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ABSTRACT:The present work investigates the relationship between whole-rock geochemistry and stable isotope composition from carbonatites belonging to the Tapira, Araxá, Salitre, Serra Negra, Catalão I, and Catalão II alkaline-carbonatite complexes of the Alto Paranaiba Igneous Province (APIP), central Brazil and from the Jacupiranga Complex, of the Ponta Grossa Province, southeast Brazil. The APIP complexes are ultrapotassic, comprising bebedourites, phoscorites, nelsonites, and carbonatites, whereas Jacupiranga is a sodic complex composed of ijolite-series rocks, syenites, carbonatites, and alkaline gabbros. The geochemistry data allied to mineralogical constraints allowed us to classify the carbonatites into five groups, and to devise a chemical index (BaO/(BaO+SrO)) to gauge the magmatic evolution of the studied carbonatites.The APIP carbonatites evolve from apatite-rich calciocarbonatites toward Ba-, Sr-, and rare earth element (REE)-rich magnesiocarbonatites. This evolution is mostly driven by apatite, phlogopite, dolomite, and calcite fractionation and consequent enrichment in monazite, norsethite, and strontianite. Stable isotope data show a wide diversity of petrogenetic processes in play at the APIP, relatively to the Jacupiranga Complex, which is interpreted as a result of the shallower intrusion levels of the APIP complexes. Such shallower emplacement, at low lithostatic pressure, allowed for a complex interplay of fractional crystallization, liquid immiscibility, degassing, and interaction with hydrothermal and carbohydrothermal systems. KEYWORDS: INTRODUCTIONBrazilian alkaline provinces have been studied by a range of techniques such as whole-rock geochemistry, mineral chemistry, stable and radiogenic isotope geochemistry, with a range of petrogenetic aplications (Gomide et al. 2013, Barbosa 2009, Cordeiro et al. 2011, Grasso 2010, Ribeiro 2008, CominChiaramonti et al. 2001, Traversa 2001, Andrade et al. 2002, Huang et al. 1995, Santos & Clayton 1995, Ulbrich & Gomes 1981. We aim to contribute to the knowledge of carbonatite petrogenetic evolution, investigating the relationships between whole-rock geochemistry and stable isotope geochemistry data, reporting geochemical and isotopic data from carbonatites of the Late-Cretaceous Alto Paranaíba Igneous Province (APIP), and discuss their implications for magma evolution, both at single-complex and Province-wide scales. The results obtained are compared with the Early-Cretaceous Jacupiranga carbonatite complex, in the Ponta Grossa Province.Alkaline rocks and alkaline-carbonatite associations include highly variable petrographic types and correspondingly extensive nomenclature. We adopt the nomenclature proposed by Le Maitre et al. The APIP alkaline-carbonatite complexes are multistage intrusions formed by rocks derived from the bebedourite, carbonatite, and phoscorite series, which are related to each other by a complex interplay of fractional crystallization, liquid immiscibility, and degassing (Brod et al. 2004, Ribeiro 2008, Barbosa 2009, Cordeir...

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Abstract. Gender affects all aspects of life, and the working and learning environments of science, technology, engineering and geosciences present no exception. Gender issues concerning the access, permanence and ascension of women in exact sciences and Earth sciences careers in general are related to a variety of causes. The underrepresentation of women in science communications, sexual or moral harassment caused by professors and colleagues during undergraduate and graduate ages or the overloading of girls, when compared to boys, with housework during early school ages are some examples mentioned in the literature. In other words, the gender imbalance in science and technology careers may be seen as the result of a series of structured oppression suffered by women of all ages. In this context, we propose the development of an education package that is designed to understand these processes at different levels. One of the tools of this package is known as the “Theatre of the Oppressed”. Elaborated on by Augusto Boal in the 1970s, the Theatre of the Oppressed uses theatre techniques as a means of promoting social and political changes. Usually, a scene takes place that reveals a situation of oppression. The audience become what is called “spect-actors”, where they become active by exploring, showing and transforming the reality in which they are living. In the context of gender issues in exact sciences careers, the students can stage situations that reveal the subtle actions of power relations that usually put women in subservient positions. Our experience showed that, even though the acting is based on fiction, the spectators learn a great deal from the enactment because the simulation of real-life situations, problems and solutions stimulates the practice of resisting oppression in reality from within a setting that offers a safe space to practise making a change.

