Geomagnetic field mapping

This work focuses on creating maps of the geomagnetic field and areas of increased cosmic radiation surrounding the Earth. Data were measured by Proba-V satellite at Low-Earth orbit 820 kilometres above the Earth during 2015. The actual measured data were compared with the calculated magnetic values. The created maps serve to a better understanding of the shape of the geomagnetic field and show magnetic equator, north magnetic pole and more. The map confirms that the area of the South Atlantic Anomaly corresponds with the weakest area of the geomagnetic field. Maps of different time periods of 2015 show small changes in the shape of the geomagnetic field during a year. Increased attention was paid to June 2015, when solar flares were passing near the Earth. The observation confirms that solar flares have a significant effect on the shape of the geomagnetic field.

Retrieving paleopoles using newly mapped lunar magnetic anomalies within basins

<p>Orbital spacecraft magnetic field observations show that several isolated magnetic anomalies are found to be heterogeneously distributed over the lunar surface. The magnetic anomalies origin is still debated; however, it is largely accepted that an ambient core magnetic field was present during their formation. Contrary to previous studies, here we focus only on anomalies that are related to basins/craters, which correspond to the best possibility to hold ancient core field information. In particular, the basin rocks become thermoremanently magnetized as the melt sheet cools down slowly recording the ambient magnetic field that was present when the crater was formed.</p><p>We build regional magnetic field maps using data from quiet orbits of Lunar Prospector and Kaguya spacecraft. When comparing these regional maps to existing global models, several differences and details are discovered. Further investigation is required to understand why small scales are missing from global models. For each mapped crater, we perform inversions for the magnetization direction to estimate the corresponding paleopole position (defined as the north magnetic pole when the anomaly formed). In detail, a grid of dipoles is placed over the basin inner depression, where the melt sheet is believed to be. All dipoles have the same common direction, nonetheless different dipole moments.</p><p>Preliminary results show that paleopole positions of regionally mapped anomalies associated with craters are not in absolute agreement with previous paleopole studies. Also of significance is the distribution of dipoles obtained, which seem to be consistent with inferred impactor trajectories. We conclude that paleopole position results are highly dependent on the technique and choices we make to construct the magnetic field maps. Further studies of several other craters will be performed, but we expect large differences when using regionally mapped anomalies. Our results will help to better constrain the lunar ancient core field morphology.</p>

Moving daily average of the hourly magnetic field values - the example of usage at Novosibirsk Observatory during 2011 (results and prospects)

The parameters of the equivalent central dipole calculated using hourly values of the magnetic field elements during 2011: the angular elements transformed to the hourly values of the geographic coordinates of the North magnetic pole and the intensity values transformed to local magnetic constant. Next step is the calculation of the daily mean values at every hour. This method applied to both current digital data and historical data presented as monthly tables of hourly values. The advantage of method is its ability to show the changes of the magnetic field independently from daily variation. Using of the “integrate” parameters (the magnetic pole coordinates and local magneto constant) allows detect the regional features of its variations. The features in the daily values compared with anomalous geological and geophysical events observed in the past and predicted in the near future.

AS FOLLOWS FROM OUR MODEL THE NORTH MAGNETIC POLE IS STABLE IN ITS DRIFT

Северный магнитный полюс движется согласно модели дрейфа, предложенной канадским магнитологом Хоупом 1 и разработанной автором этой статьи 2, 3. В основе модели участие двух глобальных магнитных аномалий (ГМА): Канадской (КМА) и Сибирской (СМА). Вблизи этих ГМА расположены магнитные обсерватории: РезольютБей (RB Resolute Bay) в Канаде и Мыс Челюскин (CCh Cape Chelyskin) в России. Обсерватории регистрируют изменения величин Нкомпонент модуля геомагнитного поля (ГМП), причем в настоящее время в Канадском секторе регистрируется увеличение модуля ГМП, а в Сибирском, его уменьшение. Точка, в которой направленные навстречу векторы Нкомпонент равны друг другу, а Нкомпонента равна нулю, и есть СМП. Скорость дрейфа СМП определяется скоростью увеличения (или уменьшения) величин соответствующих ГМА. Использование этой простейшей схемы позволило автору давать очень точные прогнозы мест расположения СМП. Точно так же было определено время перехода СМП из Западного полушария в Восточное (лето 2019). Точность методики определяется исключительно точностью аппроксимации величины Нкомпонент 24. The North Magnetic Pole submits its moving to the drift model proposed by Canadian magnitologist Hope 5 and this developed by the author 6,7 which suggests an impact of two global magnetic anomalies (GMA), Canadian (CMA) and Siberian (SMA) into the pole drift. Magnetic observatories Resolute Bay, Canada, and Cape Chelyskin, Russia, located near these GMA, are recording the Hcomponent values. Nowadays increasing at the Canada area the geomagnetic field module is decreasing at the Siberia one. The NMP is the point where the vectors of Hcomponent directed towards each other are equal and the value of Hcomponent makes zero. The velocity of the NMP drift is determined by the fluctuating rate of GMA magnitudes. This technique enabled the author to predict as the NMP positions and the time of the NMP transit from the West hemisphere to the East one as 2019, summer. The technique accuracy is governed by accuracy of Hcomponent values approximation 6, 7, 13.

Edge Detectors as Structural Imaging Tools Using Aeromagnetic Data: A Case Study of Sohag Area, Egypt

The present study was designed to give a clear and comprehensive understanding of the structural situation in the Sohag region and surrounding area by applying several edge detectors to aeromagnetic data. In this research, the International Geomagnetic Reference Field (IGRF) values were removed from the aeromagnetic data and the data obtained were then reduced to the north magnetic pole (RTP). A combination of different edge detectors was applied to determine the boundaries of the magnetic sources. A good correlation was noticed between these techniques, indicating that their integration can contribute to delineating the structural framework of the area. Consequently, a detailed structural map based on the results was constructed. Generally, E-W, N45-60E, and N15-30W directions represent the main tectonic trends in the survey area. The structural map shows the existence of two main basins constituting the most probable places for hydrocarbon accumulation. The results of this study provide structural information that can constitute an invaluable contribution to the gas and oil exploration process in this promising area. They show also that the decision in choosing the location of the drilled boreholes (Balyana-1 and Gerga) was incorrect, as they were drilled in localities within an area of a thin sedimentary cover.