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桂东大桂山地区震旦系培地组硅质岩地球化学特征及沉积环境探讨 被引量:1
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作者 荣红 吴年冬 王忠伟 《四川地质学报》 2023年第2期339-346,共8页
桂东大桂山地区震旦系中上部的硅质岩沉积建造,具层状、块状构造。其中Al_(2)O_(3)含量较高,与TiO_(2)含量呈正相关关系;REE总量较低,δEu值为1.02~1.40,δCe值为0.94~1.42;大部分微量元素相对地壳克拉克值亏损,但Ba、As、Sb、Bi等少数... 桂东大桂山地区震旦系中上部的硅质岩沉积建造,具层状、块状构造。其中Al_(2)O_(3)含量较高,与TiO_(2)含量呈正相关关系;REE总量较低,δEu值为1.02~1.40,δCe值为0.94~1.42;大部分微量元素相对地壳克拉克值亏损,但Ba、As、Sb、Bi等少数几种元素相对富集,在Fe-Mn-(Ni+Co+Cu)×10三角图中投影均落在热水沉积区,这些特征均反映硅质岩为热水沉积为主并混染有正常沉积作用的产物。在Al-Fe-Mn三元图中的投影均落在热水沉积区域;再结合Al/(Al+Fe+Mn)值和Si/(Si+Al+Fe)值,同样反映硅质岩以热水成因硅质岩为主,但在沉积过程中可能混入了正常沉积的陆缘粘土物质。δCe值、(La/Ce)_(shale)值、(La/Yb)_(sbale)值、Al_(2)O_(3)/(Al_(2)O_(3)+Fe_(2)O_(3))值,Fe_(2)O_(3)/TiO_(2)-Al_(2)O_(3)/(Al_(2)O_(3)+Fe_(2)O_(3))图解和(La/Ce)_(shale)-Al_(2)O_(3)/(Al_(2)O_(3)+Fe_(2)O_(3))图解均反映硅质岩沉积环境为大陆边缘。 展开更多
关键词 培地组 硅质岩 地球化学 沉积环境 桂东
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桂东寒武系培地组硅质岩成因与金的富集 被引量:7
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作者 蔡明海 刘国庆 《华南地质与矿产》 CAS 2000年第1期29-33,共5页
根据岩石特征、化学成分、微量元素及稀土配分特征认为 :本区硅质岩是在大陆边缘坳陷环境下喷流热水沉积作用的产物 ;金在硅质岩及与之相伴的含碳泥页岩沉积过程中初步富集 ,而在后期热液改造成矿过程中再次聚集。指出硅质岩可作为桂东... 根据岩石特征、化学成分、微量元素及稀土配分特征认为 :本区硅质岩是在大陆边缘坳陷环境下喷流热水沉积作用的产物 ;金在硅质岩及与之相伴的含碳泥页岩沉积过程中初步富集 ,而在后期热液改造成矿过程中再次聚集。指出硅质岩可作为桂东地区培地组中寻找沉积 展开更多
关键词 硅质岩 喷流热水沉积 寒武系 培地组 沉积-改造型金矿床 成矿作用
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论桂东南地区培地组的归属
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作者 董宝林 雷英凭 《广西地质》 1997年第4期21-24,共4页
文章从盆地控制沉积的观点出发,提出桂东南的培地组应该与桂北的老堡组、湘南的留茶坡组等含硅质地层对比,归属于震旦系。这样华南盆地加里东旋回(包括晚震旦世)中的地层序列就可以从层序地层和海平面变化等方面得到统一的解释。文... 文章从盆地控制沉积的观点出发,提出桂东南的培地组应该与桂北的老堡组、湘南的留茶坡组等含硅质地层对比,归属于震旦系。这样华南盆地加里东旋回(包括晚震旦世)中的地层序列就可以从层序地层和海平面变化等方面得到统一的解释。文中还介绍了同位素年龄和化石方面的新资料。 展开更多
关键词 广西 震旦系 培地组 地层对比 地层
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Effects of Land Management Practices on Labile Organic Carbon Fractions in Rice Cultivation 被引量:8
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作者 SHAO Jing'an LI Yangbing +1 位作者 WEI Chaofu XIE Deti 《Chinese Geographical Science》 SCIE CSCD 2009年第3期241-248,共8页
A research trial with four land management practices, i.e., traditional tillage-fallow (TTF), traditional tillage-wheat (TTW), conservation tillage-fallow (CTF) and conservation tillage-wheat (CTW), was sampled in the... A research trial with four land management practices, i.e., traditional tillage-fallow (TTF), traditional tillage-wheat (TTW), conservation tillage-fallow (CTF) and conservation tillage-wheat (CTW), was sampled in the 15th year after its establishment to assess the effects of different management practices on labile organic carbon fractions (LOCFs), such as easily oxidizable organic carbon (EOC), dissolved organic carbon (DOC), particulate organic carbon (POC) and microbial biomass carbon (MBC) in a typical paddy soil, Chongqing, Southwest China. The results indicated that LOCFs were significantly influenced by the combination of