A Preliminary Report on Yong＇anpu Tectonic Window in Suizhong County, Western Liaoning Province

For understanding the Mesozoic tectonics of Yanshan （燕山 ） belt, the authors took geological mapping in the belt. A large-scale thrust structure was identified in Yonganpu （永安堡） area. in the western part of Suizhong （绥中 ） County, Liaoning （辽宁 ） Province during our recent mapping in the Yanshan belt. The hanging wall of the thrust was composed of Archean gneiss and the overlying Early Cretaceous Zhangjiakou （张家口 ） Formation; meanwhile, the strongly ductile deformed volcanic rocks of Zhangjiakou Formation comprised the footwall in Yong＇anpu tectonic window. This discovery indicates the existence of strongly contractional deformation in the Yanshan belt after the eruption of Early Cretaceous Zhangjiakou volcanic rocks. On the basis of mapping and research, it is concluded that the published official geological maps have failed to identify the major structural features of the Yanshan belt.     

Nd Isotopes and Geochemistry of Phanerozoic Clastic Sedimentary Rocks from the Yangtze Block and Their Tectonic Implications

This article presents Sm-Nd and geochemical data on fine-grained sediments of the northern margin from the Yangtze block, China, to understand the variations of Nd isotopic compositions and crustal evolution history in this area. The results are as follows: (1) Nd isotopic compositions for clastic sedimentary rocks of the Middle-Late Proterozoic have relatively positive Nd(t) values ( 2.72 to 0.69), with Nd model ages from 1.38 Ga to 1.55 Ga, corresponding to the contemporaneous volcanic rocks from the Xixiang (西乡) Group. This indicates that the arc-related materials from Middle-Late Proterozoic dominate the provenances of the Middle-Late Proterozoic periods. (2) The gradual decrease in εNd(t) during the Cambrian-Carboniferous periods is likely to reflect the progressively increasing proportion of erosion materials from the Foping (佛坪) and Qinling (秦岭) complexes, corresponding to a gradually decreasing trend in the La/Th ratios. (3) A prominent increase in the εNd(t) value of the Late Permian strata probably reflects the significant incorporation of the mantle-derived materials. The trace element data are compared with data of the Emeishan (峨嵋山) flood basalts. These data indicate that the volcanic dust has been added to the Late Permian strata during the Late Permian, represented by periods of extremely high Emeishan flood basalt activity in the south-eastern margin of the Yangtze block.     

Plesiosaurs

Plesiosaurs are an unusual and intriguing group of extinct aquatic reptiles ( Fig. 1 ). They are sauropterygians, a group known from an array of semi‐aquatic forms during the Triassic period: placodonts, pachypleurosaurs and nothosaurs. The first plesiosaurs are known from the very latest Triassic, but by the Early Jurassic plesiosaurs were cosmopolitan in distribution and lasted successfully to the latest Cretaceous, when they became victims of the K‐T extinction event. Plesiosaurs were predominantly marine organisms, although their fossils are not uncommon in brackish or even fresh water deposits. We know that all plesiosaurs were carnivorous; many of them were top predators in their respective ecosystems. But with no living descendants (or analogues) plesiosaurs are mysterious fossil organisms—as we will see, many questions regarding their biology remain unanswered or contentious. However, plesiosaurs are currently undergoing renewed scientific attention.

Figure 1 Open in figure viewer PowerPoint The beautifully preserved skeleton of the plesiosaur Rhomaleosaurus victor seen in ventral view, from the Lower Jurassic (Toarcian) of Holzmaden, Germany (total length 3.44 m). Redrawn from Fraas (1910).     

Continental construction in Central Asia and actualistic comparisons with western Pacific: Preface

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Elevated passive continental margins: Numerical modeling vs observations. A comment on Braun (2018)

