Continental Shelf Of Vietnam Research Articles

Sequence stratigraphy and evolution of the southern Central Vietnam Shelf during Late Pleistocene-Holocene

The central Vietnam continental shelf is located on the western margin of the East Vietnam Sea (South China Sea). This study provides new findings regarding the Late Pleistocene-Holocene evolution of the southern central Vietnam shelf off Binh Dinh province using high-resolution seismic profiles and sediment cores. The study found that the Late Pleistocene-Holocene sequence stratigraphic model of the study area can be divided into three systems tracts: the regressive systems tract (RST), the transgressive systems tract (TST), and the highstand systems tract (HST). The RST is the oldest and thickest of the three systems tracts and is characterized by forced regressive and lowstand deposits. These deposits likely formed between the Marine Isotope Stages (MIS) 5e highstand and the Last Glacial Maximum (LGM) termination. The RST is well-preserved at water depths deeper than 60 m and has a maximum thickness of about 40 m. The TST is the middle systems tract and was likely deposited during a postglacial transgressive period, from the LGM lowstand termination to around 8 cal ky BP. The TST is thickest in shallow water depths in the southern part of the study area and within incised-valley systems. The HST is the youngest of the three systems tracts and is dominated by thick mud clinoforms that prograde onto the shelf following mid-Holocene sea-level highstand until the present day. The HST was primarily deposited in shallow water depths of 0–50 m and decreases in thickness towards the outer shelf, ending at a water depth of around 80 m.The study also found that Late Pleistocene-Holocene relative sea-level change is the main factor controlling the overall stratigraphic organization of units on the study area. The presence of the beach-ridge structure at a water depth of approximately 140 m below the modern sea level in the southernmost part of the study area suggests that the region experienced a sea-level lowstand in the past. This lowstand was likely a result of subsidence due to a high sedimentation rate. This discovery is consistent with earlier studies conducted on the central Vietnam shelf. There are similarities in the deposition of Late Pleistocene-Holocene deposits between Binh Dinh and other shelves worldwide, indicating that there may be consistent controlling factors that govern the geological history of these regions. However, the thickness and distribution of deposits in the study area may be different due to local factors that interacted to shape the area differently than others.

Application of artificial neural network and seismic attributes to predict the distribution of Late Oligocene sandstones in the Cuu Long basin

Artificial neural network (ANN) has been widely applied in oil and gas exploration and production. This study presents the results of predicting the distribution of Late Oligocene sandstones in the Cuu Long basin based on the application of ANN and seismic attributes. These results have great significance, helping to orient the oil and gas prospection and exploration of the Cuu Long basin and other exploration objects on the continental shelf of Vietnam. The authors used unsupervised neural networks (UNN) and UNN methods constantly associated with the principal component analysis (PCA) to divide seismic facies. Seismic attributes such as Root mean square (RMS), Frequency, Envelope, Relative Acoustic Impedance (RAI), Phase, Sweetness, Amplitude, and t-Attenuation were analyzed and selected as input for the ANN training and testing process. These attributes can reflect changes in lithology, and sedimentary facies, from which will have a better view of the distribution of reservoirs in the study area. From 4 to 10 classes of seismic facies have been tested using each method to improve the results. Comparing the results of seismic facies classification by the UNN method and by UNN combined with PCA, it can be seen that the UNN combined with PCA will help reduce noise in seismic data better than UNN only. The research results have identified the distribution of Late Oligocene potential sandstones in the study area in the Cuu Long basin, which are mainly concentrated on the slopes of a large lake, with the direction of sediment transport from the West and Northwest.

Forecasting zonation of oil-gas prospects in the sedimentary basins of the Northeast Vietnam continental shelf based on gravity and borhole data

This study used the 2D and 3D normalized total gradient (NTG) method of gravity anomalies to detect the gravity anomalies caused by oil-gas reservoirs. The NTG of gravity anomalies can be associated with known oil-gas reservoirs, and most of them seem to be a good coincidence with the reservoirs. The closed minima of the NTG of gravity anomalies indicate the existence and locations of the density deficient anomalies closely related to the possible oil-gas reservoirs. The reliability of the NTG method depends mainly on the Fourier-developed coefficient N. Here, N is optimally selected by the borehole data. The 2D, 3D normalized total gradient method is applied in the sedimentary basins of the Northeast Vietnam continental shelf. Borehole data confirm the results of the method.