no-tillage, ridge culture and crop rotation. And, different combination patterns showed different effectiveness on soil LOCFs. The effects of no-tillage, ridge culture and wheat cultivation on EOC, DOC, POC and MBC mainly happened at 0-10cm. At this depth, soil under CTW had higher EOC, DOC, POC and MBC contents, compared to TTF, TTW and CTF, respectively. Moreover, the contents of LOCFs for different practices generally decreased when the soil depth increased. Our findings suggest that the paddy soil in Southwest China could be managed to concentrate greater quantities of EOC, DOC, POC and MBC. 展开更多
关键词 NO-TILLAGE rice-wheat rotation ridge culture labile organic carbon fraction rice cultivation
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Comparative effects of plant growth regulators on leaf and stem explants of Labisia pumila var. alata 被引量:2
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作者 Anna Pick Kiong LING Kinn Poay TAN Sobri HUSSEIN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第7期621-631,共11页
Objective: Labisia pumila var. alata, commonly known as 'Kacip Fatimah' or 'Selusuh Fatimah' in Southeast Asia, is traditionally used by members of the Malay community because of its post-partum medici... Objective: Labisia pumila var. alata, commonly known as 'Kacip Fatimah' or 'Selusuh Fatimah' in Southeast Asia, is traditionally used by members of the Malay community because of its post-partum medicinal properties. Its various pharmaceutical applications cause an excessive harvesting and lead to serious shortage in natural habitat. Thus, this in vitro propagation study investigated the effects of different plant growth regulators (PGRs) on in vitro leaf and stem explants of L. pumila. Methods: The capabilities of callus, shoot, and root formation were evaluated by culturing both explants on Murashige and Skoog (MS) medium supplemented with various PGRs at the concentrations of 0, 1, 3, 5, and 7 mg/L. Results: Medium supplemented with 3 mg/L indole-3-butyric acid (IBA) showed the optimal callogenesis from both leaf and stem explants with (72.34±19.55)% and (70.40±14.14)% efficacy, respectively. IBA was also found to be the most efficient PGR for root induction. A total of (50.00±7.07)% and (77.78±16.47)% of root formation were obtained from the in vitro stem and leaf explants after being cultured for (26.5±5.0) and (30.0±8.5) d in the medium supplemented with 1 and 3 mg/L of IBA, respectively. Shoot formation was only observed in stem explant, with the maximum percentage of formation ((100.00±0.00)%) that was obtained in 1 mg/L zeatin after (11.0±2.8) d of culture. Conclusions: Callus, roots, and shoots can be induced from in vitro leaf and stem explants of L. pumila through the manipulation of types and concentrations of PGRs. 展开更多
关键词 AUXIN CYTOKININ Labisia pumila In vitro propagation Plant growth regulators
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