Pyrolysis of transvaal kerogens I. Diagenesis of kerogen in a stromatolite near Zeerust,South Africa: One possible chemical evolution process     

Deborah S. Sklarew  Bartholomew Nagy 《Precambrian Research》1981,15(2):97-111

This study represents an attempt to understand some of the many post-lithification chemical processes which affect the evolution of kerogen. Kerogens separated from four carbonate stromatolites, collected over a horizontal distance of ～ 350 km from the Malmani Dolomite of the Olifants River Group in the Transvaal Supergroup, were characterized by combined vacuum pyrolysis—gas chromatography-mass spectrometry. The relative profiles of the gas chromatographic peak distributions and intensities (·finger print patterns’) of three of the kerogen pyrolyzates were closely similar. The Zeerust stromatolite kerogen yielded a different pattern, showing a greater abundance of higher molecular weight aliphatic and alkyl aromatic hydrocarbon moieties than the other three samples. Many of the stromatolites near the Zeerust area contain epigenetic fluorite introduced by aqueous solutions. Fluid inclusion homogenization analysis showed that the emplacement temperature of fluorite in the sample studied was 100–200°C. Fluoride ion initiated base catalyzed condensations may have been a feasible cause for the production of higher molecular weight aliphatic and (indirectly) some alkyl aromatic moieties in this stromatolite, as compared to those in the other three samples. Acid-catalyzed condensations may also achieve similar results in aqueous diagenetic environments.  相似文献   

Modelling of three-dimensional current systems associated with magnetospheric substorms     

Jerry L. Kisabeth  Gordon Rostoker 《Geophysical Journal International》1977,49(3):655-683

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Phytoplankton associations with the variable nepheloid layer on the Texas continental shelf     

Daniel Kamykowski  Jerry L. Bird 《Estuarine, Coastal and Shelf Science》1981,13(3):317-326

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DISCUSSION OF "Guest Editorial - A Closer Look at Deep Well Disposal of Wastes", by Raphael G. Kazmann, May-June 1981 issue, v. 19, no. 3, pp. 258–261     

Jerry Thornhill 《Ground water》1981,19(5):556-556

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Polarization of the broad Hα wing in symbiotic stars     

Jerry Jaiyul Yoo  Jih-Yong Bak  Hee-Won Lee 《Monthly notices of the Royal Astronomical Society》2002,336(2):467-476

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Seismic velocity structure of the ophiolite at Point Sal, southern California, determined from laboratory measurements     

Jerry Nichols  Nick Warren  Bruce P. Luyendyk  Paul Spudich 《Geophysical Journal International》1980,63(1):165-185

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Cognitive and Affective Predictors of Illinois Residents’ Perceived Risks from Gray Wolves     

Adam C. Landon  Maarten H. Jacobs  Craig A. Miller  Jerry J. Vaske  Brent D. Williams 《社会与自然资源》2020,33(5):574-593

Abstract

Increasing wolf populations are a concern for wildlife managers in the Midwestern U.S. Understanding the psychological mechanisms that contribute to public perceptions of risk will enable development of strategies that seek to mitigate these risks, and suggest where outreach efforts may facilitate acceptance of wolves. We examined the psychological factors that influence Illinois residents’ perceived risks from wolves. We hypothesized that individuals’ perceived risks from wolves were a function of their attitudes toward wolves, negative affect toward wolves, and basic beliefs about wildlife. Data were obtained from a survey of the Illinois public (n?=?784). Negative affect and attitudes toward wolves were direct predictors of perceived risks. Basic beliefs predicted attitudes and negative affect toward wolves. Negative affect predicted attitudes. Basic beliefs had direct and indirect effects on perceived risks.  相似文献   

Modeling core-scale permeability anisotropy in highly bioturbated “tight oil” reservoir rocks     

Nisael A. Solano  Mohammad Soroush  Chris R. Clarkson  Federico F. Krause  Jerry L. Jensen 《Computational Geosciences》2017,21(3):567-593

