珠-坳陷湖盆古环境恢复与优质烃源岩发育模式

珠-坳陷古近纪陆相湖盆发育优质烃源岩,通过对文昌组、恩平组泥岩系统取样,进行常量、微量元素、同位素含量等分析,优选出对环境敏感的元素与元素比值,系统分析了珠-坳陷烃源岩形成时的古环境,包括古盐度、古水深、氧化还原条件、古气候及古水体的封闭性,并建立了有机碳与环境敏感元素比值的定量关系。开展优质烃源岩发育的水化学性质研究,明确研究区优质烃源岩形成演化所具有的古环境特征,最终探讨了文昌组优质烃源岩的发育模式。研究结果表明,珠-坳陷(除韩江凹陷无样本点)文昌期温暖略干气候条件下,湖盆水体主要为淡水-微咸水,发育中-深湖相,整体表现为开放-半封闭、还原—强还原的环境,极利于有机质的保存和优质烃源岩的发育,各凹陷古环境差异不大。烃源岩质量与咸度、水深、还原条件呈正相关,共同影响了优质烃源岩的发育。总之,温暖略干、微咸、深水及强还原、开放-半封闭环境共同控制了珠-坳陷优质烃源岩的发育。     

基于网络药理学与分子对接研究肉豆蔻治疗抑郁症的作用机制

目的：基于网络药理学方法与分子对接技术研究肉豆蔻治疗抑郁症的作用机制。方法：通过中药系统药理学分析平台TCMSP,获得肉豆蔻的活性成分和作用靶点;利用Uniprot数据库构建中药-成分-靶点网络;从GeneCards、OMIM、DrugBank数据库获得抑郁症疾病靶点、肉豆蔻及抑郁症共有靶点;通过Venny 2.1.0平台、String平台进行肉豆蔻与抑郁症共同靶点相互作用分析;利用Cytoscape 3.7.2软件构建蛋白互作（PPI）网络,采用Metascape平台对核心靶点进行基因本体（GO）功能及京都基因与基因组百科全书（KEGG）通路富集分析;采用分子对接技术确定肉豆蔻有效成分作用于抑郁症的核心靶点。结果：获得42个潜在作用靶点。乙酰胆碱酯酶（ACHE）、钠依赖性血清素转运体（SLC6A4）、一氧化氮合酶（NOS3）、Alpha-2A肾上腺素能受体（ADRA2A）可能是肉豆蔻治疗抑郁症的核心基因。肉豆蔻作用于抑郁症的通路涉及神经受体相互作用、钙信号通路。分子对接技术验证了肉豆蔻有效成分中的β-谷甾醇与潜在靶点ACHE和NOS3具有较好的结合活性。结论：肉豆蔻的主要活性成分β-谷甾醇可能通过作用于ACHE等多个靶点来调控神经受体相互作用、钙信号通路等多条信号通路,从而发挥抗抑郁作用。     

Land cover controls on depression‐focused recharge on the Oak Ridges Moraine,southern Ontario,Canada

The Oak Ridges Moraine (ORM) is a key hydrogeologic feature in southern Ontario. Previous research has emphasized the importance of depression‐focused recharge (DFR) for the timing and location of water recharge to the ORM's aquifers. However, the significance of DFR has not been empirically demonstrated, and the ORM's permeable surficial deposits imply that rainfall and snowmelt will largely recharge vertically rather than move laterally to topographic depressions. The exception may be during winter and spring, when concrete soil frost limits infiltration and encourages overland flow. The potential for DFR was examined for closed depressions under forest and agricultural land covers with similar soils and surficial geology. Air temperatures, precipitation, snow depth and water equivalent, soil water contents, soil freezing, and depression surface‐water levels were monitored during the winter and spring of 2012–2013 and 2013–2014. Recharge (R) was estimated at the crest and base of each depression using a 1‐dimensional water balance approach and surface‐applied Br^? tracing. Both forest and agricultural land covers experienced soil freezing; however, forest soils did not develop concrete frost. Conversely, agricultural fields saw concrete frost, overland flow, episodic ponding, and subsequent drainage of rain‐on‐snow and snowmelt inputs in open depressions. Recharge at the base of open depressions exceeded that in surrounding areas by an order of magnitude, suggesting that DFR is a significant hydrologic process during winter and spring under agricultural land cover on the ORM. Closed topographic depressions under agricultural land cover on the ORM crest may serve as critical recharge “hot spots” during winter and spring, and the ability of the unsaturated zone beneath these depressions to modify the chemistry of recharging water deserves further attention.     