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中国大陆科学深钻发展的若干思考与建议

科学钻探是获取地球内部信息的最直接和最重要手段,在解决“向地球深部进军”战略科技问题上起着无可替代的作用。本文简要回顾国内外大陆科学钻探的发展历程和深钻的发展现状,分析大陆科学深钻发展特点与态势;围绕中国大陆科学深钻,梳理其关键科学技术问题、面临的挑战与机遇;在此基础上提出中国大陆科学深钻发展的目标、优先发展方向与发展途径建议。大陆科学深钻能够为地球动力学过程、地质灾害、地质资源和环境变化等全球关注的地球科学前沿问题提供独特的研究途径,但是其实施深度又受超高温和超高压等恶劣井眼环境的制约;现代科学技术的进步有力促进了大陆科学深钻中各项技术的发展,为超深井和特深井科学钻探提供重要支撑。中国大陆科学深钻应以9000～15000 m特深井为目标,注重“超深”“深时”和“深观”等领域的科学问题,优先发展地球深部构造、深部生命、深时气候和深部资源探测等方向,研究超深物质、动力学过程和岩石物理等实验技术,研发超高温超高压环境下的钻井、测井和长期观测等技术与装备,促使我国深地探测能力和水平实现一次飞跃。     

Origin and quantitative source assessment of deep oils in the Tazhong Uplift,Tarim Basin

A large amount of deep oil has been discovered in the Tazhong Uplift, Tarim Basin whereas the oil source is still controversial. An integrated geochemical approach was utilized to unravel the characteristics, origin and alteration of the deep oils. This study showed that the Lower Cambrian oil from well ZS1C (

_1x) was featured by small or trace amounts of biomarkers, unusually high concentration of dibenzothiophenes (DBTs), high δ³⁴S of DBTs and high δ¹³C value of n-alkanes. These suggest a close genetic relationship with the Cambrian source rocks and TSR alteration. On the contrary, the Middle Cambrian oils from well ZS1 (

_2a) were characterized by low δ¹³C of n-alkanes and relatively high δ³⁴S of individual sulfur compounds and a general “V” shape of steranes, indicating a good genetic affinity with the Middle–Upper Ordovician source rocks. The middle Cambrian salt rock separating the oils was suggested to be one of the factors responsible for the differentiation. It was suggested that most of the deep oils in the Tazhong Uplift were mixed source based on biomarkers and carbon isotope, which contain TSR altered oil in varied degree. The percentage of the oils contributed by the Cambrian–Lower Ordovician was in the range of 19–100% (average 57%) controlled by several geological and geochemical events. Significant variations in the δ³⁴S values for individual compounds in the oils were observed suggesting a combination of different extent of TSR and thermal maturation alterations. The unusually high DBTs concentrations in the Tazhong-4 oilfield suggested as a result of mixing with the ZS1C oil (

_1x) and Lower Ordovician oils based on δ³⁴S values of DBT. This study will enhance our understanding of both deep and shallow oil sources in the Tazhong Uplift and clarify the formation mechanisms of the unusually high DBTs oils in the region.     

Acyclic Alkanes in the Cave in Qingjiang, Soil over Heshang Hubei Province

The reports that relate to the biomarker＇s fate and characteristics of the modern soil in the karst area are very lacking. By using gas chromatography-mass spectrometry （GC-MS）, a series of biomarkers were identified from the soils collected over Heshang cave （和尚洞） in Qingjiang （清江）, Hubei （湖北） Province. The distribution of n-alkanes is mainly from C2s to C33 in carbon number, with a maximum at C31. They have a strong odd-over-even carbon number predominance. These characteristics represent an input mainly from higher plants. The lipid parameters, including CPIh （carbon preference index）, Rb/t（ratio of lower- to higher-molecular-weight homologues） and ACL （average chain length）, show comparable trends with depth, probably reflecting vegetation change and microbial degradation. Series of monomethylalkanes and diploptene are present in the extractable organic matter; they might be derived from soil microbes, cyanobacteria in particular.     

Japan's Tohoku Earthquake and Tsunami

The magnitude 9.0 Tohoku or Sendai Earthquake ( Fig. 1 ) struck just off the northeast coast of Honshu, Japan on 11 March 2011 making it the fourth largest earthquake to be recorded since 1900, and the largest Japanese earthquake since modern seismometers were developed 130 years ago. Despite the earthquake being much more powerful than had been expected from the subduction zone east of Honshu, the earthquake preparedness of Japan resulted in relatively little earthquake damage—despite the protracted shaking with ground accelerations up to three times that of gravity. However, it was the resulting 10–15 metre high tsunami waves that wreaked havoc along the coastal plain, resulting in a death toll in the tens of thousands and an on‐going drama at the Fukushima I nuclear power plant. Modern seismology has its origins in the analyses of the 1906 San Francisco and 1923 Great Kanto earthquakes. The 2011 Tohoku (or ‘northeast’) earthquake looks set to similarly significantly advance our understanding of earthquakes and tsunamis due to the unprecedented volume of seismic, GPS, tide gauge and video data available. There is much information to be gained on how large earthquakes rupture, how buildings behave under prolonged severe shaking and how tsunamis propagate.

