内蒙古达茂旗东北部比旗格淖复式岩体的形成年龄、地球化学特征及成因

达茂旗东北部比旗格淖复式岩体位于内蒙古中部,该岩体由两期侵入体组成,岩性分别为花岗闪长岩和二长花岗岩,前者为岩体主体岩性。主体花岗闪长岩主要由斜长石（An=14 ~ 30）、石英、钾长石和普通角闪石组成,内部发育暗色微粒包体;补体二长花岗岩主要由石英、钾长石和斜长石（An=12 ~ 23）组成。LA- ICPMS锆石U- Pb定年显示岩体形成于晚二叠世,形成年龄为259±2 Ma。主体花岗闪长岩SiO2=66. 37%-68. 70%、为准铝质—弱过铝质（A/CNK=0. 99 ~ 1. 01）,地球化学上显示出富集轻稀土、大离子亲石元素,亏损重稀土和高场强元素的特征,属于I型花岗岩;其中闪长质暗色微粒包体呈浑圆状或拉长扁平透镜状,年龄与寄主花岗闪长岩一致,为岩浆混合的产物;补体二长花岗岩,高硅（SiO2=71. 51% ~ 73. 09%）、富碱（Na2O+K2O=7. 91% ~ 8. 61%）,为弱过铝质—强过铝质（A/CNK=1. 07 ~ 1. 11）,属分异I型花岗岩。比旗格淖复式岩体锆石εHf(t)分布范围为-3. 0 ~ 3. 4,对应的Hf同位素二阶段模式年龄为1473 ~ 1057 Ma。具有相对较低的\[n(87Sr)/n(86Sr)\]i值（0. 704829 ~ 0. 705327）,εNd(t)值为-5. 85 ~ -8. 86,对应的Nd的二阶段模式年龄为1. 69 ~ 1. 45 Ga。结合区域研究资料,认为比旗格淖复式岩体为亏损地幔组分与受其诱发的部分熔融的古老地壳物质混合形成,属于后碰撞型花岗岩,这类岩体的形成标志了古亚洲洋在兴蒙造山带南缘的闭合,并发生造山后伸展作用。     

华南桂东南地区加里东期Ⅰ型花岗岩类的岩石成因及构造意义

龙新岩体和夏郢岩体位于扬子地块与华夏地块拼合带的西南端,岩体中的Ⅰ型花岗岩成因研究对揭示桂东南地区早古生代的地球动力学背景及其构造演化具有重要的地质意义.对龙新岩体的寄主岩和其暗色微粒包体,以及夏郢岩体岩石进行了LA-ICP-MS锆石U-Pb定年、Lu-Hf同位素和全岩地球化学研究.锆石U-Pb定年结果显示,龙新岩体的寄主岩（花岗闪长岩）的年龄为440±2 Ma;龙新岩体的暗色包体（闪长岩）的年龄为441±1 Ma,寄主岩与暗色包体为同期岩浆作用的产物.夏郢岩体花岗闪长岩和二长花岗岩年龄分别为447±3 Ma和436±3 Ma,说明夏郢岩体至少发生了2期岩浆侵入事件.Hf同位素研究表明,龙新岩体寄主岩和暗色微粒包体的锆石ε_Hf（t）值分别为-3.32~-5.83和-17.89~-1.82,二阶段模式年龄（T_DM2）分别为1.62~1.76 Ga和1.57~2.54 Ga;夏郢岩体早期花岗岩闪长岩和晚期二长花岗岩的锆石ε_Hf（t）值分别为-15.43~3.03和-4.79~6.82,T_DM2分别为1.59~1.99 Ga和0.97~1.70 Ga,指示物源主要来自古-中元古代的地壳物质.地球化学特征表明龙新岩体寄主岩为准铝质高钾钙碱性Ⅰ型花岗岩,寄主岩和暗色微粒包体均富集轻稀土元素和大离子亲石元素,亏损重稀土元素及高场强元素;夏郢岩体早期的花岗闪长岩为弱过铝质高钾钙碱性Ⅰ型花岗岩,晚期的二长花岗岩则为强过铝质高钾钙碱性Ⅰ型花岗岩,主微量元素特征均与龙新岩体寄主岩相似.根据研究区花岗岩和镁铁质包体的岩相学、年代学、地球化学及Hf同位素组成特征,表明龙新岩体的暗色包体（闪长岩）为岩浆混合成因,而龙新岩体寄主岩（花岗闪长岩）和夏郢岩体（早期花岗岩闪长岩和晚期二长花岗岩）具有一致的岩石源区和岩石成因,但在后期的成岩过程中存在岩浆混合和结晶分异程度的差异.综合以往对华南地区构造背景的研究,认为龙新和夏郢岩体是在扬子地块和华夏地块陆内造山期后,岩石圈伸展减薄,热的幔源岩浆上涌底侵,中-下地壳受到地幔热影响发生部分熔融,形成的酸性岩浆在源区和基性岩浆经历了不均一且不强烈的壳-幔混合作用形成的.      

