滠水河流域经济环境协调发展系统动力学模拟

从系统分析的视角出发,根据滠水河流域的自然与社会经济特点,构建经济环境协调发展系统动力学模型,模型主要参数包括人口、GDP、城市化水平、产业结构、水资源可利用量、水环境容量等。通过模型正负反馈环进行因果关系分析,考虑人口、资源、环境与经济之间的互动与制约关系,进行子系统划分,并确定人口平均增长率、服务业废水率、工业废水率以及水土流失率为敏感性因素,以敏感因素为核心,设计3种不同情景,得出经济、环境协调发展情景为最优方案。通过对不同发展情景的分析与比较,提出滠水河流域有必要采取措施控制人口增长,促进经济发展,保护生态环境,实现该流域经济与环境协调发展。     

2022年春季冰雹灾害对贵州西部红心猕猴桃的影响分析

2022年4月下旬至5月上旬,贵州西部共发生了6次冰雹天气过程,有4次冰雹灾害天气严重影响贵州西部红心猕猴桃生产,其主要是发生在4月22日、5月6日、5月8日、5月9日的冰雹天气过程。为了探明2022年4月下旬至5月上旬4次冰雹天气过程对红心猕猴桃果实的影响,通过6次冰雹天气过程影响区的调查,获取冰雹特征数据和红心猕猴桃在4次冰雹灾害过程中的受灾情况,分析诱发冰雹天气发生的大气环流特征,并采用相关统计方法对4次冰雹灾害对红心猕猴桃造成的损失进行评估。结果表明：6次冰雹天气过程中,冰雹最大直径达20mm,但最大直径大多在10mm以下,其中水城区的冰雹最大直径较其他地区大,遭遇冰雹天气次数也最多。影响红心猕猴桃生产的4次冰雹天气过程的天气背景具有贵阳站的CAPE均远远大于威宁站、中低层相对湿度均在90%以上、中高层相对湿度均在80%左右的共同特点。4月22日、5月6日和5月9日冰雹天气发生前,500hPa均有浅槽、700hPa均有低涡切变线入侵贵州西部;5月8日冰雹天气发生前,500hPa和700hPa贵州西部均处于西太副高外围。4次冰雹灾害造成红心猕猴桃885.4hm²绝收,占其基地种植面积的9.04%;因冰雹灾害造成产量损失约1.33万t,直接经济损失19921.5万元。     

江西气候生态产品价值实现的探索与思考

江西省气象部门针对气候生态产品价值实现开展了许多探索,积累了一系列的先进经验。文中从江西气候生态产品价值实现途径、效益、政策等方面进行思考和分析,认为政策先行营造制度环境、创建品牌实现气候价值、试点示范稳步实践创新和搭建平台培育价值理念等手段为挖掘气候好资源做好“两山”转化工作提供了有力支撑。针对发现的问题,提出了建议：理念创新,将气候资源价值转化固化于制;机制创新,用制度保护气候资源价值实现;载体创新,创品牌实现气候生态产品价值。     

2021年秋季江西异常高温天气及环流背景分析

2021年秋季江西出现范围广、强度强、持续时间长的高温天气过程,多项气温指标创历史同期新高,10月1—5日全省仍出现20站次危险性高温天气。利用江西省93个国家气象观测站、MICAPS观测资料以及NCEP/NCAR再分析资料,对此次罕见秋季异常高温天气的过程的特征及环流背景场进行了分析讨论。结果表明：1） 西太平洋副热带高压是江西秋季高温天气的主导系统,强大的副热带高压控制区内盛行的下沉运动产生大气绝热加热是此次秋季异常高温的主要形成原因。同时,西风急流偏强以及南亚高压撤退时间偏晚,使得西风带短波槽脊活动不易影响到副热带地区,有利于副热带高压强度和位置的稳定维持,冷空气难以南下到达长江中下游地区,高温天气得以发展。2） 中低层暖平流输送有利于局地温度升高从而形成高温天气,江西上空对流层异常增温一定程度上加剧了该地区秋季高温的持续。3） 江西境内水汽通量散度呈现负距平,表明水汽辐散程度弱于常年同期,未出现水汽输送的大幅减弱。同时,对流层中下层存在一定的上升气流,部分水汽凝结形成降水。因此,异常高温期间未出现严重干旱。     

Calibration of Vector Magnetograms with the Chromospheric Mg b2 Line

Stokes polarization profiles of the Mg?b₂ 5172.68 Å spectral line on two simple sunspots are obtained with the Multi-Channel Solar Telescope (MCST) at the Huairou Solar Observing Station (HSOS). This is done by means of scanning this line over the wavelength interval from 200 mÅ redward of the line center to 200 mÅ blueward, in steps of 10 mÅ. A generalized analytic solution to the transfer equation for polarized radiation is presented. With a nonlinear least-square fitting technique, the linear calibration coefficients for the low-chromospheric longitudinal magnetic field is obtained in the weak-field case. We also discuss the problems in calibrating the transverse field with this line. It is shown that the weak-field approximation is not applicable to the chromospheric Mg?b₂ line for the transverse component of the magnetic field.     