Figure 1 Open in figure viewer PowerPoint Tohoku earthquake global displacement wavefield from IRIS. http://www.iris.edu/hq/files/iris_news/images/Sendai_RS.jpg     

Genesis of Sr Isotopes in Groundwater of Hebei Plain

To analyze the genesis of Sr isotopes in groundwater of Hebei plain, time-accumulative effect of 87Sr/86Sr ratio was studied. It is shown that 87Sr/86Sr ratio increases with the increasing age and depth of groundwater and has a positive correlation to 4Heexc and a negative correlation to δ18O and δD. The groundwater is divided into three groups to discuss the relation between 87Sr/86Sr ratio and Sr2 content: ① moderate Sr2 content and higher 87Sr/86Sr ratio (water I); ② lower Sr2 content and higher 87Sr/86Sr ratio (water II); and ③ higher Sr2 content and lower 87Sr/86Sr ratio (water III), that is hot water. On the basis of integrated analysis, it was considered that ① the radiogenic Sr in the Quaternary groundwater (Q4-Q1) originates from weathering of silicate rich in Na and Rb, mainly from plagioclase; ② the radiogenic Sr of hot water in Huanghua port is attributed to carbonate disso- lution, with lower 87Sr/86Sr ratio and higher Sr/Na ratio; ③ the recharge area is laterally recharged by the groundwater flowing through igneous and metamorphic rocks, with moderate 87Sr/86Sr ratio. How- ever, the formation mechanism of Sr isotopes in Tertiary groundwater needs further studies.     

The Haiti Earthquake: a salutary lesson in (non) earthquake engineering

A devastating earthquake of magnitude 7 struck very close and almost beneath Port au Prince the capital of Haiti, the western half of the island of Hispaniola, early in the morning of Tuesday, 12 January 2010 ( Fig. 1 ). While in absolute terms this was by no means the largest earthquake recorded this year globally, the death toll is around 230 000, making it one of the world's worst earthquakes in terms of casualties in recorded history, with almost uncountable economic loss to one of the poorest countries in the world.

Figure 1 Open in figure viewer PowerPoint Intensity map of 2010 Haiti earthquake (Image: USGS).     

REE geochemistry and isotopic data of Archean silicic volcanics and granitoids from the Pilbara Block,Western Australia: implications for the early crustal evolution

Eighteen silicic volcanic rocks of the Warrawoona Group and ten associated plutonic rocks from the Pilbara Block, Western Australia, have been chosen for geochemical and isotopic studies. Silicic volcanics of the UNSB (Upper member of North Star Basalt) are dated at 3.56—3.57

, by both the Rb-Sr and the Sm-Nd methods. The respective 1 (initial isotopic composition) values are 0.7005 ± 5 (Sr) and 0.50810 ± 39 (Nd). This age is consistent with the stratigraphic interpretation that the TalgaTalga Subgroup, in which the North Star Basalt occupies the lowermost position, is overlain by the Duffer Formation, whose age was earlier established at 3.45

by the zircon U-Pb method. The new Rb-Sr data on six silicic lava samples from the Duffer Formation yield an isochron of 3.23 ± 0.28 (2v). Though imprecise, this age agrees with the zircon age within error limits. Rb-Sr ages of 2.3–2.4.

obtained for the ‘Panorama’ rocks and the Wyman Formation do not correspond to their initial eruption ages. Chemical arguments suggest that these ages represent the time of metasomatism associated with the widespread thermal event in this region about 2.3–2.4

ago.Geochemically, most of these analyzed rocks (volcanic and plutonic) are of tonalite-trondhjemitegranodiorite (TTG) composition, a typical feature found in many other Archean terrains. They generally show fractionated REE patterns, except the Panorama Formation rocks. Furthermore, the Wyman Formation rhyolites and the post-tectonic adamellites show significant negative Eu anomalies, suggesting a similar mode of magma generation and a probable genetic link. Theoretical considerations suggest that most of these TTG rocks could have been generated by partial melting of amphibolitic or basaltic sources, followed by fractional crystallization.Although the Archean granitic gneisses often possess mantle-like I_sr values, the trace element data indicate that they could not have been derived by direct melting of upper mantle materials. The immediate tectonic implication is that in any Archean terrain, the formation of Na-rich continental crust of TTG suite must be preceded by the presence of basaltic crust. The occurrence of this basaltic crust is a matter of controversy. Such crust might have been totally destroyed by repeated melting processes, or its remnants are now represented by some of the mafic-ultramafic enclaves within the tonalite-trondhjemite batholiths.     

