岩溶含水层系统参数空间分布的优化研究—以焦西矿区为例

本文在研究焦西矿区岩溶含水层系统的基础上,提出了一种新的岩溶含水层系统参数识别模型(简称NOPRI模型)该模型利用不规则有限网格差分形式计算各时段各节点均衡子域剩余水量,并以其平方和作为目标函数,在对焦西矿区水文地质条件进行研究的基础上,建立约束方程,利用可变误差多面体法求解参数(导水系数,矿坑涌水量分配系数);并与实际水文地质条件和《焦作地区岩溶水开采资源评价及开发利用研究》所得的参数进行分析对比。NOPRI模型是一种直接求参法。      

Intrusion-Related Gold Deposits of North China Craton, People's Republic of China

Abstract. Intrusion‐related gold deposits are widely distributed within the North China craton or along its marginal fold belts. Presently, about 200 individual intrusion‐related gold deposits (prospects) have been discovered, among which Yuerya, Anjia‐yingzi, Linglong, Jiaojia, Chenjiazhangzi, Qiyugou, Jinjiazhuang, Dongping, Hougou, Huangtuliang, Guilaizhuang, Wulashan and Donghuofang are the most important ones. In general, the intrusion‐related gold deposits can be classified into three major groups according to their host rocks: (1) hosted by or related to felsic intrusions, including (la) calc‐alkaline granitoid intrusions and (lb) cryptoexplosion breccia pipes; (2) related to ultramafic intrusions, and (3) hosted by or related to alkaline intrusions. The first group contains the Yuerya, Anjiayingzi, Linglong, Jiaojia, Chenjiazhangzi and Qiyugou gold deposits. Gold mineralization at these deposits occurs within Mesozoic Yanshanian calc‐alkaline granitoid intrusions or cryptoexplosion breccia pipes as gold‐bearing quartz veins and replacement bodies. Pyrite, galena, sphalerite, chalcopyrite, native gold and electrum are major metallic minerals. The Jinjiazhuang deposit belongs to the second group, and occurs within Hercynian diopsidite and peridotite as quartz veins and replacement bodies. Pyrite, marcasite, arsenopyrite, native gold and electrum are identified. The third group includes the Dongping, Hougou, Huangtuliang, Guilaizhuang, Wulashan and Donghuofang deposits. Gold mineralization at these deposits occurs predominantly within the Hercynian alkaline intrusive complexes as K‐feldspar‐quartz veins and replacement bodies. Major metal minerals are pyrite, galena, chalcopyrite, tellurides, native gold and electrum. All these pyrite separates from Hercynian and Yanshanian intrusions or cryptoexplosion pipes associated with the gold deposits show a broad range in δ³⁴S value, which is overall higher than those Precambrian rocks and their hosted gold deposits. For the alkaline intrusion‐related gold deposits, the δ³⁴S values of the sulfides (pyrite, galena and chalcopyrite) from the deposits increase systematically from orebodies to the alkaline intrusions. All of these intrusion‐related gold deposits show relatively radiogenic lead isotopic compositions compared to mantle or lower crust curves. Most lead isotope data of sulfides from the gold ores plot in between the fields of the intrusions and Precambrian metamorphic rocks. Data are interpreted as indicative of a mixing of sulfur and lead from magma with those from Precambrian metamorphic rocks. Isotopic age data, geological and geochemical evidences suggest that the ore‐forming materials for the intrusion‐related gold deposits were generated during the emplacement of the Hercynian or Yanshanian intrusion. The calc‐alkaline or alkaline magma may provide heat, volatiles and metals for the intrusion‐related gold deposits. Evolved meteoric water, which circulated the wall rocks, was also progressively involved in the magmatic hydrothermal system, and may have dominated the ore fluids during late stage of ore‐forming processes. Therefore, the ore fluid may have resulted from the mixing of calc‐alkaline or alkaline magmatic fluids and evolved meteoric water. All these intrusion‐related gold deposits are believed to be products of Hercynian or Yanshanian calc‐alkaline and alkaline igneous processes along deep‐seated fault zones within the North China craton or along its marginal belts.     

Scandium geochemistry of phosphorites, Guizhou, Southwest China

Geochemical characteristics of scandium are described with respect to its source,evolution and correlation with REE as observed in Late Sinian and Early Cambrian phosphorites and tuffs in Guizhou.Gomparison of chondrite-nomalized REE patterns and some other parameters between the phosphorite and tuff shows that scandium and REE are most likely to have been derived from earlier or contemporaneous marine volcanics or tuffs,with no indication of genetic link to the purple shales,silstones and dolomites in the area.The conditions under which the Sc-bearin phosphorites were formed are discussed in the light of sulfur isotopes and Eh-Ph constrains.     

