Fluid dynamics and fluid‐structural relationships in the Red Lake mine trend,Red Lake greenstone belt,Ontario, Canada

The Red Lake mine trend, a deformation zone in the Archean Red Lake greenstone belt that hosts the world‐class Campbell‐Red Lake gold deposit, is characterized by abundant foliation‐parallel iron‐carbonate ± quartz veins with banded colloform‐crustiform structures and cockade breccias overprinted by silicification and gold mineralization. There is an apparent incompatibility between the cavity‐fill structures of the veins and breccias (typically developed at shallow crustal depths) and the upper greenschist to lower amphibole facies metamorphic conditions recorded in the host rocks (indicating relatively deep environments). This, together with the development of veins along the foliation plane, represents an enigmatic problem that may be related to the interplay between fluid dynamics and stress field. We approach this problem through systematic study of fluid inclusion planes (FIPs) in the vein minerals, including the orientations of the FIPs and the pressure–temperature conditions inferred from fluid inclusion microthermometry. We find that fluid inclusions in the main stage vein minerals (pregold mineralization ankerite and quartz and syn‐ore quartz) are predominantly carbonic without a visible aqueous phase, whereas many inclusions in the postore stage contain an aqueous phase. Most FIPs are subvertical, and many are subparallel to the foliation. High fluid pressure coupled with the high wetting angles of the water‐poor, carbonic fluids may have been responsible for the abundance of brittle deformation features. The development of subvertical FIPs is interpreted to indicate episodic switching of the maximum principal compressive stress (σ₁) from subhorizontal (perpendicular to the foliation) to subvertical (parallel to the foliation) orientation. The subvertical σ₁ is favorable for the formation of foliation‐parallel veins, as fractures are preferentially opened along the foliation in such a stress regime, the origin of which may be linked to the fluid source.     

山东农业的可持续发展战略

山东是中国的农业大省,农业的发展对于全省经济的发展起着至关重要的作用。本文分析了山东农业经济的现状和当前存在的主要问题,从可持续发展的观点,提出了几点战略对策。     

Downward hydrocarbon migration predicted from numerical modeling of fluid overpressure in the Paleozoic Anticosti Basin,eastern Canada

The Anticosti Basin is a large Paleozoic basin in eastern Canada where potential source and reservoir rocks have been identified but no economic hydrocarbon reservoirs have been found. Potential source rocks of the Upper Ordovician Macasty Formation overlie carbonates of the Middle Ordovician Mingan Formation, which are underlain by dolostones of the Lower Ordovician Romaine Formation. These carbonates have been subjected to dissolution and dolomitization and are potential hydrocarbon reservoirs. Numerical simulations of fluid‐overpressure development related to sediment compaction and hydrocarbon generation were carried out to investigate whether hydrocarbons generated in the Macasty Formation could migrate downward into the underlying Mingan and Romaine formations. The modeling results indicate that, in the central part of the basin, maximum fluid overpressures developed above the Macasty Formation due to rapid sedimentation. This overpressured core dissipated gradually with time, but the overpressure pattern (i.e. maximum overpressure above source rock) was maintained during the generation of oil and gas. The downward impelling force associated with fluid‐overpressure gradients in the central part of the basin was stronger than the buoyancy force for oil, whereas the buoyancy force for gas and for oil generated in the later stage of the basin is stronger than the overpressure‐related force. Based on these results, it is proposed that oil generated from the Macasty Formation in the central part of the basin first moved downward into the Mingan and Romaine formations, and then migrated laterally up‐dip toward the basin margin, whereas gas throughout the basin and oil generated in the northern part of the basin generally moved upward. Consequently, gas reservoirs are predicted to occur in the upper part of the basin, whereas oil reservoirs are more likely to be found in the strata below the source rocks. Geofluids (2010) 10 , 334–350     

历史学的文学之翼:"现代叙史"

当代历史研究中,结构的、分析的、计量的史学大行其道,而叙述的历史学则遭到强烈排斥。这带来了两个严重后果:对科学的盲信和史学研究中人的缺乏。这些更进一步导致了当代史学远离大众,大众对历史学的兴趣急剧降低。“现代叙史”试图纠正这一弊病。它强调历史和文学的同质性,认为历史学应该大胆地借用现代文学手法,恢复历史学对人的关注和其叙事功能,重新赢得读者。     

建国初经济工作中的一项重大举措--陈云指导下的系列专业会议

建国初,陈云领导的中财委策划并指导召开了各项专业会议,这是新中国成立初期财政经济工作中的一件大事.各项专业会议研究了新中国经济工作的战略布局,确定了新中国经济恢复与发展的蓝图,并将<共同纲领>在财政经济工作方面规定的各项方针政策具体化.     

中国国民党“党国”体制述评

在西方政党政治潮流及苏俄体制的影响下,中国国民党总理孙中山形成了一套颇有特色的"党治"理念,为此后中国国民党执政体制奠定了理论基础.1926年,广州国民政府初步建立起中国历史上第一个"党国"体制.1927年4月,伴随着南京国民政府成立和全国统一,中国国民党继续实施其"党国"体制."党国"体制的核心在于,作为执政党的中国国民党,以党的意识形态作为治国的基本原则,以"党政双轨制"的权力管理体系作为自上而下的行政运作模式.这一独具特色的行政管理体制,既是西方政党政治理念特别是苏俄政党体制进入中国政坛的结果,也是传统中国政治文化与西方现代政党体制及理念相互作用的产物.由于理念与利益的分化,"党国"体制不仅形成了中国现代政治制度及其运作模式的重大变革,成为中国国民党统治体系内党、政、军利益纷争的根源,也由于党、政两条管理系统并存且关系滞碍而导致行政成本倍增,进而演变为中国国民党政治制度上的一大顽症.     

民国前期红十字会皖北救援活动管窥

民国前期,中国红十字会在救死扶伤的同时,不断拓宽人道主义服务领域。通过对这一时期中国红十字会皖北人道救助行动的考察,可以看出中国红十字会及其所属分会广泛参与兵灾、自然灾害及其他意外之灾的救助,减轻了民众疾苦,为保障民生,发挥了不能小视的作用。     

邓小平社会主义现代化建设思想的历史考察

“文化大革命”结束后,邓小平的全部理论活动和实践活动都是围绕社会主义现代化建设这个根本问题展开的。他从中国现代化模式的选择、现代化指导思想和理论基础的确立、现代化战略目标和步骤的规划,到现代化战略重点的设计方面,为中国社会的变迁提供了坚实的理论基础和实际可能性。     

第三代中央领导集体国际战略初探

冷战结束以后 ,面对西方国家的联合制裁和苏东剧变 ,第三代中央领导集体坚持独立自主的外交立场 ,采取灵活多样的外交手段 ,打破西方国家的联合制裁 ;冷静分析苏联解体后的国际局势 ,积极实施全方位外交战略方针 ,为社会主义现代化建设营造良好的外部环境 ;全面改善和调整大国关系 ,谋求面向 2 1世纪的新型伙伴关系的建立 ;面对经济全球化的趋势 ,实施积极主动参与和趋利避害相结合的国际战略方针 ,积极倡导和推动国际政治经济新秩序 ,将一个生机勃勃、在国际上有着举足轻重作用的社会主义中国带进了新世界的门槛