Research on evaluating, selecting and manufacturing the VPI SP chemical product for conducting field test to enhance oil recovery coefficient of oil fields in Cuu Long basin, offshore Vietnam

The Vietnam Petroleum Institute (VPI) is implementing a multi-task national level project entitled “Research, evaluate, select and develop a pilot programme for industrial application of solutions to improve oil recovery coefficient for clastic oil bearing reservoirs of oil fields in the Cuu Long basin, on the continental shelf of Vietnam”. Specifically, detailed evaluation studies have been carried out from geological characteristics, reservoir engineering, production to EOR mechanism to develop technical criteria for the process of manufacturing and evaluating the efficiency of the chemical system to optimise the laboratory scale, propose the production and injection scenarios to optimize the development plan as well as evaluate the efficiency of increasing oil recovery coefficient on the reservoir simulation model; conduct production at pilot scale and implement industrial application testing on the field scale for clastic oil bearing reservoir, Cuu Long basin.
 The article presents the results of research, evaluation, selection and successful manufacture of a VPI SP chemical system based on the combined mechanism of anionic - non-ionic surfactants and polymers to ensure satisfying the harsh technical requirements of oil fields in Vietnam such as resistance to high temperature, high pressure, high mineralisation, very low surface tension, optimal micro-emulsion, low adsorption onto reservoir rocks, reducing residual oil saturation in the reservoir. Results of the evaluation of increased efficiency of oil recovery on actual samples of Miocene reservoir showed an increase of over 21%. The VPI SP chemical system has been included in the plan of industrial-scale testing by Vietsovpetro in Bach Ho and other producing fields in the clastic sections of the Cuu Long basin.

Variation of sediment provenance at the 09 - 1 Block, Cuu Long Basin: their significance in assessing the Oligocene - Miocene reservoir quality

The Cuu Long Basin is one of the Tertiary sedimentary basins situated on the continental shelf of Vietnam, which demonstrates the high potential of oil and gas. Apart from fractured granite reservoirs, the Oligocene - Miocene sand bodies are thought to have significant potential for forming non - structural traps. The results of the study on the composition and physical properties of the sediments derived from wells "X" and "Y", block 09 - 1, Cuu Long Basin show that there is a clear difference between the Late Oligocene and Early Miocene sandstone in the well "X", namely the Miocene sandstone shows larger particle size, higher roundness and sortness (TB: 434.2; Ro: 0.69; So: 2.22) than those of the Late Oligocene sandstone (TB: 104.28; Ro: 0.64; So: 1.46). This difference is likely attributed to the fact that the Miocene sandstone was influenced by the marine environment, which intensified the roundness and sortness. Meanwhile, the well "Y" did not show much difference in the physical parameters of the sediments between the Late Oligocene and Early Miocene age ranges. However, the grain size was slightly increased and the roundness was less during the Early Miocene. It is possible that the “Y” well is located closer to the local source. The variation in the physical parameters of the sediments, proportion of sand grains and clay minerals shows that the quality of late Oligocene reservoir is better than that of Early Miocene reservoir, and the Late Oligocene reservoir quality in the "X" well is better than that in the borehole "Y".

Biostratigraphic and petrological characteristics of Cretaceous\u2013Paleogene sediments in the eastern Cuu Long delta

