scholarly journals The development of numerical forecasting systems of primary sources of gold on the results of placer sampling in the example Vagran placer cluster (North Urals)

Georesursy ◽  
2020 ◽  
Vol 22 (2) ◽  
pp. 67-76
Author(s):  
Alexander V. Lalomov ◽  
Anna A. Bochneva ◽  
Roman M. Chefranov
Keyword(s):  
Field Research ◽  
Heavy Minerals ◽  
Primary Sources ◽  
Gold Content ◽  
Highly Qualified ◽  
Placer Gold ◽  
Correlation System ◽  
Gold Sulfide ◽  
Impurity Elements ◽  
Individual Indicator

Based on the results of field research, as well as data from stock reports, two types of placer gold were identified within the Vagran placer cluster, which are indicators of primary mineralization. They are used as benchmarks for developing a digital system for predicting parameters and localizing primary sources of placer gold. Formalized typomorphic characteristics of placer gold (size, roundness, fineness, sorting and content of impurity elements), combined in multiplicative indicators, make it possible to forecast the composition and localization of the primary mineralization with greater confidence than ordinary parameters separately. The data required for such an assessment do not require additional field and highly qualified laboratory studies, they are contained in standard reports on the heavy minerals testing, and, in contrast to the characteristics of individual indicator types of placer gold, they give more stable results. The study of the correlation system allowed to identify characteristic indicators for the primary mineralization of gold-sulfide-quartz and hypogenic-hypergenic types, and to give recommendations for conducting prospecting and exploration in order to identify the primary gold content of the cluster. The proposed method of creating forecast estimates allows to computerize the process of determining the prospects for primary mineralization of territories.

scholarly journals Placer gold occurrences along the major rivers of Nepal Himalaya and their possible primary sources

1996 ◽  
Vol 13 ◽  
Author(s):  
K. P. Kaphle ◽  
P. R. Joshi ◽  
H. R. Khan
Keyword(s):  
Gold Mineralization ◽  
Gold Deposits ◽  
Primary Sources ◽  
Gold Content ◽  
Lower Paleozoic ◽  
Nepal Himalaya ◽  
Placer Gold ◽  
Flood Plains ◽  
River Flood ◽  
Primary Gold

Recent exploration in Lungri Khola area, Rolpa district, midwestern Nepal helped to delineate a discontinuous 1.5 to 40 m thick and about 30 km long primary gold mineralization zone in the Precambrian greenschists and Lower Paleozoic micaceous marbles of the Lesser Himalaya. The gold content in these lodes vary from 0.01 to 6.7 ppm. In eastern Nepal occurrences of primary gold is recorded in quartz-biotiteschist, amphibolite and pegmatite bodies in Sunmai and Bering Khola of Ilam district. Fine flakes of gold also occur in the pyritiferous quartz beds/lenses in chlorite-sericite phyllite and quartzite of Bamangaon polymetallic prospect, Dadeldhura district, far western Nepal. In this prospect the gold content is from 0.2 to 0.8 ppm, and one sample showed up to 14 ppm. Primary gold occurrences are also detected in few irregular quartz-pyrite veins and iron-copper sulphide bearing quartzite lying close to the amphibolite bodies. Some pyrite bearing radioactive quartzite beds in Banku Quartzite of Purchauni Crystalline Complex exposed at Boregad, Bangabagar, Baggoth and Jamari Gad area in Darchula and Baitadi districts, far western Nepal also contain gold. The gold content in the radioactive quartzite varies from 0.2 to 1.2 ppm and in some pyritiferous radioactive quartzite floats it reaches up to 5.06 ppm. The primary gold appears to be of synsedimentary, hydrothermal and possibly volcanogenic in origin. Placer gold is derived from primary sources and deposited at favourable locations along the river flood plains. Further investigations in similar geological terrain may help to identify economically viable primary as well as placer gold deposits in the Nepal Himalaya.

