This study examined the vulnerability of rural adolescent girls to child marriage. In particular, the research explored how twenty adolescent girls who were conveniently recruited from a resource-poor rural community in the Manicaland Province of Zimbabwe understood and communicated their vulnerability to child marriage. The adolescent girls who participated in this study emerged from a resource-poor context where they were oppressed by poverty, heteropatriarchy, and prevailing gender norms characterized by the sociocultural and economic ecologies of Manicaland. The study used focus group discussions and in-depth interviews to gain insight into the adolescent girls` understandings of their vulnerability to child marriage. Analysis in the study was informed by two theories. First, feminist theories provided a framework for understanding how gender shaped the lives of rural adolescent girls, and in turn, rendered them socially inferior and susceptible to the experience of child marriage. Second, the social norms theory provided a framework for understating how prevailing social and cultural norms endangered marginalised and exposed adolescent girls to perilous practices such as child marriage. The data generated in the study were analysed using a thematic approach. Findings revealed that the adolescent girls who participated in this study were vulnerable to child marriage. They understood their vulnerability to child marriage in several ways that were tied to their gender identities, their inferior social positions as girls, enduring household and community poverty, perilous gender norms and inequality, heteropatriarchy, and religious and cultural norms. Within this context, the participants reported that their agency to resist child marriage was limited. The findings have implications for ameliorative programming and interventions that are focused on giving adolescent girls safe spaces and the voice to challenge gender, sociocultural, and the heteropatriarchy that rendered them vulnerable to child marriage.

In 2011, the Bill and Melinda Gates Foundation launched the Reinvent the Toilet Challenge (RTTC) to provide sustainable, sanitary amenities for 2.6 billion people who lack access to suitable toilet facilities. 16 research groups, including the Pollution Research Group, were awarded grants to develop concepts and to design prototypes of a toilet that would provide safe and sustainable treatment of human waste. To this end, various technologies were proposed and developed for the treatment of urine, to recover valuable nutrients and water. However knowledge of the thermophysical properties of urine is key in the engineering design and optimization of urine treatment technologies. The aim of this project was to provide the RTTC grantees with experimental data that will inform optimised designs of their urine treatment units, particularly those required for the design and optimum operation of thermal and membrane separation processes. The properties investigated include: vapour pressure; osmotic pressure; electrical conductivity; and density. To investigate the thermophysical properties of urine, synthetic solutions of hydrolysed urine were prepared at a series of concentrations, up to 10 fold. High precision measurements were undertaken for each property at temperatures ranging from 293 to 373 K. Vapour pressure was measured using a static apparatus and osmotic pressure data was calculated from the vapour pressure measurements. The density of the solutions was measured using an Anton Parr DMA 5000 densimeter that uses the vibration principle and electrical conductivity measurements were performed using a commercially available dip style cell (YSI model 3200). Modeling of the experimental data was undertaken to assist the design engineer to calculate the thermophysical properties from the composition of hydrolysed urine. Two existing techniques for modeling were applied. In the first method, a geochemical speciation software, PHREEQC, was used to determine the chemical equilibria and distribution of the ions in the urine solutions at varying temperatures and concentrations. The speciation data was incorporated into thermodynamic models to predict the properties of the urine solutions. In the second technique, existing correlative models were used to fit the experimental data to best fit equations. These models can be incorporated into computer software used in chemical engineering design processes. The accuracy of both techniques was verified by comparing the model calculations to the experimental data. The calculated properties, using both modelling techniques, were in good agreement with experimental data, and the average deviations were within ±2.0% for the studied concentration and temperature ranges. In conclusion, cases studies were done, to demonstrate the use of the urine data and models in the design of a multiple effect evaporator, thermal recompression evaporator, forward osmosis and reverse osmosis processes.