武汉东湖是如何形成的?

东湖位于湖北省武汉市中心城区,是中国乃至亚洲最大的城中湖之一.她是首批国家重点风景名胜区和国家5A级旅游景区.武汉市正在打造东湖城市生态绿心.东湖对于武汉在资源、环境、生态、人文各方面均具有重要意义.关于东湖的成因长期众说纷纭.研究首次从地质、地貌、沉积等方面对东湖的成因进行了分析,并对东湖与长江的关系进行了讨论.（1）东湖位于中-晚更新世形成的岗地区.湖汊发育,岸线蜿蜒,岬湾交错,是东湖最大的特点.（2）东湖的湖相沉积厚度各处不一,总体呈现南薄北厚、边缘薄中间厚的特点.下伏主要地层为晚更新世下蜀黄土,在靠近基岩残丘的南部边缘局部为晚更新世坡积层,两者之间为明显的侵蚀接触关系.（3）东湖的湖盆形成于距今2万年左右的末次冰期盛期.东海海平面的大幅度下降,长江河床深切.发育于长江南岸珞珈山、南望山、喻家山一带的地表径流,在汇入长江时因江水水位较低而发生侵蚀,形成多条冲沟组合而成的侵蚀洼地.之后,随着冰后期的全球变暖,长江水位快速上升,两岸天然堤发育、壮大,使侵蚀洼地的出口被淤塞,逐渐积水成湖,即东湖为沟谷壅塞湖.（4）根据湖泊地质地貌特征,东湖与沙湖是两个不同成因且相对独立的湖泊;长江并未经东湖流过.但东湖的形成与长江有关,乃是全球气候变化驱动下海、江、湖相互作用的产物.（5）东湖之美,美于自然.保护其自然特质,顺应其自然规律,是东湖保护与利用必须坚持的原则.将湖域、湖岸、岸上作为一个整体,将水域和流域作为一个系统,按照山水林田湖草生命共同体的科学理念,对东湖进行整体性和系统性的保护与治理是十分必要的.      

我国云南江城氯氧镁铝石的研究

氯氧镁铝石(Koenenite)是一种少见矿物,最初发现于德国Gttingen。后来,F.里勒(F.Rinne)、R.库恩(R.Kühn)、H.-H.洛斯(H.-H.Lohse)、R.奥勒曼)R.Allmann)等人先后都作过报导,而在我国还是首次发现。氯氧镁铝石结构比较特殊,性质上是一个多变的矿物。     

Hydrogeology of the Ordos Basin,China

The Ordos Basin is located in the east of NW China that is composed of different aquifer systems. Karst groundwater is stored in the Carmbrian-Ordovician carbonates along the margins of the basin. Fissured-pore water is present in the Cretaceous strata in the central-western basin and pore water is stored in the overlying Quaternary deposits discontinuously. The main origin of groundwater in the basin is direct or indirect infiltration of precipitation. Groundwater flows from recharge areas to adjacent local discharge areas. Besides evaporation and abstraction, groundwater feeds springs and rivers, such as the Yellow River and its tributaries. According to the karst aquifer lithologic structure, the features of karst development and circulation, the karst aquifer is divided into three structural and circulation patterns. Based on the control of Cretaceous sedimentary environment, lithologic structure, lithofacies, and palaeogeographic characteristics, the Cretaceous system is divided into the northern desert simple plateau aquifer system and the southern loess plateau aquifer system. PACKER was used to obtain temperature, hydrogeochemical and isotope data at specific depths. Groundwater circulation is studied using hydrodynamic fields, temperature fields, isotopes, hydrogeochemical data and numerical simulations. According to the result, it is divided into local, intermediate and regional systems.     

三江源地区美丽中国建设存在的问题、成功案例与启示

长江、黄河与澜沧江源区（简称三江源区）是中华与亚洲“水塔”,是我国重要的生态安全屏障与水安全保障,是三大河流域经济带的共有源地,稳藏固疆的战略要地,美丽中国建设的战略高地。掌握该地区美丽中国建设进程,发现存在的问题,及时总结典型成功案例,有助于更好建设美丽高原,服务生态文明建设与社会经济高质量发展的全国战略部署。就建设内容与进程看,目前三江源区整体仍处于物质建设阶段,除畜牧业外,缺乏其他产业,忽视文化建设,美丽缺少内涵、不可持续;就建设成效而言,美丽乡村与美丽城镇工程建设成绩显著,但配套设施严重滞后,以及游牧文化与聚落文化的冲突,美丽仍流于形式;尽管存在这些问题,但亦涌现了若干成功案例,“岗龙模式”和“甘达模式”尤为典型,为三江源其他地区美丽中国建设提供了样板与发展启示：（1）找准优势资源,最大化资源潜力、实现经济“美”是高原美丽中国建设成功的物质基础;（2）领导人/团队/致富带头人是高原美丽中国建设成功的关键核心;（3）产业与因地制宜的运作机制是高原美丽中国建设可持续的强大支撑与必由之路;（4）不断探索永远走在发展路上是美丽中国建设成功的坚实动力。     

