Structure of the sedimentary cover of the island Aleksandra's Earth of the archipelago of Franz Joseph land

Aim. To investigate the structure of the sedimentary cover Cape "Nagurskoe" about. Alexandra Arch. Franz Josef (Franz Josef Land) for microseisms measurements on the two profiles, passed during expeditions of 2011-2012. Methods. The technique involves the preparation of microseisms measurements of their relative intensity distribution along the profile and depth using the microseismic sounding method (MSM). To minimize the distorting influence due to the random nature of microseismic field, carried signal accumulation and rejection records unfit for processing the spectral characteristics and waveforms. Results. Analysis chart data processing microseisms measurements on two profiles allows the following conclusions. First of all, that the upper part of the Earth's crust (sedimentary cover) is heterogeneous, it includes a number of disorders of different genesis. Low speed zones shown in the diagrams represent the structure stretching presumably due pop superplume. Stretching crustal structures accompanied by penetration through attenuated area of dolerite bodies and other magmatic material. In this low-velocity zones within the sedimentary layers are likely to be a reflection of bitumonakopleniya. In particular, some low-velocity zones are similar in configuration to "trap" a substance with a low density. The anomalous zone is the western part of the diagram of the first profile, expressed broad band high-velocity section, extending from a depth of 2,000 meters to the surface of the sedimentary cover, possibly due to the presence of dike type intrusions and other volcanic rocks. On the same diagram is visible within the distance from 500 to 1100 m, sloping and permeates the entire sedimentary cover (from the surface to 2000 m) pronounced low-velocity zone, representing, in all likelihood, any fault or violation. This is indirectly confirmed by drilling "Nagurskaya" identified a number of refractors in the sedimentary cover, for example, a pronounced difference in velocity at depths of 0.5 and 1.3 km long and less pronounced - at depths of 1.0 and 2.2 km. Scientific novelty. For the first time in the territory of the Arctic zone of the Russian Federation carried out raying the structure of the sedimentary cover by microseismic sensing. Obtain detailed information on the structure of the sedimentary cover Cape "Nagurskoe" about. Alexandra, confirms the results of geological and geophysical surveys, prior to the architect. Franz Josef, in particular, and in this area, suggesting a possible method of MSM receive adequate understanding of the structure of the crust in the Arctic territories. The practical significance. Sounding of the sedimentary cover of the earth's crust, conducted in small profiles on the Cape "Nagurskoe" allowed to get a fairly clear picture of the structure of the upper crust of the site, indicating the possibility of identifying anomalies and geological environment over large areas. With a further, wider front expeditions appear to conduct seismic mapping of all areas, including the Arctic region.