BOOK REVIEWS     

《The Professional geographer》1987,39(4):487-521

Book Reviewed in this article: Geographical Aspects of Health and Disease in India . Rais Akhtar and A.T.A. Learmonth , eds . Antarctic Treaty System: An Assessment . Proceedings of a Workshop at Beardmore South Field Camp, Antarctica. American Electoral Mosaics . J. Clark Archer and Fred M. Shelley . Kompas op Suidwes-Afrika/Namibie . W.S. Barnard , ed . Jerusalem in the 19th Century: The Old City . Yehoshua Ben -Arieh . The World as a Total System . Kenneth E. Boulding . A Social History of Housing 1815–1985, Second Ed . John Burnett . Human Migration . W.A.V. Clark . Regional Population Projection Models . Andrei Rogers . The State of Population Theory: Forward from Malthus . David Coleman and Roger Schofield , eds . Imagining Tomorrow: History, Technology and the American Future . Joseph C. Corn , ed. Swidden Agriculture in Indonesia: The Subsistence Strategies of the Kalimantan Kantú . Michael R. Dove . Glacial Geologic Processes . David Drewry . Physics of Desertification . Farouk El -Baz and M.H.A. Hassan , eds . Housing the Homeless . Jon Erickson and Charles Wilhelm , eds . Settlement Patterns in Missouri: A Study of Population Origins, with a Wall Map . Russel L. Gerlach . Desert Development: Man and Technology in Sparselands . Yehuda Gradus , ed . Nuclear Winter. The Evidence and Risks . Owen Greene , Ian Percival and Irene Ridge . The Take-off of Suburbia and the Crisis of the Central City . Günter Heinritz and Elisabeth Lichtenberger , eds . Regional Input-Output Analysis . Geoffrey J. D. Hewings . Spatial Transportation Modeling . Christian Werner . The Atlas of Georgia . Thomas W. Hodler and Howard A. Schretter , eds . Latin America. 5th ed . Preston E. James and C.W. Minkel . Applied Remote Sensing . C.P. Lo . Localities, Class, and Gender . The Lancaster Regionalism Group . Urban Social Movements: The City after Castells . Stuart Lowe . Politics and Method . Doreen Massey and Richard Meegan , eds . Land Use . A. S. Mather . The Kingdom of Coal . Donald L. Miller and Richard E. Sharpless . The Presidio and Militia on the Northern Frontier of New Spain, A Documentary History, Vol. 1: 1570–1700 . Thomas H. Naylor and Charles W. Polzer , S.J., comps . and eds . Nuclear Power: Siting and Safety . Stan Openshaw . The Central African Republic: The Continent's Hidden Heart . Thomas O'Toole . Environmental and Dynamic Geomorphology . Márton Pécsi , ed . Remote Sensing Principles and Interpretation . Floyd F. Sabins , Jr . Acid Rain and Friendly Neighbors: The Policy Dispute between Canada and the United States . Jurgen Schmandt and Hilliard Roderick , eds . Earth's Changing Surface: An Introduction to Geomorphology . M.J. Selby . International Migration: The Female Experience . Rita J. Simon and Caroline B. Brettell , eds . On Geography and Its History . D.R. Stoddart . Transportation Networks: A Quantitative Approach . D. Teodorovic . Processes in Physical Geography . R.D. Thompson , A.M. Mannion , C.W. Mitchell , M. Parry , J.R.G. Townshend . Imaging Radar for Resources Surveys . J.W. Trevett . Dominance and Affection: The Making of Pets . Yi -Fu Tuan . Capturing the Horizon. The Historical Geography of Transportation since the Transportation Revolution of the Sixteenth Century . James E. Vance , Jr . Nations at Risk: The Impact of the Computer Revolution . Edward Yourdon .  相似文献   

Modelling catchment‐scale erosion patterns in the East African Highlands     

Olga Vigiak  Barrack O. Okoba  Geert Sterk  Sander Groenenberg 《地球表面变化过程与地形》2005,30(2):183-196

Prompt location of areas exposed to high erosion is of the utmost importance for soil and water conservation planning. Erosion models can be useful tools to locate sources of sediment and areas of deposition within a catchment, but the reliability of model predictions of spatial patterns of erosion at catchment scale has seldom been validated against observations. This study aimed to evaluate the performance of a simple empirical model (Morgan, Morgan and Finney model, MMF) in predicting spatial patterns of erosion at two small catchments in the East African Highlands: Kwalei (Tanzania) and Gikuuri (Kenya). Erosion maps predicted by the MMF model were compared with erosion maps obtained by direct survey. In Kwalei, erosion features were especially frequent in fields of annual crops. In Gikuuri, slope was the critical erosion factor, with estimated erosion rates >10 kg m^?2 a^?1 on slopes >18 per cent. Predicted erosion rates were mainly transport‐limited and ranged from <0·01 to 13·50 kg m^?2 a^?1 in Kwalei and 9·29 kg m^?2 a^?1 in Gikuuri. The performance of the MMF model in predicting the spatial patterns of erosion was acceptable in Kwalei, but poor in Gikuuri. However, by excluding the elements at the valley bottoms in Gikuuri Catchment, the performance of the model improved dramatically. The spatial pattern of erosion predicted by the MMF model was driven by the accumulation of surface runoff, which did not consider the possibility of re‐infiltration along the slope. As a result, the MMF erosion patterns predicted by the model increased invariably from the ridges to the valley bottoms, hampering the model suitability for locating areas subjected to high and very high erosion. It is concluded that the model predictions could be substantially improved by introducing a more realistic hydrological component for the prediction of surface runoff along the hill‐slope. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