西藏色布塔铜钼矿床中辉钼矿Re-Os定年及其成矿意义

色布塔铜钼矿床位于冈底斯成矿带北部,具有细脉浸染状矿化,围岩蚀变发育等斑岩型铜钼矿床特征.本文使用电感耦合等离子体质谱仪TJA X-series ICP-MS对色布塔铜钼矿床的花岗斑岩中的辉钼矿进行ReOs同位素定年研究,获得了6件样品的模式年龄为87.52±1.35～88.8±1.26Ma,等时线年龄为88.8±1.5Ma.本文研究成果表明,色布塔铜钼矿成矿时代为晚白垩世早期,属燕山期构造-岩浆活动的产物.     

Geological and thermochronological studies of the Dashui gold deposit, West Qinling Orogen, Central China

The Dashui gold deposit is a structurally controlled, Carlin-type gold deposit hosted by recrystallised limestone in the West Qinling Orogen of Central China. The major, structurally late east-trending Dashui Fault forms the hanging wall to the gold mineralisation at the Dashui mine and defines the contact between Middle Triassic limestone and a steeply dipping overlying succession of Middle Triassic argillaceous limestone, dolomite, and sandstone. Multiple carbonate veins and large-scale supergene enrichment, represented by hematite, goethite, limonite and jarosite, characterise the deposit. Detailed geochronological investigation using zircon SHRIMP U-Pb dating reveals that volcanic rocks closely associated with the Dashui gold deposit were synchronous with the Ge’erkuohe Granite and pre-date mineralisation. The igneous dyke sample from the hanging wall has the same U-Pb zircon age as the footwall, ca. 213 Ma. (U-Th)/He thermochronology on dykes in the hanging wall and footwall of the Dashui Fault yields identical (U-Th)/He zircon ages of ca. 210 Ma but distinct (U-Th)/He apatite ages of ca. 136 and 211 Ma, respectively. Therefore, the hanging wall and footwall are interpreted as having distinct post-mineralisation exhumation histories. Reverse fault movement exhumed the hanging wall ~2 to 4 km since the Late Triassic with the main component of faulting taking place between the Late Triassic and Early Cretaceous. These relationships suggest a Late Triassic to Early Cretaceous age for the primary gold mineralisation at the Dashui gold deposit, with the corollary that any ‘missing portion’ of the deposit, previously hypothesised to exist in the hanging wall of the Dashui Fault, has been eroded away. The mineralisation in the footwall may have been supergene enriched soon after the primary mineralisation was emplaced, because it has been located at shallow depth since the Late Triassic. Semi-quantitative results obtained in this study also constrain the maximum depth of formation of the Dashui gold at no more than 2 km.     

西藏措勤晚白垩世英安岩的厘定与地球化学特征

野外地质调查和SHRIMP锆石U/Pb地质年代学研究表明,拉萨地块中带措勤地区发育一套形成于晚白垩世中期的英安岩(88.5±1.2 Ma)。该套火山岩具有岛弧火山岩的地球化学特征,为地壳深部岩浆岩部分熔融形成的Ⅰ型岩浆岩,经历了明显的斜长石分离结晶作用。与同时代的侵入岩相比,该套火山岩为高度演化的岩浆,Rb/Sr比值较高,但Sr/Y比值较低。在拉萨地块内部,广泛发育的90～85 Ma的岩浆作用与新特提斯洋的北向俯冲作用相关。     

Borehole Stability Analysis of Horizontal Drilling in Shale Gas Reservoirs

Serious wellbore instability occurs frequently during horizontal drilling in shale gas reservoirs. The conventional forecast model of in situ stresses is not suitable for wellbore stability analysis in laminated shale gas formations because of the inhomogeneous mechanical properties of shale. In this study, a new prediction method is developed to calculate the in situ stresses in shale formations. The pore pressure near the borehole is heterogeneous along both the radial and tangential directions due to the inhomogeneity in the mechanical properties and permeability. Therefore, the stress state around the wellbore will vary with time after the formation is drained. Besides, based on the experimental results, a failure criterion is verified and applied to determine the strength of Silurian shale in the Sichuan Basin, including the long-term strength of gas shale. Based on this work, horizontal well borehole stability is analyzed by the new in situ stress prediction model. Finally, the results show that the collapse pressure will be underestimated if the conventional model is used in shale gas reservoirs improperly. The collapse pressure of a horizontal well is maximum at dip angle of 45°. The critical mud weight should be increased constantly to prevent borehole collapse if the borehole is exposed for some time.