bluuebunny/crossref_metadata_2025 huggingface dataset:
The General Characteristics and Distribution of the Glaucophane‐Schist Belts of China
Authors: Shenbao Dong
Published: August 2010

Abstract On the basis of the temperature variation, the glaucophane‐schist facies can be classified into two facies groups, the glaucophane‐lawsonite facies group and the glaucophane‐greenschist facies group, and forms various facies series with other metamorphic facies. Glaucophane‐schist belts of China are of different types with regard to their average T‐ P gradients and tectonic environments. They are: (1) Proterozoic intracratonic glaucophane‐ schist belts, (2) Caledonian intracratonic glaucophane‐ schist belts, (3) Palaeozoic pericratonic glaucophane‐ schist belts along the northern margin of the Chinese Platform, and (4) Meso‐ Cenozoic glaucophane‐schist belts related to subduction.

The initiation and evolution of glaucophane‐schist metamorphism are related to their tectonic environments. Most glaucophane‐schist belts of China were formed in sialic environments. First the crust began to break up and eventually oceanic crust was formed. It seems that a non‐uniformitarian mechanism may be involved as this evolution is related to the change of the configuration of the heat flow within the crust.
Redetermination of the Crystal Structure of Vesignieite
Authors: Zhesheng Ma , Ruilin He , Xiaoling Zhu
Published: August 2010

Abstract Vesignieite, Cu3Ba(VO4)2(OH)2, crystallizes in space group C2/ m with a ° = 1.0270(2), b ° =0.5911(1), c° = 0.7711(2)nm and β =116.42(3)°. The intensity data were collected with the RIGAKU RASA‐IIS single‐crystal four‐circle diffractometer. The structure was determined by Patterson and Fourier methods and refined by the least‐square technique to a final R index of 0.051 for 614 independent diffraction points with |F| > 3σ| F|.

The crystal structure analysis shows that vesignieite has a layer structure parallel to (001).

The powder diffraction lines were reindexed.
The Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County, Yunnan Province
Authors: Daxian Zhao , Guangting Tang
Published: August 2010

Abstract Through studies on the element geochemistry, alteration of country rocks, ore‐forming fluids and isotope geochemistry of the Amo tin deposit in the metamorphic rocks of the Upper Proterozoic Ximeng Group, the authors consider that the concentration of the B‐F‐Li‐Rb‐Cs‐Sn association is related to acidic magmatism in the study area. The Fe‐ Mg‐ Li tourmaline in the ore is the replaced product of the country rocks by hypothermal fluid. The δ18O values of mineral separates are +2.01− +13.16%o and their δ34S values, +2.6−+7.2%o. The ore‐ forming materiais were derived from hydrothermal fluid of granitic magma. For the mineralization, the temperature is 450 ° ‐350°C, the pressure, 450‐1000 × 105 Pa, and the age, Himalayan (21.5 Ma). According to the geochemical characteristics, a minerogenic model is established: the deposit is a hypothermal cassiterite‐quartz vein type tin deposit controlled by the hidden Himalayan granites.
Fan‐Delta, Braid Delta and the Classification of Delta Systems
Authors: Xue Liangqing  , Galloway W.E.
Published: August 2010

Abstract This paper mainly discusses the origin and depositional features of fan‐deltas and braid deltas. Fan‐deltas are storm discharge‐dominated, while braid deltas are usually flashy flood‐dominated. The two types of delta, like common deltas, were reworked by marine processes. Delta systems are classified into nine delta types on the.basis of. the subaerial depositional processes and the nature of marine reworking.

Fan‐ deltas and braid deltas are of great significance for petroleum exploration. In divergent‐ margin foreland and intraplate rift‐subsided basin settings fan‐deltas often form combination traps for petroleum accumulation.
Precambrian Geochronology, Chronotectonic Framework and Model of Chronocrustal Structure of the Zhongtiao Mountains
Authors: Dazhong Sun , Huimin Li , Yuanxian Lin , Huifang Zhou , Fengqing Zhao , Min Tang
Published: August 2010

Abstract The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of various types of copper deposit. The rocks were dated using several dating methods. Based on the age data obtained by means of three methods, several aspects are dealt with: (1) the dating results obtained by different methods and their geological implications have been compared; (2) a chronotectonic framework has been constructed by means of these reliable ages, which indicates that the ages of the rocks of the Proterozoic mobile belt fall in a time span of 2400 to 2000 Ma during which global magmatic records are lacking and reflects the ages of important events in the mobile belt; (3) according to the ages of inherited zircons, neodymium model age of the depleted mantle sources (TDM) and geochemical and geological data, a model of Precambrian chronocrustal structure has been constructed, representing a typical for the North China craton.
Nd, Sr and O Isotopic Study on Spilite‐Keratophyre in Xiqiu, Zhejiang Province, China
Authors: Weizhou Shen , Bangtong Zhang , Hongfei Ling , Mingyuan Lai , Jiedong Yang , Xiancong Tao
Published: August 2010