Narrow optical absorption band of fullerene based organic photovoltaic (OPVs) is one of the challenges to produce efficient polymer based solar panel that compete with inorganic counter part. There have been efforts to mitigate the challenges in the past but not enough to overcome all the problems. Plasmon light trapping using metal nano-particles (NPs) incorporated into the organic films is one of the mechanisms being investigated intensively in recent years. Excited plasmon meta nano-partices can dephase in number of ways that could assist in improving photon harvesting as well as charge transport processes in thin film organic solar cells without compromising the optimum thickness of the photoactive medium. The most investigated metal NPs are gold (Au) and silver (Ag) NPs due to their excellent plasmonic and light scattering properties. However, due to their scarcity and cost, several other metallic NPs have also been considered alternative options. Furthermore, mono metal NPs tend to possess high scattering coefficients but low absorption coefficients or vice versa. As a result, several nano-composites of NPs with differing scattering and absorption coefficients have been synthesized and studied. In this study, we have investigated the effect of inexpensive, solution processed and environmentally friendly metal NPs in organic solar cell based poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend solar absorber. Metal nanocomposites using metals such as zinc (Zn), copper (Cu), Ag, manganese (Mn) and sulphur (S) were synthesized via simple low temperature colloidal chemistry. These nano-composites were bimetallic (copper coated with silver, Cu@Ag), zinc sulphide (ZnS), zinc oxide (ZnO) coated with Ag (ZnO:Ag) and zinc sulphide doped with manganese (ZnS:Mn). The size, chemical composition and morphology of the synthesized NPs were studied using high resolution scanning electron microscopy (HRSEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (EDS/EDX). X-ray diffraction (XRD) was used to study their crystalline structure. The optical properties of the NPs in deionized water were studied using UV spectroscopy (UV-Vis). SEM analysis of the NPs showed various structures which mainly consisted of core shell type particles agglomerated together to form large clusters of nano-composites. EDX chemical composition analysis showed no significant impurities. This was consistent with the XRD which showed no diffraction peaks corresponding to impurity. HRTEM analysis confirmed the formation of a core-shell type structure for Cu@Ag with Cu core. Inter-planar (d-spacing) obtained via HRTEM compared very well with those obtained via XRD analysis. The NPs were incorporated either within the photoactive layer or the hole transport layer (HTL) of the solar structure. Significant enhancements on the optical and electrical properties of the OPV devices with NPs were observed when compared to pristine devices. Different NP concentrations were investigated ranging between (1 - 10 )wt% relative to the absorber blend molecules. In some cases, the effect of solvent additives such as dimethyl sulfoxide (DMSO) at 5 wt% was used together with NPs in the HTL to boost the charge transport processes. The enhanced optical absorption, and electrical properties observed as increased current-densities (J), fill-factors and charge carrier mobilities resulted to improved power conversion efficiencies (PCEs) with increases exceeding 100 % when compared to pristine devices. The open-circuit voltages for all devices remained relatively unchanged. The enhancements in the optical and electrical properties which resulted to improved PCEs were attributed to strong light trapping through scattering by NPs and local surface plasmon resonance (LSPR) excitation on the metal-semiconductor interface. Light scattering at different angles into or within the photo-active layer increases its effective optical path length and hence more photons are absorbed. The thesis presents a series of experimental investigations on recently fabricated thin film organic solar cells with/without metal NPs at various concentration.

Electricity price forecasting has turned into a very essential element for both public and private decision making. Both shortage of supply of electricity and electricity cost still remains the country’s most biggest problems and needs to be addressed decisively. Apart from the demand and supply side of electricity, electricity cost is an important part of electricity delivery. Therefore, the accurate estimation of electricity cost and it’s maintenance is an important part of the country’s electricity supply strategy. The main aim of this study is to forecast the cost of rectifying or attending to electricity faults. The study demonstrates that the AutoRegressive Integrated Moving Average (ARIMA), AutoRegressive Integrated Moving Average with exogenous variables (ARIMAX), Vector AutoRegressive (VAR) and Random Forest methods are capable of producing accurate forecasts of costs associated with attending to reported faults. In this study, we analyse the costs of attending to electrical faults in the Bethlehem and Bloemfontein areas of the Free State region of South Africa, from 4 January 2012 to 3 June 2017, using univariate and multivariate ARIMA, ARIMAX, VAR and Random Forest models. ARCH and GARCH models are also used to model the volatility found in the daily costs data. The model developed based on these data can be used to forecast future faults costs and can help policy makers with planning decisions.

