This research focuses on the study of mineral parageneses of metamorphites that outcrop in the Nganda-Tsundi region and its surroundings located in the territory of Tshela, in order to obtain coherent information regarding the degrees of metamorphism that have contributed to the transformation of pre-existing rocks. The compilation of field (macroscopic analysis), laboratory results and previous work results revealed seven main petrographic facies in the study area: namely the biotitoschist, chloritochist, amphibolite, quartzophyllade, sericitoschist, garnet metaquartzite and graphitic shale. Mineralogical assemblages enabled us to distinguish three degrees of metamorphism in the study area: low-grade, medium-grade and high-grade. By combining structural data, such as the schistosities observed in the field and during microscopic in thin sections observations, with these last mineralogical observations, we can conclude that the rocks of our study area were affected by two distinct orogenic events namely: the Tadilian orogeny of Proterozoic age which is responsible for two types of schistosity which affected the chloritoschists and the West-Congolian Neoproterozoic orogeny, is responsible for a single schistosity affecting the other petrographic facies (biotitoschist, amphibolite, quartzophyllade, sericitoschist, metaquartzite and graphitic schist).

The major issue of this study is to identify the causes and consequences of the fire in the city of Kinshasa. The aim is to analyze the statistical data of the fires recorded by the Corps of Firefighters of Kinshasa (in acronym CSPK) to know and understand the causes in order to characterize the consequences in order to better prevent them. This study is based on the fact that knowledge of the origins of the fire is the foundation of any effective prevention policy. The method of observation and the documentary method followed by investigations in the field (in particular surveys by interview with the victims) and laboratory work helped us to arrive at the results. The results obtained from our investigations and resulting analyzes show that anomalies in the use of electric current, poor management/handling or misuse of dangerous products or equipment (candle, flammable products, etc.), material failures on the part of the CSPK are the main causes of fires in the city of Kinshasa. The consequences range from material losses to those of human life, including serious injuries and burns to people who are victims of the fire.

The formations of this region are essentially metamorphic Granit-Gneissic of which the term granitic is descended of the granitization-migmatization of Kimezien. Two tectonic periods have been demonstrated by double schistosities noticed to the level of the micas. The geochronology of these formations will be able to bring more precision on the age of these formations and that has the end will confirm or will invalidate the thesis to evoke in this survey.

In the city of Kinshasa, the poor management of waste (plastic bags, packaging, household waste and others) poses enormous problems of insalubrity and degradation of nature, thus causing the development of endermic diseases (malaria, typhoid, etc.). Despite the efforts made by the municipal authorities, this problem of insalubrity in the Congolese capital still remains. Good waste management through public trash cans will generate positive and negative impacts on the Kinshasa environment. On this, we propose in this study some strategies for the distribution of new locations according to the methods adopted. The data obtained in the field and the results of their analysis have made it possible to deduce that the rate of insalubrity has increased over the past six years due to poor waste management. To remedy this persistent problem, we ask the population of the District of Mont-Amba to properly manage their waste by installing garbage cans and to participate in community work. To the authorities, we are asking for strong awareness raising regarding waste management and the installation of public trash cans in appropriate places outside neighborhoods.

This work consists of a sedimentological and paleoenvironment study of the carbonate rocks of the Mbuji-Mayi Supergroup dated to the Neoproterozoic of the Bena Kabongo quarries. Macroscopically, two lithofacies have been determined, namely: limestone and dolomite. Field observations show us that the base of the sequence is dominated by dark fine-grained limestones. The summit part is represented by fine-grained gray limestones that alternate with brownish dolomite. Based on seven thin sections, a microscopic observation was carried out and allowed us to detect three microfacies, namely: intrasparites, intramicrites and intraclastics, all representing a standard sequence of the sedimentary series. This sequence shows the evolution of the deposit going from a subtidal zone to an intertidal zone. Analysis of the microfacies of the sequence shows that the strata were accumulated on an internal ramp in the shallower and more oxidizing conditions with stromatolitic flora.