scholarly journals The Internal Structure of Placer Gold of the North-East of the Siberian Platform as a Reliable Search Sign of Primary Sources

2021 ◽  
Vol 906 (1) ◽  
pp. 012082
Author(s):  
Boris Gerasimov
Keyword(s):  
Internal Structure ◽  
Siberian Platform ◽  
Native Gold ◽  
Primary Source ◽  
Primary Sources ◽  
Placer Gold ◽  
North East ◽  
The North ◽  
History Of ◽  
Gold Sulfide

Abstract Typomorphic features of placer gold are carriers of the most important information necessary for the reconstruction of the history of the formation of placer and ore occurrences of gold and can be used as mineralogical criteria in the search for primary sources of placers. The study of these features is relevant for placer areas with unidentified gold sources, which include the territory of the north-east of the Siberian Platform. The internal structure of native gold is one of the most informative typomorphic features is. We studied the internal gold structures of modern placers and conglomerates of the Early Permian age in the north-east of the Siberian Platform. The purpose of the work: to identify the features of the internal structure of placer gold, depending on the chemical composition and the degree of its transformations, as well as the possibility of their use as a prospecting indicator. Structural etching of native gold was performed using the reagent: HCl + HNO3 + FeCl3 × 6H2O + CrO3 + thiurea + water. As a result of the research, it was found that the well-rounded high-grade gold of modern placers has undergone repeated redeposition through intermediate sources. The discovery of slightly rounded gold with an internal structure without signs of exogenous transformation indicates that it entered the modern alluvium from a nearby primary source. This was a prerequisite for setting up ore gold exploration, resulting in identification of apocarbonate hydrothermal-metasomatic formations with disseminated gold-sulfide mineralization were identified. Thus, the features of the internal structures of placer gold in combination with other typomorphic features are additional indications of determining the sources of formation of gold-bearing placers.

scholarly journals Typomorphism of Placer Gold and Prerequisites for the Discovery of Gold Ore Occurrences in the Southern Part of the Lena-Anabar Trough (North-East of The Siberian Platform)

2021 ◽  
Vol 906 (1) ◽  
pp. 012081
Author(s):  
Boris Gerasimov
Keyword(s):  
Siberian Platform ◽  
Primary Source ◽  
Potassium Feldspar ◽  
Primary Sources ◽  
Gold Content ◽  
High Grade ◽  
Alluvial Deposits ◽  
Placer Gold ◽  
North East ◽  
The North

Abstract The article examines the results of exploratory work carried out in the southern part of the Lena-Anabar trough in the north-eastern part of the Siberian platform. Alluvial deposits of the Polovinnaya river, which belongs to the Uele-Udzhinsky placer cluster, were sampled for predictive assessment of commercial prospects for placer occurrences of gold. The mineralogical-geochemical features of the placer gold were studied in order to identify potential primary sources. It is proved that the Mesozoic and Cenozoic deposits are the main sources of gold. Its typomorphic features are small size (-0.5 mm), toroidal and flake shape, shagreen surface with casts of pressing of the minerals, and high fineness (950-999 %). The internal structures of gold particles are represented by thick high-grade shells, translation lines and high-grade intergranular veinlets. Along with this, the discovery of the autochtonous gold of ore habit in the studied gold area suggested the presence of an additional primary source. Very small size (-0.2 mm) and angular-lumpy shapes of the individuals, almost unrounded surface and low fineness are typical features of slightly altered gold. The discovery of small (3-4mm) fragments of hydrothermal-metasomatic rocks in the alluvium of the Polovinnaya river confirms the above assumption. The epigenetic mineral composition of these fragments is represented by pyrite, potassium feldspar, fluorapatite, and quartz. Micro-X-ray spectral analysis determined the smallest (first microns) mineral phases of native gold, argentite, galena, sphalerite and greenockite in them. It is worth noting that the described fragments are quite fragile, and they are destroyed with a slight impact with a steel needle. The fragility of these fragments indicates the close proximity of the rewashed ore occurrences. In addition, increased gold content in small classes of heavy concentrate material of small-volume samples was determined according to atomic absorption analysis. All this together is a prerequisite for the discovery of ore occurrences with finely-dispersed and fine gold. It is assumed that the ore occurrences can be localized in the Anabar-Eekit fault zone, which extends parallel to the Pronchishchev ridge, through the Anabar-Olenek trough, to the Sololiy uplift of the Olenek arch. In the area of the Olenek arch, this zone is associated with superimposed gold-bearing low-temperature hydrothermal mineralization, expressed by K-feldspathization and sulfidization of the Permian deposits.