阿克塞红柳沟纤蛇纹石矿物学特征研究

在对阿克塞红柳沟温石棉矿床的地质特征分析的基础上,采用XRF、XRD、FT-IR、SEM、TG-DTA等分析测试方法对4个纤蛇纹石样品进行了化学成分、晶体结构、谱学特征、显微形貌与理化性质研究。结果表明:纤蛇纹石样品的主要化学组成为SiO2、MgO,其次含有Al2O3、Fe2O3及少量的NiO等类质同象组分,为典型的斜纤蛇纹石结构,内外羟基伸缩振动和Si-O伸缩振动吸收峰尖锐、分裂明显,纤维形态表现为柔韧的丝状,结构破坏温度在650~700℃,酸蚀量在43.67%~59.89%之间,碱蚀量在2.72%~7.01%之间。矿床地质特征和纤蛇纹石的矿物学特征表明该矿床形成后遭受后期的地球化学作用破坏程度低,与纤蛇纹石共生的矿物较简单,纤蛇纹石纤维表面结构较完善。     

云南墨江志留纪地层及其笔石序列

云南墨江志留纪地层从下到上包括漫波组和水箐组。根据在水箐组中发现的大量笔石,从下到上共识别出Colonograptuspraedeubeli带、C.ludensis带、Lobograptusprogenitor带、L.scanicus带和Saetograptusfritschilinearis带等5个笔石带,并将各带与捷克、中亚、加拿大和我国广西等地的相应笔石带进行了详细对比。研究表明水箐组的时代应属文洛克世晚期—罗德洛世中期,其层位应在文洛克世早期的漫波组之上。     

Chemical Zone of Nephrite in Alamas,Xinjiang, China

The Hetian deposit, located south of the Tarim Basin in Xinjiang, China, is one of the world's largest dolomite-related nephrite deposits. In the Alamas orebody of the deposit, nephrite occurs as veins or lenses along faults or fissures of the adjacent dolomitic marble. Chemical analyses using electronic microscope probe analysis and X-ray fluorescence spectroscope were carried out on nephrite and dolomitic marble samples collected from a cross section in Alamas to investigate zonal structure of the orebody. The nephrite in Alamas is predominately composed of tremolite with minor calcite, titanite and phlogopite, and that dolomitic marble is relatively pure with a FeO content less than 0.20 wt. %. Contents of color-inducing elements, such as Fe, Mn, and Cr, increase gradually as color changes from white through white-green and then to green, resulting in the formation of color-distinctive zones. Tremolite grain size increases as color changes from white through white-green to green. The trend may be consistent with temperature changes from dolomitic marble to granodiorite, which, in turn, suggests that both change in color from white to green and variations of grain size with increasing temperature resulting in formation of the nephrite zonal structure. Both nephrite zonal structure and minor minerals, such as calcite, titanite and phlogopite found in the contact, indicate that this dolomite-related nephrite orebody is of a metasomatic origin under assumed pressure of 100–200 MPa and temperature <550°C.     

福建云霄石榴子石宝石矿物学特征

福建云霄是我国重要的宝石级石榴子石产地,然而该区石榴子石的致色机理不清,制约了对其形成机制的理解及后续开发利用。本文选取7件福建云霄橙黄-橙红色石榴子石样品,利用傅立叶红外光谱、紫外-可见光光谱和拉曼光谱分析其谱学特征,使用电子探针及激光剥蚀电感耦合等离子体质谱仪(LA-ICP-MS)分析限定其主量、微量元素组成。结果表明云霄石榴子石主要为锰铝榴石,其颜色主要与二价锰(Mn²⁺)和铁离子(Fe²⁺)对可见光的吸收有关,Mn²⁺导致其主体呈橙色,少量Fe²⁺控制其橙红色调,微量Ti⁴⁺使其呈褐色调。福建云霄石榴子石样品核部锰含量相对较低而铁、镁含量较高,锰元素含量由核部向边部逐渐升高,且具有重稀土元素富集、轻稀土元素亏损的左倾配分模式和Eu负异常,表明其形成于岩浆结晶作用晚期。     