The basic structure of reservoir models is strongly affected by the stratigraphic interpretation and the properties of reservoir rock. The estimation of the volume of hydrocarbon accumulation will depend on the accuracy of predicting and distributing reservoir quality. Biostratigraphic and sedimentary petrologic results provide geological information to clarify the stratigraphy and properties of sedimentary rocks on the eastern margin of the Cuu Long delta plain trough. On the basis of stratigraphic correlation of the wells and studying the structures of the area, the deposition, thickness of sediments and the ability to correlate with prospect rocks on the southeastern Vietnam continental shelf were determined. The results have identified the basement rock of wells TC-1 and TC-2, which are Cretaceous metasandstones and were deposited in freshwater fluvial environments with high-energy conditions. The upper Paleogene sediments were overlaid directly on the Cretaceous basement rock in the TC-2 well but were completely absent in the TC-1 well. The lithologic composition is mainly feldspathic litharenite sandstone, which is formed in freshwater fluvial and freshwater lacustrine environments. This study provides new data on stratigraphic column of the eastern Cuu Long delta plain. The data show that the age of the sedimentary basement rock is Cretaceous which has not been determined in previous studies. The findings of this study can help for better understanding of the geological development history and the completely stratigraphic column of the Cuu Long delta to correlate with objects that are hydrocarbon accumulation in Cuu Long sedimentary basin in order to improve efficiency in petroleum exploration activities.

Combination of methodology on researching the petroleum formation process in Lower Miocene sediments, Cuu Long Basin

The process of formation and deposition of granular sedimentary formations containing oil and gas in sedimentary basins on the continental shelf of Vietnam is a key factor in the study to determine the distribution trend, characteristics and scale of the sedimentary formations in general and Miocene sediments in particular. Up to the present time, the majority of Vietnam's oil and gas exploitation basin are distributed on continental or coastal shelves, so the study of the origin and evolution of basins in general and components in particular (into reservoir system) still exists many gaps not only with geologists but also with petroleum research and exploration company on the continental shelf of Vietnam. The samples and data collected cover most of the onshore and offshore in Southeastern Vietnam, allowing the construction of the relationship boths the two areas that have traditionally been studied by the companys, with the lack of synchronous methods, closely links. The collection of research data, recently collected, created convenient conditions for linking and comparing the evolutionary history between the continental sediments and the continental shelf through the survey of collecting field samples and core samples at petroleum exploration drill wells come to clarify the origin, evolution, the trend of sedimentary materials transporting. The methodology conducted to research includes geotectonics, stratigraphic seismic analysis, borehole geophysical analysis, stress filed, core sample analysis, sedimentary lithological analysis, biostratigraphic analysis, analysis of U-Pb zircon isotope age and at last artificial intelligence. The study results can also be used to predict the presence and distribution of the Miocene sandstone petroleum formations in researching area.

ЭНЕРГЕТИЧЕСКОЕ СОТРУДНИЧЕСТВО НЕФТЕГАЗОВЫХ КОМПАНИЙ РФ И ВЬЕТНАМА. ПЕРСПЕКТИВЫ И ВЫЗОВЫ

The article shows the history of the energy cooperation develop- ment between oil and gas companies (OGC) of the Russian Federation (RF) and the Socialist Republic of Vietnam (SRV) on the continental shelf of Vietnam in the South China Sea. Despite the richest reserves of natural resources and, in particular, hydrocarbons in the territory of Vietnam, slightly less than half of the potential oil reserves and about a third of the potential natural gas reserves have been explored. The desire of the Vietnamese leadership to develop rela- tions in the oil and gas sector with foreign countries has led to the attraction of foreign oil and gas companies to the search, exploration and development of oil and gas fields on the shelf of the SRV in the South China Sea. Russian oil and gas companies are among the key partners in hydrocarbon production. The article shows the spheres of cooperation between Russian and Vietnamese oil and gas companies, its prospects and risks. The authors note that not only Russian oil and gas companies operate in Vietnam, but Vietnamese oil and gas companies have also gained access to Russian fields in the Russian Federation.

Characteristic foraminifera of the Pre-Cenozoic carbonate formations of Cat Ba island and northern Song Hong Basin, Vietnam

