An example supporting the Core and Periphery Model is Brazil. The 'golden triangle' at the core is composed of Rio de Janeiro, Iguazu Falls and Buenos Aires, whereas the main peripheral area is the Amazon Rainforest. Overheating causes severe problems here because many people move from the periphery into the core in search of better economic opportunities/QOL etc. This can lead to lack of housing and the creation of favelas, especially in cities such as Sao Paulo and Belo Horizonte.