坝上草原相关花粉源范围与相对花粉产量估算

基于坝上草原地区30个采样点表土花粉分析和植被调查的研究结果显示, 花粉组合以蒿属、藜科、禾本科、菊科和莎草科等草本植物为主, 基本能够反映草原植被特征, 但花粉百分比与其在植被中盖度差异明显。运用Extended R-Value(ERV)模型估算的坝上草原区相关花粉源范围大致为2100m, 当风速大于3.5m/s时, 基本稳定, 受风速影响不大。估算的相对花粉产量结果显示, 蒿属和藜科的相对花粉产量最高, 为禾本科的20倍左右; 其次为莎草科和菊科, 为禾本科的7~9倍; 百合科略高于禾本科; 旋花科、豆科、唇形科及委陵菜属的相对花粉产量则明显低于禾本科。利用相对花粉产量对花粉与植被关系的校正结果表明: 蒿属、藜科的校正效果明显, 其相对花粉产量可以作为定量重建古植被的参考; 莎草科、菊科、百合科和唇形科由于受植被和花粉数据梯度限制, 其相对花粉产量能否用于植被与花粉关系的校正有待通过更多植被群落调查进一步证实;其他花粉类型由于在花粉组合中含量多低于5 %, 所以在校正花粉与植被关系时的作用不明显。     

The geobiological formation process of the marine source rocks in the Middle Permian Chihsia Formation of South China

The Chihsia Formation is one of the four sets of regional marine hydrocarbon source rocks from South China.In the past two decades,detailed geochemical and sedimentological studies have been carried out to investigate its origination,which have demonstrated that the high primary productivity plays a primary role in the deposition of sediments enriched in the organic matter.However,the mechanism of this high productivity and the path of the deposition and burial of the organic matter have always been a mystery.Based on the previous studies on the Shangsi Section in Guangyuan City,Sichuan Province,we proposed that the development of the equatorial upwelling due to the sea level rise is responsible for the relatively high productivity in the Chihsia Formation.The sea waters with high nutrient were transported by the sub-surface currents along the equator.High organic carbon flux was deposited on the deeper shelf,and then decomposed by bacteria,leading to the occurrence of anaerobic respiration.The metabolism of the microorganisms consumed the dissolved oxygen in waters,which was in favor of the preservation of the organic matter.This suggested geobiological model integrating with paleoclimatology,paleoceanography and geomicrobiology will help us to understand the causes of this particular sedimentary sequence.     

云南保山金厂河铁铜铅锌多金属矿床S-Pb同位素特征

滇西金厂河铁铜铅锌多金属矿床位于云南省保山地块北部、NS向保山—施甸复背斜与NNW向澜沧江断裂的锐角交汇部位的南部。文章在以往工作的基础上,研究金厂河铁铜铅锌多金属矿床的S-Pb同位素特征,这对分析该矿床成矿物质来源及探究成矿过程具有十分重要的意义。采样及测试结果显示,该矿床硫化物的δ³⁴S值为+2.5‰~+11.1‰,平均+5.65‰,说明矿床硫化物硫的来源为深部幔源岩浆硫和混合硫（复杂硫）;共生含硫矿物中富集δ³⁴S的均值为：黄铜矿（+5.65‰） > 闪锌矿（+5.38‰） > 方铅矿（+3.45‰）,表明矿床硫同位素分馏未达到平衡。²⁰⁷Pb/²⁰⁴Pb—²⁰⁶Pb/²⁰⁴Pb、²⁰⁸Pb/²⁰⁴Pb—²⁰⁶Pb/²⁰⁴Pb铅同位素模式图中样品点分布位置及朱炳泉Δβ—Δγ变化范围图解结果表明,该矿床铅同位素主要来源于上地壳,此外和深部岩浆的侵入活动相关。     