The level of under-five child mortality is an important indicator of economic, social and health development of the nation. In the last two decades, substantial progress has been made in improving under-five child mortality globally, with deaths dropping among children under the age of five years from approximately 12 million in 1990 to about 6.3 million in 2015. However, significant strides to address the key risk factors are still needed in the Sub-Saharan Africa region if they are to achieve the Sustainable Development Goals 2030. The key objective of the study is to identify key factors associated with mortality of children under the age of five years in South Africa. In order to identify these factors, the study used different statistical models that accommodate a binary response variable. Models used include Logistic Regression, Survey Logistic Regression, Generalized Linear Mixed Models and Generalized Additive Models. Although logistic regression is useful in modelling data with a dichotomous outcome, it is not suitable for modelling data obtained through a complex survey that incorporates weights, stratification and clustering. Survey logistic regression is used to model the relationship between binary dependent and the set of explanatory variables by making use of the sampling design information. In this case, the inclusion of random effects in the model results in generalized linear mixed models (GLMM). These models are an extension of linear mixed models that allow response variable from different distributions, such as binary responses. One can think of GLMM as an extension of generalized linear models (e.g. logistic regression) that combine both features of fixed and random effects. These statistical models assume linearity parametric form for the explanatory variable. However, this assumption of linear independence of response on covariates may not hold. Hence, we introduce generalized additive models (GAM). The GAM models show some non-linear relationship between the response variable and some covariates. The results showed that, the size of child at birth, breastfeeding, birth order number, ethnicity, number of children 5 under, total children ever born, source of drinking water and province were significantly associated with under-five child mortality. The study concludes that prolonged breastfeeding, improved health services and source of water are among the main factors to decline under-five child mortality further. Therefore, the study suggests that there is a need to strengthen child health interventions in South Africa to reduce the under-five mortality rate even more in order to achieve sustainable development goals (SDG) 2030.

The construct Smart City has gone through a few phases in the last decades. Today there is still no consensus on an accurate definition of Smart City, even though a few concepts are now accepted by most stakeholders, establishing frameworks heading to enhance the quality of life of citizens, sustainable development and economic competitiveness, and, most importantly, the optimal balance between these. Starting from the framework of the Smart City model as conceptualized by the developed world, this research attempts to critically analyse the challenges and barriers to a transition and upgrade of such a model for implementation in developing countries, particularly in the Southern Africa. The mid-term future trends in the region create a huge expectation and concern internationally. Factors like the considerable demographic increase in the post-colonial Africa, the massive migration from the rural areas to cities and the shift from the manufacturing world pole in the East to the African continent predict a remarkable dynamic and vibrant scene in the near future. Stressing the ability of the region to respond to these challenges is starting to gain the attention of scholars and organizations internationally. However, it is important to say that most of the research studies point to both, the solution of dramatic situations related to poverty and underdevelopment, and secondly, the market prospect studies that research the economic potential of the region to foreign capital. Moreover, regarding urban systems, most African governments have scarce and unreliable data. Therefore, looking from a local perspective, it is fair to explore ways Africa and Africans are able to cope with the challenges to come. Not only to make the place attractive to outsider eyes but to increase the quality of life and opportunities for local people through selfmanagement. Africa has undergone through a long history of catastrophes in recent times, with horrendous impact on the population. Yet, a proved resilience makes room for hope in a better future, away from a patronizing management by external forces. Part of this research stresses the feasibility of tailor made solutions to cope with future challenges from a local perspective in the era of globalization. International agencies tend to rate performance in multiple fields based on worldwide standards. Taking into account the use of a series of indicators as a tool to rationalize (evaluate) the performance of any particular field of human action; the measurement of those indicators can vary from region to region. In such resilient environment as described above, the aim of this research is to identify sustainable ways for long-term implementation of up to date technologies in Southern African cities for an effective leapfrog that would bring Southern Africa up to nowadays standards without losing local references. A deep dive into the literature about current technologies and the African city represents the starting point of the methodological approach in order to understand localities and real challenges. The research looked at worldwide urban trends and aims to extract those parameters that are meaningful to Africa today. In order to validate the findings of the research, a case study focussed on specific urban challenges has been identified: the Umgeni River estuary in eThekwini municipality is representative of the confluence of multiple urban dynamics: environmental concerns, lack of municipal services, climate change vulnerability, ocean pollution, poverty, regional business, mining, commercial activities, informal settlements and formal planning. The waste sector in particular, typically undermined in the Global South, has been identified as a potential common thread across the aforementioned urban dynamics. The application to the case study of the lessons learnt through the study of the smart city and urban sustainable resilience highlights the readiness of the Southern Africa city and unlocks a discussion about sustainable urban growth. The results indicate a dual scenario, concerning yet optimistic: there are great disparities between the aspirations from city managers and policy makers, and the conflicted reality at ground level. The pressure due the competitive agenda to render Southern African cities appealing in order to gain foreign economic attention could fade as local communities improve their life condition and strength local markets: “Africa by Africans for Africans”. Two important factors can make this shift possible: one is the presence of strong academic institution with great number of strong collaborations with organizations of great reputation. The case study proves a great interest to assist with solutions to African matters by the international community, but probably not in the way city managers expect. The second one is the advantage that can be taken from the “already made” infrastructure fabric, re-programming the initially “colonial-conceived extractive economic vision” towards social gain.

