西澳大利亚金色丛林铜矿床的硫同位素和矿石成因的初步研究

由块状黄铜矿—磁铁矿透镜体组成的太古代层状金色丛林(Golden Grove)矿床的δ~(34)S_(CDT)值范围从-1.4per mil到 4.4 permil(平均 1.0 permid。类似的分布也来自矿化层(范围-2.5到 4.0,平均 0.9)和富Zn的上盘燧石层(范围-0.1到4.3,平均 1.6)浸染状的硫化物中。由于沉淀和成岩的影响,在共生的硫化物系统中同位素具不平衡性,通过绿片岩相变质作用而保存下来。对于地层最高的铜透镜体平均δ~(34)S值中两个per mil的减损说明当硫化物沉积时,在矿液中向高fo_2的临时变化。这些资料证实了海底硫化物的堆积模式是在活动构造环境中发生间隙性喷发作用的结果。说明岩浆(少年期)硫是矿液中硫的主要来源。     

陆相红层的古地磁演化

陆相红层的古地磁学,是以赤铁矿不同结构相的成岩起源的资料为依据进行研究的。文中讨论了作为磁化载体的含颜料的赤铁矿和镜铁矿的相对作用,并且得出了所有磁化都是后生沉积获得的结论:即陆相红层的磁化是由成岩起源的。在陆相红层中,判明有A、B、C三种非粘滞磁化类型。A型磁化保留着原生磁化的一些特征,并与岩石的沉积年代最吻合。B型是复含磁化类型,是经过很长时间(大约10~6年)获得的,并在周围地磁场中经历了实质性的改变。C型磁化与岩石的成岩作用的年代无关,它相当于陆相红层成岩过程的最终产物。因此,这些磁化类型反映了红层成岩作用的不同发展阶段。成岩发展的速率,也就是磁化强度的改变速率是变化的,并且,它取决由各种局部地质作用的变化。     

地磁活动指数

一、行星性指数K和A 行星性指数表示地磁活动的一般状态,该指数是从位于中纬度地区(这是为了减少电急流的影响)经过挑选的一些地磁台计算出来的,并作为其余几十个地磁台的标准。但是,和所有的指数一样,由于地磁台的分布不够适当和外源场高度不规则,使行星性指数也蒙受其损害。例如,在某些情况下,极区亚暴对于所挑选的地磁台的磁照图是没有影响的,而在另一些情况下,也许由于极区电急流的赤道迁移,使得极区亚暴对磁照图也有很大的影响。实际上,行星性指数表示了许多外源场的扰动变化的混合效应,该指数对于地磁现象的相关研究是很有用的。     

地震磁异常和电阻率变化的主要事记

世界一些多地震国家如日、美、苏、中等国报道了许多地震磁电前兆的观测震例、理论分析与实验模拟、以及预报实践的结果,它们在地震预报研究及地球电磁现象探测中起到交流借鉴的作用。根据1965—1981年所发表的研究论文材料,按年代顺序以大事记和附表(还列入地电异常)形式,将地磁异常和电阻率变化这两方面的震磁电现象综合汇编介绍如下,以供参考。     

Whole-bird models for the magnetic cleansing of oiled feathers

Iron powder, a promising dry-cleansing agent for oiled feathers where both the contaminant and the cleansing agent may be harvested magnetically, has been tested on the plumage of whole-bird models. The breast and back plumage of Mallard Duck (Anas platyrhynchos) and Little Penguin (Eudyptula minor) carcasses were patch-contaminated with commercial-grade engine oil, three different crude oils, and an oil/seawater emulsion. The plumage was then subjected to a magnetic cleansing protocol. The contaminant removal was assessed gravimetrically and was found to reflect the outcomes for a previously reported in vitro study using feather clusters. Between 92-98% of the contaminants, and effectively all of the cleansing agent, were removed from the feathers.     

Dissolved and particulate fluxes of copper through the Morlaix river estuary (Brittany, France): mass balance in a small estuary with strong agricultural catchment

Dissolved and particulate copper were measured over an annual cycle (12 surveys between February 1998 and January 1999) in the Morlaix Estuary (Brittany, France). These variations were investigated in both the water column and the benthic compartment in order to calculate fluxes of copper within estuary. In the water column, dissolved and particulate copper concentrations ranged from 0.6 to 19.0 nM and from 0.03 to 2.3 micromol g(-1), respectively. In the benthic compartment, copper concentrations in superficial sediment varied from 0.04 to 0.32 micromol g(-1) and from 7.6 to 80.5 nM in the pore waters. The results show that copper contents in the water column reached levels commonly observed in estuaries affected by heavy industrial activities. Agricultural activities, extensively developed on the drainage basin, may be responsible for the copper excess. Mass balance of copper indicates that the metal accumulated within the estuary with a rate ranging from 97 to 119 kg yr(-1).     

Distributions of inorganic nutrients in the bohai sea of china

1　Introduction　TheBohaiSeaislocatedinthenorthernChinawithlongitudesofbetween 117°38′Eand 12 2°31′Eandlat itudesofbetween 37°0 8′Nand 4 1°0 2′N .Itisashal lowseawithanaveragewaterdepthof 18m (LiuandZhang ,2 0 0 0 ) .Severalbigrivers ,suchastheLiaoheRiver,theHaiheRiverandtheYellowRiver ,findtheirwaysintotheBohaiSeaandtransportlargeamountofnutrientsandsuspendedmattersfromthecontinentintothesea (Zhangetal.,1994 ;Zhang ,1996 ) .Duringthelasttwodecades ,marineenviron mentintheBohai…     

Nonlinear fitting method of long-term distributions for statistical analysis of extreme negative surge elevations

1　Introduction　Thestormsurgeduetoamovingmeteorologicalde pressioncausesabnormalchangesofseasurfaceeleva tion ,includingthenegativesurgeelevations .Hydro logicfrequencyanalysisofnegativesurgeelevationsplaysanimportantroleinmarinestructuredesignanddisasterprevention .Thedeterminationofthedesignparameterswillgreatlyaffecttheplanningofnaviga tion .Variousstudieshavecontributedvaluablefind ingstothistopic (e.g.CarterandChallenor ,1981;IsaacsonandMacKenzie ,1981;Muir ,1986 ;Goda ,1988;Vledder …     

Studies on the effects of polyaspartate protease fertilizer enhancer in the absorptions of soil nutrition and the enzymatic activities of crops

1　Introduction　Chinaisboththelargestproducerandthelargestconsumerofchemicalfertilizersintheworld .Since1984 ,Chineseconsumptionofchemicalfertilizerhasincreasedmorethanonetimes ,fromabout 17millionmetrictonsto 35millionmetrictons .However ,dur ingthesameperiod ,theyieldoffoodproductionhasincreasedonlyabout 10 % .Thediscrepancybetweenfertilizerconsumptionandyieldincreasehasindicatedthedrasticdecreaseofthebenefitsofchemicalfertiliz ers .Infact ,theutilizationefficiencyofnitrogenfer tilizerinC…