethys and surrounding Panthalassa Oceans. Orogenic gold deposits are associated with large-scale, terrane-bounding fault systems and broad areas of deformation that existed along many of the active margins of the Precambrian blocks. Deposits typically formed during regional transpressional to transtensional events immediately after to as much as 100 m.y. subsequent to the onset of accretion or collision. Major orogenic gold provinces associated with this growth of the Asian continental mass include:

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