藏东洛隆地区早白垩世冻错岩体岩石成因及构造意义

北拉萨地体广泛发育白垩纪岩浆岩,但是对其岩石成因及其动力学背景仍存在争议。本次研究选取西藏洛隆地区冻错岩体为研究对象,在野外地质调查基础上进行了岩石学、岩石地球化学、锆石U-Pb年代学和Hf同位素研究。结果表明：冻错岩体主要为花岗闪长岩和二长花岗岩,且发育暗色闪长质包体;锆石U-Pb测年结果显示花岗闪长岩(127.6±1.0 Ma, 129.9±0.9 Ma)和二长花岗岩(131.7±1.1 Ma)的形成时代为早白垩世;花岗闪长岩具有负的ε_Hf(t)值(-12.9～-10.3)和古老的二阶段模式年龄(1 809～1 977 Ma);岩体花岗岩类的SiO₂,Al₂O₃和全碱(Na₂O+K₂O)质量分数分别为67.01%～72.35%,14.37%～16.55%和6.49%～8.11%,里特曼指数(σ)为1.52～2.30,铝饱和指数A/CNK值为0.90～1.12,属准铝质-弱过铝质I型花岗岩类。闪长质包体SiO₂,Al₂     

青海泽多桌肉地区花岗闪长岩与暗色包体地球化学特征及成因

青海泽多桌肉地区花岗闪长岩中发育大量暗色闪长质包体。通过对花岗闪长岩(寄主岩石)与暗色包体的地球化学研究发现,花岗闪长岩(寄主岩石)的SiO_2含量为w(SiO_2)=61.61%~68.80%,A/CNK=0.91~0.99,属于偏铝质钙碱性花岗岩特征;暗色包体中发育针状磷灰石,暗色包体的SiO_2含量为w(SiO_2)=52.66%~66.99%,碱度率AR=2.08~2.26(大于1),里特曼指数σ=1.89~8.67,固结指数SI=16~24.74,属过铝质钙碱性花岗岩。稀土元素分析显示,花岗闪长岩稀土总量w(ΣREE)=117.44×10~(-6)~265.68×10~(-6);暗色包体稀土总量w(ΣREE)=184.05×10~(-6)~342.11×10~(-6),总量高于寄主岩石;暗色包体和寄主花岗岩有着相似的稀土元素配分模式,显示轻稀土富集,重稀土亏损,轻重稀土元素分馏明显的特征。微量元素分析显示,暗色包体微量元素的分布型式与寄主岩微量元素特征基本一致,大离子亲石元素K、Rb、Ba相对富集,高场强元素Nb、Ta、Zr、Hf相对亏损,反映了岩浆混合作用的特征。在花岗闪长岩中获得LA-ICP-MS锆石U-Pb年龄为202.49 Ma±0.63 Ma,属晚三叠世。表明泽多桌肉花岗闪长岩属于晚三叠世以来的造山带伸展崩塌造成岩石圈较快速减薄以及幔源岩浆底侵作用的发生,并导致地壳岩石接近熔融温度产生壳源岩浆而成岩。     