scholarly journals Criteria for Determining the Genesis of Placers and Their Different Sources Based on the Morphological Features of Placer Gold

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 381
Author(s):  
Zinaida Nikiforova
Keyword(s):  
Native Gold ◽  
Morphological Characteristics ◽  
Gold Deposits ◽  
Primary Sources ◽  
Gold Content ◽  
Placer Gold ◽  
Gold Particles ◽  
Search Criterion ◽  
Different Sources ◽  
Gold Bearing

Based on the identified typomorphic features of placer gold, a set of determined morphogenetic criteria is proposed to identify the genesis of placer gold content and different sources in the platform areas, which allow more correctly selecting search methods and improving the efficiency of forecasting ore and placer gold deposits.Goldparticles larger than 0.25 mm with signs of wind-worn processing indicate the formation of autochthonous aeolian placers.Gold particles with signs of wind-worn processing with a size of 0.1–0.25 mm, forming an extensive halo of dispersion, indicate the formation of allochthonous placers in Quaternary deposits.Deflationary (autochthonous) placers of native gold can be found by the halo of its distribution of toroidal and sphericalhollow forms, which, of course, are the search morphogenetic criterion of aeolian placers.The presence of disc-shaped and lamellar gold particles with ridgelike edges in alluvial placers is typical for placers of heterogeneous origin, formed due to deflation of proluvialplacers.The discovery of pseudo-ore gold in alluvial placers indicates the arrival of gold from intermediate gold-bearing sources of different ages and not from primary sources, which is a morphogenetic criterion for determining different sources of the placer.In modern gold placers, the presence of gold of a pseudo-ore appearance can serve as a search criterion for the discovery of gold-bearing conglomerates with high gold content. The developed method for diagnosing the genotype of placer gold by its morphological characteristics (alluvial, aeolian, pseudo-ore) can be successfully used by industrial geological organizations to search and explore ore and placer gold deposits.

scholarly journals Typomorphic Features of Placer Gold from the Billyakh Tectonic Melange Zone of the Anabar Shield and Its Potential Ore Sources (Northeastern Siberian Platform)

Minerals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 281
Author(s):  
Boris Gerasimov ◽  
Vasily Beryozkin ◽  
Alexander Kravchenko
Keyword(s):  
Native Gold ◽  
Gold Mineralization ◽  
Coarse Fraction ◽  
Gold Deposits ◽  
Primary Sources ◽  
The Arctic ◽  
Geochemical Data ◽  
Placer Gold ◽  
Anabar Shield ◽  
Tectonic Mélange

Precambrian shields and outcropped Precambrian rock complexes in the Arctic may serve as the most important sources of various types of mineral raw materials, including gold. The gold potential of the Anabar shield in the territory of Siberia has, thus far, been poorly studied. A number of primary and placer gold occurrences have been discovered there, but criteria for the prediction of and search for gold mineralization remain unclear. The main purpose of this paper was to study the typomorphic features of placer gold in the central part of the Billyakh tectonic mélange zone in the Anabar shield and to compare them to mineralization from primary sources. To achieve this, we utilized common methods for mineralogical, petrographic, and mineragraphic analyses. Additionally, geochemical data were used. As a result of this investigation, important prospecting guides were identified, and essential criteria for the prediction of and search for gold deposits were elucidated. The characteristics of the studied placer gold were specific for gold derived from a proximal provenance. These characteristics included the poor roundness of the native gold grains, a cloddy–angular and dendritic form, an uneven surface, and a high content of coarse-fraction native gold (0.5–2 mm), which was as high as 24% of the volume of analyzed native gold. In addition, we conducted a study on the mineralogical features of the gold-sulfide mineralization that was disseminated throughout a small exposure area of paleo-Proterozoic para- and orthogneisses in the Anabar shield basement. A comparison of mineral inclusions in the coarse-fraction native gold and mineral assemblages in the ore deposits showed that one of the possible primary sources for placer gold might be small bodies of metasomatically altered orthogneisses associated with large granitoid plutons.