<p><strong>Abstract.</strong> Gender affects all aspects of life, and the working and learning environment of science, technology, engineering and geosciences presents no exception. Gender issues concerning access, permanence and ascension of women in exact and earth sciences careers, in general, relates between other causes, to the underrepresentation of women in science communications, sexual or moral harassment caused by professors and colleagues during undergraduate and graduate ages, or the overload of housework for girls, when compared to boys, during early school ages. In other words, gender imbalance in science and technology careers may be seen as the result of a series of structured oppression suffered by women of all ages. In this context, we propose the development of an education package designed to understand these processes at different levels. One of the tools of this package is known as the Theatre of the Oppressed. Elaborated by Augusto Boal in the 1970s, the Theatre of the Oppressed uses theatre techniques as means of promoting social and political changes. Usually, a scene takes place, revealing an oppression situation. The audience becomes what is called <q>spect-actors</q>, where they become active by exploring, showing, and transforming the reality in which they are living. In the context of gender issues in exact sciences careers, the students can stage situations that reveal subtle actions of power relations that usually put women in subservience places. Our experience showed that even though the acting is fiction, the spectators learn much from the enactment, because the simulation of real-life situations, problems, and solutions stimulates the practice of resistance to oppression in reality, within a condition that offers a <q>safe space</q> for practising making a change. The package also includes a set of laboratory routines based on the work of female scientists, directed to students from 12 to 18 years old. The idea of the labs is to work as a school reinforcement on natural sciences disciplines, and to give visibility to women in science, improving issues such as underrepresentation and mistrust in women work. We show the evaluation of learning efficiency by assessing the results of a quiz.</p>

<p><span>The gender gap is measured globally by the World’s Economic Forum in four key areas: economic participation and opportunity, educational attainment, health and survival, and political empowerment. According to the 2020 Global Gender Gap index, it will take us nearly 100 years to get gender parity. Also according to the World’s Economic Forum report, if we consider the fastest growing professions of the future, a critical data reveals a problematic situation: women form only 26% among people with AI and data skills, 15% among people with engineering skills and 12% among those with cloud computing skills. Education is thus an important key to embed gender parity into the future. Today, 55% of working-age women are in the labour market, against 78% of men. This gap can increase even more if we do not include young girls in Science, Technology, Engineering and Mathematics (STEM) courses. Gender issues concerning access, permanence and ascension of women in STEM careers, in general, relates to various aspects. Between other elements, we point the underrepresentation of women in science communications, sexual or moral harassment caused by professors and colleagues during undergraduate and graduate ages, or the overload of housework for girls, when compared to boys, during early school ages. In other words, gender imbalance in STEM careers is the result of a series of structured oppression suffered by women of all ages. In this context, we developed a set of laboratory routines based on the work of female scientists, directed to students from 12 to 18 years old, at the Planaltina Campus of the University of Brasília. The University of Brasília is the 4th most prominent university in Brazil, and its resources are distributed between four camps. Planaltina Campus is situated 40 km away from the main campus. In recent research, it has been shown that only 30% of Planaltina young population has the intention of accessing the university. From those, only 15% pretend to study exact and earth sciences. Thinking about the World’s Economic Forum alert about professions of the future, we felt the necessity of promoting a program to capacitate, inform and demystify tabus from exact sciences among high school students, especially among girls. The activities start with the rescue of a prominent female scientist in the field that will be worked on that day, followed by a pedagogical transcript of her work. We conduct a hands-on laboratory within the University of Brasília infrastructure. The idea of the labs is to work as a school reinforcement on natural sciences disciplines, and to give visibility to women in science, improving issues such as underrepresentation and mistrust in women work. We will present the results of an implemented questionnaire and also comment about the challenges of our experience. </span></p>

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