上扬子地区五峰组—龙马溪组黑色页岩高频层序划分

上扬子地区上奥陶统五峰组—下志留统龙马溪组是中国页岩气勘探开发最成功的层位。开展该套地层黑色页岩高频层序划分,有助于理解有机碳在页岩中的分布特征。以上扬子地区N211井的五峰组—龙马溪组黑色页岩为研究对象,分析了自然伽马（GR）与总有机碳含量（TOC）特征,基于旋回地层学理论划分了黑色页岩高频层序。结果表明：上扬子地区五峰组和龙马溪组下部黑色页岩GR值与TOC值整体上由五峰组底部到五峰组顶部的观音桥段逐渐变大,观音桥段出现极大值,再由观音桥段向龙马溪组逐渐变小。利用GR频谱分析及其滤波曲线,在五峰组和龙马溪组下部分别识别出约6个和7个长偏心率周期,据此,将五峰组和龙马溪组下部划分为12个完整的四级层序和1个不完整的四级层序。该研究可为黑色页岩高频层序划分提供典型案例,并为上扬子地区五峰组—龙马溪组页岩气甜点段预测提供参考,即：在五峰组—龙马溪组页岩高频层序结构中,层序边界附近的黑色页岩有机质富集程度相对较高。     

Exponential stability for formation control systems with generalized controllers: A unified approach

This paper discusses generalized controllers for distance-based rigid formation shape stabilization and aims to provide a unified approach for the convergence analysis. We consider two types of formation control systems according to different characterizations of target formations: minimally rigid target formation and non-minimally rigid target formation. For the former case, we firstly prove the local exponential stability for rigid formation systems when using a general form of shape controllers with certain properties. From this viewpoint, different formation controllers proposed in previous literature can be included in a unified framework. We then extend the result to the case that the target formation is non-minimally rigid, and show that exponential stability of the formation system is still guaranteed with generalized controllers.     

Domain Formations and Pattern Transitions via Instabilities in Soft Heterogeneous Materials

Experimental observations of domain formations and pattern transitions in soft particulate composites under large deformations are reported herein. The system of stiff inclusions periodically distributed in a soft elastomeric matrix experiences dramatic microstructure changes upon the development of elastic instabilities. In the experiments, the formation of microstructures with antisymmetric domains and their geometrically tailored evolution into a variety of patterns of cooperative particle rearrangements are observed. Through experimental and numerical analyses, it is shown that these patterns can be tailored by tuning the initial microstructural periodicity and concentration of the inclusions. Thus, these fully determined new patterns can be achieved by fine tuning of the initial microstructure.     

Study of the atypical formations in the corrosion bulks of an ancient bronze shield,by optical and electron microscopy

This article presents the atypical formations in the structure of the corrosion crust and in the partially mineralized metallic core, which resulted during the underground stay of a bronze shield, dated between the 1st century B.C. and the 1st century A.D. For our study, we choose a representative fragment from the rim of the shield, which was analyzed by optical microscopy and by electron microscopy coupled with energy‐dispersive X‐ray spectroscopy, to study its morphology, its composition, and the location of chemical compounds on the surface and inside the bulk formed during the underground stay, by processes of chemical and physical alteration, assisted by contamination with structural elements from the site. Those processes, by monolithization and mineralization formed a series of structures consisting of congruent elements and phases with a complex composition. Those formations, defined as surface effects generated by exogenous factors and endogenous factors inside the bulk, are frequently found in ancient bronze objects (such as the exterior flat mole formations and the Liesegang effect in the stratigraphic structure of the bulk). Some of those structures have atypical characteristics as regards their structure, composition, and formation mechanism, which may be used in archeometry. Moreover, that includes the object in the category of special cases, in terms of artifact evolution during underground stay and of the atypical formations resulted from the action of pedological and environmental factors. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.     

