Chemical Composition and REE Pattern of Hydrothermally Deposited Albitite in Northern Guangdong Province
-
摘要: 大沟谷含金钠长石岩带上为层状下为脉状产于震旦系乐昌峡群片岩中,主要由钠长石岩及碳酸盐岩组成。钠长石岩多为块状及条带状构造。钠长石岩和片岩化学成分不同,钠长石岩相对富集Al2 O3 、TiO2 、MnO、Na2O、P2O5,而贫Fe2O3 、FeO、MgO、CaO、K2 O。在主要氧化物组成的直角坐标图上,钠长石岩和片岩位于不同的区域及具不同的变化趋势。钠长石岩稀土元素含量较低,在 12.5 6× 10 -6～ 5 5.6 6× 10 -6之间,具较低的La/Yb(1.82～ 6.42 )、La/Sm(0.96～ 2.99)、Gd/Yb(0.99～ 2.71)比值,较大的δEu异常范围 (0.41～ 0.8),弱的δCe异常。钠长石岩地质产状特征及稀土元素特征表明其主要是热水沉积形成的。Abstract: Dagougu gola-bearing albitite belt,composed of albitite and carbonate rock,occurred as stratiform in the upper part and filled veins in the lower part in the Lechangxia Group Schist,Sinian Period．The albitite usually with banded and massive structure is composed primary of albite(80％±),quartz(1％～15％±),carbonate rock(1％--5％±),rutile(1％±),apatite(1％±)and pyrite with minor tourmnaline and magnetite；the carbonate rock。occurred in the same occurrence as those of albitite,consists predominantly of dolomite(ankerite)(> 75％),calcite(>15％),albite(5％±)with the same minor minerals as those of albitite． Main element compositions of the albitite differ from that of the Lechangxia Group Schist,the former is rich in A12O3。TiO2,Mno,Na2O。P2O5 and poor in Fe2O3,Feo,Mgo,Cao,K2O．The albitite and adjacent I．Lechangxia Group Schist lie in different domains in the major oxides variation diagram including TiO2-A12O3, AL2O3一SiO2,Mgo-Sio,TiO2-SiO2,Feo-Fe2O3,Mgo-Cao and reveal different variation tendency． The albitite has lower REE content,raring from l2．56×10-6to 55．66*10-6with lower La/Yb：1．82～6．42,La/Sm：0．96～2．99,Gd/Yb：O．99-2．71 ratios,negative Eu anomalies and weakly Ce anomalies．Chondrite-normalized patterns of REE in albitite differ from those of the Lechangxia Group Schist． Ccmbined field and geochemical data indicate that the Dagougu gold-bearing stratiform albitite do not represent the normal clastic sedimeents altered by sodium rich fluid．but owe its origin to hydrothermal sedimentation at or below the sediment-wlater interface in alkaline environment．
-
Key words:
- albitite /
- REE /
- hydrothermal sedimentation Northern /
- Guangdong
-
[1] 1.Rona P A H-ydrothermal mineralization deposits in ocean crust 1978(02)
2.陈先沛;高计元;陈多福热水沉积作用的概念和几个岩石学标志 1992(03)
3.祁思敬;李英;曾章仁秦岭热水沉符号型铅锌(铜)矿床 1993
4.祁思敬;李英秦岭泥盆系铅锌成矿带 1993
5.韩发;R W哈钦林大厂锡多金属矿床热液喷气沉积的证据-含矿建造及热液沉积岩[期刊论文]-矿床地质 1989(02)
6.韩发;孙海田Sedex型矿床成矿系统[期刊论文]-地学前缘 1999(01)
7.Lijima A;HeinJR Siliceous deposits in Pacific region,Develop-ments in sedimentology 36 1983
8.Herzing P M Hydrothermal silica chimner field in Galapayos spreeding center at 86w 1988(01)
9.AdachiM;Yamamoto K;Suigisk R Hydrothermal chert and associat-ed siliceous rocks from the Northem Pacific:their geological significance as indication of ocean ridge a ctiving 1986(1-2)
10.周永章丹池盆地热水沉成因硅质岩地球化学特征 1990(03)
11.Bostroem K Genesis of ferromanganese deposits-diagnostic criteria from recent and old deposits1983
12.Fle Hydrothermal and hydrogeneous ferromanganes deposits 1983
13.Slack J F;Herriman N;Bames R Stratiform toumalinites in metamorphic teranes and their geological significance 1984(12)
14.Plimer IR Tourmalinites associated with Australia proterozoic subma-rine exhalative ores 1988
15.Taylor B E;Slack J F Tourraline from Appalachian-Caledonian mas-sive sulfide deposits: textural,chemical and isotopic relationships 1984
16.Willner A P Torumalinites from the stratiform peraluminous mmta-morphic suit of the Central Namaqua Mobile Belt (South Africa) 1992
17.张奋生;彭少梅;伍广宇粤北新州地区乐昌峡群的层序和特征 1991(03)
18.彭少梅粤北大沟谷碎裂钠长石岩型金矿床的构造-热液成矿机理 1993
19.Slack J F Origin and significance of Tourmaline-rich rocks in the Bro-ken HiAll destrict,Australia 1993(03)
20.Qi Lia ng;HuJing;Gregoire D C Determination of trace elements ingranites by inductively coupledplasma mass spectrometry[外文期刊] 2000
21.朱大岗粤北大沟谷式金矿床地质特征及成因探讨 1994(03)
22.王中刚;于学元;赵振华稀土元素地球化学 1989
23.季克俭热液矿床的矿源水源及热源以及矿床分布规律 1992
24.Klinkhammer G Rare earth elements in seawater near hy-drothermal vents 1983
25.Marchard A Rareearthelementsanduraniuminhigh-tempera-ture solutions from East pacific Rise hydrothermal vent field (13N) 1983
26.Eugster H P;Jones B F Gels composed of sodium-aluminum silicate,Lake Magadi, Kenya 1968
27.Coveney R M;Kelly W C Dawsonite as a daughter mineral in hy-drothermal fluid inclusions 1971(04) -
点击查看大图
计量
- 文章访问数: 686
- HTML全文浏览量: 11
- PDF下载量: 328
- 被引次数: 0
下载:
