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231.
黄嘉玲  何深静 《热带地理》2014,34(3):308-318
宗教地理是文化地理重要的研究内容之一,但在中国相关实证研究仍不多见。结合半结构问卷调查和访谈,对广州石室圣心大教堂的非洲裔移民宗教场所地方感特征及其形成机理进行探讨。研究发现:非洲裔移民宗教场所地方依恋和地方认同发展快于地方依赖;非裔移民较强的圣地地方依恋同时存在较强的空间可替代性,但又由于区位等因素存在宗教功能之外的非可替代性;圣地地方依赖则因被宗教教义视为功利性而被掩盖。回归分析表明,社交和场所互动时间是指示地方感的最显著指标。随着非粤宗教文化的融合发展,宏观政治环境以及语言文化隔离等外生因素正对宗教地方感的提高产生重要影响。  相似文献   
232.
This paper attempts to establish a method for analysing the relationship between the polar and equatorial climate of the Northern Hemisphere. The Arctic Oscillation (AO) is known to have no direct relationship with the monsoon over the Maritime Continent (MC). Thus, an index called the Siberian High(SH~Maritime Continent(MC) Index (SHMCI) is developed to represent the mean sea level pressure difference between the SH and the warm pool over the MC. This index indicates a strong link with the monsoon circulation. A positive (strong) value of the SHMCI is associated with strong meridional winds and intense and frequent cold surge events over the South China Sea. The correlation between the AO index and the SHMCI is -0.39, which is medium but statistically significant; however, it is not sufficiently conclusive to infer direct correlation. Nevertheless, the SHMCI can be used as a tool to relate the AO with the monsoon over the MC because of the influence demonstrated by the AO towards the SH. Further analysis on the convergence and divergence anomalies over the MC reveals an impact discernible only from the SHMCI. This implies that the SHMCI manifests clearly the relationship between the Arctic and equatorial climate.  相似文献   
233.
中国大陆重力场动态变化研究   总被引:20,自引:2,他引:18       下载免费PDF全文
利用国家重大科学工程"中国地壳运动观测网络"1998-2008年间绝对重力和相对重力的观测资料,初步获得了中国大陆起算基准统一的重力场及其动态变化.重力场变化既具有时空分布的不均匀性和重力变化分区现象,同时又具有与活动断裂构造密切相关和与地震孕育发展有着内在联系.中国大陆6.8级以上大震主要发生在重力场变化分布差异较为剧烈的地区(重力变化≥90×10-8m·s-2)和重力变化发生转折的时段.  相似文献   
234.
孙武国  廉涛  刘冰 《地质与资源》2016,25(2):208-212
Bambari绿岩带是一个太古宙花岗岩-绿岩带,位于刚果克拉通北部,呈北西向带状展布,长250 km,宽10~24 km.其主要组成岩性为太古宙花岗岩、条带状含铁建造(BIF)、角闪岩、绢云片岩、石英绢云片岩.在其东部的1/3地区已发现了一个大型的铁、金共生矿床,经对比研究认为,在Bambari绿岩带的中西部地区仍有重要的找矿意义.  相似文献   
235.
基于东非裂谷系西支地震地质综合解释对比研究,发现该生长型裂谷盆地受基底属性影响,主要发育陡断面地堑型盆地结构,沿边界主控断裂走向发育背离型和接近型两类主要调节构造,沿边界主控断裂倾向主要发育地垒式和地堑式两类调节构造。构造样式控制了主要成藏条件:陡断面地堑式裂谷能够形成沉积范围广、厚度大的湖相优质烃源岩;裂谷间走向调节构造属于一级调节带,控制长轴辫状河三角洲的展布;裂谷内错断的边界断裂带属于次级走向调节构造,控制中小型扇三角州的发育。倾向调节构造形成的断鼻、断块圈闭,为该类盆地的主要油气藏类型。  相似文献   
236.
