A lunar cryptomare dome near Mee H and Drebbel F

In this study, we examine the lunar mare dome Mee 1 situated near the craters Mee H and Drebbel F in a region showing evidence of ancient (pre-Orientale) mare volcanism and cryptomare deposits. Regional stratigraphic relations indicate that Mee 1 was formed prior to the Orientale impact at the beginning of the Imbrian period. Based on a combined photoclinometry and shape from shading technique applied to telescopic CCD images of the dome acquired under oblique illumination, we determined a diameter of Mee 1 of 25 km, a height of 250 m, a flank slope of 1.15^°, and a volume of . Based on rheologic modelling of the dome and a viscoelastic model of the feeder dike, we obtained a magma viscosity of , an effusion rate of , a duration of the effusion process of 1.6 years, a magma rise speed of , a width of the feeder dike of 32 m, and a horizontal dike length of 144 km. A comparison of Mee 1 with domes with similar morphometric properties, which are located near Milichius and inside the crater Petavius, reveals strong similarities with respect to the viscosity of the dome-forming magma and the feeder dike geometry, while the effusion rate and magma rise speed of Mee 1 are somewhat higher. The pronounced morphometric differences between Mee 1 and a smaller dome situated close to the crater Doppelmayer and characterised by a similar magma viscosity suggest that the growth of that dome was limited by exhaustion of the magma reservoir, while Mee 1 and the other larger domes display morphometric properties presumably coming closer to the cooling limit. The comparison of the ancient dome Mee 1 with the younger (Eratosthenian) edifices near Milichius and Doppelmayer suggests that the conditions in the upper mantle and the crust favoured high eruption volumes, effusion rates, and magma rise speeds, implying the occurrence of large magma reservoirs preventing the limitation of dome growth by magma exhaustion. On the other hand, we observe similar general morphometric, rheologic, and feeder dike characteristics and, thus, conclude that the formation conditions of lunar mare domes did not change fundamentally during the Imbrian period.     

Lunar intrusive domes: Morphometric analysis and laccolith modelling

This study examines a set of lunar domes with very low flank slopes which differ in several respects from the frequently occurring lunar effusive domes. Some of these domes are exceptionally large, and most of them are associated with faults or linear rilles of presumably tensional origin. Accordingly, they might be interpreted as surface manifestations of laccolithic intrusions formed by flexure-induced vertical uplift of the lunar crust (or, alternatively, as low effusive edifices due to lava mantling of highland terrain, or kipukas, or structural features). All of them are situated near the borders of mare regions or in regions characterised by extensive effusive volcanic activity. Clementine multispectral UVVIS imagery indicates that they do not preferentially occur in specific types of mare basalt. Our determination of their morphometric properties, involving a combined photoclinometry and shape from shading technique applied to telescopic CCD images acquired at oblique illumination, reveals large dome diameters between 10 and more than 30 km, flank slopes below 0.9°, and volumes ranging from 0.5 to 50 km³. We establish three morphometric classes. The first class, In1, comprises large domes with diameters above 25 km and flank slopes of 0.2°-0.6°, class In2 is made up by smaller and slightly steeper domes with diameters of 10-15 km and flank slopes between 0.4° and 0.9°, and domes of class In3 have diameters of 13-20 km and flank slopes below 0.3°. While the morphometric properties of several candidate intrusive domes overlap with those of some classes of effusive domes, we show that a possible distinction criterion are the characteristic elongated outlines of the candidate intrusive domes. We examine how they differ from typical effusive domes of classes 5 and 6 defined by Head and Gifford [Head, J.W., Gifford, A., 1980. Lunar mare domes: classification and modes of origin. Moon Planets 22, 235-257], and show that they are likely no highland kipukas due to the absence of spectral contrast to their surrounding. These considerations serve as a motivation for an analysis of the candidate intrusive domes in terms of the laccolith model by Kerr and Pollard [Kerr, A.D., Pollard, D.D., 1998. Toward more realistic formulations for the analysis of laccoliths. J. Struct. Geol. 20(12), 1783-1793], to estimate the geophysical parameters, especially the intrusion depth and the magma pressure, which would result from the observed morphometric properties. Accordingly, domes of class In1 are characterised by intrusion depths of 2.3-3.5 km and magma pressures between 18 and 29 MPa. For the smaller and steeper domes of class In2 the magma intruded to shallow depths between 0.4 and 1.0 km while the inferred magma pressures range from 3 to 8 MPa. Class In3 domes are similar to those of class In1 with intrusion depths of 1.8-2.7 km and magma pressures of 15-23 MPa. As an extraordinary feature, we describe in some detail the concentric crater Archytas G associated with the intrusive dome Ar1 and discuss possible modes of origin. In comparison to the candidate intrusive domes, terrestrial laccoliths tend to be smaller, but it remains unclear if this observation is merely a selection effect due to the limited resolution of our telescopic CCD images. An elongated outline is common to many terrestrial laccoliths and the putative lunar laccoliths, while the thickness values measured for terrestrial laccoliths are typically higher than those inferred for lunar laccoliths, but the typical intrusion depths are comparable.     

The Swedish Deep Drilling Program: the quest for the Earth's inner secrets

The Swedish Deep Drilling Program (SDDP) has been initiated to study fundamental problems of the dynamic Earth system, its natural history and evolution. Many key scientific questions can be addressed through in situ investigations only, requiring deep continental drilling. Some are unique to Scandinavia, most are of international interest and significance. At present, five core projects ( Fig. 1 ) with international teams are integrating scientific problems with societal and industrial applications. If SDDP succeeds to attract the funding required, Sweden will have a number of world‐class boreholes at key locations by 2020.