Pre-Cenozoic carbonate formations of the northern Vietnam continental shelf have recently become important petroleum exploration targets, owing to the discovery of hydrocarbon accumulations in the northern Song Hong Basin. However, there is limited stratigraphic information about the carbonate basement in the area; further, the stratigraphic relationship between carbonate formations exposed in adjacent areas, such as outcrops on Cat Ba Island and the subsurface Song Hong Basin, is unclear. This study revealed foraminiferal assemblages that can be used to determine the age of carbonate basement rocks based on samples from outcrops on Cat Ba Island and wells in the northern Song Hong Basin. Foraminifera were identified and divided into eight biozones and one assemblage that are indicative of different ages. Carbonate formations on Cat Ba Island originated from the Famennian to Moscovian, and those in the northern Song Hong Basin originated from the early Tournaisian to early Wuchiapingian. Carbonates in the basement section of well SH1 and the Cat Co, Hung Son, Hien Hao, and Gia Luan sections of Cat Ba Island, originated in the early-mid Tournaisian. In well SH2, basement carbonates are coeval with the upper part of the Gia Luan section, indicating that it originated in the late Serpukhovian to the late Moscovian. This age range is significantly different from the Late Devonian to Early Carboniferous age determined by previous studies. The youngest basement carbonates were identified in well SH3 (early Capitanian to early Wuchiapingian). As these carbonate formations are contemporaneous, they were governed by the same tectonic conditions and may exhibit similar geological characteristics. Therefore, reservoir rock models of the carbonate basement in northern Song Hong Basin could be used to clarify geological carbonate models for Cat Ba Island.

Quaternary benthic Foraminifera in the Tu Chinh - Vung May marine areas (continental shelf of Vietnam) and island, coral reef regions of the Truong Sa archipelago, Vietnam and their significance

The results of identifying and studying micropaleontological samples from the Quaternary sediments in the Tu Chinh - Vung May marine areas (1) and some coral reef islands of Truong Sa archipelago (2) have found more than 300 species of Benthic foraminifera, in which 291 species have been studied and described in detail, belonging to 112 genera, 43 families, 5 orders and 3 classes of the phylum Foraminifera. Among them, there are 19 new species, 3 new subspecies and 3 new genera. In the first region there are 195 species and the second one - 121 species (including 25 common species for both regions). They have important significations in the stratigraphic-biostratigraphic, ecological, paleogeographic studies, in sedimentary lithology... Regarding stratigraphy, the characteristic of Pleistocene is the first emergence of four genera: Baculogypsina, Cymbaloporetta, Parasorites, and Schlumbergerella; for Holocene - the appearance of the following genera: Ammomassilina, Baulogypsinoides, Cymbaloporella, Falsotextularia, Fijiella, Flintina, Gyroidina, Lugdunum, Neoconorbina, Planoperculina, Ptychomiliolata, Pseudoflintina, Pseudomassilina, Sahulia, Schlumbergerina, Septotextularia, Siphoniferoides, Tawitawia and Truongsaia. These fossils are the basis for dating sediment age, Quaternary stratigraphic division and correlation. In terms of paleoecology, benthic Foraminifera in the region (1) characterize the shallow offshore environment of the continental shelf, where there are the high and stable salinity, and the relatively strong environmental dynamics; in some places there are coral reef Foraminifera populations. In the region (2), they characterize the coral reef ecosystem of shallow and warm sea areas in the belt of tropical-subtropical climate of the Earth, where the salinity is high and stable, the transparency of water is high, and the environmental dynamics is relatively strong to strong... In addition, the paper also mentioned some other issues such as paleogeography (sea-level fluctuation), value of creating sediments of Foraminifera, environmental monitoring (for modern Foraminifera).

Investigation of long-term and short-term seismicity in Vietnam

In this paper, seismicity of the territory and continental shelf of Vietnam was investigated in depth using two earthquake catalogs representing long-term and short-term observation periods. The first catalog consists of 894 historical, field investigation and instrumental events covering a period of 880 years, from 1137 to 2017, and the second catalog consists of 587 events instrumentally recorded during 13 years, from 2005 to 2017. From these two catalogs, further subcatalogs were derived: The spatial analysis results show that the largest earthquakes with magnitude of 6.8 have occurred in the northwestern part of the country. Earthquakes with magnitudes exceeding 5.0 are distributed along known active faults systems, with high density in the territory of Northern Vietnam. Statistical methods were applied for declustering the 1a and 2a earthquake catalogs, and then the maximum likelihood method was used to estimate the a and b parameters of the Gutenberg–Richter law and the magnitude of completeness Mc for the territory of Vietnam and seismotectonic provinces. For the territory of Vietnam, the b-value determined for the long-term seismicity is around unit, while for the short-term seismicity, the b value reaches unit at the threshold Mc = 4.0. A time analysis method was carried out to investigate the distribution of waiting time of earthquakes in Vietnam, using Catalog 2b. Finally, a unified scaling law of earthquakes in Vietnam was established for both long-term and short-term seismicity cases, which links together the Gutenberg–Richter law, the Omori law of aftershocks, and the fractal dimensions of the faults.