A high-resolution simulation model of a heterogeneous low-permeability rock sample is used to investigate the effects of physical and biogenic sedimentary structures on scaling and anisotropy of absolute permeability at the core scale. Several simulation sub-samples with random locations and volumes were also selected for evaluation of the effects of scale and lithological composition on the calculated permeability. Vertical and horizontal permeability values (from whole core simulation) are in good agreement with routine core analysis (RCA) measurements from offsetting cores. Despite relatively good reservoir quality associated with geobodies of biogenic and relic bedding structures, results from the full diameter core simulation demonstrate that their limited volumetric abundance and restricted connectivity prevent these features from controlling fluid flow in these rocks. In fact, permeability seems to be dominated by the tighter encasing matrix, which exhibits average permeability values very close to those reported from RCA. Geometric averaging offers a better representation for the upscaling of horizontal permeability datasets; whereas, both geometric and harmonic averaging work similarly well for the vertical measurements. The methodology used in this work is particularly applicable to the detailed characterization of reservoir rocks with a high degree of heterogeneity caused by biological reworking and diagenesis.  相似文献   

Wavefield analysis of crosswell seismic data     

Wasiu O. Raji  Youngxin Gao  Jerry M. Harris 《Arabian Journal of Geosciences》2017,10(9):217

Despite the numerous advantages of crosswell seismic data over surface seismic data, crosswell seismic geophysics is still underutilized and underdeveloped. The factors limiting the full utilization of crosswell data include the lack of standardized methods for processing and imaging the data. This is because crosswell data is not completely understood. To improve the understanding of crosswell data, we performed acoustic and elastic modeling of a west Texas carbonate oilfield data using finite difference methods and crosswell geometry. To account for the different wave modes in the field data, we decomposed the full data into its constituent wave modes. Results of the forward modeling show that elastic synthetic data is a better representation of crosswell field data than the popular acoustic synthetic data. Wavefield decomposition gave insight into the time-space kinematics behavior of the different wave modes that constitute the full data. Overall, the study improved our understanding of crosswell field data. The learning from this study has been utilized to perform data-driven reflection enhancement processing where the discerned characteristic of different seismic arrival is utilize to suppress unwanted and enhanced the desired wave modes. The processing reduced the complex data to only up-going P-P reflections that can be imaged to reveal the subtle geological structures of the oilfield.  相似文献   

Integrated Interpretation of Interwell Connectivity Using Injection and Production Fluctuations   总被引：1，自引：1，他引：0  

Ali A. Yousef  Jerry L. Jensen  Larry W. Lake 《Mathematical Geosciences》2009,41(1):81-102

A method to characterize reservoirs, based on matching temporal fluctuations in injection and production rates, has recently been developed. The method produces two coefficients for each injector–producer pair; one parameter, λ, quantifies the connectivity and the other, τ, quantifies the fluid storage in the vicinity of the pair. Previous analyses used λ and τ separately to infer the presence of transmissibility barriers and conduits in the reservoir, but several common conditions could not be easily distinguished. This paper describes how λ and τ can be jointly interpreted to enhance inference about preferential transmissibility trends and barriers. Two different combinations are useful: one is a plot of log (λ) versus log (τ) for a producer and nearby injectors, and the second is a Lorenz-style flow capacity (F) versus storativity (C) plot. These techniques were tested against the results of a numerical simulator and applied to data from the North Buck Draw field. Using the simulated data, we find that the F–C plots and the λ–τ plots are capable of identifying whether the connectivity of an injector–producer well pair is through fractures, a high-permeability layer, multiple-layers or through partially completed wells. Analysis of data from the North Buck Draw field shows a reasonable correspondence between τ and the tracer breakthrough times. Of two possible geological models for Buck Draw, the F–C and λ–τ plots support the model that has less connectivity in the field. The wells in fluvial deposits show better communication than those wells in more estuarine-dominated regions.  相似文献