Effects of ultrafiltration on salt migration and isotopic composition of pore water in groundwater depression area in Hengshui,NCP

Clay aquitards are semipermeable membranes that allow groundwater flow while retarding solute migration has been researched extensively but also subjected to much debate. At present, there is no evidence of whether the physical and chemical properties of clay soil and the isotopic composition of pore water affect the semipermeable membrane effect. In this study, we collected clay samples from drilling cores (30–90 m) in the Hengshui area located in the North China Plain (NCP), then extracted pore water using a high-pressure squeezing device. Vertical hydrochemical and isotopic profile variation trends for the pore water were revealed using hydrochemical (Cl⁻, Na⁺, Ca²⁺, K⁺, Mg²⁺, and SO₄²⁻) and stable isotopic measurements of H, O and Cl. The results showed that the hydrochemical clay interlayer pore water of the saline aquifer is Cl/SO₄-Na/Mg type and the average total dissolved solids (TDS) are 10.17 g/L. However, the hydrochemical clay aquitard pore water is of the Cl/SO₄-Na/Ca type with an average TDS of 1.90 g/L. The hydrochemical clay interlayer pore water of aquifer II is of Cl-Na/Ca type with an average TDS of 1.10 g/L. Our results showed that the water quality of the aquifer II is not affected by the upper part of the saline aquifer, thus the clay aquitard acts as a significant barrier to salt movement. A polarization layer concentrated in ions was formed between the upper part of the saline aquifer and the clay aquitard. The concentration polarization layer increases the salt-inhibition effect. H, O and Cl isotopic composition results showed significant fractionation. The pore water of aquifer II lacked heavy isotopes (²H, ¹⁸O, ³⁷Cl), but had significant heavy isotope enrichment in the concentrated polarized layer (the δ²H value was −76‰, the δ¹⁸O value was −8.4‰, and the δ³⁷Cl value was 1.59‰). Hyperfiltration thus played a significant role in isotope fractionation.     

滇东南丘北区峰丛—洼地地貌形态特征分析

云贵高原东南部丘北区为峰丛—洼地岩溶组合地貌。利用统计分析方法考察了该区48个岩溶洼地及峰体的形态参数特征;利用分形理论方法计算了不同高程的等高线和地表水系的分维数。结果表明:（1）洼地的平均边数为5.6,平均周长3.4km,平均面积0.8km2;（2）洼地的加深和扩大近于同步,原始地面对后期溶蚀面的发育起控制作用;（3）峰丛—洼地的形态分形特征对岩溶演化具有很好的响应关系,可溶岩区等高线分维数平均为1.30,非可溶岩区为1.16,地表水文网分维数为1.07,反映岩溶区地形变化复杂,地下水文网较发育,岩溶发育程度较高;（4）研究区岩溶发育仍处于幼年至壮年期,将继续缓慢发育。      

南海北部深水盆地浅水流的地球物理特性及识别

浅水流(Shallow Water Flow,SWF)是深水环境海底浅部地层中超压的砂体流动,是对深水钻井最具破坏力的一种地质灾害,严重制约深水油气开发.为有效预测和防治浅水流,需要对浅水流地球物理特性进行研究,并在研究区内加以识别.本文借鉴国外主要深水盆地对浅水流问题的研究经验,对南海北部深水盆地潜在浅水流区域采取以属性判定、超压分析为主,振幅识别为辅的方法进行预测.精细层序地层学解释发现,南海北部深水盆地存在上新世以来的古珠江深水水道沉积体系和第四纪水道,这些水道砂体疏松未固结、孔隙度大、有效应力低、几乎表现出流体特性.基于遗传算法的混合反演方法发现,研究区存在典型的AVO响应,横波速度极低,低频特征明显,振幅强度弱,连续性较好,存在极性反转,高泊松比和高纵横波速度比.研究结果表明,南海北部陆坡具备浅水流发生的潜在条件,深水水道发育区为潜在的浅水流危险区,浅水流具有独特的地震响应特征,泊松比高达0.49,纵横波速度比约为3.5~9或更高,SWF层位对地震属性的敏感度V_P/V_S>AVO响应>泊松比.     