东秦岭商丹断裂带南侧武关岩群的锆石LA-ICP-MS U-Pb年龄

用LA-ICPMS定年技术测得武关岩群变玄武岩中继承性成因锆石的平均206Pb/238U年龄为348Ma+18/-12Ma。这一年龄代表了继承性锆石受炽热玄武岩浆改造而重结晶的年龄。综合分析认为,武关岩群的时代可能为晚泥盆世。     

新疆东准噶尔锡矿北花岗斑岩的锆石LA-ICP-MS U-Pb测年

对东准噶尔锡矿北花岗斑岩进行锆石LA-ICP-MS U-Pb测年,获得206Pb/238U加权平均年龄为(281±10)Ma,MSWD=9.3,206Pb/238U-207Pb/235U谐和曲线图中下交点年龄为(278±11)Ma,MSWD=7.5,两者在误差范围内完全一致,时代属于早二叠世。结果表明,锡矿北花岗斑岩形成的时代属于东准噶尔后碰撞深成岩浆活动的范围(330～265Ma),晚于东准噶尔乌伦古河碱性花岗岩和卡拉麦里碱性花岗岩的形成时代（300Ma左右）,以花岗斑岩为代表的晚古生代岩浆侵入活动延续到早二叠世晚期。     

Land subsidence in Tianjin,China

Land subsidence has been affecting Tianjin for the past 50 years. It leads to comprehensive detrimental effects on society, the economy and natural environment. Overpumping of groundwater is the main cause. In 2008, the maximum cumulative subsidence reached 3.22 m and the total affected area nearly 8,000 km². The subsidence reached its most critical state in the early 1980s when it occurred at a rate as high as 110 mm/year. At the same time, groundwater extraction had also reached a maximum of 1,200 million m³. By importing the Luan River to Tianjin and restricting exploitation of groundwater, hydraulic heads gradually recovered after 1986 in all aquifers, and this has continued to the present in the second aquifer. The subsidence rate in urban areas dropped to 10–15 mm/year. The area of groundwater extraction expanded to the suburban area with economic growth in the 1990s, and it was shifted to the third and fourth aquifers. At present, with a subsidence rate of 30–40 mm/year, four new suburban subsidence centers have been formed. Several measures were adopted to mitigate and prevent land subsidence disasters. These included restricting groundwater exploitation, groundwater injection, prohibiting use in the specific zone, a pricing policy for water resources, advocating water-saving technology, and strict enforcement of groundwater laws. Although the subsidence area is still increasing slowly, the subsidence rate is being controlled.     

Tourmalinite from northern Guangxi,China

The extensive development of tourmalinite is a feature that distinguishes the northern Guangxi polymetallic tin province of China from similar metallogenic provinces elsewhere. Two types of tourmalinite occur in the province. The first type, in the lower part of the Early Proterozoic Sibao Group, is bedded, stratiform or lenticular tourmalinite that shows well-developed laminated, gel, and degelatinized structures. Its mineral assemblage is very simple and the grain size ranges from 2 to 8 m. This tourmaline is relatively rich in Mg, with an Fe/(Fe + Mg) ratio of 0.25–0.50.The second type of tourmalinite occurs as lodes distributed in the exocontact zone of Late Proterozoic biotite-granite intrusions. Its mineral assemblage is relatively complex; the tourmaline is present as euhedral or subhedral crystals ranging from 0.1 to 3.5 mm, mostly from 0.5 to 1 mm. This tourmaline commonly exhibits a radiating, zoned structure with Fe/(Fe + Mg) ratios of 0.64–0.79. It is suggested that the bedded tourmalinite formed by exhalation in an Early Proterozoic spreading-ridge environment, whereas the vein tourmalinite formed in a plate-convergence setting genetically associated with emplacement of Late Proterozoic biotite granite. As the tourmalinites themselves are related to mineralized rocks and orebodies, their origin and the related boron cycle of the region reflect to some extent the formation and evolution of the associated polymetallic tin deposits of the region.     

北京地区长城系

北京地区长城系是位于高于庄组之下、老变质基底岩系之上的一套地层。1)区内发育两层稳定的凝灰岩———翠绿色层和棕红色层 ,可作为地层对比的标志层 ;2 )长城系底部的砂岩、页岩具穿时性 ,大红峪组存在明显的相变关系 ,不能只根据岩性进行分组。据此 ,把北京地区原长城系高于庄组之下地层重新厘定为大红峪组一段 ,包括原常州沟组、串岭沟组、团山子组和大红峪组一段 ;大红峪组二段即原大红峪组二段和大红峪组三段即原大红峪组三段 ,并与蓟县剖面进行了对比。