Estimation of Curie point depths in the Southern Vietnam continental shelf using magnetic data

This study attempts to estimate the thermal structure in the Southern Vietnam continental shelf by calculating the Curie point depth isotherm using magnetic data. The Curie point depth values, from 49 overlapping blocks 128 × 128 km in size, have been estimated by the exponential approach. This approach is based on the analytical solution of the exponential equations obtained from transforming the magnetic anomaly data into the frequency domain. According to the obtained results, the range of Curie point depths is from 15.3 to 35.6 km. In the study area, the greatest Curie point depth is located in the South-Eastern part, and the smallest depth is located at North-Western part. The heat flows derived from the Curie point depths are also presented. The obtained results are at relatively high resolutions and in agreement with the published information available for the study area. The Curie point depths generally lie below the Moho surface in this region but lie above in some locations, notably the Cuu Long basin.

High Resolution Seismic for sequence stratigraphy interpretation of shallow sediments in the center Continental Shelf of Vietnam

Seismic stratigraphy analysis based on sequence stratigraphy has been developed strongly over the world. However, due to differences in development system of sedimentary basins, the analysis is different from place to place. In this paper, the authors will present seismic stratigraphy interpretation of sequence stratigraphy on shallow sediments of continental shelf of Vietnam, using HRS, determining the sedimentary system tracts and sequences in 4rd or 5th order, the relationship between sedimentary cycles, sea level change and tectonic movement, facial-paleogeographic characteristics and geological development history of Pliocene-Quaternary in the area. The interpreted seismic stratigraphic features assisted in defining the gross depositional environments, the relative sea level changes, shale/sand ratios, and locations of carbonate reefs and igneous rocks in the area

An improved space domain algorithm for determining the 3-D structure of the magnetic basement

The paper presents an improved algorithm based on Bhaskara Rao and Ramesh Babu’s algorithm to invert magnetic anomalies of three-dimensional basement structures. The magnetic basement is approximated by an ensemble of juxtaposed vertical prisms whose bottom surface coincides with Curie surface with the known depth. The computer program operating with the proposed algorithm is built in Matlab environment. Test applications show that the proposed method can perform computations with fast and stable convergence rate where the results also coincide well with the actual model structure. The effectiveness of the method is demonstrated by inverting magnetic anomalies of the southeast part of Vietnam continental shelf. The calculated magnetic basement relief of the study area provides useful additional information for studies in the aim of dealing with the geological structure of the area.References Beiki M., 2010. 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Application of power density spectrum of magnetic anomaly to estimate the structure of magnetic layer of the earth crust in the Bac Bo gulf. Journal of Marine Science and Technology, 14(4A), 137–148.Nguyen N.T., Bui V.N., Nguyen T.T.H., 2014b. Determining the depth to the magnetic basementand fault systems in Tu Chinh - Vung May area by magnetic data interpretation. Journal of Marine Science and Technology, 14(4A), 16–25.Nguyen T.T.H., Pham T.L., Do D.T., Le H.M., 2018. Improving algorithm of determining the coordinates of the vertices of the polygon to invert magnetic anomalies of two-dimensional basement structures in space domain, Journal of Marine Science and Technology (preparing to print).Parker R.L., 1973. The rapid calculation of potential anomalies, Geophys. J. Roy. Astron. Soc, 31, 447–455. Pilkington M., Gregotski M.E., Todoeschuck J.P., 1994. Using fractal crustal magnetization models in magnetic interpretation, Geophysical Prospecting, 42, 677–692.Pilkington M., 2006. 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The mechanism of formation, development and deformation of sedimentary basins in Viet Nam continental shelf

