The aim of this study was to measure polycyclic aromatic hydrocarbons (PAHs) in oysters (Crassostrea sp.) and gastropods (Cymatium sp.) collected from the Can Gio coastal wetland (CGCW), Vietnam. Samples were collected from 14 coastal sites, from both port and non-port sites, during a rainy season (September 2017) and a dry season (April 2018). PAH concentrations in oysters ranged from 3.26 to 64.45ngg–1 wet weight (WW), whereas in gastropods PAH concentrations ranged from 4.81 to 23.80ngg–1 WW. Naphthalene was the major component measured in oysters (0.71–46.74ngg–1 WW), whereas pyrene was the major congener measured in gastropods. Both species showed the same dominant accumulation pattern of two- to three-ring PAH compounds. A temporal and spatial distribution of PAHs in gastropods from the CGCW was also observed: higher PAH concentrations were more frequently observed in oysters and gastropods from port sites during the rainy season. The present study indicates that gastropods Cymatium sp. could be used as bioindicators in tropical coastal areas. Human health risk assessment conducted on the basis of the excess cancer risk suggests that there is no current risk to humans as a result of the consumption of oysters and gastropods.

The main purpose of the paper is to proposea lambda function and its apply to the concept of measurein comparing tuples of relations. Extend the generalizedpositive Boolean dependency to obtain a new type ofdependency called approximate generalized positive Booleandependency.The results can be applied in constructing more complicateddatabases, especially allowing extended search capabilitiesfor the real-world data.

Recent survey results indicate 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. From very early Miocene these basins have linked together and became 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 explorated adequately. The main risk is the drilling technology, the exploitation in the deep sea and high investment cost.

Commercial oil accumulation discovered in basement rocks of White Tiger oilfield opened a new exploration challenge for geologists and geophysics as well; simultaneously, it demonstrated the necessity to study this object more detail. A lot of results concerning research in basement rocks and mechanism of pore space formation were presented in several conferences or/and published in professional journals. Almost problems were clarified by researchers; however, for a comprehensive evaluation up to date the new data in which authors would like to focus on this paper, is determining the distribution of porosity in depth by logging data with supports of BASROC software version 3.0. When comparing the results of re-interpretation with additional new measurements with data summarizing 2006 show out that in basement rock the porosity decreases with depth; at zone V the porosity decreases to the value much lower than previous research results.

The paper presents the Kriging technique based on Matlab environment applied to interpolate the value of all points in the interpolation range from porosity values obtained from 13 wells of lower Miocene reservoir, ST Xam oil field. The MATLAB function meshgrids are used to create the interpolated cell (cell-Kriging) instead of point discrete interpolation. After selecting the Variogram model with nugget values and the correlation threshold (in scope), the next step is Kriging porosity values which regression permeability values. Finally, displays the values in the cells and interpolated coordinates X, Y, respectively. With input data the first mission is to analyze this set, select the necessary parameters and removal of useless data, and assess the scope of application of each type of data. Then combine the document with wellogging interpretation results to determine reservoirs and the layered in which filter out the corresponding data averaging and conducting. Based on the selected average value of the corresponding products in each well for each subclass, calculate the results of an empirical Variogram model as the basis for Kriging weighted matrix. The last work is to calculate error and evaluate the reliability of the Kriging results. The error of porosity model are minor and distributed apropriately with kriging range. However the results are numerous correlation. The permeability experiment results are collected just from 03 points, therefore the ultimate solution is recurred porosity from porosity Kriging results.