北秦岭板山坪岩体锆石U-Pb年代学及岩石成因研究

板山坪岩体是北秦岭二郎坪群中的侵入岩。为了查明该岩体的成因,对该岩体进行了锆石U-Pb年代学、锆石原位Hf同位素研究以及矿物化学分析等方面的研究。研究结果表明,板山坪岩体岩性组成主要为石英闪长岩和花岗闪长岩,花岗闪长岩内部存在暗色包体。本次研究获得板山坪石英闪长岩锆石U-Pb年龄为442.7～432.2 Ma,花岗闪长岩锆石U-Pb年龄为436.8～432.7 Ma,暗色包体锆石U-Pb年龄为437.6 Ma。锆石¹⁷⁶Hf/¹⁷⁷Hf值为0.282 737～0.282 736,ε_Hf（t）值集中分布在8.4～9.4之间,二阶段Hf模式年龄（T_DM2）在876～832 Ma之间。石英闪长岩结晶温压分别为673 ℃～745 ℃和0.19～0.54 GPa,花岗闪长岩结晶温压分别为657 ℃～730 ℃和0.48～0.96 GPa,暗色包体结晶温压分别为680 ℃～734 ℃和0.69～1.65 GPa。综合分析认为板山坪岩体为复式岩体,两期结晶年龄分别为496～487 Ma和442～432 Ma。岩石来源于地幔分离出来的新生下地壳。     

西藏冈底斯带西部达雄岩体的岩石成因:锆石U-Pb年龄和Hf同位素约束

对出露于冈底斯西部地区措勤北部达瓦错东侧的达雄岩体进行了锆石U-Pb定年、全岩主量元素、微量元素、Sr-Nd同位素和锆石Hf同位素研究,以约束其岩石成因。达雄岩体的主体岩性为花岗闪长岩,其中发育大量闪长质包体。花岗闪长岩的锆石LA-ICP MS年龄为107±1Ma,该年龄代表了岩体结晶年龄。花岗闪长岩锆石ε_(Hf)(t)值变化于-1.0～3.0,两阶段模式年龄变化于974～1226Ma。花岗闪长岩富硅(SiO_2=70.65%～71.10%),富钙(CaO=3.21%-3.26%)、贫钾(K_2O= 2.81%～2.99%)、低P_2O_5(0.09%),铝饱和指数(A/CNK)为1.01～1.02,属于偏铝质花岗岩或弱过铝质花岗岩。闪长质包体Sio_2含量为57.84%,与寄主岩相比,闪长质包体更富CaO、MgO、TFe_2O_3和TiO_2。花岗闪长岩和闪长质包体均属中钾钙碱性系列,ε_(Nd)(t)值分别为-4.6和-3.2,两阶段模式年龄(t_(DM2))相近(分别为1277Ma和1166Ma),并与锆石Hf同位素模式年龄一致。岩相学、年代学和地球化学研究表明闪长质包体可能是由岩浆混合作用形成的镁铁质微粒包体。我们的初步研究成果似乎表明,冈底斯中西部地区在早白垩世晚期(～110Na)很可能存在一次重要的岩浆混合作用,这一初步认识对研究冈底斯中北部地区规模宏大的白垩纪岩浆作用的深部动力学过程具有重要意义。     