意大利上新世古生产力的轨道驱动     

丁晓辉  王汝建  李建如  黄恩清 《地球科学进展》2007,22(10):1019-1026

主要研究了意大利上新统3个剖面Punta Piccola、Cape Spertivento以及Punta Rossello蛋白石含量的变化，综合其它古环境指标对非洲季风和地中海表层生产力加以分析，研究表明，Punta Piccola剖面和Cape Spertivento剖面各古环境指标对岁差周期影响的响应明显而单纯，即岁差低值，对应氧同位素偏负，有机碳和蛋白石高值以及碳酸盐低值，说明地中海表层生产力明显受到岁差的驱动。岁差驱动下的北非夏季风导致尼罗河泛滥，带来的丰富营养元素使得生产力剧增，同时淡水注入，阻碍了水体的垂向交换，直接导致了海底的缺氧环境，硅藻利用深层营养产生勃发，并组成“藻席”，快速沉降到海底，使得有机碳迅速埋葬和保存，从而引发了腐泥层的形成。Punta Rossello剖面硅藻层证实了“藻席”的存在，但是蛋白石含量并不高。 [HT5H]关 键 词:[HT5K] [HT5H]中图分类号： 文献标识码：A[HT5SS][HK]  相似文献   

Petrology and CHIME geochronology of Pan-African high K and Sr/Y granitoids in the Nkambe area, Cameroon   总被引：1，自引：1，他引：0  

Samuel Tetsopgang  Kazuhiro Suzuki  Emmanuel Njonfang 《Gondwana Research》2008,14(4):686

The Central African Belt in the Nkambe area, northwestern Cameroon represents a collisional zone between the Saharan metacraton and the Congo craton during the Pan-African orogeny, and exposes a variety of granitoids including foliated and massive biotite monzogranites in syn- and post-kinematic settings. Foliated and massive biotite monzogranites have almost identical high-K calc-alkaline compositions, with 73–67 wt.% SiO₂, 17–13 wt.% Al₂O₃, 2.1–0.9 wt.% CaO, 4.4–2.7 wt.% Na₂O and 6.3–4.4 wt.% K₂O. High concentrations of Rb (264–96 ppm), Sr (976–117 ppm), Ba (3680–490 ppm) and Zr (494–99 ppm), with low concentrations of Y (mostly< 20 ppm with a range 54–6) and Nb (up to 24 ppm) suggest that the monzogranites intruded in collisional and post-collisional settings. The Sr/Y ratio ranges from 25 to 89. K, Rb and Ba resided in a single major phase such as K-feldspar in the source. Garnet was present in the source and remained as restite at the site of magma generation. This high K₂O and Sr/Y granitic magma was generated by partial melting of a granitic protolith under high-pressure and H₂O undersaturated conditions where garnet coexists with K-feldspar, albitic plagioclase. CHIME (chemical Th–U-total Pb isochron method) dating of zircon yields ages of 569 ± 12–558 ± 24 Ma for the foliated biotite monzogranite and 533 ± 12–524 ± 28 Ma for the massive biotite monzogranite indicating that the collision forming the Central African Belt continued in to Ediacaran (ca 560 Ma).  相似文献   

Genesis of marine terrace soils,Barbados, West Indies: Evidence from mineralogy and geochemistry     

Daniel R. Muhs  Russell C. Crittenden  John N. Rosholt  Charles A. Bush  Kathleen C. Stewart 《地球表面变化过程与地形》1987,12(6):605-618

Well-developed, clay-rich soils dominated by interstratified kaolinite-smectite are found on the uplifted coral reef terraces on the island of Barbados. The reef limestone is unlikely to have been the soil parent material however, because it is 98 per cent CaCO₃ and geomorphic evidence argues against the 20 m of reef solution required to produce the soils by this process. The mineralogy of the sand, silt, and clay fractions of the soils, and trace element geochemistry, suggest that aeolian materials carried on the trade winds from Africa, volcanic ash from the island of St. Vincent, and quartz from Tertiary bedrock on the island itself are the parent materials for the soils.  相似文献   

东非大裂谷的地壳和上地幔密度结构     

钱知之  杨文采 《地质论评》2024,70(1):1-8

利用卫星重力场数据和小波多尺度分析方法对东非大裂谷进行三维密度结构成像,取得了东非大裂谷地壳和上地幔多个深度等效层上的密度扰动图像,为东非大裂谷岩石圈结构和动力学的研究提供了重要佐证。结果表明,东非大裂谷中段的西支裂谷与东支裂谷的幔源熔体同源,但是西支裂谷发育较不充分、形成较晚。东非大裂谷的动力学模式为熔流体上涌的树形分叉模式,其要点包括：① 低密度流体在软流圈大面积上涌;② 流体在岩石圈继续上涌,部分转化为基性岩浆岩,平面面积缩小;③ 进入地壳后上涌熔流体分叉成多支,平面总面积进一步缩小; ④ 熔流体上涌到上地壳后仅在裂谷带活动,反映为火山链和玄武岩带。  相似文献   