Abstract Nd, Sr and O isotopic study on the spilite‐keratophyre sequence in Xiqiu shows that its ?Nd values are in the range of 4.02–5.26, and its ? sr values, +1.4‐2.6. According to the points of these data in the ? Nd‐T, ? Sr‐T and ? Nd‐? Sr diagrams, the spilite‐keratophyre is interpreted as being slightly contaminated by crustal materials. Its δ18O values are 3.9‐5.0%0. The depletion of 18O in the rocks resulted from the influence of seawater hydro thermal alteration during or soon after the rock formation. Based on the isotopic characteristics and available geochemical data, it is believed that the spilite‐keratophyre was formed in the well‐developed island‐ arc environment during the Late Proterozoic subduction of the palaeo‐ Pacific plate beneath the southeastern margin of the Yangtze massif.
Low‐Pressure Metamorphism of Granulite Facies in an Early Proterozoic Orogenic Event in Central Inner Mongolia1
Authors: Xishan Liu , Wei Jin , Shuxun Li
Published: August 2010

Abstract According to the kinds of feldspar and rock associations in the Al‐rich gneisses, the low‐pressure metamorphic crust of the Early Proterozoic granulite facies in central Inner Mongolia can be divided into southern and northern belts which are composed of six rock associations. They represent the relevant rock sequences of the layered metamorphic rock series formed under specific metamorphic temperature and pressure conditions as well as tectonic environments. Mineral inclusions and reaction texture have recorded that the medium‐temperature high‐pressure mineral assemblages are replaced by the high‐temperature low‐pressure mineral assemblages, thus, giving rise to: garnet+quartz? hypersthene+plagioclase; kyanite? sillimanite and garnet+ kyanite / sillimanite+quartz? cordierite. The deformation fabrics of the rocks, the change of mineral assemblages and the PTt path of metamorphism indicate that the contempranceous high‐temperature normal‐slip ductile shearing is the main cause of the formation of the low‐pressure metamorphic crust of granulite facies. In the orogenic event, the co‐action of thrusting and extension resulted in the change of a medium‐temperature high‐pressure metamorphic environment into the high‐temperature low‐pressure metamorphic conditions.
Negative Haloes and Geochemical Field Systems of Hydrothermal Deposits1
Authors: Kejian Ji , Liben Wang , Fengxiang Lu , Wuyi Wang , Jianhua Zhang
Published: August 2010

Abstract Primary haloes of hydrothermal deposits were previously considered as positive haloes. Although it has been recently suggested that primary haloes incude positive and negative ones, almost all the research work on primary haloes has still focused on positive haloes for various reasons. In order to understand the source of ore substances a number of large hydrothermal deposits related to magmatism including porphyry, skarn and vein type deposits have been studied. It has been found that negative haloes exist on the peripheries of positive haloes of a mineral deposit. On the basis of the study the authors propose the concept of the geochemical field system of ore‐forming elements of hydrothermal deposits, i. e., with the orebody as the centre outwards there occur the mineralized field, positive halo field, depleted field and background field successively.
The Formation and Evolution of the Lujiang—Zongyang Volcano—Structural Depression in Anhui and Its Relation to Mineralization
Authors: Qijiang Ren , Dezi Wang , Zhaowen Xu , Huogen Dong , Longquan Pan , Rongyong Yang , Changquan Fang , Jin'an Hu
Published: August 2010

Abstract The Lujiang—Zongyang volcano—structural depression resulted from the combined action of tectonism and volcanism. Its evolution progressed through five stages from 190 to 105 Ma B.P., during which nine types of metal and pyrite deposits were formed. These deposits show obvious regularities in the temporal—spatial distribution and have certain genetic relation, forming a minerogenetic series related to shoshonite within or around the volcano—structural depression on the basement that sank for a long period of time. This paper suggests a four—dimensional model of the formation and evolution of a typical volcano—structural depression and its related mineralizalion in a transition belt from the active margins to the inner part of a plate under alternating shear—compressive and shear—extensional stress conditions, but predominantly shear—extensional stress conditions.
Growth Dynamics of the Middle Devonian Jukoupu Bioherm, Xinshao, Hunan
Authors: Enpu Gong
Published: August 2010