Prospects of primary gold potential in southern Siberian platform based on study results for placer gold morphological and geochemical features

2021 ◽  
pp. 97-114
Author(s):  
Ivan Chetvertakov ◽  
Alexey Ivanov ◽  
Ekaterina Mikheeva ◽  
Tatyana Chikisheva ◽  
Tamara Yakich
Keyword(s):  
Siberian Platform ◽  
Geological Structure ◽  
Gold Deposits ◽  
Primary Sources ◽  
Placer Gold ◽  
Genetic Types ◽  
Study Results ◽  
Geochemical Property ◽  
Geochemical Studies ◽  
Primary Gold

Data on geological structure and minerals of the southern Siberian platform are presented. Placer and primary gold occurrences widespread in this region are briefly characterized. Based on placer gold morphological and geochemical property studies using electron microscopy, its four types are revealed. Conclusions are made about potential primary sources of various placer gold types. Using retrospective data and based on the authors’ placer gold morphological and geochemical studies, Ust-Ilimskaya, Chernorechinskaya and Buraevskaya gold areas are characterized, their prospects for discovering primary gold deposits of various genetic types are determined.

Program Supervisi Klinis di SMA

2019 ◽  
Vol 1 (1) ◽  
pp. 37
Author(s):  
Najibur Rahman ◽  
Hasbi Indra ◽  
Herawati Herawati
Keyword(s):  
High School ◽  
Qualitative Research ◽  
Clinical Supervision ◽  
Learning Process ◽  
Field Research ◽  
School Principal ◽  
Primary Sources ◽  
Teacher Professionalism ◽  
Main Task ◽  
The Right

<p class="15bIsiAbstractBInggris">Supervision is carried out by the principal felt very important because it is of the main task as a principal to improve the professionalism of teachers in the learning process carried out at school. Still, many supervision did not find the desired results because it was not carried out directly by the school principal. Besides, the absence of an appropriate program so that the supervision program does not find the right direction, which results in the achievement of the supervision goals themselves. The purpose of this study is to arrange the right Clinical Supervision Program in Senior High School. The approach used in this research is qualitative research with the type of field research by utilizing primary sources, namely interviews and observations with both the principal and teachers. The results of this study are clinical supervision can improve teacher professionalism because it feels better. It because of the closeness of the principal with the observed teacher. Besides, monitoring carried out directly by the school principal is more targeted and more objective than supervision conducted by the tutor teacher or vice-principal. The importance of a program arranged in carrying out a supervision activity has a significant role because it can direct and measure the success of the supervision carried out.</p><p class="16aJudulAbstrak"><strong>Abstrak</strong></p><p class="16bIsiAbstrak">Supervisi yang dilakukan oleh kepala sekolah dirasakan sangat penting karena merupakan dari tugas pokok sebagai kepala sekolah sebagai upaya untuk meningkatkan keprofesionalan guru dalam proses pembelajaran yang dilaksanakan di sekolah. Akan tetapi. Banyak supervisi tidak menemukan hasil yang diinginkan karena tidak dilaksanakan langsung oleh kepala sekolah. Selain itu, tidak adanya program yang tepat sehingga program supervisi tidak menemukan arah yang benar yang berdampak kepada tidak tercapainya tujuan supervisi itu sendiri. Tujuan penelitian ini adalah menyusun program supervisi klinis di Sekolah Menengah Atas yang baik. Pendekatan yang digunakan dalam penelitian ini adalah penelitian kualitatif dengan jenis penelitian <em>field</em> <em>research </em>dengan memanfaatkan sumber primer yaitu wawancara dan pengamatan baik dengan kepala sekolah maupun para guru. Hasil penelitian ini adalah supervisi klinis dapat meningkatkan profesional guru karena dirasakan lebih baik. Hal ini diperoleh karena kedekatan kepala sekolah dengan guru yang diobservasi. Selain itu supervisi yang dilaksanakan langsung oleh kepala sekolah dilaksanakan lebih tepat sasaran dan lebih objektif dibandingkan dengan supervisi yang dilakukan oleh guru pamong atau wakil kepala sekolah. Pentingnya sebuah program disusun dalam melaksanakan sebuah kegiatan supervisi memiliki peran yang sangat utama, karena dapat mengarahkan dan mengukur keberhasilan dari supervisi yang dilaksanakan.</p>