The petroleum geochemistry of the Termit Basin,Eastern Niger     

《Marine and Petroleum Geology》2014

Sixty crude oils from the Termit Basin (Eastern Niger) were analysed using biomarker distributions and bulk stable carbon isotopic compositions. Comprehensive oil-to-oil correlation indicates that there are two distinct families in the Termit Basin. The majority of the oils are geochemically similar and characterized by low Pr/Ph (pristane to phytane ratios) and high gammacerane/C₃₀ hopane ratios, small amounts of C₂₄ tetracyclic terpanes but abundant C₂₃ tricyclic terpane, and lower δ¹³C values for saturated and aromatic hydrocarbon fractions. All of these geochemical characteristics indicate possible marine sources with saline and reducing depositional environments. In contrast, oils from well DD-1 have different geochemical features. They are characterized by relatively higher Pr/Ph and lower gammacerane/C₃₀ hopane ratios, higher amounts of C₂₄ tetracyclic terpane but a low content of C₂₃ tricyclic terpane, and relatively higher δ¹³C values for saturated and aromatic hydrocarbon fractions. These geochemical signatures indicate possible lacustrine sources deposited under freshwater, suboxic-oxic conditions. This oil family also has a unique biomarker signature in that there are large amounts of C₃₀ 4α-methylsteranes indicating a freshwater lacustrine depositional environment.The maturity of the Termit oils is assessed using a number of maturity indicators based on biomarkers, alkyl naphthalenes, alkyl phenanthrenes and alkyl dibenzothiophenes. All parameters indicate that all of the oils are generated by source rocks within the main phase of the oil generation stage with equivalent vitrinite reflectance of 0.58%–0.87%.  相似文献   

Diurnal cycle of precipitation over the Maritime Continent simulated by a spectral cumulus parameterization     

《Dynamics of Atmospheres and Oceans》2020

The validity of a spectral cumulus parameterization (spectral scheme) for simulating a diurnal cycle of precipitation over the Maritime Continent (MC) was examined using a regional atmospheric model. The impacts of entrainment parameterization and each type of convective closure, i.e., non-equilibrium (or equilibrium) closure for deep convection, mid-level, and shallow convective closures, were also examined. When vertically variable entrainment and appropriate convective closures were employed, the model adequately simulated a diurnal cycle of precipitation over both land and ocean as compared to the observation. Analysis regarding the entrainment parameterization revealed that variable entrainment parameterization was needed not only for simulating better mean patterns of precipitation, but also for more realistic phases of diurnal cycles. The impacts of convective closures appeared in the differences in the precipitation amplitude. Analysis on diurnal cycles of convective properties and tendencies revealed that the cycles between boundary layer forcing and convective heating determined convection strength and were affected by each type of convective closure. It can be concluded that the spectral scheme with appropriate convective closures is able to simulate a realistic diurnal cycle over the MC.  相似文献   

东非裂谷系西支中南段Karoo地层分布特点与勘探前景     

许志刚 《吉林地质》2014,(1):14-19

东非裂谷系一直是世界油气勘探重点关注区,尤其在西支Albertine盆地获得重大油气发现,而与之具有相似成因演化的西支中南段其它盆地,勘探潜力一直不明朗并急待挖掘。中-古生代Karoo地层及分布在该地区广泛分布,特别是作为烃源和主要的勘探层系在东非海岸陆缘盆地被广泛证实后,Karoo的勘探潜力备受关注。然而,Karoo本身经过漫长的演变,涵盖的地质学内容包罗万象,混淆不清,十分不利于该地区油气勘探潜力的研究和判断。本文通过系统查阅国外文献并结合东非裂谷系的研究工作,初步查明Karoo的成因、演变及分布,并系统评价Karoo地层在西支中南段裂谷盆地及周边的分布,探讨其勘探意义。但以Karoo作为东非地区未来勘探领域仍然面临着一系列不确定性的问题和风险,值得思索和总结。  相似文献   

中非造山带：喀麦隆北部地质构造与河流沉积物重矿物分析     

叶浩  Merlain Houketchang Bouyo  赵越  刘健 《地质力学学报》2014,20(2):103-113

简要叙述冈瓦纳超大陆聚合过程和中非造山带泛非期地质构造过程,剖析了西冈瓦纳喀麦隆北部和乍得西南地区岩石构造单元及其形成的构造背景并对喀麦隆北部河流冲积物进行了重矿物分析。分析结果表明重矿物可能来自近源基岩,为西喀麦隆地体(Western Cameroon Domain)内的雷博巴(Rey Bouba)绿岩带和马约科比(Mayo Kebbi)弧岩浆岩带;重矿物中的自然金可能主要来自雷博巴绿岩带。分析结果为该地区砂金矿开采提供了一定的指示。  相似文献