Quantifying organic carbon storage and sources in sediments of Dong Rui mangrove forests, Tien Yen district, Quang Ninh province using carbon stable isotopeThe present study showed that the fine sediment grained size fractions (< 63 µm) varied in a large range from 8.58 to 82.10%, and TOC and TN contents ranged from 0.21 to 10.20% and 0.01 to 0.34%, respectively. The TOC and TN contents tended to decrease with sediment depth and the fine sediment grained size fractions. The total OC storage in ...
10 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 621 | Lượt tải: 0
Preliminary assessments of debris flow hazard in relation to geological environment changes in mountainous regions, North VietnamDebris flows are disastrous that are difficult to predict due to forming condition localized and complicated. This is the main difficulty in warning and zoning forecast. Debris flows in northern mountainous regions of Vietnam occur mainly in the proluvial and colluvial deposits or tectonic breccia zones. These soil-rocks mixed masses are we...
10 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 1894 | Lượt tải: 0
Some study results of Cam Ranh - Binh Thuan mud eruption stripWith regards to the origin of erupted mud material: clay mud is not deep level-derived (in the deep lithosphere layer), but is from shallow part in the crust. The mud contains alkaline bentonite clay formed in a tectonic subsidence zone. The origin of this clay mud is formed by chemical weathering and hydrolysis processes of alkali-rich mine...
21 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 849 | Lượt tải: 0
Magma source feature and eruption age of volcanic rocks in the Tram Tau district, Tu Le BasinThe Sr and Nd isotopic compositions of volcanic rocks in the Tram Tau district (and Tu Le basin, in general) are highly enriched for a mantle source, suggesting involvement of crustal melts. To produce magmatic melts having 87Sr/86Sr ratio from 0.7058 to 0.7094, a mantle-derived melt with strontium isotopic ratio of 0.703 has to mix with cru...
14 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 715 | Lượt tải: 0
Algorithm and program for earthquake prediction based on the geological, geophysical, geomorphological and seismic datanew algorithm and a maximum earthquake prediction program according to geological, geophysical, geomorphological and seismic data have been established. The program includes a system of windows, enabling the selection and addition of different parameters characterizing the seismogenic possibility of the Earth’s crust. The program allows not ...
11 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 681 | Lượt tải: 0
Seawater desalination using air gap membrane distillation – an experimental study on membrane scaling and cleaningAGMD of an actual seawater feed were investigated. The experimental results demonstrate a profound influence of feed salinity and operating temperature on water flux, scaling behavior, and the efficiency of subsequent membrane cleaning. Feed salinity reduced the water flux of the AGMD process with seawater compared to that with fresh water, part...
8 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 651 | Lượt tải: 0
Characteristics of marine environmental geochemistry from Ha Tinh to Quang Nam (60-100 m water depth)Seawater is characterized by alkaline-weak oxidation and less effect by flows and activities from main lands and mainly contained of organic biodegradable materials. Surficial sediments of Ha Tinh - Quang Nam Sea (60-100 m in water depth) contained fineto coarse- grained size fractions. In which, the sediments with high absorbed capacity to ...
14 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 703 | Lượt tải: 0
Assessment of geomorphic processes and active tectonics in Con Voi mountain range area (Northern Vietnam) using the hypsometric curve analysis methodThe hypsometric curves and its statistical moments are useful tools to assess the geomorphological processes and recent tectonic activity of the region as well as the comparison between different zones. The Day Nui Con Voi area has revealed 3 curves such as "straight- shape", "S- shape", and concave curves. The concave curve is the most commo...
15 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 869 | Lượt tải: 0
Probabilistic seismic hazard assessment for the Tranh River hydropower plant No2 site, Quang Nam provinceIn this paper, the results of probabilistic seismic hazard assessment (PSHA) for the Tranh river hydropower plant No2 site, Quang Nam province, are presented. A regional earthquake catalog updated until 2014 and most-recent data on active faulting in the area with a radial extent of 100 km from the HPP site were used. Advanced techniques in ...
14 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 688 | Lượt tải: 0
High arsenic concentration in groundwater related to sedimentary facies in the Mekong River Delta, VietnamHigh content of As is usually found in 15- 70m wells around the Mekong and Bassac rivers located in the upper delta plain of the MRD. Some areas with a high density of 70- 80% tubewells have As levels of >500 µg/l located in Dong Thap and An Giang provinces. Most groundwater from 200 and 300 m in depth is safe. A combination of As concentra...
10 trang | Chia sẻ: honghp95 | Ngày: 30/11/2020 | Lượt xem: 734 | Lượt tải: 0