皖南旌德花岗闪长岩与暗色包体的成因: 地球化学、锆石U-Pb年代学与Hf同位素制约

旌德复式岩体位于安徽南部,主体相花岗闪长岩中发育暗色包体。本文对花岗闪长岩与暗色包体进行了岩相学观察、全岩主微量元素分析、锆石U-Pb定年与Hf同位素测试。岩相学观察发现暗色包体为典型岩浆岩结构,且发育针状磷灰石。主量元素分析数据表明花岗闪长岩的SiO₂含量为66.04%~67.80%;暗色包体的SiO₂含量为54.63%~54.77%,为二长闪长岩。花岗闪长岩的Mg^#=38~40;暗色包体的Mg^#=44~45。微量元素分析数据表明花岗闪长岩与暗色包体的REE球粒陨石标准化图呈右倾型,Eu负异常;大离子亲石元素富集,高场强元素亏损。锆石U-Pb年代学与Hf同位素研究表明,花岗闪长岩与暗色包体的年龄分别为139.7±1.3Ma和142.3±1.7Ma,在误差范围内一致。花岗闪长岩锆石的ε_Hf(t)为-2.5~0.4,地壳模式年龄(t_DM^C)为1170~1350Ma;暗色包体锆石的ε_Hf(t)为-5.2~1.8,地壳模式年龄(t_DM^C)为1090~1530Ma。两者的t_DM^C峰值都在1.2~1.3Ga。这些数据表明花岗闪长岩中的暗色包体为同源岩浆混合成因,源区为年轻地壳,有可能为中新元古代古华南洋壳俯冲扬子板块形成的火山岛弧。旌德花岗闪长岩在Pearce et al.(1984)的构造判别图上落在岛弧花岗岩区。在Sr/Y-Y图解上落在经典岛弧岩浆岩区。花岗闪长岩的岩浆Zr饱和温度低(630~680℃),与锆石钛温度计(630~720℃)给出的结果基本一致。锆石的Ce(Ⅳ)/Ce(Ⅲ)高(240~530),指示岩浆具有高的氧逸度。旌德岩体的低温与高氧逸度特征说明岩体的源区物质受到过洋壳俯冲的影响。旌德岩体的成因可能与太平洋板块后撤诱发的地壳部分熔融有关。     

冈底斯印支期造山事件: 花岗岩类锆石U-Pb年代学和岩石成因证据

对冈底斯中部地区二云母花岗岩和花岗闪长岩进行了LA-ICP-MS锆石U-Pb定年、主量元素、微量元素和锆石Hf同位素组成的测定.结果表明, 二云母花岗岩的岩浆结晶年龄为(205± 1)Ma, 岩石属于强过铝质花岗岩, A/CNK= 1.16~ 1.20, K₂O/Na₂O= 1.67~ 1.95.岩石富Rb、Th和U等元素, Eu/Eu* = 0.29~ 0.41, (La/Yb)_N= 22.62~ 35.08.锆石ε_Hf(t)= -12.4~ -1.8.二云母花岗岩的岩浆产生于地壳中泥质岩类在无外来流体加入的情况下云母类矿物脱水反应所诱发的部分熔融作用, 其岩石形成机制类似于喜马拉雅新生代淡色花岗岩.花岗闪长岩的岩浆结晶年龄为(202± 1)Ma, 岩石属于准铝质(A/CNK= 0.96~ 0.98), K₂O/Na₂O= 1.42~ 1.77, Eu/Eu* = 0.54~ 0.65, (La/Yb)_N= 6.76~ 13.35.锆石ε_Hf(t)= -8.2~ -5.5.根据花岗闪长岩的地球化学特征和锆石Hf同位素组成, 花岗闪长岩的岩浆来自于地壳中基性岩类的部分熔融.冈底斯印支晚期强过铝质花岗岩的确定, 表明了冈底斯在印支晚期以前曾发生地壳的缩短与加厚作用, 从而进一步明确了冈底斯印支早期的造山事件及冈底斯经历了多期造山作用的演化.      

