Rare earth element (REE) in the surface sediments from Pahang River (28 samples) and Kelantan River (22 samples) in the eastern portion of Malay Peninsula are analyzed to decipher the characteristics of REE composition and distribution, to discern the controlling factors of REE composition, and to illustrate the significances of provenance tracing of REE. The results show that the total REE ranges from 24.88 μg/g to 304.29 μg/g, with an average of 165.22 μg/g, for the Pahang River; and 126.02 μg/g to 281.40 μg/g, with an average of 181.15 μg/g, for the Kelantan River, respectively. The UCC standardization of REE indicates that Pahang River sediments enrich with heavy rare earth elements, in relative to light rare earth elements. However, there is no significant difference between light and heavy rare earth elements in the Kelantan River. The composition of source rocks and minerals plays a controlling role in the REE composition of the two rivers. The influence of chemical weathering in the Pahang River is greater than Kelantan River, and the difference of grain size among the Pahang River sediments leads to larger REE variations. δEu_UCC-(Gd/Yb)_UCC discrimination diagram demonstrates that it can be used as an effective index to qualitatively seperate the sediment source of two rivers. It can further be used to trace and identify the source of sediments quantitatively on the continental shelf of Malay Peninsula.

The Weixi’nan Sag is the important research area of exploration and development integration. This study takes the Weizhou Formation of the No.2 Fracture Zone as the research object. By analyzing the geometry, kinematics, and dynamics characteristics of fracture, the "slope-flat" fault system in the middle section and the "shovel-type" fault system on both sides are divided into the level 3 en-echelon main fracture zone, the level 4 branch fracture zone, and the level 5 branch fracture zone. The "slope-flat" fault system in the middle section is subjected to higher in-situ stress, and the main and branch faults are more developed. The vast majority of oil and gas are distributed in the "slope-flat" fault system. A comprehensive analysis of the relationship between the internal fracture system of the differential fault system in the No.2 Fracture Zone and the oil-gas distribution law is made, and obtains the corresponding regular of 3 aspects of fracture reservoir controlling mechanism and 8 types of fracture reservoir controlling patterns. Under the regular of fracture reservoir controlling mechanism and patterns, the search and evaluation of targets are carried out around the inner or surrounding oil fields of the No.2 Fracture Zone, and good results are obtained. Based on the field production, the potential targets of North 1, North 3 and North 4 in the middle part of the No.2 Fracture Zone are searched and optimized. The three blocks have been successfully drilled, and the purpose of the geological reservoir has been achieved. The regular of fracture reservoir controlling mechanism and patterns which have been applied to the potential zone of the No.2 Fracture Zone in the southwest depression play very good effect.

By monitoring the typical profiles of the artificial cobble and sandy beach on Xiamen Tianquan Bay and Huizhan before and after the super Typhoon No.1614 Meranti, combined with the observation and numerical simulation of hydrodynamic factors, we calculate the wave field together with the total water level during the typhoon process, and analyze the morphology and the average variation of the profile. Results show that the characteristics of response to typhoon between artificial cobble and sandy beach on macro-tidal coast are significantly different. The majority of cobbles transported onshore, the beach face eroded while the beach berm accumulated to form a higher beach berm, and the slope of the artificial cobble beach is obviously steepened. In contract, the artificial sandy beach shows obvious sediment transport offshore, the upper beach face eroded and the lower beach face deposited, the slope of the beach face obviously become gentler, moreover the top of the beach berm become flattened due to the strong onshore wind after the typhoon landing, and the height of the beach berm almost remain unchanged. Whether the beach berm eroded during typhoon process is closely related to the total water level including astronomical tide, storm surge and wave run-up. During the process of typhoon, the artificial cobble beach characterized with higher wave energy and steeper beach slope showed less profile variation comparing to that of the artificial sandy beach. The artificial cobble beach performed a small degree of response to typhoon. Taken together, it is an effective approach of slowing sandy beach erosion by using gravels and other coarse-grained sediments for beach nourishment on strong eroded high-energy macro-tidal coasts.

Variation of pore pressure between soil particles, which caused by the cyclic loading from waves to seabed, is the main reason for soil liquefaction. By using a self-designed pore pressure monitoring equipment, we monitored pore pressure with a long-period, high-precision way in the easy-liquefied zone in Chengdao sea area of Yellow River Estuary. The monitoring results show that the maximum wave-affected depth is between 0.5 m to 1.5 m and no obvious pore pressure response in the deeper sediment during this period. Pore pressure variation in soil is mainly determined by tide level and wave height. Tide level changes can result in smooth change in pore pressure but can not cause the emergence of excess pore pressure while wave height changes can result in severe oscillation in pore pressure and lead to the appearance of excess pore pressure.

