Телекоммуникационные системы для мониторинга и охраны лесных ресурсов России

Излагаются результаты разработки и полномасштабного внедрения телекоммуникационных систем семейства "Ясень" для мониторинга и охраны лесных ресурсов России, составляющих более четверти ресурсов мира. Описаны модификации систем семейства "Ясень" для федерального, регионального уровней и для подразделений, в которых предусмотрена интеграция каналов связи (наземных, радио, сотовых, спутниковых), документированная связь, геоинформационный мониторинг и сопровождение подвижных объектов

Characterization of an Upper Permian tight aas reservoir : a multidisciplinary, multiscale analysis from the Rotliegend, Northern Germany

This thesis describes a multidisciplinary, multiscale approach to the analysis of tight gas reservoirs. It focused initially on the facies architecture of a Permian tight gas field in the Southern Permian Basin (SPB), East Frisia, Northern Germany. To improve field development, 3D seismic data, wireline and core data were compared to a reservoir analogue in the Panamint Valley, California, United States. Depositional environments of the Permian Upper Rotliegend II included perennial saline lakes, coastal parallel sand belts comprising wet, damp and dry sandflats and aeolian dunes with interdune deposits. Polygonal patterns at different scales were observed on seismic horizon slices in the reservoir intervals and the overlying Zechstein. Outlines of superordinate polygons coincide with interpreted faults. Similar polygonal networks were identified on satellite images of modern dry lakes in the western United States. The mega-crack pattern of ephemeral dry North Panamint Lake, United States, is characterized by variably sized polygons with diameters ranging from kilometres to metres. The evolution and subsurface extent of this polygonal pattern and a potential tectonic link was examined by ground resistivity measurements and surface mapping. Crack development is initiated by shrinking of clays due to changes in water content in the near surface range. For crack evolution the following processes are proposed: Cavities develop in ~1m (3ft) depth during a subsurface phase, followed by an upward progression and the evolution of the actual surface cracks with the collapse of the overburden into the existing cavities. Cracks are filled by wind-blown sand and dried-out lake sediments from collapsing crack walls. Following burial, differences in competence between crack-fill and surrounding playa lake sediments provide zones of structural weakness that might channelize stress release and faulting. Ground resistivity measurements confirmed the extent of the cracks to a depth of more than 3 m (9 ft). The maximum horizontal influence area expressed by increased moisture contents on the playa surface is up to 12 m (36 ft). Such fissures systems may develop into weakness zones that serve as fault grain and impact reservoir quality in terms of hydraulic connectivity of reservoir compartments. For the Rotliegend reservoirs, porosity and permeability in the reservoir interval was inverted/decreased by cementation along migration pathways during diagenesis. Permeability barriers and compartmentalised reservoirs are a potential result of this development. In addition to the large scale approach analysing seismic data on the regional and reservoir dimension, a workflow that investigates microporosity by combining Scanning Electron Microscopy-Broad Ion Beam (SEM-BIB) and optical microscopy was developed. The SEM-BIB technique displays pores down to nm-scale on polished surfaces (~area of 1.5 mm2). The ion beam preparation thus provides unprecedented insights into pore geometries and morphologies of tight rock formations in general. As a result, a relative timing of crystallization was established and multiple phases of clay mineral growth identified. Furthermore, the study focused on pore orientation analysis and stress indicator identification using image analysis as a tool. As a first step, a workflow for an upscaling from the SEM images to thin sections was developed. For a better understanding of the depositional environment and reservoir rock distribution in the SPB, a sedimentary facies analysis of four cores from the tight gas field in East Frisia was compared to a second study area in northern central Germany. The focus lay on a comparison of the depositional environments and palaeo-geographic positions in the SPB during the Upper Rotliegend II (Upper Permian). In contrast to the tight gas field, which was located at a marginal position of the SPB, the second interest area was situated closer to the great saline lake at the centre of the SPB. While the sedimentation was dominated by dry aeolian sediments in East Frisia, deposition in northern central Germany mainly took place under sub-aquatic conditions. The lake level changes of the Rotliegend lake are expressed as cyclicity in the sediments of the cores. This study demonstrates that tight gas exploration and production requires multidisciplinary, multiscale approaches beyond standard seismic interpretation workflows to better understand the temporal and spatial evolution of these complex reservoirs