Near-vertical seismic reflection image using a novel acquisition technique across the Vrancea Zone and Foscani Basin, south-eastern Carpathians (Romania)

The DACIA PLAN (Danube and Carpathian Integrated Action on Process in the Lithosphere and Neotectonics) deep seismic sounding survey was performed in August–September 2001 in south-eastern Romania, at the same time as the regional deep refraction seismic survey VRANCEA 2001. The main goal of the experiment was to obtain new information on the deep structure of the external Carpathians nappes and the architecture of Tertiary/Quaternary basins developed within and adjacent to the seismically-active Vrancea zone, including the Focsani Basin. The seismic reflection line had a WNW–ESE orientation, running from internal East Carpathians units, across the mountainous south-eastern Carpathians, and the foreland Focsani Basin towards the Danube Delta. There were 131 shot points along the profile, with about 1 km spacing, and data were recorded with stand-alone RefTek-125s (also known as “Texans”), supplied by the University Texas at El Paso and the PASSCAL Institute. The entire line was recorded in three deployments, using about 340 receivers in the first deployment and 640 receivers in each of the other two deployments. The resulting deep seismic reflection stacks, processed to 20 s along the entire profile and to 10 s in the eastern Focsani Basin, are presented here. The regional architecture of the latter, interpreted in the context of abundant independent constraint from exploration seismic and subsurface data, is well imaged. Image quality within and beneath the thrust belt is of much poorer quality. Nevertheless, there is good evidence to suggest that a thick (10 km) sedimentary basin having the structure of a graben and of indeterminate age underlies the westernmost part of the Focsani Basin, in the depth range 10–25 km. Most of the crustal depth seismicity observed in the Vrancea zone (as opposed to the more intense upper mantle seismicity) appears to be associated with this sedimentary basin. The sedimentary successions within this basin and other horizons visible further to the west, beneath the Carpathian nappes, suggest that the geometry of the Neogene and recent uplift observed in the Vrancea zone, likely coupled with contemporaneous rapid subsidence in the foreland, is detached from deeper levels of the crust at about 10 km depth. The Moho lies at a depth of about 40 km along the profile, its poor expression in the reflection stack being strengthened by independent estimates from the refraction data. Given the apparent thickness of the (meta)sedimentary supracrustal units, the crystalline crust beneath this area is quite thin (< 20 km) supporting the hypothesis that there may have been delamination of (lower) continental crust in this area involved in the evolution of the seismic Vrancea zone.     

基于Markov chain理论的科技成果转化的市场预测

科技成果成功转化的主要标志是其产品的市场畅销度。产品的畅销度由于受各种内外部不确定因素影响，具有随机不确定性。基于这种随机不确定性，运用Markov chain对其产品进行市场预测，并通过实证分析说明其有效性，为科技成果的转化提供具体可行的定量依据。     

The Early Cretaceous Jacuí Group,a newly discovered volcaniclastic–epiclastic accumulation at the top of the Paraná Basin,southern Brazil

The presence of volcaniclastic rocks related to the silicic magmatism within the Serra Geral Formation has been a matter of long-standing debate. In this paper, we present extensive documentation that supports the presence and abundance of these rocks in the Jacuí Group, a newly discovered volcaniclastic and epiclastic accumulation in southern Brazil. The Jacuí Group is composed of two interfingered stratigraphic units, the Volta Alegre and Tupanciretã formations, and it represents the uppermost stratigraphic unit of the Paraná Basin. The Volta Alegre Formation is primarily composed of resedimented volcaniclastic tuffites, the pyroclasts which were sourced from the Santa Maria subgroup of the Palmas-type of the Serra Geral Formation. The Tupanciretã Formation is composed of fluvial and aeolian deposits transported towards the north–northwest. Deposition of the Jacuí Group began in the Early Cretaceous (∼132 Ma) and was coeval with the acidic volcanism of the Santa Maria subgroup. This group was deposited in a probable interior sag basin that represents either the beginning of the extension in the inner part of the continent that subsequently migrated to the east or the far-field impact of extensional processes that preceded the break-up of Gondwana and the opening of the South Atlantic Ocean.     