The sedimentary basins in area of Việt Nam continental shelf are located along the deep fault systems between the folded Indochinese block and Việt Băc-Hoa Nam platform and with the transitional zone. Is means that the zone attenuated continental crust. Due to that extruction of the Indochinese block toward the SoustEast which wrenched in right, in addition, due to the appearance of the thermal anomaly, producing the activity of Bien Dong seafloor spreading axis and drift of Australian–New Guinea plate toward Nord-East, induced some geodinamic factors to form many sedimentary basins in margins of Biển Dong Sea, such as: rift, pressure, extension, vertical slide cliff, horizontal displacement and wrench. These geodinamic factors created favourable conditions to form, develop and deform the sedimentary basins in Việt Nam continental shelf, followed the pull- apart type mechanism. But each sedimentary basin had its type of mechanism which depended on the concrete place of its basin from the Indochinese block and the thermal anomaly in Bien Dong Sea. Beside, itsformed condition for gas hydrate accumulations in some basins.

Determination of maximum tilt angle from analytic signal amplitude of magnetic data by the curvature-based method

Imaging buried geological boundaries is one of a major objective during the interpretation of magnetic field data in Geophysics. Therefore, edge detection and edge enhancement techniques assist a crucial role on this aim. Most of the existing edge detector methods require to obtain special points such as in general the maxima of the resulting image. One of the useful tools in estimating edges from magnetic data is the tilt angle of the analytical signal amplitude due to its value slightly dependence on the direction of magnetization. In this study, the maxima of the tilt angle of analytical signal amplitudes of the magnetic data was determined by a curvature-based method. The technique is based on fitting a quadratic surface over a 3×3 windows of the grid for locating any appropriate critical point that is near the centre of the window. The algorithm is built in Matlab environment. The feasibility of the algorithm is demonstrated in two cases of synthetic data as well as on real magnetic data from Tu Chinh-Vung May area. The source code is available from the authors on request.ReferencesAkpınar Z., Gürsoy H., Tatar O., Büyüksaraç A., Koçbulut F., Piper, JDA., 2016. Geophysical analysis of fault geometry and volcanic activity in the Erzincan Basin, Central Turkey, Complex evolution of a mature pull-apart basin. Journal of Asian Earth Sciences, 116, 97-114. Beiki M., 2010. Analytic signals of gravity gradient tensor and their application to estimate source location, Geophysics, 75(6), 159-174.Blakely R. J., and Simpson R.W., 1986. Approximating edges of source bodies from magnetic or gravity anomalies, Geophysics, 51, 1494-1498.Chen An-Guo, Zhou Tao-Fa, Liu Dong-Jia, Zhang Shu, 2017. Application of an enhanced theta-based filter for potential field edge detection: a case study of the LUZONG ORE DISTRICT, Chinese Journal of Geophysics, 60(2), 203-218.Cooper G.RJ., 2014. Reducing the dependence of the analytic signal amplitude of aeromagnetic data on the source vector direction, Geophysics, 79, 55-60.Cordell L., 1979. Gravimetric Expression of Graben Faulting in Santa Fe Country and theEspanola Basin, New Mexico. In Ingersoll, R.V., Ed., Guidebook to Santa Fe Country, New Mexico Geological Society, Socorro, 59-64.Cordell L and Grauch V.J.S., 1985. Mapping Basement Magnetization Zones from Aeromagnetic Data in the San Juan Basin, New Mexico, The Utility of Regional Gravity and Magnetic Anomaly Maps, Society of Exploration Geophysicists, Tulsa, 181-197.Hsu S.K., Coppense D., Shyu C.T., 1996. High- resolution detection of geologic boundaries from potential field anomalies: An enhanced analytic signal technique, Geophysics, 61, 1947-1957.Le D.C., Application of seismic exploration methods to identify geological structural characteristics supporting for hydrocarbon potential assessment in TuChinh - Vung May basin, Ph.D. Thesis, Hanoi University of Mining and Geology.Li X., 2006. Understanding 3D analytic signal amplitude: Geophysics, 71(2), 13-16.Miller H.G. and Singh V., 1994. Potential Field Tilt a New Concept for Location of Potential Field Sources, Journal of Applied Geophysics, 32, 213-217.Nabighian M.N., 1972. The analytic signal of two-dimensional magnetic bodies with polygonal cross-section: Its properties and use of automated anomaly interpretation, Geophysics, 37, 507-517.Nguyen N.T., Bui V.N., Nguyen T.T.H., 2014. Determining the depth to the magnetic basement and fault systems in Tu Chinh - Vung May area by magnetic data interpretation, Journal of Marine Science and Technology, 14(4a), 16-25.Nguyen X.H, San T.N, Bae W., Hoang M.C, 2014. Formation mechanism and petroleum system of tertiary sedimentary basins, offshore Vietnam, Energy Sources, Part A, 36, 1634-1649.Phillips J.D., Hansen R.O. and Blakely R.J., 2007. The use of curvature in potential-field interpretation, Exploration Geophysics, 38(2), 111-119.Rao D.B., and Babu N.R., 1991. A rapid method for three-dimensional modeling of magnetic anomalies, Geophysics, 56(11), 1729-1737.Roest W.R., Verhoef J., and Pilkington M., 1992. Magnetic interpretation using the 3-D analytic signal, Geophysics, 57, 116-125.Tran N., 2017. Sediment geology of Vietnam, VNU Press.Tran T.D., Tran N., Nguyen T.H., Dinh X.T., Pham B.N., Nguyen T.T., Tran T.T.T.N., Nguyen T.H.T., 2018. The Miocenedepositional geological evolution of Phu Khanh, Nam Con Son and Tu Chinh - Vung May basins in Vietnam continental shelf, VNU Journal of Science: Earth and Environmental Sciences, 34(1), 112-135.Vo T.S., Le H.M., Luu V.H., 2005. Three-dimensional analytic signal method and its application in interpretation of aeromagnetic anomaly maps in the Tuan Giao region, Proceedings of the 4th geophysical scientific and technical conference of Vietnam, Publisher of Science and Engineering 2005.Wijns C, Perez C and Kowalczyk P, 2005, Theta map: Edge detection in magnetic data, Geophysics, 70, 39-43.

