KIẾN TẠO HIỆN ĐẠI VÀ CÁC TAI BIẾN ĐỊA CHẤT LIÊN QUAN Ở VÙNG BIỂN VIỆT NAM VÀ LÂN CẬN

SUMMARY Neotectonics and geological hazards in Vietnam Sea and surroundings This paper presents velocities of present-day tectonic movements in Vietnam and surroundings determined from GPS campaigns from 2007 to 2010. Absolute displacements and velocities of GPS stations in the IGS05 frame were determined. The result indicates that Lang station (LANG) moves eastward with slip rate of ~39mm/yr, southward with slip rate of ~11 mm/yr. The rate of Bach Long Vi (BLV1) is ~30mm/yr for the eastern component and ~11mm/yr for southern component. Song Tu Tay (STT1) moves eastwards with the rate of ~24mm/yr and southwards of 8mm/yr. Con Dao (CDA1) moves to the east with the rate of ~22mm/yr and to the south with the rate of ~6mm/yr. Dong Hoi (DOHO) move to the east with the rate of ~27mm/yr and to the south with the rate of ~8mm/yr. Hue (HUES) moves to the east with the rate of ~30 mm/yr and to the south with the rate of ~12mm/yr. HOCM move to the east with the rate of ~22mm/yr and to the south with the rate of ~10mm/yr. Calculate errors for both direction vary in 0.6 - 1mm/y. Based on seismic profiles, focal mechanisms and regional stress field, several fault segments in Pliocene - Quaternary sediments in East Vietnam Sea has been identified in Red River, Cuu Long and Nam Con Son basins with maximum of 15 km in length. Actual stress regimes in Vietnam and south Hainan basins being transitional demonstrate no source of large tsunami closing to Vietnam shelf. The subduction zone located at north Borneo is not active at present. Only Manila subduction zone is the source for large tsunami in East Vietnam Sea. Based on gravimetric field, topography, distribution of focal mechanisms in various depths and the rate of actual tectonic movement, 5 fault zones of the Manila subduction zone have been divided. The fault zones F3 and F4 can produce respectively maximum earthquake of 8.1 and 8.4. Modeling of displacement of fault zone F4 from the depth 15 to 20 km, 2m high of tsunami at Quang Ngai can be occurred. The depth of tsunami flood can be up to 4-5 m at some places in Quang Ngai and Da Nang

Nghiên cứu ảnh hưởng của các chất xúc tiến (M = Mn, Ce, Zr, và Cr) đối với hoạt tính xúc tác của vật liệu 15%Co/0,05m-SBA-15 trong phản ứng tổng hợp Fischer-Tropsch

This paper presents the effect of metal promoters (M = Ce, Cr, Mn  and Zr) on the catalytic performance of 15%Co/0.05M-SBA-15 catalysts for the Fischer- Tropsch synthesis. The results showed that the promoters were on SBA-15 influenced on the contribution of Co particles (shape, size, dispersion) on the walls of M-SBA-15 materials. These changes not only increased CO conversion but also significantly increased the liquid product C5+ selectivity. Catalysts were characterized by BET, XRD, TEM, UV-vis, H2-TPR, TPD-NH3, ICP. The catalytic performances of catalysts for Fischer-Tropsch synthesis were tested in a fixed bed reactor. The liquid product was analyzed by GC-MS to calculate hydrocarbon selectivity

Văn hoá tiền sử việt Nam

423 tr. : minh hoạ ; 21 cm

Văn hoá tiền sử việt Nam

423 tr. ; 21 cm

Văn hoá tiền sử việt Nam

423 tr. : minh hoạ ; 21 cm