渤海湾盆地黄骅坳陷中北区新生代幕式沉降过程

黄骅坳陷中北区是位于渤海湾盆地中部的一个重要新生代构造单元.构造层序界面分析、同生断裂活动和盆地沉降史回剥分析表明该区经历了幕式沉降过程,沉降中心显示出规律性的迁移演化特征.馆陶组底界面为区域性裂后不整合界面,将研究区的演化划分为裂陷期和裂后期.在裂陷期的充填序列中,沙一段底界面为整个研究区都可以识别的显著的角度不整合界面,以此界面为界,盆地的裂陷期进一步划分为裂陷Ⅰ幕和裂陷Ⅱ幕.裂陷Ⅰ幕发育了Es₃-Es₂地层,断裂几何学和断裂的性质表明该幕构造活动为北西南东向伸展作用所致,而裂陷Ⅱ幕发育了Es₁-Ed地层,为近南北向拉伸作用的结果.裂后期,从早到晚则表现为由稳定热沉降到加速沉降的过程.分析认为上述盆地的幕式沉降过程与区域应力场的转变密切相关,受控于周缘板块的动力学事件,尤其是晚始新世之后,太平洋板块对欧亚大陆向西的加速俯冲,促使了郯庐断裂右旋活动向南延伸和穿过黄骅坳陷的兰聊断裂北段的活化,形成了位于渤海海域的南北向伸展叠加区,从根本上改变了黄骅坳陷中北区应力场的分布,由此导致了盆地同裂陷阶段的幕式演化.      

海拉尔盆地乌南凹陷下白垩统沉积充填演化及构造控制

通过层序界面的识别和划分,乌南凹陷下白垩统可划分为5个二级层序,7个三级层序。以断裂坡折带为界,乌南凹陷可划分为西缘陡坡带、东缘斜坡带、乌南次洼带、乌中低凸起、巴彦塔拉断裂带等次级构造单元,各次级构造单元对沉积体系的发育分布具有重要的控制作用。根据沉降史的分析,下白垩统可划分为裂陷初期、裂陷早期、裂陷中期、断-拗转换期和拗陷期5个构造演化阶段,分别发育火山岩-冲积扇盆地层序、冲积扇-浅湖盆地层序、深湖-半深湖盆地层序、半深湖盆地层序和浅湖盆地层序,各二级层序的发育演化和沉积相构成受构造演化的控制。东缘斜坡带和巴彦塔拉断裂带附近是有利储集相带。     

川西坳陷中段上三叠统须二段气水分布特征及成因机理

川西坳陷深层上三叠统须家河组储层致密化严重,气水分布十分复杂,已经成为制约天然气勘探和开发的关键问题。在对须二段致密气藏地质特征、流体特征和气水分布特征研究的基础上,结合研究区实际地质条件,综合物理模拟实验的结果,揭示了该区复杂的气水分布成因机理。研究结果表明,川西坳陷须二段天然气主要为煤型裂解气,地层水型主要表现为CaCl2型,属于高封闭环境下的地层水。试气资料和测井解释结果表明,川西坳陷深层须二段主要以气层和含气层为主,局部井为气水同层和纯水层,地层水无成层性,水的分布表现出串珠状残留地层水的特点。孤立的地层水不受构造的控制,水的产出并不表现出上水下气或上气下水的特点,由于储层非均质性强,在深盆气形成过程中,气驱替水首先通过相对疏松的高孔高渗的储集空间,而对超致密砂体内已封存完好的水体则无力驱替,形成“残留地层水”,物理模拟实验结果也证实了这一点。     

临清坳陷晚古生代煤成气储层沉积学特征

临清坳陷晚古生代地层是胜利油田勘探的重要层位,研究其煤成气储层特征对该区油气资源勘探和能源接替有重要意义。以沉积学、岩石学和地层学为主要研究手段,在总结该区晚古生代沉积体系及沉积相基础上,分析了山西组和石盒子组等地层中的砂岩储层物性特征。研究发现:该区主要存在四大沉积体系,即潮坪沉积体系、障壁-泻湖沉积体系、河控浅水三角洲沉积体系及河流-湖泊复合沉积体系,其中,三角洲分流河道砂体、大型河流、湖泊及湖泊三角洲沉积砂体成为煤成气的有利储层;这些储层的岩石类型主要有长石砂岩、石英砂岩、岩屑砂岩及硬砂岩等,且石英砂岩以奎山段较发育,长石石英砂岩多发育于山西组。