GNSS technology has made great contributions to the development of surveying and mapping in Vietnam. Many useful GNSS processing software packages have been created and widely used all over the world. However, since these software programs only have input and output, the new users without expert theoretical knowledge (especially new students) can not understand the principle or interfere with the process to obtain explicit results at each step. Therefore, the research team has built the GNSS-HUMGAdj software package to visually illustrate GNSS data processing steps for students to use. In the design stage, the group has learnt the experience in programming GNSS processing software, inheriting published GNSS data processing algorithms. In addition, some algorithms such as converted GNSS baseline in resolving the relative positioning problem, adjusting the receiver antenna height, and the effect caused by the change of distance over time were developed in the software.

In northeastern Vietnam, the Khau Loc zone is considered to have high potential for lead-zinc mineralization. The lead isotope data for 18 galena samples and 18 ones of δ34S isotope data (including galena and pyrite samples) were collected from lead-zinc ore deposits in some areas in the Khau Loc zone, including Phia Dam, Khuoi Man, Ban Lin, Lung Dam, and Ta Pan. These were employed to investigate the sulfur and lead isotope geochemical characteristics of Pb-Zn deposits and their significance in this study. The samples were analyzed using the LA-ICP-MS to show that the Pb isotopic ratios of 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb in the galena samples range from 17.8908 to 18.6012, 15.5794 to 16.1025, 38.4420 to 39.2118, with the average values of 18.296, 15.749, and 38.812, respectively. The pyrite and galena samples had the δ34S isotope, ranging from 9.0 to 15.106. The sulfur isotope systematics implies that most of the lead-zinc ore formations originated from marine sedimentary evaporation deposits and magmatic intrusion-volcanic eruption sources rich in silica. The distribution of lead isotopic ratios had a well-defined cluster for each deposit, indicating the formation of lead-zinc deposits and lower crust and orogen trends. In addition, these findings of lead isotopic ratios and δ 34S isotopes proved that the Khau Loc zone is an activated structure with continuous growth in continental crust thickness during the early Proterozoic and Cenozoic periods. Furthermore, the study results also presented the evolution of material sources involved in the formation of lead-zinc ores in the Khau Loc zone.