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Open access

M. Asad and H.U. Rahim

Abstract

The lower Indus basin is one of the prolific basins in Pakistan in which the C-interval of lower Goru formation act as a reservoir. With the help of petrophysical interpretation production zone is recognized and also porosity is calculated at the reservoir level. Through porosity we are able to calculate Ksat. A model based inversion of 2D seismic inversion was performed to ascertain three dimensional dispersion of acoustic impedance in the investigation zone and we have recognized new areas where porosity distribution is maximum and site which is suitable for new well. Porosity and Acoustic impedance are typically contrarily relative to each other. Presently porosity can be anticipated in seismic reservoir characterization by utilizing acoustic impedance from seismic inversion far from well position.

Open access

S. Abrakasa and H.O. Nwankwoala

Abstract

Some oil samples from various Nigerian oil fields were examined for the presence of Thermochemical Sulphate Reduction (TSR) derived organo sulphur compounds. Oil samples were diluted with DCM and injected into the GC–MS for full scan analysis. The GC–MS results show the presence 2–thiaadamantane, 1–methyl-2-thiaadamanatane and 5–methyl-2-thiaadamanatane, the compounds were identified by comparison of extracted spectras with literature. The presence of these compounds in oils has been accepted on a wider horizon as indicators of reservoir souring. The plot of 5–Methyl-2-thiaadamantane/Adamantane and Dibenzothiophene/Adamanatane showed a fair correlation, corroborating the presence of 5–Methyl-2-thiaadamantane and fairly high abundance of Dibenzothiophene, the plot of 2-thiaadamantane/Adamantane and 5–Methyl -2-Thiaadamantane/Adamantane corroborating the presence of 2-thiaadamantane and 5–Methyl -2-Thiaadamantane inferring that the presence of 2-thiaadamantane and 5–Methyl -2-Thiaadamantane indicate that reservoir souring is active.

Open access

Andre Prayogo, Sukir Maryanto and Ahmad Nadhir

Abstract

One of the areas that have geothermal potential in Indonesia is Tiris because there are found some manifestation in the form of hot springs. Several studies are needed to determine its geothermal potential before exploitation is carried out. Some previous studies have been carried out in the area, one of which uses Landsat 7 remote sensing data. There are other studies that state that knowledge of geology is needed to implement remote sensing in determining geothermal areas. This study uses 3-years data from Landsat 8 and geological information from the regional geological map of the study area. The result show changes in the value of Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) from year to year, where each year the NDVI value decrease which is interpreted as reduced vegetation in the study area. From the distribution of LST values in the study area, it was found that there were hot spots that had higher temperatures than the surrounding area. When geological information and LST distribution map overlaid with regional geological maps, it is known that the hot spots inside the research area are possible to be a geothermal reservoir.

Open access

M. O. Eyankware and C. Ogwah

Abstract

Groundwater samples were evaluated for irrigation purpose, within selected part of Oju area of Benue State, Nigeria. The study area lies within Asu River Group of the Lower Benue Trough, southern part of Nigeria. Physicochemical parameters were analyzed using APHA, 2012 method. Results from the study showed that pH falls within slightly basic to acidic, with Ec value ranging from 127 to 760 µS/cm, SSP ranges from 1.53 to 43.78, Sodium Percentage ranges from 1.55 to 77.8 %, Kelly Ratio ranges from 0.01 to 0.77, Magnesium Absorption Ratio ranges from 0.00 to 61.98 and total hardness Total Hardness ranges from 72.00 to 425.5 within the study area. The above listed parameters were below various permissible standard value for irrigation except for MAR at LBT/04, Na % at LBT/09, 13 and 14, SAR at 01 and 04 and TH at LBT/04 that were slightly above various permissible standard values. From Gibbs plot it was observed that rock dominance is the major factor that influences groundwater except for few sampling point were precipitation dominance was observed to have influence on groundwater within the study area.

Open access

Azatuhi Hovsepyan, Vahagn Muradyan, Garik Tepanosyan, Lilit Minasyan and Shushanik Asmaryan

Abstract

Lake Sevan being Armenia’s largest freshwater reservoir has a vital economic, recreational and cultural importance to both the catchment area and the nation as a whole. At present the Sevan which has seen the dramatic - some 20m drop - in water level entailing grave ecological consequences to the whole of its ecosystem, is at the stage of recovery. Hence, it is very important to study basic parameters describing the ecological status of the lake, and their annual and seasonal dynamics. The Sevan water surface temperature (WST) is a key parameter which influences all ecological processes that occur in the Lake. Declining lake level has brought to reduction of water volume and consequently to earlier warming of lake water in spring and its earlier cooling in the fall. Besides, more frequent becomes the complete surface freezing of Lake Sevan. Remotely sensed imagery makes it possible to get immediate information on a regular basis about WST across the entire surface of lakes. The purpose of this particular research was to study the space and time dynamics of Lake Sevan WST using Landsat 8 satellite imagery. The advantage of Landsat8 images is a regular frequency of capturing and availability of another thermal band that helps reduce the atmospheric refraction-induced errors/deviations. This research involved Landsat imagery for 2000-2018. The images underwent preprocessing steps (radiometric calibration, atmospheric correction, normalization etc) and then Lake Sevan WSTs and their monthly and annual changes over the mentioned periods were derived using both thermal bands (b10, b11). The research confirmed the fact, that Lake Sevan surface completely or partly freezing with periodicity of 2-3 years, whereas before the water drop the periodicity was 15-20 years. The study of spatial distribution of WST data derived from remote sensing shows that the temperature data corresponds to the overall general picture of temperature for Lake Sevan. This research has indicated that remotely sensed images and Landsat 8 imagery in particular allow derive both WST data on a regular basis and retrospective data (since 2013).

