Sea surface shape derivation above the seismic streamer     

Robert Laws  Ed Kragh 《Geophysical Prospecting》2006,54(6):817-828

The rough sea surface causes perturbations in the seismic data that can be significant for time‐lapse studies. The perturbations arise because the reflection response of the non‐flat sea perturbs the seismic wavelet. In order to remove these perturbations from the received seismic data, special deconvolution methods can be used, but these methods require, as input, the time varying wave elevation above each hydrophone in the streamer. In addition, the vertical displacement of the streamer itself must also be known at the position of each hydrophone and at all times. This information is not available in conventional seismic acquisition. However, it can be obtained from the hydrophone measurements provided that the hydrophones are recorded individually (not grouped), that the recording bandwidth is extended down to 0.05 Hz and that data are recorded without gaps between the shot records. The sea surface elevation, and also the wave‐induced vertical displacement of the streamer, can be determined from the time‐varying pressure that the sea waves cause in the hydrophone measurements. When this was done experimentally, using a single sensor seismic streamer without a conventional low cut filter, the wave induced pressure variations were easily detected. The inversion of these experimental data gives results for the sea surface elevation that are consistent with the weather and sea state at the time of acquisition. A high tension approximation allows a simplified solution of the equations that does not demand a knowledge of the streamer tension. However, best results at the tail end of the streamer are obtained using the general equation.  相似文献   

Fatty acids in fossil fruits     

Michael Ed Hohn  W.G Meinschein 《Geochimica et cosmochimica acta》1977,41(2):189-193

Fatty acids extracted from six fruit of Nyssa fissilis from the Early Tertiary Brandon Lignite, Vermont, include mainly palmitic, palmitoleic, stearic, and oleic acids and a number of probable branched chain acids. Four unidentified ‘round fruit’ from the lignite contained the same acids in predominance. The two taxa were chemically indistinguishable because of wide intraspecific variation in percentage of each n-fatty acid present. ‘Fingerprint’ chromatograms of non-aromatic hydrocarbon extracts from two distinct taxa of fruit from an Eocene clay of Tennessee also showed no consistent interspecific differences. We conclude that degradation and removal of the seed food reserves and introduction of extraneous lipids limits the utility of fatty acids and hydrocarbons in chemosystematic study of fossil fruits at the species and genus levels.  相似文献   

Ecological regionalization in Canada and the United States     

Robert G. Bailey  Steven C. Zoltai  Ed B. Wiken 《Geoforum》1985,16(3):265-275

Present interest in environmental problems which are international, interstate or interprovincial in scope is drawing attention to the necessity for ecological regionalizations that will serve as a basis for intraregional transfer of experience. The major efforts at ecological regionalization by the national governmental agencies are described and compared. Although similar concepts have evolved in both countries, different systems of units have been developed for defining and mapping ecosystems at the regional scale. Before any regionalization is used it should be thoroughly tested, and modified if necessary.  相似文献   

储集层非均质性分析的计算机方法:以西弗吉尼亚州下密西西比系油田为例          下载免费PDF全文

迈克尔Ed.霍恩  罗纳德R.麦克道尔  戴维L.马特切恩 《沉积与特提斯地质》1995,(2):46-57

本文使用几种计算法和统计法研究美国西弗吉尼亚洲中部格兰尼克里克油田大Ｉｎｊｕｎ砂岩储集层的结构及其与采油量的关系。计算机程序根据已出版的资料编写，以适合（ｌ）计算渗透率对孔隙度的回归；（２）标绘三维孔隙度；（３）确定和标绘根据地球物理测井记录推断的相；（４）估算原始储量、累积产量和采油率。因为回归分析显示出测井记录和岩心孔隙度及岩心渗透率间微弱但重要的相关，所以，孔隙度可用干地层渗透率中以构成储集层的模式。也使用定量地层对比和多维定算法来估算在缺乏可用数据的情况下构造的影响。于井间使用克里格法内插绘制的剖面，突出了孔隙度较高的地带。使用地球物理测井资料和岩心描述，用聚类分析确定导电相。原始储量的估算结果与累计产量数据相结合，得出采油率的估算值。这些采油量变量图通常呈现在岩相图上观察到的相同的南北走向。  相似文献   

Major Brazilian gold deposits – 1982 to 1999     

Charles H. Thorman  Ed DeWitt  Marcos A. Maron  Eduardo A. Ladeira 《Mineralium Deposita》2001,36(3-4):218-227

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Monitoring Well Construction: The Differences     

Ed Hillman 《Ground Water Monitoring & Remediation》1990,10(4):78-78

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Book review     

W. E. Sharp  Michael Ed. Hohn  W. B. Hempkins 《Mathematical Geosciences》1988,20(1):63-68

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Zusammenhänge zwischen Brutwassertemperatur und Brutdauer,untersucht an Sandfelcheneiern aus dem Zürichsee     

Forstingenieur Ed. Ammann 《Aquatic Sciences - Research Across Boundaries》1949,11(1-2):263-276

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The legacy of Allan Hills 84001     

Derek Sears  Ed Scott  Paul Warren 《Meteoritics & planetary science》1998,33(4):545-546

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An experimental investigation of geochromatography during secondary migration of petroleum performed under subsurface conditions with a real rock     

Steve Larter  Berni Bowler  Ed Clarke  Colin Wilson  Brian Moffatt  Barry Bennett  Gareth Yardley  Dan Carruthers 《Geochemical transactions》2000,1(1):54-7

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