Many natural products and pharmaceuticals with a broad range of biological activities constitute one or other heterocyclic scaffolds. In pursuit of new synthetic methodologies for diverse heterocyclic compounds, the Multicomponent Reaction (MCR) is an advanced strategy to develop and design versatile organic molecules with high atom economy in a short period. Major advantages of MCRs is the reaction takes place in a one-pot strategy with no need for the separation and purification of intermediates. The synthesis of diverse heterocyclic scaffolds using the MCR strategy can be achieved, and is on the increase. Green Chemistry is an emerging branch of synthetic chemistry, which is to design sustainable synthetic protocols from easily available starting materials and non-corrosive solvents. One fundamental aspect of green chemistry is the reusability of materials and reducing waste. This allows chemists to consider heterogeneous catalysis in reactions because it is easy to separate from the reaction mixture and is reusable. Ease in handling, greater chemo-regio selectivity, and thermal stability are the added advantages of heterogeneous catalysis. Heterogeneous catalysis using mixed metal oxides is gaining importance due to the tuning of surface properties of materials, i.e., one is able to design the catalyst as per requirement by loading/doping of necessary metals on supports. Among many support materials, zirconia gained prominence due to its higher surface area and amphoteric surface properties, which make it an ideal catalytic support. Having a high surface area is advantageous for a reaction to takes place on the surface, which provides necessary active sites to accelerate the reaction. This research was designed to synthesize various novel core N-heterocyclic moieties by using zirconia-supported mixed metal oxide catalysts. During the study, an attempt was made to develop fast reaction protocols to synthesize various pyridine, pyrimidine and pyrazole derivatives with excellent yields using green solvents and mild conditions. These new protocols demonstrated efficacy and high selectivity under eco-friendly conditions. The following six series of reactions were studied: 1. Synthesis of eleven novel functionalized 1,4-dihydropyridine derivatives by using V2O5/ZrO2 as catalyst for the multicomponent reaction using various aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione, acetoacetanilide and ammonium acetate. 2. A one-pot protocol to synthesize novel functionalized halopyridine derivatives by using RuO2/ZrO2 as an efficient reusable catalyst for the condensation of aromatic aldehydes, malononitrile, diethyl acetylene dicarboxylate and 3-chloro-4-fluoroaniline under green conditions. 3. A room-temperature synthesis of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates by the condensation of aromatic aldehydes, malononitrile, hydrazine hydrate and diethyl acetylene- dicarboxylate using Bi2O3/ZrO2 as a cost-effective catalyst with ethanol as a greener solvent. 4. Greener synthesis of indenopyrimidine derivatives by using Ag2O on ZrO2 as a recyclable catalyst for the one-pot condensation between an aromatic aldehyde, 1,3-indanedione and guanidinium hydrochloride at room temperature. 5. Synthesis of new 1,4-dihydropyridine derivatives via cyclo-condensation between an aromatic aldehyde, 1,3-cyclohexanedione, acetoacetanilide and ammonium acetate in an one-pot strategy through a green protocol using Fe2O3/ZrO2 as a reusable catalyst at room temperature. 6. A four-component fusion protocol for the synthesis of novel 1,4-dihydropyridine derivatives by the one-pot condensation between substituted aldehydes, ethyl acetoacetate,1,3-cyclohexadione/5,5-dimethyl-1,3-cyclohexanedione and ammonium acetate in ethanol. All the prepared catalytic materials were characterized by PXRD, TEM, SEM, Pyridine-IR and BET surface area analysis. All the synthesized organic compounds were characterized and confirmed by 1H NMR, 15N NMR, 13C NMR, FT-IR, single-crystal XRD, and HRMS. Advantages offered by these protocols are environmentally-friendly simple procedure, mild conditions and short reaction times with excellent yields.

