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A system for the detection of very low frequency (VLF) electromagnetic waves has been developed by Wuhan University (WHU) with the Polar Research Institute of China (PRIC), and has been successfully deployed by PRIC at the Great Wall Station (GWS, 62.22°S, 58.96°W) in Antarctica, as part of the Phase II of Chinese Meridian Project. The system has a dynamic range of ~110 dB and a timing accuracy of ~100 ns, and hence can provide observational data at sufficient resolution to contribute to space physics and space weather research. This paper reports initial measurements of the WHU VLF (Meridian Project-Phase II ID：OCHCH_WHWM01) wave detection system at GWS, to demonstrate performance of the system. Data from nearly one year of routine operation indicate that the system is effective in recording the dynamic change of ground-based VLF transmitter signals from North America and Europe. The characteristics of VLF transmitter signals observed at GWS during X-class solar flares are consistent with results from previous studies. The VLF data exhibited a good correlation in space and time with measurements of magnetospheric electron deposition during geomagnetic storms, as detected in the south Atlantic anomaly (SAA) region. The WHU VLF system additionally provides data on the wide-band whistler waves as excited by lightning discharge, the spectrum of which exhibits a distinctive dispersion structure. The unique position of GWS in Antarctica provides the opportunity to obtain observational data on VLF waves which can be used to investigate multiple aspects of space physics, including the propagation of whistler waves in polar regions, lower ionosphere disturbance, lightning discharge, and radiation belt electron precipitation from the radiation belts. These measurements are of critical importance in monitoring near-Earth space weather.

Electron diffusion caused by plasmaspheric hiss is an important mechanism for the loss of electrons in Earth's inner magnetosphere; it has also been considered responsible for the formation of the slot region between inner and outer radiation belts. The cold plasma dispersion relation of plasmaspheric hiss is widely used to quantify the scattering effect of energetic electrons. However, the existence of hot plasma in a realistic magnetospheric plasma environment modifies the dispersion relation of plasmaspheric hiss, thereby affecting wave-induced energetic electron scattering. This paper presents the results of some recent studies on the influence of hot plasma on the dispersion relation and electron scattering effects of plasmaspheric hiss. Using statistical analysis results based on satellite wave observations, the modification of the hiss dispersion relation under the effects of hot plasma was verified. Furthermore, based on typical case analyses and numerical calculations using the quasi-linear diffusion theory, we investigated the dependence of the hiss-driven electron scattering rates on the geomagnetic activities and hot plasma parameters (i.e., temperature anisotropy, hot electron temperature, and hot electron abundance). The results revealed that the cold plasma dispersion relation overestimates the scattering rate of energetic electrons below 100 keV. For electrons above 100 keV, the differences between the cold plasma and hot plasma dispersion relations in terms of the induced scattering rates are somewhat smaller; this indicates that using the cold plasma dispersion relation can lead to the underestimation of the hiss-driven rates of electron pitch angle diffusion at smaller pitch angles and the overestimation of the rates at higher pitch angles. In addition, the cold plasma assumption can cause resonant diffusion down to lower electron energies; however, when the observed hiss wave dispersion curves are used, the resonant electron diffusion tends to extend to smaller pitch angles with a broader range. Notably, the differences in the scattering rates between the cold plasma and hot plasma dispersion relations increase with the hot plasma parameters. Therefore, our results are important for future simulations of the hiss wave-induced electron diffusion processes in the actual magnetospheric plasma environment and the dynamic variability of radiation belt electrons.

The integrated analyses, classification and comparison of petroleum systems, combined with the latest oil and gas field data from the Middle East and the previous research results, indicate how tectonic-depositional evolution, source rocks and seals, and petroleum resource endowment are inter-linked. The impacts of these factors on the enrichment of petroleum resources could be established. There are four super petroleum systems in the passive margin basins of the Arabian Plate, namely, the intra-craton, the back-arc, the passive margin and the active margin, among which the passive margin and intra-craton super petroleum systems are the most significant. Regionally, oil and gas in the study area are mainly concentrated in the Central Arabian Basin and the Rub' Al Khali Basin. Stratigraphically, oil is mainly reservoired in the Cretaceous and Jurassic whereas the gas in the Permian and Triassic. The diffe-rential enrichment of hydrocarbons is mainly controlled by three factors: the distribution of high-quality effective source rocks and the positive structural trends of basins, which have a dominant control on the regional distribution of oil and gas, and the regional seals, which govern the stratigraphic distribution of oil and gas.