The Mana district, located in the northern part of the Birimian Houndé greenstone belt in western Burkina Faso, is a world-class Paleoproterozoic orogenic gold district (∼8 Moz) including five gold deposits (Fofina, Nyafé, Siou, Wona-Kona and Yaho). These deposits are located in specific lithostratigraphic domains, and gold is controlled by various structural features. Deposit- and regional-scale mapping, intrusion age and geochemistry, as well as airborne aeromagnetic and electrical resistivity geophysical data, were used to decipher the tectonic evolution of each gold deposit and the district. Five deformational and four gold mineralizing events were recognized.The first deformation event (D1MD: E-W oriented shortening) affected the metamorphosed volcanic and sedimentary rocks of the Lower Birimian group. This early deformation episode was correlated with the formation of gently N-plunging folds (F1MD) and N-S-striking thrusts faults coeval with emplacement of the pre- to synkinematic Wona-Kona and Siou plutons dated at ∼2172 Ma, under greenschist facies metamorphism. The quartz-carbonate veins (V1MD) at Fofina and Siou formed during D1MD at Eoeburnean time, manifesting the first gold event at approximately ∼2172 Ma.The following deformation event (D2MD: E-W oriented extension) is associated with the deposition of the Upper Birimian group (Mana basin) overlying the Lower Birimian group. The geometry of the Mana basin is controlled by the Mana and Maoula shear zones. The Tarkwaian-type rock formation overlying the Upper Birimian group, controlled by the Wona-Kona and Siou shear zones, is constrained at the end of D2MD or at the beginning of the D3MD event with a maximum deposition age at ∼2113 Ma.The third deformation event (D3MD: E-W to WNW-ESE transpression) affected the entire supracrustal rock. Such event is correlated with the formation of map-scale F3MD folds and dextral shear zones during the Eburnean orogeny (∼2113–2090 Ma). A second gold mineralizing event occurred during D3MD and is manifested by quartz-carbonate veins (V3MD) and disseminated sulfides at the Yaho, Fofina and Nyafé and possibly Wona-Kona deposits.The fourth deformation event (D4MD: NNW-SSE transpression) is correlated with sinistral shearing along the major transcurrent faults and the development of asymmetric NNE-striking folds (F4MD) associated with vertical fold axes. Syn-D4MD mineralization is characterized mainly by a strong silicification (Si4MD) with disseminated pyrite and arsenopyrite along the Wona-Kona shear zone and by tiny quartz-carbonate veinlets (V4MD). This event is considered the main gold-bearing event in the western margin of the Mana district.The fifth and last deformation event (D5MD) is brittle in character and was responsible for the formation of E-W subvertical crenulation cleavages and reverse faults under overall N-S shortening. This late deformation event is tentatively associated with a last gold event recorded as free gold associated with muscovite in brittle fractures developed in competent orebodies at the Wona-Kona and Siou deposits. This event could be as young as ∼2022 Ma, the age obtained from Ar-Ar datation of muscovite-schists at the Wona-Kona deposit.Our main contribution is that we decipher multiple gold mineralizing events at the district scale based on deposit- and regional-scale mapping. It is interpreted that gold was introduced as early as ∼2172 Ma and possibly as late as ∼2022 Ma during at least 3 or even 4 shortening tectonic events in a timeframe not yet recognized at the district scale for all the Birimian belts.  相似文献   
237.
中非裂谷系前寒武系基岩油气成藏组合   总被引:1,自引:0,他引:1  
中非裂谷系是在前寒武系结晶基岩基础上发育起来的中新生代裂谷盆地群。通过露头和钻井资料研究发现,基岩主要由前寒武系岩浆岩、正变质岩和少量副变质岩组成。根据暗色矿物含量可以将基岩划分为长英质和铁镁质岩石两大类,前者更有利于风化和裂缝的形成,储层物性较好。寒武纪-侏罗纪长期风化作用形成了广泛分布且厚度较大的球形风化壳(段),早白垩世中非剪切带的走滑拉张应力场与前寒武系刚性基岩的耦合作用在基底产生了大量高角度断层、共轭缝、微裂缝和节理等,风化淋滤、表生和热液作用控制了溶蚀、胶结和次生孔隙发育。风化壳和裂缝储层发育具有“似层状”的特征,垂向上基岩潜山储层序列可进一步划分为风化淋滤带、裂缝发育带、半充填裂缝带和致密带四个区带。中非裂谷系盆地在早白垩世、晚白垩世和古近纪三期裂谷期发育了三期区域性厚层泥页岩,古近系暗色泥岩由于埋藏浅,处于未成熟阶段,不能作为有效烃源岩,上白垩统泥岩以滨浅湖相为主,有机质含量总体不高,以Ⅲ型干酪根为主,下白垩统深湖相泥岩是区域上的优质烃源岩,同时为基岩提供了良好的油源和顶盖层。根据盖层的时代,可以划分出下白垩统、上白垩统和古近系3类成藏组合。乍得Bongor盆地基岩勘探获得极大成功,发现了一批高产稀油油田,打开了中非地区一个新的油气勘探领域。  相似文献   
238.
