强制性海退沉积物与油气分布

强制性海退形成于相对海平面下降期间,对应于早期低位体系域的快速下降和缓慢下降以及晚期高位体系域的缓慢下降,引起沉积环境向海方向的迁移;当沉积物供应充足时,在斜坡边缘地区可以发育典型的进积斜坡沉积,表现在地震剖面中常为前积斜交反射结构。随滨岸线向海退却,在近岸一侧或浅海环境通常缺失低位体系域或陆架边缘体系域,强制性海退形成的砂体沉积往往离岸较远;缓慢下降期的晚期高位体系域也是强制海退的产物。强制性海退可以形成准层序边界和层序边界相一致的特殊现象,层序边界可以构成准层序边界的底界、顶界。     

明朝南京城市建设思想浅析

明朝南京城市建设独具特色,其不规则的平面形式、＂四重城＂的结构等都迥异于在此之前的都城形式,这样的形式反映出当时的建城思想,包括我国古代传统的两大建都思想、南京城市功能的演变以及传统文化的影响等方面。     

郯庐断裂带张八岭隆起北段晚中生代岩体的成因

郯庐断裂带张八岭隆起北段分布着一些晚中生代岩体,其侵位时间在120~128 Ma之间,稍晚于同期华北克拉通内江苏徐州和安徽宿州地区(简称徐宿地区)。文章通过对上述两地区的地球化学特征的对比研究,认为张八岭隆起北段岩体的岩浆来源可能是壳-幔岩浆混合形成的,并可能经历了一定的岩浆分异作用;而徐宿地区岩浆可能与深部地壳物质的部分熔融有关。上述结果表明,张八岭隆起北段岩浆来源深度较华北克拉通内部徐宿地区深,断裂带内具有较强的伸展活动及岩石圈减薄程度。分析认为,断裂带的存在和活动在岩石圈减薄过程中具有诱发和促进作用。     

论大连营城子汉墓壁画与“羽化升仙”思想观念的传播

营城子汉代墓内壁画的升天图生动反映了汉代“羽化升仙”的思想,具有鲜明的时代特征。对该墓出现的历史地理背景、壁画反映的思想观念及其影响略加探析,认为汉代中原的先进文化已经扩及大连地区。营城子汉墓考古成果证明,大连地区的汉墓群与中原地区密不可分,有着丰富的文化底蕴。     

满蒙贵族联盟的形成与演变

清代前期,满洲皇帝对蒙古的基本政策是,与蒙古贵族广泛建立联盟,使之成为其政权的可靠支柱。同时采取有力的措施,限制其势力扩大而便于控制。结果,不仅消除了蒙古势力对清王朝的威胁,而且使其成为维护国家统一与边疆稳定的钢铁屏障。在前人研究的基础上,探讨了满蒙贵族联盟的形成、发展及联盟内部控制权等问题,并肯定了这一联盟对清代国家统一与民族和谐所起的作用。     

Structural deformation and fault activity of the Tan-Lu Fault zone in the Bohai Sea since the late Pleistocene

The Tan-Lu Fault zone (TLFZ) is a significant fractural zone in eastern China and also a seismicity belt in North China. Based on total 4000-km-long shallow penetrated single seismic data with high-resolution, structural deformation and fault activity of the TLFZ in the Bohai Sea since the late Pleistocene are discussed in detail. The results show that the TLFZ with a discontinuous distribution and a general NNE-trending consists of 14 active subfaults with an NNE or NE strike in the Bohai Sea. Seismic data reveal that de-formation zones along the subfaults in the central Bohai Sea and the Laizhou Bay are wider and more complex than those in the Liaodong Gulf. Related folds and lots of secondary normal faults which are characterized by nearly vertical fault planes and a same or reverse dip construct the fractural zone in the Laizhou Bay and the central Bohai Sea. Usually, micro symmetrical grabens develop on the top of anticlines. In the Liaodong Gulf, subfault fractural zones usually consist of secondary normal faults with the same inclination or opposite inclination. Ages of seismic sequences and cutting relation between subfaults and seismic sequences suggest that the latest faulting age of the TLFZ is the end of the late Pleistocene in the Liaodong Gulf and the early Holocene in the Laizhou Bay and the central Bohai Sea. There is a good match between distribution of earthquakes and that of the subfaults in the Laizhou Bay and the central Bohai. Statistical result shows that total vertical offset of the TLFZ since the late Pleistocene ranges from 6 to 11 m. On the basis of offsets of the subfaults, the vertical slip rate is calculated and results show that average vertical slip rates in the central Bohai Sea are larger than those in the Liaodong Gulf and the Laizhou Bay. Slip rates more than 0.06 mm/a during 23–10 ka B.P. and 85–65 ka B.P. are larger than those in other stages. The TLFZ was mainly dominated by tensional normal component since the late Pleistocene. Synthesizing shallow deformation, activity and distribution of earthquakes, the TLFZ in the Bohai Sea can be divided into three segments: the Laizhou-Bay segment, the Bozhong segment, and the Liaodong-Gulf segment.     

