Papers by Alberto Bustamante
Apuntes Revista De Ciencias Sociales, 1979
Total reported gold resources in Peru is about 192 Moz. Gold production in Peru was 4.9 Moz in 20... more Total reported gold resources in Peru is about 192 Moz. Gold production in Peru was 4.9 Moz in 2013, which was ranked first in Latin America and sixth in the world. Historic cumulative gold production in Peru is 118 Moz, and production from main gold belts including Miocene epithermal belt, Carboniferous-Permian orogenic gold belt and Upper Cretaceous intrusion-related gold belt corresponds to 84%. Most of production areas are located in Northern part of Peru, which corresponds to 63.5% of the total domestic production. Annual production onces in Yanacocha mine and Alto Chicama were 1 Moz and 0.606 Moz in 2013, which were ranked first and second in Peru, respectively. Gold production in Peru is expected to be 6.5 Moz in 2017. To accomplish the expected production, ongoing 14 projects should be developed to the production stage in three years.
The copper mineralization in Peru is intimately associated with porphyry Cu deposits and subdivid... more The copper mineralization in Peru is intimately associated with porphyry Cu deposits and subdivides into three porphyry Cu belt as Paleocene, Eocene-Oligocene, and Miocene. Up to now, the total copper production from them reach 28 Mt Cu. The total copper production from the Paleocene Cu belt, including Toquepala, Cuajone, and Cerro Verde, accounts for approximately 57% of total copper production from Peru. But focusing mineral exploration on middle southern (Eocene-Oligocene) and northwestern part (Miocene) of Peru results in new discoveries, including La Granja, El Galeno, Las Bambas, Toromocho, and Rio Blanco, which have an estimated annual production more than 200,000 t Cu. In addition to them, thirteen Cu deposits are discovered from the Paleocene, Eocene-Oligocene, and Miocene Cu belts. Thus, Peru is supposed to produce Cu production from 2014 and increases annual production from 143 Mt Cu in 2012 to 490 Mt Cu in 2019. Due to new discoveries, it is expected that mineral explora...
Economic and Environmental Geology, 2015
Oxford Medical Case Reports, 2014
Economic and Environmental Geology, 2013
Memórias do Instituto Oswaldo Cruz, 2007
Given that highly active antiretroviral therapy (HAART) has been demonstrated useful to restore i... more Given that highly active antiretroviral therapy (HAART) has been demonstrated useful to restore immune competence in type-1 human immunodeficiency virus (HIV-1)-infected subjects, we evaluated the specific antibody response to influenza vaccine in a cohort of HIV-1-infected children on HAART so as to analyze the quality of this immune response in patients under antiretroviral therapy. Sixteen HIV-1-infected children and 10 HIV-1 seronegative controls were immunized with a
Hyperfine Interactions, 2006
Natural iron oxides are very common in nature and are the main components of many minerals, rocks... more Natural iron oxides are very common in nature and are the main components of many minerals, rocks and soils. There are a great variety of these minerals in Peru, especially in the Andes region. The mineral studied was extracted from the Taraco District in the Huancané Province of the Puno Region. The extracted sample is a yellowish mineral with very small particles which is called limonite. X-ray diffraction indicates the presence of goethite as the principal mineralogical phase and quartz as the secondary phase. The 57 Fe Mössbauer spectra at room temperature show broadened spectra that were fitted using a distribution model. The most probable field of the magnetic component is 21T, corresponding to the presence of small particles of goethite, confirmed by the 4.2 K spectrum. MS of the calcinated sample in air at 900°C show the presence of two hematite sextets, one related to bulk particles and another to surface particles. Chemical analysis using Scanning Electron Microscopy and Energy Dispersive X-ray Spectrometer indicates that O and Fe are the major components; other elements such as Al, Si, Mg and Ca are also present.