Petrology, geochemistry, and Sr, Nd isotopes of mantle xenolith in Nghia Dan alkaline basalt (West Nghe An): implications for lithospheric mantle characteristics beneath the region

Petrology, geochemistry, and Sr, Nd isotopes of mantle xenolith in Nghia Dan alkaline basalt (West Nghe An): implications for lithospheric mantle characteristics beneath the region

Методика комплексного подхода к созданию оптимальной стратегии разработки на примере месторождения Белуга континентального шельфа Вьетнама

Методика комплексного подхода к созданию оптимальной стратегии разработки на примере месторождения Белуга континентального шельфа Вьетнама

Geochemistry of late miocene-pleistocene basalts in the Phu Quy island area (East Vietnam Sea): Implication for mantle source feature and melt generation

Geochemistry of late miocene-pleistocene basalts in the Phu Quy island area (East Vietnam Sea): Implication for mantle source feature and melt generation

The tectonic evolution and new exploration results onhydrocarbon potential, cased study in the NE-Eastern part, Cuu Long basin,Vietnam continental shelf

New exploration results proved the presence of Tertiary sedimentary basins with hydrocarbon potential in the boundaries of Vietnam continental shelf. These basins were perhaps formed in the Early Oligocene on the Mesozoic basement of continental crust and were filled with mainly deltaic clastic sediments. Since very early Miocene these basins have linked together and extended wider. Sediments of marine and prograding delta facies accumulated and widespreaded on the whole continental shelf. At the Middle Miocene to present-day the opening of the Bien Dong Sea (Vietnam East Sea), the regional tectonic subsidence and the eustatic fluctuation had created sedimentary formations of open and deep marine facies with turbidite shale, platform carbonate including reef build-up. Andesite and basalt extrusion occurred in form of dykes resulting from tectonic inversions in Late Oligocene, in the beginning of Middle Miocene, particularly in Late Miocene-Pliocene.
 These Tertiary sedimentary basins are expected to have hydrocarbon potential and need to be investigated and explored adequately. The main risk is the drilling technology, the exploitation in the deep sea and high investment cost.
 The recently exploration results in illustrated a better potential in Lower Oligocene reservoir in South East margin of Cuu Long basin and many new signs. These signs need to be highlight researched for predicting accumulation distribution in study area, in purpose of oil and gas exploration for next stages.