http://www.sciencedirect.com/science/article/pii/S1674987112000874

<正>1.Introduction The continental crust,covering nearly a third of the Earth's surface,is dominantly made up of granites and granodiorites(Rudnick and Gao, 2003).Although the vast majority of these granitoids are amphiboleand /or biotite-bearing,orthopyroxene-bearing granitoids form a minor but important component of the lower continental crust in many high-grade terrains(e.g.,Bohlender et al.,1992;Kilpatrick and Ellis,1992;Sheraton et al.,1992;Berger et al.,1995;Zhou et al., 1995;Peucat et al.,1996;Duchesne and Wilmart,1997;Hughes et al.,1997;Prame.1997;Frost et al.,2000;Janasi,2002;Mendes     

The Gash Breccias of the Pembroke Peninsula,SW Wales

The thickest development of Carboniferous Limestone in Great Britain (about 1200 m) is in the Pembroke Peninsula of SW Wales. In various places, the regularity of the normally well‐stratified limestone is broken by zones of disturbance, which are spectacularly displayed in magnificent near‐vertical cliff sections. The zones generally occupy the whole of the 50 m‐high cliffs and are up to 300 m wide. The chief component of these zones is a chaotic, clast‐supported breccia, composed of angular limestone fragments welded together with varying degrees of firmness by sparry calcite veining or a normally sparse, red‐pink sandy or silty matrix. The breccias are very easy to distinguish and form a striking contrast to the grey cliff scenery hereabouts ( Figs 1, 2 ), yet they have not been discussed much—until now.

Figure 1 Open in figure viewer PowerPoint Location map, showing localities mentioned in the text, the outcrop of the Carboniferous Limestone, the chief synclinal axes and the distribution envelope of the Gash Breccias (after Thomas 1971 ). 1. Flimston Bay; 2. Bullslaughter Bay (west); 3. Bullslaughter bay (east); 4. Trevallen; 5. Box Bay; 6. Draught; 7. Whitesheet Rock; 8. Lydstep Point; 9. St Margaret's Point; 10. Den Point; 11. Valleyfield Top; 12. Pembroke Castle.     

From clergymen to computers—the advent of virtual palaeontology

Palaeontology was established as a science in the Victorian era, yet has roots that stretch deeper into the recesses of history. More than 2000 years ago, the Greek philosopher Aristotle deduced that fossil sea shells were once living organisms, and around 500 ad Xenophanes used fossils to argue that many areas of land must have previously been submarine. In 1027, the Persian scholar Avicenna suggested that organisms were fossilized by petrifying fluids; this theory was accepted by most natural philosophers up until the eighteenth century Enlightenment, and even beyond. The late 1700s were notable for the work of Georges Cuvier who established the reality of extinction. This, coupled with advances in the recognition of faunal successions made by the canal engineer William Smith, laid the framework for the discipline that would become known as palaeontology. As the nineteenth century progressed, the scientific community became increasingly well organized. Most fossil workers were gentleman scientists and members of the clergy, who self‐funded their studies in a new and exciting field. Many of the techniques used to study fossils today were developed during this ‘classical’ period. Perhaps the most fundamental of these is to expose a fossil by splitting the rock housing it, and then conduct investigations based upon the exposed surface ( Fig. 1 ). This approach has served the science well in the last two centuries, having been pivotal to innumerable advances in our understanding of the history of life. Nevertheless, there are many cases where splitting a rock in this way results in incomplete data recovery; those where the fossils are not flattened, but are preserved in three‐dimensions. Even the ephemeral soft‐tissues of organisms are occasionally preserved in a three‐dimensional state, for example in the Herefordshire, La Voulte Sûr Rhone and Orsten ‘Fossil Lagerstätten’ (sites of exceptional fossil preservation). These rare and precious deposits provide a wealth of information about the history of life on Earth, and are perhaps our most important resource in the quest to understand the palaeobiology of extinct organisms. With the aid of twenty‐first century technology, we can now make the most of these opportunities through the field of ‘virtual palaeontology’—computer‐aided visualization of fossils.

