Особенности тектоники территории Гомеля в связи с оценкой устойчивости геологической среды

Abstract

B статье рассматриваются особенности тектоники территории Ãомеля. По результатам исследований в пределах города установлена серия тектонически активных разрывных нарушений различного ранга, формирующих блоковую структуру фундамента и нижней части осадочного чехла. Обращается внимание на влияние тектонических факторов на орографические условия и проявление современных геологических и инженерно-геологических процессов и явлений в пределах Гомеля. B работе указывается на необходимость учета тектоники при комплексной оценке устойчивости геологической среды территории городов. нальный разлом субмеридионального простирания отделяет ее от Северо-Припятского плеча, на юго-западе Северо-Припятский суперрегиональный разлом–от Припятского грабена, с юго-востока ступень отделена от Гремячского погребенного выступа Лоевским региональным разломом. Так как региональные разломы картируются в пределах города, т. е. территории интенсивной застройки, актуальной является задача точного определения местоположения разломов и их активности. В пределах Гомеля планомерная геолого-геофизическая информация отсутствует. О сложности геологического строения наиболее достоверно можно судить по пробуренным скважинам на минеральные воды, а также по геофизическим, геодезическим, геоморфологическим и другим данным. The article describes some tectonic features peculiar to the territory near Gomel. Investigations carried out within the town revealed a series of tectonicly active rupture dislocations that are responsible for the block structure of the basement and lower part of the sedimentary cover. It was determined that the basement faults shift slightly as a rule the lower sedimentary strata. Most of dislocations are manifested in the modern landscape by overlying zones of scattered, nonaffine and repeated deformations and abnormally high fissuring, deconsolidation and changes in the composition of the basement and sedimentary cover rocks. Anomalies of different types are peculiar to faults: structural, gas-conductivity, geochemical and geophysical field anomalies, etc. The revealed geodynamicly active zones are areas of high geoecological hazard. Investigations have shown that the local and areal severe natural and industrial changes of the geological environment are confined to the above zones. Ex. gr, rapid transitions of valleys to the gullies and ravines, and then to rivers are peculiar to recent tectonic uplifts. The valley pattern sometimes begins with a gully. Within tectonic lows the drainage valleys are usually replaced by gullies. The similar picture is observed in the central part of the town distinguished as a local uplift, where the valley network begins with gullies. In the northern part of the territory within a tectonic low the erosion drainage valleys are replaced by large ravines with gently sloping sides. Within the town area which experiences uplifting nowadays, an asymmetry of the Sozh river valley is evident without an asymmetry of the watershed area. So, in the northern and southern parts of the town the Sozh river valley is symmetrical, but in the central part it shows an asymmetrical character as its right bank is erosional. Within the territory of the town the eolian and bogging processes are very intensive and their operation depends on recent tectonic movements. The tectonicly active zones revealed within the town of Gomel have been used for a large-scale division of the studied territory into engineering and geological zones with respect to the geological environment stability to technogenic loads, and for forecasting future engineering and geological processes and phenomena which may be used to elaborate the nature protection measures and optimal alternative designs of new buildings and reconstruction of engineering structures. The data obtained suggest a necessity of tectonic features to be considered when a complex assessment of the geological environment stability to the technogenic loads in urban territories is carried out.