Housing wealth is well established as one of the most important sources of wealth for households and investors. However, owning a home is a fundamental human need, making monitoring residential property prices a social endeavour as well as an economic one, especially under times of economic uncertainty. Residential property prices also have a direct effect on the macroeconomy because of how they influence wealth effects where increased consumption by households is experienced through gains in households balance sheets due to increased equity. Collecting correct and adequate data is vitally important in analysing property market movements and developments, particularly given globalization, and the interlinked nature of financial markets. Although measuring residential property price developments is an important economic and social activity, matching properties over time is extremely difficult because the sale of homes is typically infrequent, characteristics vary, and homes are uniquely located in space. This thesis focuses on appraising several residential property types located throughout South Africa from January 2013 to August 2017, investigating different modelling approaches with the aim of developing a residential property price index. Various methods exist to create residential property price indices, however, hedonic models have proven useful as a quality adjusted approach where pure price changes are measured and not simply changes in the composition of samples over time. Before fitting any models to appraise homes, an autoencoder was built to detect anomalous data, due to human error at the data entry stage. The autoencoder identified improbable data resulting in a final data set of 415 200 records, once duplicate records were identified and removed. This study first investigated generalised linear models as a candidate approach to appraise homes in South Africa which showed possible alternatives to the ubiquitous log linear model. Relaxing functional form assumptions and considering the nested locational structure of homes, hierarchical generalised linear models were considered as the next candidate method. Partitioning around the mediods was applied to find additional spatial groupings which were treated as random effects along with the suburb. The findings showed that the marginal utility of structural attributes was non-linear and smooth functions of covariates were an appropriate treatment. Furthermore, the use of random effects helped account for the spatial heterogeneity of homes through partial pooling. Finally, machine learning algorithms were investigated because of minimal assumptions about the data generating process and the possibility of complex non-linear and interaction effects. Random forests, gradient boosted machines and neural networks were adopted to fit these appraisal functions. The gradient boosted machines had the best goodness of fit, showing non-linear relationships between the structural characteristics of homes and listing prices. Partial dependence plots were able to quantify the marginal utility over the distributions of different structural characteristics. The results show that larger sized homes do not necessarily yield a premium and a diminished return is evident, similar to the results of the hierarchical generalised additive models. The variable importance plots showed that location was the most important predictor followed by the number of bathrooms and the size of a home. The gradient boosted machines achieved the lowest out of sample error and were used to develop the residential property price index. A chained, dual imputation Fisher index was applied to the gradient boosted machines showing nominal and real price developments at a country and provincial level. The chained, dual imputation Fisher index provided less noisy estimates than a simple median mix adjusted index. Although listing prices were used and not transacted prices, the trend was similar to the ABSA Global Property Guide. In order to make this research useful to property market participants, a web application was developed to show how the proposed methodology can be democratised by property portals and real estate agencies. The Listing Price Index Calculator was created to easily communicate the results through a front-end interface, showing how property portals and real estate agencies can leverage their data to aid sellers in determining listing prices to go to market with, help buyers obtain an average estimate of the home they wish to purchase and guide property market participants on price developments.

