内蒙古苏莫查干敖包萤石矿区流纹岩锆石SHRIMP定年及地质意义

内蒙古苏查（苏莫查干敖包）萤石矿区晚古生代火山沉积岩分布广泛,主要岩石类型有碳泥质板岩、结晶灰岩、凝灰岩、千枚岩、英安岩和流纹岩,其中碳泥质板岩和流纹岩为苏查特大型萤石矿床的顶和底板围岩。采用锆石SHRIMP UPb铅法分别对底板围岩中蚀变流纹岩和顶板围岩中未蚀变流纹岩样品进行了同位素年代测定,所获数据分别为276±10 Ma和271±8 Ma。蚀变和未蚀变流纹岩的形成时间均为海西晚期（早二叠世）。苏查萤石矿区早二叠世流纹岩是华北陆台与西伯利亚板块从碰撞挤压到松弛张裂转折期,酸性岩浆喷发活动的产物,其成岩物质来自壳、幔混合源。早二叠世流纹岩的出现不仅标志着苏查到西里庙地区海西期构造岩浆活动的终结,同时也为苏查特大型萤石矿床的成矿作用提供了动力、热力和物质来源。早二叠世流纹岩成岩时代的厘定不仅为阐明华北陆台北缘西段构造演化历史提供了科学依据,而且对于查明流纹岩的原岩性质和圈定新的萤石矿床找矿靶区也具有重要意义。     

四川犍为晚侏罗世一新的肉食龙类

记述了四川盆地西南部晚侏罗世上沙溪庙组顶部的中国盗龙型肉食龙类化石材料,并依此建立一新属新种——犍为乐山龙 (Leshansaurus qianweiensis gen. et sp. nov.)。它以上枕骨中嵴呈尖峰状,额骨最大长度与最大宽度之比约2.86,基蝶骨之基翼骨突细长,环椎间椎体马蹄形,背椎横突相当细长,背椎和荐椎神经棘非常薄,荐椎椎体具有明显的腹嵴,肠骨内侧髋臼缘存在一明显的嵴等特征区别于其他肉食龙类。犍为乐山龙是目前所知四川盆地产出层位最高的肉食龙材料,它的发现扩大了肉食龙类的时代分布和地理分布,对探讨肉食龙的演化具有比较重要的意义。     

Distribution and significance of novel low molecular weight sterenes in an immature evaporitic sediment from the Jinxian Sag,North China

An unusual series of C₂₂–C₂₇ monounsaturated sterenes and C₂₄–C₃₀ tetracyclic terpanes (17,21-secohopanes) were detected in relatively high concentrations in an immature evaporitic marl sediment of the Jinxian Sag, Bohai Bay Basin, North China. The site of unsaturation in these novel sterenes is assigned tentatively to the D ring on the basis of mass spectral interpretation, which also distinguishes them from reported unsaturated sterenes. Other hydrocarbon biomarker or stable isotope characteristics are indicative of microbial (e.g. methyl hopanes), phytoplankton or higher plant (depleted δ¹³C values of isoprenoids and hopanes) inputs and an anoxic carbonate depositional environment (hexacyclic hopanes; tetracyclic terpanes). The hydrocarbon composition showed no obvious biodegradation and the relatively high concentration of unsaturated terpenoids (e.g. gammacerene) and low values of other established maturity parameters (T_s/T_m = 0.23; R_o = 0.44%; T_max = 417 °C), are consistent with sediments of low maturity. The novel, low molecular weight sterenes and the tetracyclic terpanes may be early diagenetic products of microbial sources in a carbonate environment.     

钛磁铁矿的制备及其异相Fenton反应催化性能

在水相中合成了钛磁铁矿（Fe3-xTixO4）,并用XRD、MSssbauer、TG-DSC和SEM等手段对合成的Fe3-xTixO4进行了表征。结果表明,合成的Fe3-xTixO4为立方晶系尖晶石结构,样品中的钛离子都已经进入其晶格中;钛掺杂有抑制钛磁铁矿进一步向钛磁赤铁矿转化和稳定尖晶石结构的作用。此外,以亚甲基蓝降解为探针反应,考察了钛磁铁矿异相Fenton反应的催化性能。实验表明,钛含量较高的钛磁铁矿是一种性能优越的异相Fenton反应催化剂。     

深度学习遥感图像标注系统研究

随着深度学习的发展,遥感影像处理技术也从传统机器学习算法向深度学习转变,然而,用于遥感图像的训练数据集却十分稀少,且数据标注困难。本文将GIS技术与图像标注技术相结合,基于Flask Web框架设计一个可用于海量遥感数据的标注系统。该系统可用于海量遥感数据的数据框标注、数据类别标注,以及目标关键点标注,同时能将标注数据导出为深度学习训练最常用的COCO数据集和VOC2007两种格式。     

