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711.
Benyamin Khadem Mohammad Reza Saberi Mohammad Eslahati Bita Arbab 《Geophysical Prospecting》2020,68(5):1613-1632
Rock typing and flow unit detection are more challenging in clastic reservoirs with a uniform pore system. An integrated workflow based on well logs, inverted seismic data and rock physics models is proposed and developed to address such challenges. The proposed workflow supplies a plausible reservoir model for further investigation and adds extra information. Then, this workflow has been implemented in order to define different rock types and flow units in an oilfield in the Persian Gulf, where some of these difficulties have been observed. Here, rock physics models have the leading role in our proposed workflow by providing a diagnostic framework in which we successfully differentiate three rock types with variant characteristics on the given wells. Furthermore, permeability and porosity are calculated using the available rock physics models to define several flow units. Then, we extend our investigation to the entire reservoir by means of simultaneous inversion and rock physics models. The outcomes of the study suggest that in sediments with homogeneous pore size distribution, other reservoir properties such as shale content and cementation (which have distinct effects on the elastic domain) can be used to identify rock types and flow units. These reservoir properties have more physical insights for modelling purposes and can be distinguished on seismic cube using proper rock physics models. The results illustrate that the studied reservoir mainly consists of rock type B, which is unconsolidated sands and has the characteristics of a reservoir for subsequent fluid flow unit analysis. In this regard, rock type B has been divided into six fluid units in which the first detected flow unit is considered as the cleanest unit and has the highest reservoir process speed about 4800 to 5000 mD. Here, reservoir quality decreases from flow unit 1 to flow unit 6. 相似文献
712.
713.
A novel, cost-effective, and simple electrocatalyst based on a Pt-modified glassy carbon electrode(GCE), using cetyltrimethylammonium bromide(CTAB) as a cationic surfactant, is reported. Amphiphilic CTAB molecules were adsorbed on GCE by immersion in a CTAB solution. The positively charged hydrophilic layer, which consisted of small aggregates of average size less than 100 nm,was used for accumulation and complexation of [PtCl2. anions by immersing the electrode in Ksolution. The modified electrode was characterized using scanning electron microscopy,energy-dispersive X-ray spectroscopy, impedance spectroscopy, and electrochemical methods. The electrocatalytic activity of the Pt particles in the hydrogen evolution reaction(HER) was investigated.The results show that the CTAB surfactant enhances the electrocatalytic activity of the Pt particles in the HER in acidic solution. 相似文献
714.
This paper reviews the development of ship anti-roll tanks from the 1880s to the present day including their modelling and control strategies. Mention is also made of other ship roll stabilization systems and the application of the technology to stabilization of other structures. The potential for the use of roll stabilization tanks on modern, high speed multi-hull craft which also have a low speed operational requirement is also discussed. 相似文献
715.
Online GPS processing services: an initial study 总被引:1,自引:2,他引:1
There are a number of online Global Positioning System (GPS) processing services that provide GPS processing results to the
user free of charge and with unlimited access. These services provide solutions for a user-submitted Receiver Independent
Exchange Format (RINEX) file based on differential methods using reference stations or precise point positioning using precise
GPS orbit and clock data. Different data sets varying in time and location were submitted to the online services and their
results compared. Although the quality of results depends on many factors, in most cases the users can expect reliable online
processing results for a 10-h data set made by a geodetic dual frequency receiver anywhere in the world. 相似文献
716.
Watershed modeling of rainfall excess transformation into runoff 总被引:2,自引:0,他引:2
Mohammad Reza Najafi 《Journal of Hydrology》2003,270(3-4):273-281
In this paper an attempt is made to present a distributed physiographic conceptual model that uses the principles of flow continuity and momentum. For this purpose, the watershed under study is divided into subwatersheds keeping in view the drainage patterns and characteristics. Then the main tributaries are identified and their drainage areas are delineated to form tributary subwatersheds. The main channel subwatersheds have taken care of the remaining area in the vicinity of the main channel. The kinematic wave theory is applied for the overland runoff computations from these subwatersheds. Further, the overland flows are superimposed onto the main channel. The dynamic wave theory is used to route the flows through the main channel to compute the watershed responses at the outlet. The proposed model is tested onto a natural watershed. The computations were performed for few storm events. Comparison of the significant parameters of the computed and the observed hydrographs shows that the maximum relative error in prediction is 5.8%. Thus, the results are satisfactory. Better results can be obtained when measured rainfall-excess data are available or a more realistic loss index is adopted for rainfall-excess separation. 相似文献
717.
Reza Sheikholeslami Hervé Bellon Hachem Emami Mossaı̈eb Sabzehei Alain Piqué 《Comptes Rendus Geoscience》2003,335(13):981-991
The metamorphic rocks of the Neyriz area (Sanandaj–Sirjan zone) represent a Palaeozoic sequence, the upper part of which being palaeontologically dated from the Carboniferous and the Permian. Field structural analysis of the whole sequence, detailed in laboratory by microstructural one and 40K–40Ar dating carried on separated minerals, lead to establish that the whole sequence, from gneisses to Permian rocks, has suffered a unique synmetamorphic deformation, of variable intensity, marked by a foliation. Isotopic ages measured on extracted amphiboles and micas, clustered in four groups between 300 and 60 Ma, show the successive stages of their slow exhumation, which ended by the end of the Cretaceous. To cite this article: R. Sheikholeslami et al., C. R. Geoscience 335 (2003). 相似文献
718.
Mohammad Reza Hosseinnejad 《中国地质大学学报(英文版)》1998,9(2):2
INTRODUCTIONAhydrocarbonanomalyisgeneralydefinedasthechangeinvalueofoneormorehydrocarbonsinthefieldcomparedtobackgroundlevelo... 相似文献
719.
Mohammad Ebrahimi 《中国地质大学学报(英文版)》1998,9(1):2
INTRODUCTIONThestudiedareaislocatedinthenorthofGolpayegan,Iran,boundedbylatitudes33.31°Nand33.37°Nandlongi-tudes50.11°Eand50.... 相似文献
720.
A late Pleistocene long pollen record from Lake Urmia, NW Iran 总被引:4,自引:0,他引:4
Morteza Djamali Jacques-Louis de Beaulieu Madjid Shah-hosseini Valrie Andrieu-Ponel Philippe Ponel Abdolhossein Amini Hossein Akhani Suzanne A.G. Leroy Lora Stevens Hamid Lahijani Simon Brewer 《Quaternary Research》2008,69(3):413-420
A palynological study based on two 100-m long cores from Lake Urmia in northwestern Iran provides a vegetation record spanning 200 ka, the longest pollen record for the continental interior of the Near East. During both penultimate and last glaciations, a steppe of Artemisia and Poaceae dominated the upland vegetation with a high proportion of Chenopodiaceae in both upland and lowland saline ecosystems. While Juniperus and deciduous Quercus trees were extremely rare and restricted to some refugia, Hippophaë rhamnoides constituted an important phanerophyte, particularly during the late last glacial period. A pronounced expansion in Ephedra shrub-steppe occurred at the end of the penultimate late-glacial period but was followed by extreme aridity that favoured an Artemisia steppe. Very high lake levels, registered by both pollen and sedimentary markers, occurred during the middle of the last glaciation and late part of the penultimate glaciation. The late-glacial to early Holocene transition is represented by a succession of Hippophaë, Ephedra, Betula, Pistacia and finally Juniperus and Quercus. The last interglacial period (Eemian), slightly warmer and moister than the Holocene, was followed by two interstadial phases similar in pattern to those recorded in the marine isotope record and southern European pollen sequences. 相似文献