Figure 1 Open in figure viewer PowerPoint Locations of SDDP drilling project proposals. PFDP—Postglacial Fault Drilling Project; PaMVAS—Palaeoproterozoic mineralized volcanic arc systems: the Skellefte District; COSC—Collisional Orogeny in the Scandinavian Caledonides; DRL—The Dellen Impact Crater, a geoscientific deep rock laboratory; SELHO—Svecofennian accretion, an example of the early structural evolution in a large hot orogen; CISP—Concentric Impact Structures in the Palaeozoic: the Lockne and Siljan craters. Background and inset image from Blue Marble Next Generation data set (NASA Earth Observatory, http://earthobservatory.nasa.gov/Features/BlueMarble/ ).     

The Sedimentological Knowledge Tree:Significance,Method and Progress

正On the platform of the Deep-time Digital Earth Program(DDE),sedimentary data are essential for achieving its scientific objectives.These data will take stratigraphic units as their core data carrier,for quantitative or qualitative data analysis.The DDE Sedimentary Data Group is responsible for the management of the sedimentary data on the DDE platform and has now developed into a group of nearly 40 disciplinary experts.This groups main tasks are constructing sedimentary knowledge     

论江西气象科技创新体系改革与建设

对江西气象科技创新体系改革与建设的内容和方向进行了论述,认为江西气象科技创新体系改革与建设,应坚持“自主创新,重点跨越,支撑发展,引领未来”的科技发展方针,明确科技型、基础性社会公益事业定位,深入实施科技兴气象战略,深化气象科技体制改革,加强原始创新、集成创新和引进消化吸收再创新;促进业务与科研的结合,形成科技创新引领事业发展的研究型业务,提升气象科技创新能力,提高气象科技水平和气象业务的科技含量,提高气象队伍素质,培养造就具有创新能力、既懂科研又懂业务的学科、技术带头人和复合型人才。     

一个考虑SST变化的月数值预报结果分析

根据陈隆勋等对海温月季变化研究的结果提出除了从冬到春的过渡月份外,ＳＳＴ距平的相邻月的月际变化不大。在此基础上,选了１９９６年６月并利用ＣＣＭ１动力气候模式作了月数值预报。在预报中,利用１９９６年６月１日００Ｚ中国国家气象中心Ｔ６４的客观分析资料作初值,利用１９９６年５月的ＳＳＴ距平加到６月气候ＳＳＴ作为６月的ＳＳＴ,作了一个月数值预报。结果表明,考虑了ＳＳＴ变化的数值预报优于用气候海温作的数值预报。前者的５００ｈＰａ高度场预报距平、８５０ｈＰａ纬向风预报距平、中国地区气温预报距平和降水预报距平分布均十分接近于实际观测分布。     

Agro-industrial conventions: some evidence from northern California's wine industry

Research into learning, innovation, and clustering suggests that local socioeconomic practices, or conventions, are critical to economic growth and regional development. Yet when it comes to the wine industry, explanations of economic success often focus on natural advantages. This article seeks to address this issue, presenting findings on the local practices of wine producers in northern California. The argument is that there are important local social and industrial linkages that bolster the competitiveness of California's wine industry and serve to upgrade production practices. This article highlights the career histories and perceptions of several key informants who are offered as exemplars of more commonly shared industrial experience and practice.     

The reflection seismic survey of project TIPTEQ—the inventory of the Chilean subduction zone at 38.2° S

We describe results of an active-source seismology experiment across the Chilean subduction zone at 38.2°S. The seismic sections clearly show the subducted Nazca plate with varying reflectivity. Below the coast the plate interface occurs at 25 km depth as the sharp lower boundary of a 2–5 km thick, highly reflective region, which we interpret as the subduction channel, that is, a zone of subducted material with a velocity gradient with respect to the upper and lower plate. Further downdip along the seismogenic coupling zone the reflectivity decreases in the area of the presumed 1960 Valdivia hypocentre. The plate interface itself can be traced further down to depths of 50–60 km below the Central Valley. We observe strong reflectivity at the plate interface as well as in the continental mantle wedge. The sections also show a segmented forearc crust in the overriding South American plate. Major features in the accretionary wedge, such as the Lanalhue fault zone, can be identified. At the eastern end of the profile a bright west-dipping reflector lies perpendicular to the plate interface and may be linked to the volcanic arc.     

地震预报实验场:科学问题与科学目标

本文简要回顾了以往地震预报实验场的经验教训,讨论了新一代地震预报实验场的实施策略。汲取汶川地震的经验启示,本文提出"地震博弈"策略,即考虑中长期地震预测的可用性与不确定性,在监测与实验系统设计中考虑地震活动和地震构造相依的区域模型。对于特定的活动断裂或活动地块边界带的潜在强震段落,设置适应多种孕震模型的"想定地震破裂",针对地震孕育的"想定模式"设计观测项目和监测系统。这一系统以地震成因和孕震模型的有效约束、"预期"前兆的有效监测、预测/预报效能的有效检验为导向。从技术角度,本文提出将地震预报实验场作为一个"大科学工程",强调复杂的多层次、多组分技术系统性能的稳健性,以及为确保与地震有效的"近距离接触"的系统可持续性。     

伊兹米特地震的几点启示

土耳其伊兹米特Ｍｓ７．４地震后,中国地震局于１９９９年８月２５日派出了以张国民教授为团长的由７人组成的赴土耳其地震现场考察专家组。他们到地震现场进行了考察,从该震中得到了几点启示。