An historical review of landslide research in the South Wales coalfield

Summary The areal density of landslides in the coalfield of South Wales is one of the highest in the UK. During the past 100 years landsliding has had considerable impact, causing structural damage and loss of life. Most of the landslides were initiated under periglacial conditions but many became reactivated due to the activities of humans, particularly during the late 19 th century when widespread urban and industrial development commenced in the Welsh valleys. A number of the area's larger landslides are first-time slides which occurred during the past 100 years. This paper sets out to chart the history of landslide research in the coalfield, which began through work by mining engineers.     

磷灰石裂变径迹分析（AFTA）——一种研究含油气盆地古热构造史的新方法

磷灰石裂变径迹分析近年来广泛地被用来研究含油气盆地古热定史与古构造史及指导油气勘探，这主要是根据磷灰石裂变径迹退火是时间和温度的函数，而烃的生成与热成熟同是也是和温度的函数，而且磷灰石裂变径迹退火温度范围与石油的生成门限相吻合，退火除受温度、时间影响外、还受化学成分，取向因素控制。ＡＦＴＡ包括裂变径迹年龄分析和裂变径迹长度分析，通过前者可获得退火方面信息，通过后者可获得最大古地温及其随时间的变化及     

Late Holocene climate change and human disturbance on Andros Island, Bahamas

A 2 m sediment core from Church's Blue Hole on Andros Island, Bahamas provides the first paleoecological record from the Bahama Archipelago. The timing of events in the lower portion of the core is uncertain due to inconsistencies in the radiocarbon chronology, but there is evidence that a late Holocene dry period altered the limnology of Church's Blue Hole and supported only dry shrubland around the site. The dry period on Andros may correlate with a widespread dry period in the Caribbean from 3200 to 1500 yr BP. After the dry period ended, a more mesic climate supported tropical hardwood thicket around Church's Blue Hole. At c. 740 radiocarbon yr BP there is a sudden rise in charcoal concentration and a rapid transition to pinewoods vegetation, while at c. 430 radiocarbon yr BP charcoal concentration drops, but is higher again near the top of the core. Although climatic shifts could have caused these changes in vegetation and charcoal concentration, the changes post-date human colonization of the Bahamas and may reflect human arrival, followed by the removal of humans c. 1530 AD and the recolonization of Andros Island c. 200 years later.This is the 12th in a series of papers published in this special AMQUA issue. These papers were presented at the 1994 meeting of the American Quaternary Association held 19–22 June, 1994, at the University of Minnesota, Minneapolis, Minnesota, USA. Dr Linda C. K. Shane served as guest editor for these papers.     

魏晋南北朝测绘史考

概述魏晋南北朝时期的测绘管理及职官设置，疆域测量了及地图绘制，天文观测及其新发现等史实，勾画出了这一时期测绘发展的轮廓。     

Late-glacial paleoenvironment of Lake Algonquin sediments near Clarksburg,Ontario

Excavation below the Lake Algonquin gravel beach bar near Clarksburg, Ontario, exposed mollusc-bearing clay over a lens of plant debris. This is the northernmost and most deeply buried Lake Algonquin fossil site found thus far in Ontario. It is the first site to provide dates from directly below the Algonquin beach bar. Two radiocarbon dates of about 11 200 years confirm the age of isostatically transgressing Lake Algonquin. Plant macrofossils (21 taxa), pollen (39 taxa), molluscs (12 taxa), and ostracodes (18 taxa) indicate that the climate was colder than present by several degrees and the forest-tundra ecotone was nearby initially but retreated northward rather quickly. Upward increases in abundances and diversity of molluscs and ostracodes suggest it was a time of rapid migration and colonization of species.Deceased, 1 November 1994This is the 7th in a series of papers published in this special AMQUA issue. These papers were presented at the 1994 meeting of the American Quaternary Association held 19–22 June, 1994, at the University of Minnesota, Minneapolis, Minnesota, USA. Dr Linda C. K. Shane served as guest editor for these papers.     

Superwaves and superfloods: The bombardment hypothesis and geomorphology

The bombardment of the oceans by asteroids and comets leads to the propagation of very large waves—superwaves. On approaching continental margins, superwaves may grow to heights large enough to spill on to the land, flooding extensive areas of continental lowland. The waters from these superfloods, in running back to the sea, would be capable of carrying out enormous amounts of work, possibly diverting rivers, cutting gorges, forming valley meanders, and leading to the widespread aggradation of coarse deposits produced by incoming superwaves stripping the soil and regolith cover and denuding weathered bedrock. Calculations of the magnitude and frequency of superfloods, based on current asteroidal impact rates, indicate that the superflooding of continental margins, including the British Isles, could have occurred several times since the start of the Pliocene. Thus, there seems to be a case for reviving some of the views of the old diluvialists, and exploring the worth of neodiluvialism as a system of Earth surface history.     

攀西裂谷火成岩组合的矿物学、岩石学特征及其与裂谷演化的关系

攀枝花—西昌地区的火成岩组合是裂谷岩浆作用的主要产物。它们可以分为裂谷期前组合、裂谷早期组合、中期组合和晚期组合。通过火成岩组合的矿物学、岩石学研究,可以推断攀西裂谷演化的历史。     

Earlier days of gravity waves revisited

The means whereby the author came to be involved in the study of atmospheric gravity waves, and then came to involve others in that study, are outlined. In particular, events leading up to, during and following the International Symposium on Fluid Mechanics in the Ionosphere, of July 1959, are described.     

Effect of eutrophication on species composition and growth of freshwater mussels(Mollusca,Unionidae) in Lake Hallwil (Aargau,Switzerland)

Species composition, relative abundance and life history of unionid mussels are compared between 1982–86 and 1915–19 in Lake Hallwil and the outflowing brook. The recent samples of unionid mussels were collected by divers, whereas the older ones were from a shell collection. The motivation for the comparison was that the trophic degree of the lake has changed since the beginning of the century from mesotrophic to highly eutrophic. The effects of this increased trophic degree of the lake on the life cycle of unionid mussels is discussed. Predictions are made about species composition and life history in the context of the ongoing lake restoration by the authorities.