Methods of Minerals Modification by the Micro- and Nanoparticles of Gold and Platinum for the Evaluation of the Collectors Selectivity at the Flotation Processing of Noble Metals From the Fine Ingrained Ores

The paper explicates methods of the mineral surface coating by noble metals allowing to obtain samples with micro- and nanoparticles of Au and Pt, simulating natural objects. The purpose is to investigate the sorption and flotation properties of collectors. As a result we obtained the samples of pyrite, pyrrhotine, arsenopyrite, and quartz artificially enriched by micro-sized and nano-sized particles of noble metals. The coating of noble metals was carried out using the method of reducing adsorption from H₂[PtCl₆], H[AuCl₄], Na₂[PtCl₆], and Na[AuCl₄] solutions and the method of adsorption of nano-sized particles from Au and Pt sols. Depending on the conditions of the sulfides enrichment by noble metals and sizes of new formations of Au and Pt, we considered possible areas of application, methods of samples’ research, and reagents interaction with microparticles and nanoparticles of gold and platinum. A complex of research methods of reagents’ interaction with metals and flotation investigations of minerals and ores revealed the selective properties of new complexing collectors (perhydro-1,3,5-ditiazin-5-yl-methane (MTKH), sodium di(isobutyl)dithiophosphinate (DIF), 2-(ethylthio)ethylamine (ETEA)) due to their chemical interaction with gold and platinum.     

GWDC to Become Domestically First-class and Internationally Advanced General Contractor in Petroleum Engineering Technology Market

正Status Greatwall Drilling Company(GWDC),an integrated petroleum engineering services company,mainly focuses on drilling,geophysical prospecting,logging,cementing as well as the development of oil well construction including top driving,mud,and well completion.It provides general contracting services of well construction for oilfield development.What's more,GWDC devotes major efforts to reservoir geological study,workover and lateral drilling,acid fracturing treatment of formations,gas development,providing other rated technical services;It is dedicated to becoming the general contractor of petroleum engineering technologies in the world.     

云阳—涪陵地区长兴组—飞仙关组沉积相研究

运用层序地层学的理论和方法,将云阳—涪陵地区长兴组—飞仙关组划分为4个三级层序,包括8个体系域,进一步建立相关层序地层格架。通过对层序地层格架内沉积相展布的研究,发现该地区长兴组—飞仙关组发育台缘礁滩和潮坪及台内礁滩有利储集相带,并受开江—梁平海槽的控制,沿海槽两侧呈条带状分布。此外,还受气候背景和台缘类型、台地部位及其类型以及海底高地貌的控制。在有利储集相带分布预测成果的基础上,结合多种地质信息进行综合分析,将研究区划分为5类有利勘探区带,即台缘礁区、台缘滩区、台缘潮坪区、台内礁区及台内滩区,其中台缘礁滩及潮坪区是最为有利的勘探区带和当前勘探的重点;台内礁滩区是台缘礁滩区的补充,可望取得突破。     

特低渗透油田注水地层结垢矿物特征及其影响

通过注入水和地层水的配伍实验、检查井岩心矿物鉴定、孔隙度与渗透率恢复实验,研究了安塞特低渗透油田注水地层结垢对地层孔隙度和渗透率的影响.结果表明,注入水为Na2SO4型,地层水为CaCl2型且含Ba2+,由于注入水和地层水不配伍.储层长期注水后形成了较为丰富的结垢矿物即方解石、重晶石.结垢矿物的生成量与孔隙度、渗透率的下降幅度具有很好的相关性.注水开发20年后,孔隙度平均下降幅度为15%.渗透率平均下降幅度为31.73%.就储层伤害而言,碳酸钙垢大于硫酸钡垢.     

随钻声波测井响应数值模拟分析

随着随钻声波测井技术的蓬勃发展,该技术已成功应用于地层纵波速度测量,但对地层横波速度测量,尤其是慢速地层横波速度测量则仍存在困难。应用圆柱坐标系下三维时域有限差分方法数值模拟了随钻多极子声波测井响应,通过计算所得模式波频散曲线以及随钻测井响应,对随钻测井环境下井孔内多极声场传播的特点和规律进行了详细分析。结果表明,在快速地层中,随钻偶极子声波测井响应主要由速度略低于地层横波速度的模式波和速度低于流体声速的模式波构成,而随钻四极子声波测井响应曲线主要由速度接近于地层横波速度的模式波和声速接近于流体声速的模式波构成;对慢速地层情况,随钻偶极子声波测井响应主要由钻铤弯曲模式波和地层弯曲波构成,随钻四极子声波测井响应则主要由地层四极子波构成;由于钻铤模式波对地层横波测量具有强烈干扰,并且地层弯曲波速度与地层横波速度有较大差别,因此随钻偶极子声波测井仪器在慢速地层中直接测量横波速度是不合适的;而地层四极子波在低频下不存在钻铤模式波或可以降低钻铤模式波对测量结果的干扰,且在低频时以地层横波速度传播,因此随钻四极子声波技术适合用于测量慢速地层横波速度。该结论为充分利用随钻声波测井信息和设计随钻声波测井仪器提供了理论依据。