Open access

Arevik Minasyan

Abstract

Haematococcus pluvialis is a genus of green algae that keeps the high interest of the scientists for decades due to its capacity to synthesize astaxanthin. Among many others, astaxanthin is one of the most demanded natural anti-oxidant and the product of the future. It has the widest usage as source of nutrient rich food and health promoting compounds. Astaxanthin has got various applications in the nutraceuticals as immune system enhancer and anti-cancer agent, in the cosmetics as anti-aging component, as additive to food, as well as in the aquaculture industries. As a key requirement for the research in this field is to find out the better conditions and media to stimulate the H.pluvialis higher growth rate to reach in the field of microalgae economically sustainable cultivation and processing. The effect of WC versus BG-11 media to enhance growth rate of Haematococcus pluvialis has been examined. This study employed a parallel testing of stimulating effect of extra vitamins versus phosphorus. Combination of mentioned parameters with gentle shacking have been determined as multiple effectors that contribute to green algae cultures to grow to high density. Importantly, this study demonstrates that extra phosphorus contribute to growth rate of H.pluvilais positively, meanwhile addition of extra vitamins in combination with extra phosphorus impact both positively and negatively to promote cells division. Shacking influences the culture growth as either stimulator or repressor.

Open access

Georgiana Grigoraș and Bogdan Urițescu

Abstract

The aim of the study is to find the relationship between the land surface temperature and air temperature and to determine the hot spots in the urban area of Bucharest, the capital of Romania. The analysis was based on images from both moderate-resolution imaging spectroradiometer (MODIS), located on both Terra and Aqua platforms, as well as on data recorded by the four automatic weather stations existing in the endowment of The National Air Quality Monitoring Network, from the summer of 2017. Correlation coefficients between land surface temperature and air temperature were higher at night (0.8-0.87) and slightly lower during the day (0.71-0.77). After the validation of satellite data with in-situ temperature measurements, the hot spots in the metropolitan area of Bucharest were identified using Getis-Ord spatial statistics analysis. It has been achieved that the “very hot” areas are grouped in the center of the city and along the main traffic streets and dense residential areas. During the day the "very hot spots” represent 33.2% of the city's surface, and during the night 31.6%. The area where the mentioned spots persist, falls into the "very hot spot" category both day and night, it represents 27.1% of the city’s surface and it is mainly represented by the city center.

Open access

Areful Hoque

Abstract

Housing environment can influence our health in many ways. Health can be adversely affected by poor water quality, bad sanitation condition, nature of houses, housing using fuels and nature of works done by the dwellers for earning the bread. Bidi is also called poor man’s cigarette, made up of coarse uncured tobacco, tied with a string at one end. The bidi rolling is mainly a labor-intensive industry in India, coming under the category of un-organized sector, the lion share being women. The principle objective of this paper is to understand and analyze the quality of housing environment and status of health among the bidi workers. Malda district of West Bengal (India) has been selected as a study area, famous for mango cultivation and sericulture activities. The study is based on primary and secondary sources of data. Health is the most serious problems of workers in bidi industry. The working places of bidi industry are unhygienic, dingy and overcrowded, having little facilities of drinking water, even toilet facility and first aid. During the entire working time the bidi workers are exposed to tobacco fumes, thus these incidences create serious diseases (major and minor). The study also provoked that among the major diseases cough and cold diseases are mostly found (33.33 per cent) and Tuberculosis disease is at the lowest (9.00 per cent). The researchers suggested that there is an urgent need to issue the Health Card to the workers for treatment and curing of various diseases at government hospitals at subsidy rate.

Open access

Andreea-Mihaela Dunca

Abstract

Banat, a region situated in the western and south-western extremity of Romania, benefits from a defense network of meteorological stations in which a meteorological long-term monitoring activity of approximately 150 years is being carried out. Geographical position and diversity of physico-geographical conditions, under the influence of atmospheric circulation factors, determine both the major features of the climate in this region, as well as its local nuances. In order to analyze the spatial and temporal distribution of air temperature in Banat, we collected data strings and continuous meteorological observations from 14 weather stations in this area over a 35 years period (1979-2013). In Banat the air temperature regime presents a series of particularities and a patchy distribution as a result of the interaction of dynamic processes with the great diversity of these physicogeographical conditions. Analyzing the meteorological data strings one can observe that the air temperature varies in Banat, both spatially, from one meteorological station to another, and temporally from one year to another, from one semester to another, from one season to another but also from one month to the next due to the frequency and intensity of the advection of the different masses of air. The analysis of the air temperature and the thermal regime in Banat region confirms the moderate climate, with quite strong Oceanic influences from the western part of Europe and the weaker sub-Mediterranean influences, from the southwestern part of the continent. However, as a consequence of the global climate changes we are witnessing, at least in the last 50 years, there has also been a trend in Banat to increase the average annual temperature.