Abstract The growth process, palaeoecological features and the function of organisms in reef‐building of the Jukoupu bioherm in Hunan are discussed in detail. The bioherm is divided into 10 micro facies. Organisms are very abundant in the reef. Thirty‐two genera belonging to 7 phyla have been recognized. They make up 5 communities composed mainly of stromatopoids, corals and algae, each of which has its own salient ecological features. An analysis of all communities shows that the organic functions are very complex. The same organisms may possess diverse functions simultaneously as the reef growth enters the late stage. The growth process of the reef may involve five stages: (l) biostrome stage, (2) stabilization stage, (3) frame‐type reef‐building stage, (4) binding and covering‐type reef‐building stage, and (5) baffle‐type reef‐building stage.
The PTst Evolution of Metamorphism and Development Mechanism of the Thermal ‐ Structural ‐ Gneiss Domes in the Chinese Altaides1
Authors: Yuxun Zhuang
Published: August 2010

Abstract A series of thermal‐structural‐gneiss domes (briefly TSG domes) are developed in the Chinese Altaides. Sericite‐chlorite zone, biotite zone, garnet zone, staurolite zone, kyanite (andalusite) zone, sillimanite ‐ cordierite (sillimanite ‐ garnet) zone, migmatite zone and migmatic granite ‐ gneiss field are developed from the low‐grade metamorphic area to the centre of the TSG domes. The succession of the formation and evolution of the progressive metamorphic zone, migmatite zone and migmatic granite‐gneiss corresponds to the spatial sequence from the outer part to the centre of the TSG domes. The peak temperature of the metamorphism and granitization increases progressively from 400 °C to 800 °C while the pressure decreases progressively from 1.05 GPa to 0.10 GPa from the biotite zone to the migmatic granite‐gneiss field. The metamorphism of the orogenic belt may be described by the pressure‐temperature‐space‐time model (PTst). In the main episode of orogeny, the deep heat flow and structural flow upsurged along a series of the centres of the regional thermodynamic anomalies, giving rise to the progressive metamorphism, granitization, and the differential uplift and the formation of TSG domes.
Structural Styles of the Longmenshan Thrust Belt and Evolution of the Foreland Basin in Western Sichuan Province, China
Authors: Hefu Liu , Huishe Liang , Liguo Cai , Fei Shen
Published: August 2010

Abstract The Longmenshan thrust system consists of two major groups of structural styles according to the depth of their involvement: basement thrusts ‐ compressional fault blocks; fold ‐ thrust system in the cover. In cross ‐ section, the Longmenshan structural belt is divided into 5 zones. The propagation of the Longmenshan thrust system is piggy ‐ back due to pushing at the early stage and overstep due to gravity sliding at the late stage. Balanced cross ‐ sections and palinspastic reconstruction reveal that the total sliding displacement of the thrust system amounts to 120 km. The tectonic evolution of the Tethys domain in western Sichuan has experienced 5 stages: continental break ‐ up; ocean ‐ continent subduction; continent ‐ arc collision; orogenic thrusting; uplift of western Sichuan.
Tectonic Characteristics and Evolution of the Taiwan Strait
Authors: Tianjun Gao , Hui Huang
Published: August 2010

Abstract The Taiwan Strait is a part of the continental‐margin rift of eastern China, which can tectonically be divided into the Taiwan Strait basin, southwestern Taiwan basin and Penhu‐Beigang uplift. The basins are structurally semi‐graban down‐faulted ones in character. The Cretaceous‐Cenozoic sedimentary strata in the basins have a maximum thickness of over 10,000 m. The formation and development of the Taiwan Strait rift were not only affected by both the East China Sea basin and South China Sea basin but also closely related to the Central Range collision orogen of Taiwan. In the Cenozoic, the Taiwan Strait area experienced, under the influence of a multiple of tectonic mechanisms, three stages of evolution: poly‐centre downfaulting, downwarping‐faulting and foreland basin formation. The depositional centres of the basins migrated from west to east during the Tertiary, resulting in the thinning of the Palaeogene strata from west to east but that of the Neogene in the reverse direction. All this determined the geological conditions for the oil‐gas generation in the Taiwan Strait.
The Songpan‐Garzê Massif: Its Relation to the QinlingFold Belt and Yangtze Platform and Developmental History1
Authors: Fengqing Yang , Hongfu Yin , Hengshu Yang , Xulong Lai
Published: August 2010

