the province of Maria Trinidad Sanchez. Consists mainly of swamps with silt and clay, are also large areas of peat deposits. By the rivers are alluvial. Eastern Cibao Valley (Also part of the Cibao Valle). It is divided into the provinces of Santiago, Espaillat, Sánchez Ramírez, Sánchez and Duarte, the latter having a higher percentage (about 50%). All cities in this province are rooted in this valley except the city of Arenoso. The floodplains of the Yuna River system occupy a narrow strip on the south side of the valley and there is also a narrow chain of hills probably middle Miocene limestones adjacent to the North mountain range. For this province the valley also has marine lacustrine deposits of clay, basically of two kinds: a limestone and other no calcareous. The Haitises. They consist of a karst platform, which is composed of hard limestone from the Oligocene-Miocene. The highest elevations are generally tall. The Payabo River crosses the region by a narrow channel filled with alluvial deposits. Northern Range. It is a mountain range of sedimentary rocks and highly faulted and folded fobáceas. In this province the Northern Range reaches heights of (Quita Espuela); near San Francisco de Macorís the ridge height is slightly below . It presents some mudstone, limestone and Miocene and Eocene oligocénicos. To the south of Gaspar Hernandez and reaching the Nagua River there is a very complex area with rugged hills of limestone, tuff and probably with other volcanic and metamorphic rocks, mainly of Upper Cretaceous. Hydrography There are many rivers and streams in the Duarte Province, being the most important ones: the Camú River, the Yuna River and their tributaries (Jaya, Cuaba, Nigua, Payabo, among others). The Yuna River and Camú River constitute important sources of water, both for drinking as irrigation. Physiography and environment Environmental pollution in Duarte Province is the product of several elements such as the poor state of the latrines, untreated sewage, overflow of streams, indiscriminate use of agrochemicals, backwaters and installation of pigsties on the banks of rivers, as well as litter and some factories in the province that are thrown into rivers. Soil erosion from deforestation also affects the environment of the Duarte Province. Similarly, the smoke from factories and from burning trash, specifically in the municipality of San Francisco de Macoris, is affecting its inhabitants Climate Temperatures fluctuate between , with cooler temperatures affected by rainfall.