Accreditation in South Africa is a relatively new phenomenon compared to other countries. The United States of America have used accreditation for over a hundred years as a basis for quality assurance. This private, voluntary system of self-examination and peer review has been central to the creation of a U.S. higher education enterprise that is outstanding in many respects (Council for Higher Education Accreditation, 2013). Since the implementation of accreditation into the South African Quantity Surveying education system at Higher Education Institutes, it has promised numerous benefits with positive outcomes for universities and graduates. However, it has failed to convert these promises into a process that adequately prepares graduates that pass through the quantity surveying education programmes for the working world of the built environment industry. This investigation sought to discover the reasons why accreditation was not producing skilled graduates from accredited programmes in South Africa despite its claimed theoretical benefits. The research methodology adopted in this study was a quantitative approach. Two close ended well-structured questionnaires were developed and directed to a sample of quantity surveying graduates and built environment organisations who were actively practicing quantity surveying in Kwazulu-Natal. The purpose of the graduate questionnaire was to determine the opinions from graduates of quantity surveying programmes, their level of work readiness and the skills and competencies that they require for the world of work. The employer questionnaire identified the level of graduate quantity surveyors work readiness and the skills and competencies that they require for professional practice. Further investigations highlighted the responses of graduates from traditional universities and universities of technology, as well as male verse female comparisons. The findings of the study show that quantity surveying graduates were neutral about programme accreditation criterion and in it adequately preparing them for the world of work and professional practice. Employers agreed that students did not demonstrate a good balance of theoretical, practical and experiential knowledge. They were neutral about quantity surveying graduates and their level of work readiness from accredited quantity surveying programmes. They also regarded a combination of traditional, evolved and emerging skills and competencies as important for graduates to possess. The results indicate that the prescribed programme criterion for quantity surveying programmes do not align themselves with the expectations and needs of professional practice. Further findings indicate the SACQSP routes to registration requires students to graduate from accredited quantity surveying programmes. Only then can graduates professionally register and practice as professionals in society. However, it should be noted that most organizations (72.7%) did not require quantity surveying graduate employees to be registered with the SACQSP. A further analysis of quantity surveying graduates from traditional universities compared to universities of technology and male responses compared to female responses were conducted. The findings showed that there were no statistically significant differences between the them. To conclude, the current quantity surveying programmes offered by higher education institutes do not meet the requirements of the built environment industry by adequately preparing skilled quantity surveying graduates. The following recommendations were highlighted to assist in improving the current higher education quantity surveying programmes. These recommendations include an increased role and involvement of the built environment industry, collaboration between the SACQSP, higher education institutions and the built environment industry and future programme development.

Slope failure occurs due to various factors, one of the most significant being that of soil variability in a slope and associated geological threats such as unconsolidated soils, settlement, groundwater seepage and infiltration. The analysis of slope stability should incorporate and analyse the interactions between slope configuration, shear strength resistance, pore-water pressure and water conditions of a slope. This study focuses on the causal effects and slope stability of two natural slopes in Durban, KwaZulu-Natal. Large parts of the study area are underlain to great and varying depths by problem soils, namely the Berea Red Sands. These are dune soils, deposited by ancient wind activity, that are found parallel to the east coast of Durban. The Berea Red “sands” vary greatly in soil type ranging from fine grained sands to silts and clays. Those of looser consistency are known to undergo significant settlement under loading, and also with water interaction. The clay and silt varieties are known to exhibit heave under the same circumstances. In some cases, liquefaction of Berea sands may occur due to the loss of soil structure upon water introduction into the soil mass. The aim of this research is to formulate and compare the stability of the two slopes under different water conditions in the form of Factors of Safety and Probabilities of Failure, using RocScience© software. Site investigations were conducted to classify and collect soils, which were then put through rigorous laboratory testing. The results from testing were applied where possible to the modelling software and a host of important findings were made. The liquefaction potential of poorly graded, uniform Berea sands was observed first-hand on site, in the laboratory and again during slope stability analyses. As anticipated, the slope stability of both sites proved to increase reaching “optimum” conditions due to the positive effects of matric suction. Upon increasing water conditions further or saturating the slope, increasing incidences of failure and instability occurred due to the loss of matric suction and cohesion. This instability can also be attributed to the proven decrease in shear strength properties of the soil, cohesion and internal friction, leading to loss of shear strength in the slope. The positive effects of matric suction were further proven when the slope of Site A that considered matric suction (in the form of an air entry value), exhibited a slightly higher FOS and improved slope stability than the one without. The results and conclusions of this research project prove the importance of investigating a soils variability and the subsequent slope reaction under varying moisture conditions. These are key factors to consider prior to civil construction on problem soils, so as to mitigate major failures and the consequences thereof. Keywords: slope stability; soil variability; slope stability analysis; kinematic analysis; Factor of Safety; Probability of Failure; geotechnical design; applied geology; matric suction; soil shear strength; liquefaction potential; Berea Red sands.