The native gold extracted in the Amur Region for 150 years

2021 ◽  
pp. 57-62
Author(s):  
ANTON MELNIKOV ◽  
VALENTINE MOISEENKO ◽  
VITALY STEPANOV
Keyword(s):  
Native Gold ◽  
Amur Region ◽  
Gold Production ◽  
Sample Distribution ◽  
Placer Gold ◽  
Porphyry Deposits ◽  
Percentage Points ◽  
Gold Silver ◽  
Production History ◽  
Gold Sulfide

Data on gold production history and typomorphic features of native gold from the Amur province are provided. It is shown that about 1,116 t of primarily placer gold was extracted for 150 years, with primary gold accounting for 23,8 %. Placer gold sample distribution is unimodal with a maximum ranging within 850–925 ‰. Mercury prevails in microimpurities, its content in some clusters reaches the first percentage points. In terms of composition impurities, placer gold corresponds to gold from fields and occurences of gold-quartz and gold-sulfide-quartz formations. Low-fineness gold, (799–700 ‰) less common in placers, resulted from destruction of gold-silver unit sources while that of average fineness (800–900 ‰) was a result of the same process related to gold-polymetallic and gold-sulfide units. Gold-copper-molybdenum porphyry deposits do not form placers. The prospects of primary and placer gold production in the Amur region are defined.

scholarly journals Oral Testimonies on Sai Baba As Gathered During a Field Research in Shirdi and Other Locales in October-November 1985

2020 ◽  
Author(s):  
Antonio Rigopoulos
Keyword(s):  
Andhra Pradesh ◽  
Field Research ◽  
Primary Sources ◽  
Audio Recordings ◽  
Old Men ◽  
The Village

The interviews and audio recordings comprised in this volume are the outcome of a field research to Maharashtra and Andhra Pradesh which took place in October-November 1985 for the preparation of the Author’s BA thesis on the life and teachings of the Indian saint Sai Baba of Shirdi (d. 1918), discussed at the Ca’ Foscari University of Venice in June 1987 (Un maestro dell’India moderna: il Sāī Bābā di Śirḍī. L’uomo, l’ambiente, gli insegnamenti). The conversations of each day are preceded by excerpts from the Authorʼs diary. These testimonies record the words of various people in the village of Shirdi and other locales, among whom are the last old men who knew Sai Baba: Balaji Pilaji Gurav, Bappaji Lakshman Ratna Parke, Martanda Mhalsapati, Pandharinath Bhagavant Gonkar, Tukaram Raghujiv Borawke, and Uddhavrao Madhavrao Deshpande. While in Shirdi the Author was also able to interview Uttamrao Patil, son of Tatya Kote Patil, and in Mumbai he had the privilege of meeting Swami Ram Baba, who first met the saint in 1914. Taken altogether, these conversations are primary sources for the study of Sai Baba and may help to contextualize Shirdi as a pilgrimage place in the mid-1980s.

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