Geophysical Survey

About: Geophysical Survey is a facility organization based out in Obninsk, Russia. It is known for research contribution in the topics: Geology & Fault (geology). The organization has 308 authors who have published 256 publications receiving 3067 citations. The organization is also known as: Federal State Institution of Science Geophysical Survey of the Siberian Branch of the Russian Academy of Sciences.

Mapping subsidence in Tianjin area using ASAR images based on PS technique

Abstract: By identifying temporarily stable natural reflectors or persistent scatterers (PS), PSInSAR (Persistent Scatterers for SAR Interferometry) technique can analyze this subset of pixels in SAR images, even with long temporal and space baselines, to get high accuracy deformation measurements. We implement the PSInSAR process that is briefly summarized in this paper and apply this method in Tianjin area to detect the deformation phenomena using ENVISAT ASAR images. Calibration of ASAR images helps us select more PSC and using calibrated backscattering coefficient threshold we can discard the pixels whose amplitude are relatively stable while whose backscattered signals are weak and incoherent. Results obtained by processing 14 images show the distribution and the relative deformation value of the displacement field. The estimated linear velocities of PS are not accurate enough because of the relatively small number of images.

Geological Evidences of the Deformation in Central-Southern Ningxia in the Miocene and Its Significance

Abstract: By analyzing the regional distribution of unconformity in Cenozoic strata and their sedimentary characteristics we found that there were at least two tectonic events affecting central-southern Ningxia during the Miocene, one in the Early Miocene, the other in the late Middle Miocene, and the later one was much stronger and more widespread than the former one. The former one was found to the west of the Liupan Mountain, and the later mainly occurred along the Chahanbulage-Sanguankou-Qingtongxia-Guyuan (Cha-Gu) fault. Most the Hongliugou Formation in central-northern Ningxia was deposited under stronger tectonism in the Miocene. The tectonic event in the early Miocene mainly distributed to the west of the Liupan Mountain including eastern Gansu, and this event resulted in the deformation of the Qingshuiying Formation and the unconformity between the Hongliugou Formation and Qingshuiying Formation. Because most of these phenomena were distributed along the Haiyuan fault and adjacent areas, we conjecture that the Haiyuan fault may be active in the early Miocene. And the event in late Middle Miocene had shown its existence in the following aspects, in the west of the southern Helan Mountain the thrusting taking place in the late Middle Miocene has been found, thick syntectonic sediments, Hongliugou Formation was deposited, the unconformity between the Hongliugou Formation and Qingshuiying Formation because of the tectonism in late Middle Miocene along the Cha-Gu fault was also found, the Hongliugou Formation in these areas also deposited at the same time, which means that during that time the deformation front of the Qinghai-Tibetan plateau had extended to the Cha-Gu fault, i.e. the western margin of the Ordos basin, the early Cenozoic basin was dismembered in this event; and at the same time the Hongliugou Formation in the basin became coarser and coarser upwards which also means that in the late Middle Miocene one stronger tectonic event had affected this region. This event led to the uplifting of the Xiang Mountain, which dismembered the former basin to small piggy-back basins. Undergoing these two tectonic events, central-southern Ningxia had been incorporated into the thrust wedge of the northeastern Qinghai-Tibetan plateau, and the reason for this thrust wedge extending to the northeast may be the remarkable uplifting of the northern part of Plateau at the same time which resulted in the taper angle of the wedge over the critical value and made it spread forwards. The Cha-Gu fault was once similar to the present Haiyuan fault as the deformation front, and the development of the whole of northeastern plateau was not forward-breaking, but expended with out-of-sequence. The above phenomena are not consistent with the viewpoint of former workers that the deformation of Cenozoic strata in Ningxia occurred since the end of the Pliocene.

Magnetic Field Detector and Ground-Penetrating Radar Device with Merged Display

Abstract: In an embodiment of the disclosed technology, a visual output of data from a ground-penetrating radar and magnetic field measuring device is displayed on a visual medium. The display has a first exhibition of output from the ground-penetrating radar device and a second from a magnetic field measuring device, such as a very low frequency (VLF) receiver. Using an identical axis, such as an X-axis measuring time or distance, output of each device is exhibited and overlaid over one another. In this manner, one can detect (using two different methodologies and uses) the visual exhibition of both to best determine the location of a metal or electrical target.

Generalized Play-Operator Under Stochastic Perturbations: An Analytic Approach

Abstract: A new class of models of hysteretic converters which generalizes the classical play-operator with stochastic properties (defining curves of this operator are treated as non-deterministic and have a random distribution) is proposed. In this case an output of stochastic converter is defined as a random process. The correctness of the definition of the corresponding converter in terms of a special limit construction is proved. Within this definition an output of the corresponding converter is determined at arbitrary continuous inputs. Properties of introduced converters are investigated and illustrative examples are presented.

The mean height and hypsographic curve for New Zealand

Abstract: The mean height of New Zealand is found to be 483 m, that of the North Island 298 m, and of the South Island 627 m. Of the total area of 2·,074 × 106 km2 of the New Zealand continental block, bounded by the 2,000 m depth contour and including the Campbell Plateau, Chatham Rise, and part of the Lord Howe Rise, only 14 per cent rises above sea level, a further 12 per cent being continental shelf less than 200 m deep. The hypsographic curve for the New Zealand continental block suggests that the predominant continental level lies about 1 km lower than the world average, giving New Zealand the appearance of a low-lying continent with only its mountain ranges appearing above sea level. Tables are given of the area, volume, centroids of area and volume, mass, and gravitational potential energy of land above a series of base levels 200 m part down to 2 km below sea level.