Model study of the relationship between sediment yield and river basin area

The SHETRAN physically based, spatially distributed model is used to investigate the scaling relationship linking specific sediment yield to river basin area, for two contrasting topographies of upland and more homogeneous terrain and as a function of sediment source, land use and rainfall distribution. Modelling enables the effects of the controls to be examined on a systematic basis, while avoiding the difficulties associated with the use of field data (which include limited data, lack of measurements for nested basins and inability to isolate the effects of individual controls). Conventionally sediment yield is held to decrease as basin area increases, as the river network becomes more remote from the headwater sediment sources (an inverse relationship). However, recent studies have reported the opposite variation, depending on the river basin characteristics. The simulation results are consistent with these studies. If the sediment is supplied solely from hillslope erosion (no channel bank erosion) then, with uniform land use, sediment yield either decreases or is constant as area increases. The downstream decrease is accentuated if rainfall (and thence erosion) is higher in the headwaters than at lower elevations. Introducing a non‐uniform land use (e.g. forest at higher elevations, wheat at lower elevations) can reverse the trend, so that sediment yield increases downstream. If the sediment is supplied solely from bank erosion (no hillslope erosion), the sediment yield increases downstream for all conditions. The sediment yield/basin area relationship can thus be inverse or direct, depending on basin characteristics. There still remains, therefore, considerable scope for defining a universal scaling law for sediment yield. Copyright © 2006 John Wiley & Sons, Ltd.     

青岛市秋冬季霾期PM1及其含碳组分理化特征及来源研究

对2017年11月1日—2018年1月31日与2018年11月1日—2019年1月31日连续两年青岛市大气PM₁进行监测,获取了PM₁中含碳组分的变化趋势,结合国控站点监测数据和气象条件,分析了秋冬季PM₁来源.结果表明：2017、2018年秋冬季观测期间PM₁日均质量浓度分别为40.58±25.98、42.55±25.05 μg/m³;霾日质量浓度分别为84.71±16.70、81.52±18.39 μg/m³.与2017年相比,2018年同期PM₁质量浓度增长4.85%,霾日下降3.76%.2017年霾日PM₁中OC、EC质量浓度分别为13.67±3.95、3.95±1.02 μg/m³,2018年分别为16.48±6.34、3.34±1.16 μg/m³.与2017年相比,2018年霾日OC质量浓度增长20.56%,EC下降15.44%.2017、2018年霾日SOC质量浓度分别是非霾日的1.28和2.15倍,表明霾污染发生时易发生有机碳二次转化.含碳组分主成分分析均解析出3个因子.因子1解释变量均最大,分别为58.98%、67.14%,其表征含碳组分主要源于生物质燃烧、燃煤、道路扬尘及汽油车尾气等排放源.由后向气流轨迹分析得出,2017、2018年秋冬季气团轨迹多起源于内蒙古,经河北、天津、山东等省市抵达青岛.     

油气初次运移理论新探

应用渗流力学的基本原理,研究油气初次运移的机制问题。研究认为,油气的初次运移是以连续相、而不是以溶液相和扩散相的形式进行的;油气初次运移的动力是浮力,因而初次运移的方向是向上的;油气初次运移所需的时间与源岩的渗透能力有关,与油气的粘度有关,还与源岩的厚度有关;油气藏的异常高压是一种暂时的压力状态,气藏的异常高压多于油藏,新生油气藏多于古油气藏;油气初次运移的通道就是源岩的粒间孔隙,源岩的非均质性和微裂缝对油气初次运移十分不利,因形成微油气藏而降低油气运移效率;源岩的厚度越大,越有利于油气聚集;“倒灌”现象是不存在的,缺少基本的动力驱动,基岩油气藏的形成是二次运移过程中侧向运移的结果。初次运移与二次运移具有相同的动力机制、运移相态和运移方向,因而两者是完全统一的。     

大兴安岭南部地区林西组油气勘探前景探讨

基于露头资料,利用有机地球化学分析技术,通过研究大兴安岭南部林西组地层及烃源岩发育特征,探讨有利勘探方向.结果表明：大兴安岭南部地区上二叠统林西组广泛发育,其沉积环境主体为三角洲-湖相沉积;林西组暗色泥岩有机质含量以中等为主,有机质类型为Ⅱ2~Ⅲ型,有机质热演化达到高熟-过熟阶段.该区开展油气勘探应远离侵入岩发育区,在有中生界覆盖地区,保存条件及盖层条件更为有利.     

