陇县地区新街片麻岩套锆石年龄及其地质意义

目的寻找秦-祁结合部位早古生代岛弧型岩浆活动的证据,为秦岭和祁连造山带的对比研究提供依据。方法依据岩石主、微量地球化学特征判别新街片麻岩套的构造属性,并通过LA-ICP-MS对其中的锆石进行U-Pb测年。结果新街片麻岩套富集大离子亲石元素（LILE）和轻稀土元素（LREE）,亏损高场强元素（HSFE）和重稀土元素（HREE）,指示其形成与俯冲作用有关,在构造判别图解中落入岛弧火山岩范围;U-Pb锆石测年结果显示,花岗质片麻岩的形成年龄为447.7±5.4Ma。结论该年龄与北秦岭和北祁连造山带内部的岛弧火山岩活动的时限一致。     

清水江文书天柱卷史料价值续探——贵州辛亥革命后文书中的宣统纪年

清水江文书是贵州东南部与周边地区社会生活、历史面貌的原始契约档案,其中立契时间中就包含着丰富的历史年代信息。贵州经过辛亥革命后,虽然鼎革改元,有了新的纪年方式,但是由于地处偏远或者乡间习惯的原因,“宣统”纪年仍在此间延续。文书中保留的这些纪年方式,也可以和其它历史资料印证,展现了复杂的历史面貌,具有重要的史料价值。     

试论月龄历谱的数理结构及编排规则

运用数理统计方法,借鉴天文历算及历谱编排的有关知识,试图提供一种被称为月龄历谱的数理结构模型（数表）,以作为对具有某些月龄特征的词语的研究工具。其用途：（1）由这些月龄词语的干支差直接得出它们可能的年代间隔;（2）可用于编排相应的月龄历谱（如金文历谱、某些甲骨文历谱等）;（3）能对月龄历谱（如“夏商周断代工程”给出的西周金文历谱）方案中月龄词语的月龄范围及年代间隔进行误差分析。     

北魏太安至皇兴时期天象记录的年代问题

对《魏书·天象志》中的天象记录进行了统计分析,发现太安至皇兴13年间(457-469)的连续62条可以计算验证的天象记录中,有59条记录的年份都恰好提前了一年.这可能是魏志抄宋志而于年代比对发生错误,也可能是北魏纪年本身的错误.     

Study of the varve record from Erlongwan maar lake, NE China, over the last 13 ka BP

In a sediment sequence from Erlongwan maar lake that spans the last 13 ka BP, two main varve types can be recognized: biogenic varves (from the present to ~11.2 ka BP, 0―632 cm) and clastic varves (from ~11.2 to ~12.7 ka BP, 632―700 cm). Based on the dominant types of algae contained in the sediment, the biogenic varves can be classified into dinocyst-biogenic varves (0―63 cm) and mixed (dinocyst and diatom)-biogenic varves (214―632 cm). In this paper, the formation process and com- ponents of the varve are described, the possible reason for the types of varve changing throughout the record is discussed and a high-resolution varve chronology is established spanning the last 13 ka BP. Although further varve counting and error assessment are needed, the results presented here repre- sent a solid foundation for studying the palaeoclimate record of Erlongwan maar lake.     

夏商周断代工程中的几个天文学问题

《夏商周断代工程》得到的年代结果中,有些与天文学方法有关.本文介绍4个这样的问题:对宾组卜辞的5次月食记录的天文学认证与武丁王年,与武王伐纣有关的诸多天象历日记录的分析,竹书纪年中"懿王元年天在旦于郑"的日食说研究以及由西周铜器铭文中的诸多历日月相记录排出整个西周王年.     

Climate change over southern Qinghai Plateau in the past 500 years recorded in Sabina tibetica tree rings

Two tree ring-width chronologies of Sabina tibetica were developed based on cores sampled in Qumalal and Zhiduo, southern Qinghai Plateau. The response function analysis showed that the chronologies were sensitive to temperature and precipitation from April to June in the plateau. Moisture index (MI) was defined, reconstructed and extended back to AD 1550. The cross-validation method was used to check the stability of the calibration equation, and the result indicated that the equation was stable. Six severe dry periods were found in this region in the past 453-year reconstruction, which were 1592 to 1610, 1649 to 1665, 1687 to 1697, 1740 to 1750, 1818 to 1829 and 1918 to 1933. Five severe wetting periods were 1669 to 1682, 1700 to 1709, 1800 to 1814, 1898 to 1909 and 1935 to 1950. Spectrum analysis indicated that there existed long-term cycles of 60.4 and 53.4 a, solar cycle of 11 a and short-term cycles of 8, 6 and 4 a in the reconstructed series.     

Newly discovered Palaeolithic artefacts from loess deposits and their ages in Lantian,central China

Eight new Palaeolithic open-air sites were identified and 770 stone artefacts were collected from 2009 to 2011 in the Lantian area of the Bahe River valley, central China. Because the famous Homo erectus fossils were unearthed at the Gongwangling and Chenjiawo localities, and more than 30 Palaeolithic open-air sites were investigated in the 1960s in this region, the catchment of Bahe River is regarded as one of the most important hominin sites from the late early Pleistocene to the middle Pleistocene. These eight newly discovered open-air sites are located at the second(n = 6), third(n = 1) or higher terraces(n = 1) of the Bahe River. The Diaozhai section on the second terrace was sampled in detail. Two samples were collected for optically stimulated luminescence dating(OSL). The OSL results suggest that a buried lithic artefact layer at the Diaozhai site spans approximately 70–30 ka. The lithic assemblage analysis suggests that the stone artefacts were made of local pebbles/cobbles such as greywacke, quartz, sandstone and igneous rocks. The main percussion techniques that were used were direct hard hammer percussion and bi-polar techniques. The lithic artefacts comprise hammer stones, cores, flakes, retouched tools and flaking debris. Acheulian-type large cutting tools(LCTs) such as hand-axes, picks and cleavers were indentified in the Lantian region as well. This is the first time Acheulian-type LCTs from the late Pleistocene have been identified in this region. This study distinguishes age gaps between Western world and East Asian Acheulian-type tools.