Comparison with Geophysical Model Function (GMF) developed by methods of empirical statistics, ocean microwave scattering model works well at all microwave frequency. Composite radar backscattering model is comprised of Bragg scattering model and geometrical optics model. We calculated the normalized radar cross sections (NRCSs) from the composite scattering model by using the sea surface wind speeds and directions measured by buoys moored in the northern of South China Sea in the whole year of 2014, and then compared them with SAR on board RADARSAT-2 at C-band, microwave scatterometer on board HY-2A satellite (HSCAT) at Ku-band, respectively. The biases of comparison are (–0.22±1.88) dB ( for SAR), (0.33±2.71) dB (for HSCAT in VV polarization) and (–1.35±2.88) dB (for HSCAT in HH polarization), respectively. We also calculated the NRCSs from the model by using the sea surface wind speeds and directions measured by NDBC buoys in the time period from October 1, 2011 to September 30, 2014, and then compared them with radar altimeter on board Jason-2 and HY-2A both at Ku-band with the bias of (1.01±1.15) dB and (1.12±1.29) dB, respectively. Although the biases of NRCSs between space-borne sensors and composite scattering model in medium and normal incidence are different each other, the accuracies of their sea surface wind speed products are the same(i.e. the root mean square errors are all less than 1.71 m/s). The results show that we can simulate the sea surface radar NRCSs of satellite-borne SAR, microwave scatterometer, and altimeter by using the composite radar backscattering model, and the simulations are consistent with that of CMOD5, NSCAT-2 and the GMF of operational wind retrieval for altimeter. It also indicates that the composite radar backscattering model could be used in calibration and validation of microwave sensors and simulation of radar backscatter from sea surface.

The tide gauge data provide an effective way to evaluate the accuracy of satellite altimeter data. The HY-2A data are filtered based on the data edited criterion and the model of real-time atmospheric pressure provided by NCEP are used to solve the problem caused by the unavailable dry tropospheric correction and inverse barometer correction in the later stage of the HY-2A exact repeat mission (ERM). By matching the HY-2A altimeter data and the tide gauges data in temporal and spatial, the correlation coefficient and standard deviation between the two kinds of altimeter data are calculated in the nine selected tide gauges area. According to the analysis results, the average correlation coefficient is about 0.676 9, the optimum is up to 0.898 7, and the average standard deviation is 0.089 5 m. The results show that the quality of HY-2A satellite altimetry data meet the design target and achieve the expected level. It provides a new reliable data source for the application research of the marine gravity field inversion.

Based on the ionospheric correction data of Global Ionospheric Map (GIM) and dual-frequency, extracting the Pacific Ocean dataset from the Jason-2 Altimeter’s Geophysical Data Set (GDR) including 38-period in 2015. The dataset is divided into small twelve cell according to the features of ionosphere over seasons and in latitude. The result shows that there is a significant difference between the GIM and the dual-frequency correction value, and the GIM correction value is generally higher than the dual-frequency correction value, indicating that GIM overestimates the ionosphere path delay, also, the difference between the GIM and the dual-frequency is related to the season and latitude. Applying the modified equation to the 2016 Jason-2 annual data, the corrected GIM value is very close to the dual-frequency correction value, and the applicability of the modified equation remains the same over time. In the case where the single-frequency altimeter cannot use the ionospheric dual-frequency correction algorithm, the GIM value of the altimeter of the same height can be corrected by using the correction equations of different quarters and different latitude regions to achieve the accuracy level of the dual-frequency correction value.

The spectral width of the electromagnetic scattering from sea surface is closely related to the SWH (significant wave height), and thus the spectral width can be used to retrieve the SWH. In this paper, the linear filtering method is employed to simulate the radial velocity of the orbit velocity of the each scattering element on sea surface. Based on the radial velocity, we establish a spectral width model, and analyze the influences of spatial resolution, time sampling length and SWH on spectral width. At the same time, we also discuss how to select the parameters such as time sampling length and the azimuth angle during the actual observation. Here, the theoretical results are compared with the estimated results based on the measured data required by the CSIR-X band radar. The comparisons demonstrate that the spectral width obtained by the estimation method based on Gaussian distribution standard deviation agree well with the theoretical results after eliminating the effects of radar noise and frequency leakage, which proves the reliability of the theoretical results. The results obtained in this paper have certain reference value for the retrieval of the SWH.