基于均一化资料的中国大陆极端温度的长期趋势

近百年来,全球气候变暖。这与暖日和暖夜增加,冷日和冷夜减少相关联。文章研究结果进一步证实了这一发现。本文基于1960-2012年中国大陆542个台站均一化气温资料,通过将中国大陆划分为8个次区域,利用百分位定义法计算了极端温度指数序列,同时,运用时间趋势分析法,对中国大陆各区域极端温度和极端温度指数的时空分布及变化趋势特征进行了分析。结果表明:在全球变暖的背景下,从地理分布而言,中国大陆在过去53年除西南地区外,大部分地区最低和最高温度有显著的升高趋势,其中,东北温度升高最为明显;从季节而言,冬季极端温度升高最为明显,夏季升高最少;最低温度明显升高,最高温度也有所升高,但是最低温度的升高幅度更大。冷夜和冷日出现频率呈减少趋势,暖夜和暖日出现频率呈增加趋势,其中以冷夜指数变化最为突出,均呈现一种区域差异的现象。本文利用更新的资料验证了前人的工作,也进一步分区分析,结果可为更多地区评估以及进一步的相关研究提供参考。     

苏鲁超高压变质带超镁铁岩深部碳酸盐交代作用的证据

中国大陆科学钻探工程第三先导孔(PP3钻孔),位于秦岭-大别-苏鲁超高压造山带的东部,赣榆岗上超镁铁岩体中。钻孔中超镁铁岩的岩性包括纯橄岩和石榴超镁铁岩等,该超镁铁岩的SiO_2含量均值在43.68%,变化范围为41.9%~47.11%;MgO均值在44.71%,变化范围为47.12%~48.62%;Cr_2O_3均值在0.39%,变化范围为0.30%~0.47%;CaO均值0.12%(变化范围为0.006%~0.34%);Na2O均值在0.05%(变化范围为0.005%~0.32%)。超镁铁质岩的Mg#(Mg/(Mg+Fe)×100)稳定在91.9~93.0之间,Cr#(Cr/(Cr+Fe)×100)均值在38,较高;变化在30~45之间,变化小。其中闪石化金云母超镁铁岩具有最低的值(Cr#=19)。Ni含量在2100×10~(-6)~2500×10~(-6),CaO含量均值为0.13%,Al_2O_3含量均值为0.41%。岩体成分均一,表现为高镁,低钙和低铝的特征。超镁铁岩的不相容元素和稀土元素总量很低,稀土元素总量均值在0.60×10~(-6)。(La/Yb)N比值在6.9~51.2,均值在16.1,重稀土元素严重亏损,是中国东部最亏损的地幔岩之一。超镁铁岩中橄榄石成分(Fo在88.7~93.1之间,Fa在6.8~11.1之间),从早期到晚期,岩石Fo值从93→91~92.4→88.7~89.1。铬尖晶石Cr#值从51到89变化,TiO_2和MnO_2值分别低于0.26%和0.46%,晚期铬尖晶石Cr#值增大,Ti含量减小。单斜辉石由透辉石(Wo_(45.9)8En_(47.89)Fs_(2.73)Ac_(3.39))和顽透辉石(Wo_(27.61)En_(68.78)Fs_(2.27)Ac_(1.34))两种,透辉石(Cpx_Ⅰ)在顽透辉石(Cpx_Ⅱ)中呈被交代的残余粒状。角闪石和金云母呈明显的条带状和脉状,局部发育。岩石具有弱的Na和K交代作用,较高的Sr和Ba等元素,亏损高场强元素(HSFE),以及特征的稀土元素和微量元素配分曲线;岩石中主要组成矿物橄榄石从早期到晚期,矿物Mg#指数下降(Mg#从93→88);单斜辉石中可看到透辉石被顽透辉石交代现象;次生角闪石和金云母的形成等特征都显示超镁铁岩经历了碳酸盐交代作用。在超镁铁岩矿物橄榄石中发现细小白云石和菱镁矿等碳酸盐矿物更有力证明了苏鲁超高压变质带超镁铁岩经历了深部碳酸盐交代作用。PP3钻孔超镁铁岩属于强烈亏损地幔岩区域,单斜辉石和角闪石等含水矿物在超镁铁岩中含量低,交代作用的范围和规模有限,且交代作用在动力学上是快速的和不平衡的过程。     