GeoCube： 面向大规模分析的多源对地观测时空立方体

随着对地立体观测体系的建立,遥感大数据不断累积。传统基于文件、景/幅式的影像组织方式,时空基准不够统一,集中式存储不利于大规模并行分析。对地观测大数据分析仍缺乏一套统一的数据模型与基础设施理论。近年来,数据立方体的研究为对地观测领域大数据分析基础设施提供了前景。基于统一的分析就绪型多维数据模型和集成对地观测数据分析功能,可构建一个基于数据立方的对地观测大数据分析基础设施。因此,本文提出了一个面向大规模分析的多源对地观测时空立方体,相较于现有的数据立方体方法,强调多源数据的统一组织、基于云计算的立方体处理模式以及基于人工智能优化的立方体计算。研究有助于构建时空大数据分析的新框架,同时建立与商业智能领域的数据立方体关联,为时空大数据建立统一的时空组织模型,支持大范围、长时序的快速大规模对地观测数据分析。本文在性能上与开源数据立方做了对比,结果证明提出的多源对地观测时空立方体在处理性能上具有明显优势。     

巨厚灰岩油藏中隔夹层与高渗层成因与发育规律 ——以伊拉克H油田Mishrif组为例

隔夹层和高渗层是影响油田开发效果的重要因素.以伊拉克H油田Mishrif组为例,基于岩心和测井资料,在渗透率控制因素分析的基础上,研究了隔夹层和高渗层的成因类型与发育规律,并探讨了对油田开发的指导意义.Mishrif组生物碎屑灰岩渗透率与岩石结构、孔隙类型和成岩改造密切相关,受沉积和成岩作用的共同控制.隔夹层包括隔层、...     

Discovery of six high-redshift quasars with the Lijiang 2.4 m telescope and the Multiple Mirror Telescope

Quasars with redshifts greater than 4 are rare, and can be used to probe the structure and evolution of the early universe. Here we report the discovery of six new quasars with i-band magnitudes brighter than 19.5 and redshifts between 2.4 and 4.6 from spectroscopy with the Yunnan Faint Object Spectrograph and Camera (YFOSC) at the Lijiang 2.4 m telescope in February, 2012. These quasars are in the list of z > 3.6 quasar candidates selected by using our proposed J K/i Y criterion and the photometric redshift estimations from the SDSS optical and UKIDSS near-IR photometric data. Nine candidates were observed by YFOSC, and five among six new quasars were identified as z > 3.6 quasars. One of the other three objects was identified as a star and the other two were unidentified due to the lower signal-to-noise ratio of their spectra. This is the first time that z > 4 quasars have been discovered using a telescope in China. Thanks to the Chinese Telescope Access Program (TAP), the redshift of 4.6 for one of these quasars was confirmed by the Multiple Mirror Telescope (MMT) Red Channel spectroscopy. The continuum and emission line properties of these six quasars, as well as their central black hole masses and Eddington ratios, were obtained.     

A systematic study on energy dependence of quasi-periodic oscillation frequency in GRS 1915+105

Systematically studying all the RXTE/PCA observations for GRS 1915+105 before November 2010, we have discovered three additional patterns in the relation between Quasi-Periodic Oscillation (QPO) frequency and photon energy, extending earlier outcomes reported by Qu et al. (Astrophys. J. 710:836, 2010). We have confirmed that as QPO frequency increases, the relation evolves from the negative correlation to positive one. The newly discovered patterns provide new constraints on the QPO models.     

2021年青海玛多Ms7.4地震的重力挠曲均衡背景与震前重力变化

本文综合利用EIGEN6C4布格重力异常、SIO V15.1地形和流动重力观测数据,研究2021年玛多Ms7.4地震的重力挠曲均衡背景和震前重力变化特征.首先,基于岩石圈挠曲均衡模型,结合布格重力异常和地形数据,采用有限差分方法计算了震中及周边地区(青藏高原东北部)岩石圈有效弹性厚度(Te)和挠曲均衡重力异常.结果表明,青藏高原东北部Te为0～100 km,横向差异明显,且与块体构造关系密切.巴颜喀拉块体以北的柴达木块体Te值高达50～80 km,以南的羌塘块体大部分区域的Te大于20 km,五道梁以南出现局部大于30 km的高值区,玉树—德格地区出现局部大于40 km的高值区.巴颜喀拉块体Te为0～20 km,较其南北块体明显偏小,更易于发生形变,从而在南北"夹持"下发生物质东向运动,是青藏高原中部物质东流的主要区域.地震易发生在岩石圈强弱变化的过渡地带(Te变化梯度带),以及Te较小区域的断裂带上.本次地震即发生在巴颜喀拉块体内部Te低值区,震中附近有效弹性厚度约为15 km.震前流动重力变化分析表明,2015年以来3～5年的累积重力变化自西向东呈负-正-负的区域性变化特征,大致以震中为界形成了垂直于断裂带的重力变化高梯度带,主要反映了震前青藏高原物质东流过程中出现的深部构造运动态势.2018年以来的重力变化主要呈围绕震中形成西正-东负的弱区域性变化特征,显示震中地区已处于高应力应变的"固化"状态,地震即发生在重力变化零值线拐弯部位.