Accumulation, of hydrocarbons

For example, the many deepwater fields located in the Gulf of Mexico are of Tertiary age and are comprised of complex sand bodies which were deposited in a deepwater turbidite sequence. The BP Prudhoe Bay sandstone reservoir in Alaska is of Triassic/ Cretaceous age and was deposited by a large shallow water fluvial-alluvial fan delta system. The Saudi Arabian Ghawar limestone reservoir is of Jurassic age and was deposited in a warm, shallow marine sea. Although these reservoirs were deposited in very different depositional environments they all contain producible accumulations of hydrocarbons, though the fraction of recoverable oil varies. In fact, these three fields are some of the largest in the world, containing over 12 billion barrels of oil each ... 

A trap provides an impermeable barrier to the migration of hydrocarbons moving through a porous and permeable sedimentary bed. The trap allows the hydrocarbons to accumulate within the trap. The trap is a prerequisite for the formation of an accumulation of hydrocarbons and, therefore, for a reservoir [26]. 

The limitation of these instruments is that they only indicate overall corrosion rate. Their sensitivity is affected by deposition of corrosion products, mineral scales or accumulation of hydrocarbons. Corrosivity of a system can be measured only if the continuous component of the system is an electrolyte. 

A deep stratigraphic test is drilled to obtain information about a specific geological condition that might lead to the discovery of an accumulation of hydrocarbons. Such wells are customarily drilled without the intention of being completed for hydrocarbon production. This classification also includes tests identified as core tests and all types of expendable holes related to hydrocarbon exploration. 

The C02 can be stored in supercritical conditions, rising by buoyancy and can be physically held in a structural or stratigraphic trap, the same way as the natural accumulation of hydrocarbons occurs. The advantage of the capacity of containment system has been demonstrated by the retention of oil for millions of years. If the site is in production, it is used to increase the recovery of oil or gas (EOR recovery - enhanced oil, gas-enhanced recovery - EGR). These operations, EOR/EGR, provide an economic benefit that can offset the costs of the capture, transport and storage of C02. 

The explosive properties of liquid methane-oxygen mixtures were determined [8], Dining investigation of an explosion in a portable air liquefaction-separation plant, hydrocarbon oil was found in a silica filtration bed [9], The mechanism of slow heterogeneous accumulation of hydrocarbons dissolved in trace amounts in liquid oxygen on the liquid evaporator surfaces is discussed. It was concluded that months of continuous evaporation would be required to attain explosion-hazardous levels in real evaporators [10],... 

Accumulation of hydrocarbon vapors posing a potential fire or explosion hazard ... 

Schal, C., Gu, X., Burns, E. L. and Blomquist, G. J. (1994). Patterns of biosynthesis and accumulation of hydrocarbons and contact sex pheromone in the female German cockroach, Blattella germanica. Archives of Insect Biochemistry and Physiology 25 375-391. 

As part of the over-all topic of the role of inorganic ions in the formation of economic accumulations of hydrocarbons—i.e., oil-fields— the analogy with the formation of ore bodies stands out clearly. The closeness of the analogy is revealed in a number of instances where hydrocarbon accumulations actually accompany the formation of mineral deposits. Such occurrences are hydrothermal in character (117), and while the oil deposits are trivial in amount, the association is very real, being most commonly observed in the case of ore deposits involving lead, zinc, and uranium. 

Chiche et a/.[56] have studied the oligomerization of butene over a series of zeolite (HBeta and HZSM-5), amorphous silica alumina and mesoporous MTS-type aluminosilicates with different pores. The authors found that MTS catalyst converts selectively butenes into a mixture of branched dimers at 423 K and 1.5-2 MPa. Under the same reaction conditions, acid zeolites and amorphous silica alumina are practically inactive due to rapid deactivation caused by the accumulation of hydrocarbon residue on the catalyst surface blocking pores and active sites. The catalytic behaviour observed for the MTS catalyst was attributed to the low density of sites on their surface along with the absence of diffusional limitations due to an open porosity. This would result in a low concentration of reactive species on the surface with short residence times, and favour deprotonation and desorption of the octyl cations, thus preventing secondary reaction of the olefinic products. 

Accumulation of hydrocarbons along horizontal barrier rock - carrrier rock interface... 

The secondary hydrocarbon migration system influences both the distribution and the accumulation of hydrocarbons in a sedimentary basin (Table 6.1). Knowledge of the characteristics of a hydrocarbon migration pattern at a certain time during the basin s evolution, provides information on preferred paths of hydrocarbon migration and may indicate areas favourable or unfavourable for hydrocarbon accumulation during that time. In order to establish the amounts and nature of accumulated hydrocarbons and the exact location of the most favourable positions for hydrocarbon accumulation in a... 

The induction period was much shorter on SZ, possibly because accumulation of hydrocarbons species occurs to a lesser extent on its relatively low surface area. It is interesting to note that SZ catalysts show long induction periods for the isomerization of n-butane, a different reaction system (17). In that case, the induction periods appear because a bimolecular step is necessary for the reaction. Accordingly, the presence of induction periods and the accumulation of hydrocarbon molecules in the nitration reaction may suggest steps involving more than one aromatic ring. 

Underlying causes fog plus stable high, surface inversion, dispersal of primary pollutant emission Is prevented, accumulate of hydrocarbons sheltered basin, frequent stable highs, accumulation of secondary pollutants from photochemical oxidation... 

Accumulation of hydrocarbon species on the nickel surface which may slowly be converted into a polymer film (gum) blocking the surface. 

England, W. A. 1994. Secondary Migration and Accumulation of Hydrocarbons. In Magoon,... 

Unlike conventional oil and gas reservoirs, structure and stratigraphy often play a secondary role in the accumulation of hydrocarbons within a BCGS, primarily because of the dynamics associated with the abnormal pressure generation (Law 1984a,b, 1985, 1995 Masters 1979, 1984 Nuccio et al. 1992). BCGSs are often not in static capillary equilibrium which is usually manifested by capillary pressure transitions that are more a function of two-phase capillary seals than from structural closure (Iverson 1994 ... 

This element of the mass balance model refers to the efficiency with which the generated hydrocarbons migrate to and are trapped within the reservoir. Components of this element include the trapping mechanisms identified from the geological model as well as characterization of the reservoir seals. As discussed previously, structure often plays little or no role in the accumulation of hydrocarbons in a BCGS, so evaluation of the seals is especially critical to an accurate evaluation. Key components and data requirements include ... 

The Lower Series was deposited on a flooded erosion surface over a Paleozoic substrate, a marine surface on which were developed vast lagoons, volcanic flows, tidal flats and barriers. Truely marine conditions prevailed only over the northern part of the region. The sandstones of the Lower Series are not as uniformly continuous as those of the Tj and T. They are generally lenticular or sometimes form wedges interrupted by the volcanic rocks. A great potential for the accumulation of hydrocarbons in lithostratigraphic traps may develop under these conditions like in the sandstones in the upper part of the Lower Series in TKT-i, BKZ-i and BKZ-2. 

The nature of the lithostratigraphic traps varies with the level of the reservoirs located above the volcanic rocks (T-i and T-2) as well as below them (Lower Series). In the upper reservoirs (T-i and T-2) penetration of saline waters from the Saline Series (S1-S2-S3...) higher up has led to blockage of these sandstones which in petrophysical aspects are better sorted than those of the Lower Series. The same saline solutions almost completely destroyed the permeability of the sandstone T-2 which could have represented, among the Triassic reservoirs, a storage area of some importance for the accumulation of hydrocarbons. 

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