Palaeoclimatic evolution recorded by multidicipline in sediments in gahai lake, qaidam basin since late last deglacial

Based on the analyses of Loss-on-Ignition (LOI), carbonate content and sediment characteristics, this paper reconstructs the climatic and environmental evolution of the Gahai Lake area since the late Last Deglacial Period.The results cover the late Last Deglacial Period and the Holocene.The climate was very unstable and rather arid during the late Last Deglacial Period.The Holocene can be divided into three pe-riods:the early Holocene (11360-8240 cal aB.P.), which was dry but unstable and featured rising tem-peratttres, the mid-Holocene (8240-3200 cal aB.P.), which was warm and wet and the late Holocene (since 3200 cal aBP), which was cold and dry.Results also show a warm-wet event around 1500 cal aB.P.     

启蒙与救亡：清末音乐教育的两大功能

清末音乐教育具有启蒙与救亡两大功能。清末音乐教育的启蒙功能主要体现在以音乐为载体的精神教育、以音乐塑造新的国民性、音乐教育的美育功能三个方面。清末音乐教育的救亡功能主要体现在教育救国与音乐救国,军队乐歌的激励斗志和保家卫国,以及音乐团体的鼓舞国民和挽救国家的功能三个方面。     

清初三角学研究中的学术精神

清初中算家秉持正确的标准评判中西算法之优劣,悉心洞察前人成果之利弊,从而在三角学研究上取得丰富的成果,弥补、纠正了传入三角学知识的种种疏漏和讹误,促使三角学发展成为一门独立完善的数学分支,有力驳斥了当时拘守成法、空论疏学等不正学风。他们的科学研究工作彰显出"求是"、"求真"、"甘为津梁"、"嘉惠后学"的学术精神,对清初科学发展产生重大影响,犹可借鉴。     

甘肃北山桥湾北花岗岩体的年代学、地球化学及其地质意义

为加深对北山晚古生代构造演化的认识, 选取位于甘肃北山南带、敦煌地块北缘的桥湾北花岗岩体进行年代学、地球化学研究。桥湾北角闪石花岗岩体锆石LA-ICP MS年龄为303.7±2.4 Ma, ε_Hf(t)为-1.2~5.8, ε_Nd(t)相对较高(-0.40~-0.06), (⁸⁷Sr/⁸⁶Sr)_i =(0.704524~0.705062)。 桥湾北花岗岩体K₂O含量为4.09%~5.58%, 属高钾钙碱性岩石, A/CNK值在0.92~1.04之间, 为I型花岗岩; 微量元素较富集LILE, 相对亏损HFSE, 有明显的Nb, Ta负异常。岩体具相对富集的微弱分馏的轻稀土元素, 重稀土元素分馏不明显, 基本没有Eu异常。由Hf, Nd同位素及地球化学特征判断, 桥湾北花岗岩体为壳幔混合成因, 其形式可以是底侵的幔源岩浆再分异, 上升过程中遭受地壳物质混染。根据区域构造背景及岩石学、地球化学特征, 可以认为桥湾北岩体是北山南带后碰撞过程岩浆活动的产物, 反映出在晚石炭世北山地区的碰撞拼贴已经完成。