Lead isotope geochemical characteristics of Pb-Zn-Cu deposits on the southwestern margin of Tarim, and their significance

The polymetallic(Pb,Zn,Cu,etc) ore belt on the southwestern margin of Tarim is one of the major regions with the greatest prospecting potential in Xinjiang.Reported in this paper are the lead isotope data for 66 sulfide samples(including 50 galena samples,15 chalcopyrite samples and 1 pyrite sample) collected from such representative deposits as Tamu,Tiekelike,Kalangu,Abalieke,etc.in this ore belt.The Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb in the galena samples range from 17.931 to 18.176,15.609 to 15.818 and 38.197 to 38.944,with the average values of 18.017,15.684 and 38.462,respectively.Those in the chalcopyrite samples range from 17.926 to 18.144,15.598 to 15.628 and 38.171 to 38.583,with the average values of 18.020,15.606 and 38.262,respectively.The pyrite sample has the Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb to be 17.980,15.604 and 38.145,respectively.In combination with the previous Pb isotope data for sulfides,it is found that there is only a slight variation in the Pb isotopic composition of galena,chalcopyrite,sphalerite and pyrite in the ore belt.However,there is some difference in Pb isotopic characteristics between galena and chalcopyrite,especially the Pb isotopic composition of galena shows an obvious linear correlation with some other relevant parameters(e.g.β and γ).The comprehensive analysis suggested that lead in galena(maybe including sphalerite and pyrite) was derived principally from wall rocks and underlying basement,and that in chalcopyrite only originated from the basement.The single-stage model ages of these sulfides couldn’t indicate the time limit of metallogenesis(Pb,Zn,Cu,etc.),and the positive linear correlations for the Pb isotopic composition of galena are of no single-stage and two-stage Pb-Pb isochron significance.Furthermore,there are significant differences in Pb isotopic composition characteristics between the genetic type of deposits in this polymetallic ore belt and the Mississippi Valley type(MVT).In addition,the authors also pointed out that there is a phenomenon of differentiation(not paragenesis) for lead and copper elements during the process of metallogenesis in this ore belt.     

银额盆地哈日凹陷油气成藏条件及成藏模式

近年来,银额盆地哈日凹陷的油气勘探呈现出良好的态势,但对于哈日凹陷油气成藏条件相关研究甚少,已不能满足目前油气勘探开发的需求。本研究基于钻录井、地球物理、分析化验等资料,系统分析哈日凹陷油气成藏的烃源岩、储层、圈闭等条件,总结油气成藏条件配置关系,以期为哈日凹陷的后续油气勘探及地质研究提供依据。哈日凹陷主要发育三套烃源岩,其中银根组烃源岩有机质丰度极高,成熟度较低,有机质类型为Ⅰ-Ⅱ1型;巴二段烃源岩有机质丰度较高,成熟-高成熟,有机质类型为Ⅱ1-Ⅱ2型;巴一段烃源岩有机质丰度中等,成熟-高成熟,有机质类型为Ⅱ1-Ⅱ2型。储层类型为砂（砾）岩常规储层、碳酸质泥岩非常规储层和火山岩储层,且均属于特低孔超低渗储层,其中砂、砾岩储层和灰质泥岩储层物性最好,白云岩储层和火成岩储层次之,目前主力油藏主要集中在砂、砾岩储层和灰质泥岩储层这两种类型中。哈日凹陷主要发育两套岩性圈闭,即巴一段砂岩岩性圈闭和巴二段泥岩岩性圈闭,形成了源内（准）连续成藏模式和近源不连续成藏模式。     

芦山地震有限断层混合震源模型模拟

建立了基于有限断层的芦山地震的混合震源模型,突出破裂面上滑动量分布中凹凸体的主导作用,同时借助k平方模型表达对震源复杂性认识尚不够深入所带来的随机性.混合震源模型中全局震源参数均值与局部震源参数均值的确定,主要依据统计的半经验标定公式,进一步借助截断正态分布将区域地震、地质构造、地震活动性提供的参数限值结合起来,生成最终的震源参数值.基于上述思路,本文共建立了30组芦山地震混合震源模型,进而以芦山地震8个近场观测台站为试算点,借助地震动反应谱残差评价的方法,从30组模型中选定了表达“平均”特征的混合震源模型.