{"id":239,"date":"2012-03-28T17:40:08","date_gmt":"2012-03-28T13:40:08","guid":{"rendered":"https:\/\/www.zond-geo.co\/english\/?page_id=239"},"modified":"2018-10-28T20:56:33","modified_gmt":"2018-10-28T16:56:33","slug":"zondst2d","status":"publish","type":"page","link":"https:\/\/www.zond-geo.co\/english\/zond-software\/seismic-tomography\/zondst2d\/","title":{"rendered":"ZondST2D"},"content":{"rendered":"ZondST2d<\/strong> is designed \u00a0for two-dimensional interpretation of seismic tomography<\/strong>\u00a0data on refracted and reflected waves (land, cross-borehole and water variants).\r\n\r\nThe software includes the following modules: 1. MASW\/ReMi<\/a> – surface waves data processing and interpretation, 2. Refraction waves forward modeling and inversion in arbitrary layered medium , 3. attenuation tomography<\/a>, 4. velocity anisotropy, 5. Reflection waves forward modeling and inversion<\/a> in arbitrary layered medium.\r\n

In geophysics,\u00a0the term\u00a0seismic tomography<\/strong>\u00a0is known\u00a0for a long time.\u00a0This is due to\u00a0the fact that one\u00a0of the main problems in\u00a0seismology\u00a0–\u00a0the inverse\u00a0kinematics.\u00a0It consists in determining the\u00a0velocity structure at\u00a0a known\u00a0time\u00a0path of the refracted waves\u00a0from \u00a0source to receiver. \u00a0The most popular\u00a0in engineering\u00a0geophysics\u00a0was\u00a0crosshole Seismotomography.\u00a0This direction is used\u00a0for detailed\u00a0studies of \u00a0rocks\u00a0velocity structure \u00a0in the interborehole space.<\/p>\r\nZondST2d<\/strong> represents ready solution for seismic tomography<\/strong>, and solves wide range of problems from mathematical modeling and quality control to field data processing and interpretation. Convenient interface and variety of data visualization features allow to solve wide range of geological problems with maximum effectiveness.\r\n

\"First<\/a><\/p>\r\nThe software consists of two basic modules. One for the first times picking on the seismograms. The second is used for solving forward and inverse problems of seismic tomography.\r\n

\"MASW<\/a><\/p>\r\nFor the seismograms processing developed a special interface designed to simplify and automate the process of first arrivals times picking<\/a>. Special attention is paid to variety ways of data visualization and simple access to frequently used functions.\r\n

\"MASW<\/a><\/p>\r\nSolution of forward problem basis on special ray tracing algorithm of graph theory (Shortest path’s method). This algorithm is characterized by a high-speed calculations, and controlled accuracy.\r\n\r\nZondST2d<\/strong> uses simple and clear data format which allows easily combining various systems of observation, including different variants of the topography setting up and other additional information.\r\n\r\nImportant stage which prevents field measurement is mathematical modeling of velocity structure<\/a> for seismic tomography<\/strong> survey. Modeling gives a chance to estimate the level of reflected waves first times and to make a choice of optimum parameters of the observation system for decision of formulated geological problem. ZondSt2d<\/strong> has great range of tools for mathematical modeling and analysis of refracted and reflected waves.\r\n

\"Layered<\/a><\/p>\r\nAs the general task of the program is inversion of velocity parameters, some variants of seismic tomography<\/strong> inverse problem solutions are designed\u00a0in ZondST2d<\/strong>, basic of them are: smoothing inversion \u2013 to get smooth model and focusing – to get \u00a0piece-smoothed model of velocities with depth.\r\n

\"Attenuation<\/a><\/p>\r\nWhile program was designed special consideration given to a priori data accounting. Because of equivalence of inverse geophysical problems, quality of the obtained results strongly depends on the amount of a priori data\u00a0used. In ZondST2d<\/strong> there is possibility of weights setting for measurements, fixing and limits making of changing features of different cells, using of a priori model as reference \u00a0in inversion. The robust schemas of noise estimation\u00a0are designed\u00a0in the software. There is also possibility to import and display results of measurements by other methods and boreholes data that improved quality of results.\r\n

\"Velocity<\/a><\/p>\r\nBasic features:\r\n