Hyperfine Interactions, 2010
The analysis by X-ray diffraction of a mining sample collected from Oshno hill, which is located ... more The analysis by X-ray diffraction of a mining sample collected from Oshno hill, which is located in the District of Chavín de Pariarca, Huamalies Province, Huanuco, Peru, indicates the presence of lepidocrocite (γ-FeOOH) and goethite (α-FeOOH). The room temperature Mössbauer spectrum (MS) doublet with broad lines displays hyperfine parameters corresponding to the presence of particles of iron hydroxides smaller than 100 Å in a superparamagnetic regime. The measurement of a MS at 4.2 K allowed confirming the presence of goethite and lepidocrocite (with average magnetic fields of 49.21 T and 44.59 T, respectively).
Hyperfine Interactions, 2007
Obsidians from major Ecuadorian sources (outcrops) were analyzed by electron spin resonance, SQUI... more Obsidians from major Ecuadorian sources (outcrops) were analyzed by electron spin resonance, SQUID magnetometry and 57 Fe Mössbauer spectroscopy. If the last technique allows to discriminate obsidians from the Quiscatola source, an association of ESR with SQUID magnetometry permits to differentiate obsidians from the sources of Cotopaxi volcano, from the Quiscatola and Mullumica-Callejones sources of the Chacana caldera and to infer that the 12 analyzed obsidians from the pre-Hispanic site of La Maná come from the Mullumica-Callejones source.
Hyperfine Interactions, 2007
ABSTRACT We present the preliminary results of a provenance study of obsidians samples from Cerri... more ABSTRACT We present the preliminary results of a provenance study of obsidians samples from Cerrillos (ca. 800–100 b.c.) using Mössbauer Spectroscopy. The Cerrillos archaeological site, located in the Upper Ica Valley, Peru, is the only Paracas ceremonial center excavated so far. The archaeological data collected suggest the existence of a complex social and economic organization on the south coast of Peru. Provenance research of obsidian provides valuable information about the selection of lithic resources by our ancestors and eventually about the existence of communication routes and exchange networks. We characterized 18 obsidian artifacts samples by Mössbauer spectroscopy from Cerrillos. The spectra, recorded at room temperature using different velocities, are mainly composed of broad asymmetric doublets due to the superposition of at least two quadrupole doublets corresponding to Fe2+ in two different sites (species A and B), one weak Fe3+ doublet (specie C) and magnetic components associated to the presence of small particles of magnetite. Multivariate statistical analysis of the Mössbauer data (hyperfine parameters) allows to defined two main groups of obsidians, reflecting different geographical origins.
Hyperfine Interactions, 2006
This report is about the X-ray diffraction and Mö ssbauer studies of three impactite samples deno... more This report is about the X-ray diffraction and Mö ssbauer studies of three impactite samples denominated PMe-8, PMe-9 and PMe-11 from Huamalies Province in Huá nuco Region, Peru. When terrestrial rocks are submitted to pressures higher than 60 GP, the majority is completely melted, forming a kind of glass called impactites. X-ray diffraction indicates the presence of quartz as the principal mineralogical phase in all samples. The 57 Fe Mö ssbauer spectra at room temperature of samples PMe-8 and PMe-9 show broadened spectra that were fitted using a distribution model. The most probable field of the magnetic component is 34 T, corresponding to the presence of small particles of goethite, confirmed by the 4.2 K spectrum. For the sample PMe-11, the MS showed the presence of well crystallized hematite.
Plos One, 2009
Objectives: Household contacts (HHCs) of pulmonary tuberculosis patients are at high risk of Myco... more Objectives: Household contacts (HHCs) of pulmonary tuberculosis patients are at high risk of Mycobacterium tuberculosis infection and early disease development. Identification of individuals at risk of tuberculosis disease is a desirable goal for tuberculosis control. Interferon-gamma release assays (IGRAs) using specific M. tuberculosis antigens provide an alternative to tuberculin skin testing (TST) for infection detection. Additionally, the levels of IFNc produced in response to these antigens may have prognostic value. We estimated the prevalence of M. tuberculosis infection by IGRA and TST in HHCs and their source population (SP), and assessed whether IFNc levels in HHCs correlate with tuberculosis development.
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Papers by Alberto Bustamante