李志刚  薛德升  杜枫  朱颖 《地理研究》2009,28(4):920-932
全球化下的中国城市社会空间面临新的重塑,以诸多大城市新近出现的跨国移民社会空间的发展最为突出。本文以广州小北黑人区为研究对象,采用三角检验法,综合利用问卷调查、深度访谈等研究手段,探讨全球化下中国城市所出现的新社会空间的地方响应。总体上,一个负面的黑人群体形象已经被建构起来。就居民的年龄、性别、教育水平、居住时间和宗教信仰等方面而言,各类本地居民在对黑人聚居的看法上并无太大差别;但不同职业类型的居民看法差别很大。排斥心理的产生多源于外在信息的影响,亦即本地媒体排斥、矮化性的负面响应。  相似文献   
239.
China is the world's biggest producer and exporter of graphite and also possesses the world's largest reserves of crystalline graphite. One of the main production areas is in northeastern China around Jixi, in Heilongjiang Province, where graphite, sillimanite and phosphate form in original sedimentary horizons within the Mashan Group. The Mashan Group is composed of khondalitic metasediments and tectonically interleaved orthogneisses, all metamorphosed to granulite facies. The peak conditions have been calculated at 800–850°C at 5.3–6.2 kb and the P–T–t path defines a tight clockwise loop involving simultaneous decrease in temperature and pressure, falling to 410–490°C at less than 3 kb. This metamorphic event is interpreted as resulting from continent–continent collision, with emplacement of mantle–derived mafic magma and possible delamination at the base of the crust. Metamorphism has been precisely dated at 500 Ma, using U–Pb zircon SHRIMP techniques. It appears likely that this terrane formed part of an originally more extensive orogenic belt of Late Pan–African age. Rocks of similar age are recorded from east Antarctica, Western Australia, India and Sri Lanka, suggesting that the Mashan Group was most likely juxtaposed with these areas within Gondwanaland. The mechanism by which the Mashan Group arrived at its present position between the Siberian and North China Cratons is poorly constrained, but it appears likely that, along with the North China, South China and Tarim Blocks, it underwent a northward drift from an initial location off northern Australia to finally dock with the Siberian Craton in the Late Permian to Late Jurassic.  相似文献   
240.
广州小北路黑人聚居区社会空间分析   总被引:37,自引:6,他引:31  
1978 年改革开放带来中国城市的快速转型。近年来, 针对经济转型背景下中国大城市 的社会空间研究很多, 但对在全球化影响下出现的跨国移民族裔聚居区的研究尚不多见。对 广州黑人聚居区展开研究, 以越秀区小北路为例, 探讨其社会空间特征与演进机制。研究采 用微观视角, 针对典型案例进行问卷调查和半结构式访谈。研究表明, 广州黑人聚居区与西 方同类族裔社会区存在诸多差异。小北路黑人聚居区因全球化下新的“自下而上”的跨国经 济联系而生, 因广州城市的商贸文化、宗教历史、贸易网络和地理气候条件而兴, 其跨国移 民多为来自西非地区的族裔散居者/ 漂泊者(Diaspora), 其人口构成异质多元, 且流动性强。 小北路的社会空间机制既包含被动隔离也包含主动聚居, 其经济形态已经开始向“族裔聚居 区经济”(ethnic enclave economy) 发展。  相似文献   
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