An Unnatural Metropolis: Wresting New Orleans from Nature by Craig E. Colten     

Matthew Liesch 《The Professional geographer》2006,58(4):499-500

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“GREAT OPPORTUNITIES FOR THE MANY OF SMALL MEANS”: NEW JERSEY'S AGRICULTURAL COLONIES*     

DEBORAH E. POPPER 《Geographical review》2006,96(1):24-49

ABSTRACT. Pogroms in the Russian Pale in 1881 set off a wave of immigration of Russian Jews to the United States. Most went to the cities, but an important group, with the support of philanthropic organizations, became part of an experiment in Jewish agricultural colonies. South Jersey's Alliance and Woodbine were the most successful. Both were established on undeveloped land, and the landscape that emerged suggests the importance the funders placed on using landscape as a means of Americanization.  相似文献   

Evolution of Cretaceous–Cenozoic quartz pebble conglomerate gold placers during basin formation and inversion, southern New Zealand     

J.H. Youngson  D. Craw  D.M. Falconer 《Ore Geology Reviews》2006,28(4):451

Numerous auriferous fluvial quartz pebble conglomerates (QPCs) are present within the Late Cretaceous–Recent sedimentary sequence in southern New Zealand. The QPCs formed in low-relief settings before, during, and after regional marine transgression, in alluvial fan and a variety of fluvial and near-shore depositional settings: In particular, during slow thermal subsidence associated with Late Cretaceous–early Cenozoic rifting, and during the early stages of orogenic uplift following mid Cenozoic marine regression. QPC maturity characteristics are complex and vary with sediment transport and recycling history, stratigraphic proximity to the transgressive Waipounamu Erosion Surface, and the amount of first-cycle detritus incorporated during recycling. For pre-marine QPCs, the amount of first cycle detritus varies with tectonic intensity and proximity of the depositional setting to remnant Cretaceous topography. For post-marine QPCs, it varies with tectonic intensity and proximity to Late Cenozoic uplift of basement ranges.QPCs do not form during a single bedrock erosion–sediment deposition cycle: Non-oxidised and/or oxidized groundwater alteration (kaolinisation) of labile minerals in immature sediment and the upper part of underlying basement, and repeated sedimentary recycling, are fundamental processes of QPC formation regardless of the tectonic or sedimentary settings. Altered immature rock disaggregates easily upon erosion, and alteration clays are winnowed to leave quartz-rich residues containing resistant heavy minerals such as zircon and gold. Detrital sulfide survives recycling if deposition and burial in saturated sediments are rapid. QPCs result only if sediment recycling is not accompanied by excessive erosion of fresh basement rock. Uplift of many parts of the Otago Schist belt since late Miocene has raised rocks above the water table, increased erosion rates, and inhibited groundwater alteration and QPC formation. QPC formation is still occurring in Southland, where the water table is high, sediments are saturated and undergoing alteration, and uplift and erosion rates, topography, and fluvial gradients are all low. The QPCs accumulate as residual gravel on the valley floors of low-competence streams that are slowly incising pervasively altered dominantly late Miocene–Pliocene immature conglomerates.QPCs formation essentially represents physical and chemical lagging of precursor strata. Accumulation of detrital gold and other heavy minerals is an inevitable consequence, and most QPCs contain some gold. Three types of significant gold placer have developed in the QPCs. Type 1 placers are essentially eluvial and/or colluvial in origin and form without significant fluvial transport, by residual accumulation in low-competence valleys during low-rate uplift, fluvial incision and QPC formation. Type 2 placers have formed during significant fluvial transport and subsequent fluvial incision, mainly in higher energy proximal and medial reaches of larger pre-marine (Eocene) and post-marine fluvial systems. Type 3 placers formed by wave-base and marine current winnowing in the shallow shelf setting during low-rate regional marine transgression, especially in the Eocene.  相似文献   

A proscoliine wasp (Insecta: Hymenoptera: Scoliidae) from Shandong peninsula, East Asia     