赣南早古生代晚期花岗岩类年代学、地球化学及岩石成因

本文研究了赣南会同岩体花岗岩类及其闪长质包体的岩石学、锆石U-Pb定年和Hf同位素以及全岩主量、微量元素地球化学。会同岩体花岗岩年龄为425.8±6.2Ma,花岗闪长岩包体为425.0±4.1Ma,侵入年龄约为425Ma,属于早古生代晚期的志留纪。岩体总体为过铝质到强过铝质(A/CNK=1.05~1.28)、高钾钙碱性系列岩石;花岗岩和包体的微量元素和稀土元素特征一致,均富集Rb、Th、U、K、Pb,亏损Ba、Sr、P、Ti,Eu负异常明显。岩石属于S型花岗岩。花岗岩和包体ε_Hf(t)均为负值,变化范围大(分别为-13.7~-3.3,-8.4~-3.2),Hf同位素地壳模式年龄较老(总体为1.6~2.3Ga)。结合前人资料,认为早古生代晚期赣南地区,在后碰撞伸展背景下,发生了大范围的成熟地壳的强烈再造和深熔作用,源于中、下地壳的熔体在约425Ma侵位形成中酸性岩浆,再向上侵位形成会同岩体。     

冀东分水岭岩体锆石U-Pb年代学、地球化学特征及地质意义

冀东分水岭岩体位于马兰峪隆起西段,为复式岩体,其岩性为花岗闪长岩和黑云母二长花岗岩,花岗闪长岩呈带状环绕黑云母二长花岗岩分布,锆石U-Pb定年揭示其年龄分别为157.4±2.7Ma和162.0±4.0Ma。花岗闪长岩的SiO_264.50%~65.56%,K_2O+Na_2O 7.24%~7.70%,K_2O/Na_2O 0.58~0.67,A/CNK0.91~0.97,呈高硅富钾,属准铝质高钾钙碱性系列,为I型花岗岩;而黑云母二长花岗岩SiO_273.25%~74.56%,K_2O+Na_2O 7.22%~8.58%,K_2O/Na_2O 0.86~1.04,A/CNK 1.09~1.24,较花岗闪长岩更富硅、钾,为过铝质高钾钙碱性系列,属成熟度不高的A型花岗岩。两者稀土配分曲线呈右倾型式,具稀土总量较低,轻重稀土分馏明显,微量元素均亏损Nb-Ta、Zr-Hf,显示以壳源成分为主,具幔源混染特征。花岗闪长岩具弱Eu正异常,且富集Sr,源区深度较大;而黑云母二长花岗岩具Eu负异常,亏损Sr,源区有少量斜长石残留。岩体形成与太平洋板块俯冲构造背景密切相关,为中生代构造转换体制的产物。     

Wavelength-dispersive X-ray fluorescence spectrometric determination of Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites

Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.     

高压微波消解法测定醋酸纤维过滤器采集的微尘粒子中的砷镉钴铬铜铁锰镍铅钒锌

最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提     

Isotopic systematics of He,Ar, S,Cu, Ni,Re, Os,Pb, U,Sm, Nd,Rb, Sr,Lu, and Hf in the rocks and ores of the Norilsk deposits

This paper reports the first results of a study of 11 isotope systems (³He/⁴He, ⁴⁰Ar/³⁶Ar, ³⁴S/³²S, ⁶⁵Cu/⁶³Cu, ⁶²Ni/⁶⁰Ni, ⁸⁷Sr/⁸⁶Sr, ¹⁴³Nd/¹⁴⁴Nd, ^206–208Pb/²⁰⁴Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.     

硅酸盐中铁、锰、钛、钙、钾、磷、硅、铝、镁、钠、锶、铷、钡的X-射线荧光光谱定量测定

本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。     

硅酸盐类样品中硅、铁、铝、钛、锰、钙、镁、钾、钠和磷的x射线荧光光谱测定

本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。     

Viscous, cohesive, non-Newtonian, depositing, radial slurry flow

Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.     

Regional distribution of Al,B, Ba,Ca, K,La, Mg,Mn, Na,P, Rb,Si, Sr,Th, U and Y in terrestrial moss within a 188,000 km2 area of the central Barents region: influence of geology,seaspray and human activity

Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km² area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).     

NEW SET OF LOW CONCENTRATION STANDARDS FOR LA, CE, SM, YB, LU, Y, SC, V, NB AND TA IN SILICATES

We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al₂O₃-SiO₂ ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses.     

Mountains,nations, parks,and conservation

Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km² and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.