Figure 1 Open in figure viewer PowerPoint A split nodule showing the fossil within, in this case a cockroachoid insect. Fossil 4 cm long (From Garwood & Sutton, in press ).     

M25 roadworks reveal earliest UK Neanderthal occupation at Dartford

As anyone travelling on the roads of southeast England between 2006 and 2008 has probably been aware, major improvements have recently been made at the junction of the M25 and A2 motorways, south of the main Dartford crossing of the River Thames ( Fig. 1 ). The roadworks, funded by the UK Highways Agency, with the main contractors Jacobs Babtie and Costain, were accompanied by archaeological investigations carried out by Oxford Archaeology between 2003 and 2006. The archaeological programme had a major Palaeolithic/Pleistocene element under my direction ( Fig. 2 ) that has produced evidence of Neanderthal occupation early in the last glaciation (the Devensian, which lasted from 115 000 to 10 000 bp ), during a period when Britain had until now, been thought to have been entirely deserted.

Figure 1 Open in figure viewer PowerPoint Site location and areas of investigation.     

Sanmenxia Loess and Paleoenvironmental Change

INTRODUCTIONThe Sanmenxia area is located at the SE marginof the Loess Plateau,where a thick-layered loess de-posit developed(Fig.1).Previous research has al-ready been carried out on some loess stratigraphy inthe area(Teng,1988;Xie and Jiang,1987;Yue,1985,1984),which concentrated on petrostratigra-phy and magnetostratigraphy.Further environmentalinvestigation has not yet been pursued.After the ge-ological survey(Zheng et al.,1992;An et al.,1989;Ding and Liu,1989),more integrated str…     

国际大陆科学钻探（ICDP）进展

直接进入地球内部观察研究地球的成分、结构构造和各种地质作用是人类的长期梦想,就目前人类的科学技术条件,人们还不可能直接钻入地下进行实地取样与观察。科学钻探是获取地球深部物质、了解地球内部信息的最直接、最有效、最可靠的方法。国际大陆科学钻探计划成立以来,已经在许多领域取得了重要成果,发表了大量的文章。本文对科学钻探的发展过程、大陆科学钻探的意义、国际大陆科学钻探委员会成立的背景与建立过程、组织结构、立项程序、立项准则以及研究领域做了简要概述。对国际大陆科学钻探近年来在气候变化与全球环境、陨石撞击坑及撞击过程研究、地球生物圈、火山系统和热流机制、地幔柱和大洋裂谷、活动断裂、汇聚板块边界和碰撞带、自然资源等主要研究领域的重要进展做了综述,重点介绍了日本的云仙火山钻探项目、美国夏威夷火山科学钻探和圣安德列斯断裂深部观测计划的主要进展。概括和总结了中国实施的3个国际大陆科学钻探项目所取得的成果进展和中国的大陆科学钻探事业近期的主要活动。     

A blast from the past: the lost world of dinosaurs at Tendaguru,East Africa

The superbly preserved dinosaurs and associated organisms from the Late Jurassic fossil Lagerstätte Tendaguru in southern Tanzania mark an exceptional success story in palaeontology. The new permanent exhibits of the Museum für Naturkunde in Berlin, highlighting the spectacular dinosaurs ( Fig. 1 ), are telling evidence. In more than 100 years of research, geoscientists produced a considerable amount of knowledge about the composition and diversity of the ancient fauna and flora at Tendaguru, their unique palaeobiological characteristics, and the continental to marginal marine ecosystems in which they lived. Several questions are still open to debate. These include the detailed genesis of the Lagerstätte, aspects of dinosaur palaeobiology, and their biogeographical affinities to contemporaneous assemblages from the Northern Hemisphere.

Figure 1 Open in figure viewer PowerPoint The discovery of Brachiosaurus was the crowning achievement of the German Tendaguru expedition of 1909–1913. The skeleton is about 13 metres tall and 23 metres long. It is on display in the dinosaur hall of the Museum für Naturkunde (MfN) in Berlin along with Dicraeosaurus, Kentrosaurus, Dysalotosaurus and Elaphrosaurus. They constitute the most significant dinosaur discoveries ever made in Africa. Photo: Antje Dittmann, MfN.