Junfeng Zhang   《Cretaceous Research》2006,27(6):788-791

A new species of wasp from the Laiyang Formation in Shandong, China is described and named Cretaproscolia asiatica sp. nov. It is the second record of the genus Cretaproscolia Rasnitsyn and Martínez-Delclòs, 1999, and extends the distribution of the genus from the Lower Cretaceous of South America into the upper Mesozoic of East Asia. The diagnosis of Cretaproscolia is emended based on the new material.  相似文献   

大姚铜矿小河-石门坎矿段隐伏矿找矿新思路     

刘皓  刘星  薛传东  张皙  骆少勇 《云南地质》2006,25(1):25-30

以区内隐伏矿带连续存在为基础，根据野外实地调查和对已有图件资料的综合分析，重点研究构造控矿规律，提出本区隐伏矿应以9^#勘探线附近为转向对称轴的新思路。  相似文献   

江苏句容磨盘山地区茅西断裂的新认识     

李端璐  赵为民 《江苏地质》2006,30(1):21-23

句容磨盘山高速公路隧道工程地质勘探中,发现龙王山组逆覆在浦口组之上,又被Q1-2砾石层不整合覆盖。据该现象所处的空间位置可以认为,该断裂即为茅西断裂,其活动时间应在K2p浦口组沉积之后,且有一组(至少两条)断裂组成。  相似文献   

Making New Zealanders through commemoration: Assembling Anzac Day in Auckland, 1916–1939     

Matthew Henry 《New Zealand geographer》2006,62(1):3-12

Abstract:  Anzac Day in New Zealand has been traditionally framed within a nationalist discourse, in which the events of the day have provided the medium for the remembrance of a singular national event. Moving beyond this interpretative tradition the paper examines Anzac Day as a moment in the exercise of an ongoing governmental power concerned with issues of contemporary conduct. Focusing on interwar Auckland the paper traces the assemblage of time, space and rhetoric, which enabled the production of a commemorative, governmental landscape.  相似文献   

苏州西郊覆盖区物探找矿回顾     

黄启声 《江苏地质》2006,30(1):13-16

苏州市西郊是江苏省找矿前景较好的地区。20世纪60年代磁法普查找矿阶段,发现小茅山银铜矿、淡家桥铜硫铁锌矿、旺米山铁锌矿、陈家沟铁矿及南爪山铁矿;20世纪70年代资料二次开发找矿阶段,发现光福铁铅锌矿、迂里北段矿、吴宅中型铅锌银矿、燕头张铁矿及唐家墩铁矿;20世纪80年代新技术新方法应用找矿阶段,发现迂里南段矿,使迂里成为中型的铅锌银矿床。  相似文献   

Velocity and anisotropy structure at the Hikurangi subduction margin, New Zealand from receiver functions   总被引：1，自引：0，他引：1  

Martha K. Savage  J. Park  H. Todd 《Geophysical Journal International》2007,168(3):1034-1050

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Ambient noise Rayleigh wave tomography of New Zealand   总被引：16，自引：0，他引：16  

Fan-Chi Lin  Michael H. Ritzwoller  John Townend  Stephen Bannister  Martha K. Savage 《Geophysical Journal International》2007,170(2):649-666

We present the first New Zealand-wide study of surface wave dispersion, using ambient noise observed at 42 broad-band stations in the national seismic network (GeoNet) and the Global Seismic Network (GSN). Year-long vertical-component time-series recorded between 2005 April 1 and 2006 March 31 have been correlated with one another to yield estimated fundamental mode Rayleigh wave Green's functions. We filter these Green's functions to compute Rayleigh wave group dispersion curves at periods of 5–50 s, using a phase-matched filter, frequency–time analysis technique. The uncertainties of the measurements are estimated based on the temporal variation of the dispersion curves revealed by 12 overlapping 3-month stacks. After selecting the highest quality dispersion curve measurements, we compute group velocity maps from 7 to 25 s period. These maps, and 1-D shear wave velocity models at four selected locations, exhibit clear correlations with major geological structures, including the Taranaki and Canterbury Basins, the Hikurangi accretionary prism, and previously reported basement terrane boundaries.  相似文献