纪念中国大陆科学钻探实施15周年、国际大陆科学钻探委员会成立20周年

大陆科学钻探是“入地”的重要手段,是“深入地球内部的望远镜”。中国大陆科学钻探事业开展15周年以来,取得重要进展,获得全球地学界的高度关注,特别是2001年实施的中国第一口大陆科学深钻 （5158m）,成果辉煌,影响巨大。继后,又开展了青海湖环境科学钻探、松辽盆地白垩纪科学钻探、柴达木盐湖环境资源科学钻探,汶川地震断裂带科学钻探以及中国大陆科钻资源集成计划,总共钻进约 35km,显示了中国科学钻探方兴未艾的景象。为纪念国际大陆科学钻探20周年（1996~2016）和中国大陆科学钻探实施15周年（2001~2016）,本文回顾中国大陆科学钻探实施15年来的艰辛和奋斗的历程,展望中国大陆科学钻探的未来。     

Geochemistry of Paraná-Etendeka basalts from Misiones,Argentina: Some new insights into the petrogenesis of high-Ti continental flood basalts

The Early Cretaceous (∼135–131 Ma) Paraná-Etendeka continental flood basalts, preserved in bulk in the Paraná basin of southern Brazil and vicinity, have been divided into low-Ti and high-Ti types that govern the southern and northern halves of the basin, respectively. We have examined a new sample set from the southern margin of the northern high-Ti segment of Paraná basalts in Misiones, northeastern Argentina. These basalts are strongly to moderately enriched in TiO₂ (2–4 wt.%), have relatively high Ti/Y (300–500), low MgO (3.5–6.5 wt.%), and high Fe (FeO(tot) 12–14 wt.%) and belong to the Pitanga and Paranapanema magma types of Peate et al. (1992). Nd and Sr isotope compositions are quite unvarying with ε_Nd (at 133 Ma) values of −4.6 to −3.6 and initial ⁸⁷Sr/⁸⁶Sr of 0.7054–0.7059 and show no variation with fractionation. Compared to high-Ti lavas in the central and northern parts of the Paraná high-Ti basalt segment, the lavas from Misiones are similar to those in the northeastern magin of the basin but less radiogenic in initial Nd isotope composition than those in the central part. This variation probably reflects mixed EM1-EM2 source components in the sublithospheric mantle. A polybaric melt model of a sublithospheric mantle source at the garnet lherzolite-spinel lherzolite transition is compatible with the observed Ti budget of the Pitanga and Paranapanema lavas, regardless of the Nd isotope composition of their purported source.     

WFSD-4S孔流体地球化学特征

本文开展汶川地震断裂带科学钻探现场流体研究,探讨了泥浆添加剂产生的化学反应以及钻孔中岩性变化引起的流体异常特征,并在排除这些影响因素的情况下,讨论地震期间流体的异常。研究表明在WFSD-4S钻进期间发生的两次较大地震前均伴有Rn、Ar、N2和O2等气体异常现象,其中氡的日均值均超出背景值的2.5倍。根据岩心观察得到WFSD-4S钻井地区主断层约在1084 m,而在断层之上931 m处开始出现了大量气体的高值异常,该异常可能是由于地震孕育过程中地下气体的运移通道被打开造成气体向上迁移,使断层气体的响应特征提前发生。     

Emerging Chinese Cities: Implications for Global Urban Studies

Chinese cities are emerging in multiple senses: They have created new physical spaces to accommodate the fast urbanization of the country but have also developed new properties and characteristics along with urban transformation. The novelty created by emerging cities in China is not easily covered by Western urban theory. This article examines the dynamism of Chinese urban transformation, especially political economic changes vis-à-vis so-called neoliberalism, and spatial outcomes as diverse and contrasting spaces of formality and informality. Finally, this article speculates on implications for global urban studies.     

基于LabView的松科2井项目管理系统

松科二井2013年正式启动,2018年5月完井,历时6年,最终井深7018 m。项目执行过程中,形成合同700多个、文件200多个、汇款流水1000多笔、报账流水1600多笔。针对松科二井合同、文件繁多,财务流程繁杂,涉及项目多的特点,基于LabVIEW平台设计了一套项目管理系统。该系统可全程记录松科二井上述合同、文件、汇款和报账信息,建立合同及对应批次汇款和报销的勾稽关系,具有模糊查询、修改、超链接等功能。