Abstract Whether there existed the Songpan‐Garzê massif is a controversial problem. This paper expounds and proves that the old basement of the massif is represented by the pre‐Sinian granitic rock series. This massif and the South Qinling fold belt might both be a part of the old Yangtze platform. Rifting generated by the Caledonian orogeny in the terminal Early Palaeozoic caused the massif to be disintegrated from the northwestern part of the Yangtze platform. This disintegration, however, was not thorough, and the rift troughs were later gradually closed and filled up. The Emei taphrogeny that was initiated in the Early Permian Maokou'an Stage involved a second disintegration of this massif from the Yangtze platform. The rift line largely goes along the Muli‐Pingwu line. This rifting belongs to synchronous extensional rifting at peripheries of the Yangtze platform and in its interior, showing that the posterior, lateral and interior extension resulting from rapid northward shift of the Yangtze platform led to isolation of this massif together with South Qinling from their adjacent areas. During the Ladinian Stage, the Songpan‐Garzê massif and southern Qinling sank strongly en masse. This subsidence continued till the end of the Late Triassic when the late Indosinian movement caused the sea trough to be closed and Songpan‐Garzê and southern Qinling to be folded and uplifted and become mountains.
Sedimentary Features of Shallow Ancient River Channels on the Northern Shelf of the South China Sea1
Authors: Yangqi Kou , Deli Du
Published: August 2010

Abstract Quaternary buried ancient river channels are widespread in the shallow‐level sediments of the northern shelf of the South China Sea. The sedimentary sequence mainly of fluvial deposits comprise an important component part of the low‐stand system tract and transgressive system tract in the study region. The plannar variation and spatial association of the sedimentary features such as incised valley fillings, deltaic foreset wedges and block slides of shelf‐marginal fans reflect the palaeogeographic environment during the fall of the regional sea level in the northern part of the South China Sea. Based on the high‐resolution seismic reflection data and gelogical data from boreholes, the present paper makes an integrated interpretation of the Quaternary ancient river channels in the shallow sediments of the study area, studies the sedimentary features of the ancient channels such as their spatial distribution, seismic facies reflection indicators, sedimentary facies and sand‐body types, and discusses their formational setting and evolutionary model, with the main purpose to render a service to the hydrocarbon resources exploration and development and marine engineering in the northern shelf of the South China Sea.
Deep Structures in China and Its Adjacent Areas: Plate Tectonics and Its Metallogenic Significance
Authors: Shengzao Chen
Published: August 2010

Abstract This paper proposes a new tectonic pattern of the deep‐seated structures in China and its adjacent areas (including the T‐A‐B system of the Ryukyu Islands). This is based on studies of the gravity field and gravity inversion coupled with the summation of the most recent achievements in geophysical studies. From a plate‐tectonic point of view, the metallogenic characteristics and their indications at depth, as well as relevant geophysical‐geological characteristics of four tectonic environments of the Chinese continent are analysed, and a classification of composite metallogenic provinces and belts and prediction of metallogenic prospects are made. The author extends the Kunlun‐Qilian‐Qinling tectonic belt to the T‐A‐B system of the Ryukyu Islands through the NW deep boundary of the Hangzhou Bay, and also proposes the following basic views: the migration and superposition of tectonic environments led to the formation of a composite metallogenic system; the change in the tectonic environment resulted in the superposition of various types of mineral deposits; seismic activities and metallogeny are mutually inducing factors. These views will be helpful to a discussion on the tectonic environments and metallogenic regularities.
Similarities Between Granites on the East and West Coasts of the Pacific Ocean
Authors: Liankui Wang , Shaoli Zhang , Wenxin Xu , Yuelong Liang , Gaoqiang Deng , Liankun Sha
Published: August 2010

Abstract: The traditional idea proposes that granites on the east and west coasts of the Pacific Ocean are different. According to field investigations of the geology of the western United States coupled with the authors' long‐term studies on granites in South China, granites both in eastern China and in the western United States are similar.
Biomarkers (Alkanes) of the Xuanlong ‐ Type Iron Deposits
Authors: Zhili Liu , Xuexian Liu , Pengfu Li , Rulin Du
Published: August 2010

Abstract The authors studied the biomarkers (alkanes) of eight iron ore samples from Nianpanshan and Dabaodui of Pangjiabao and Longguan, Xuanhua, Hebei. These samples have higher nC15 ‐ nC20 contents, with main peaks at nC16, nC17 and nC18, and contain abundant pristane and phytane. These results indicate that iron stromatolite and iron oncolites in orebodies are sedimentary structures of algal origin. Sedimentary iron accumulation mainly results from activity of blue algae. This study provides new valuable evidence for the origin of Xuanlong ‐ type iron deposits.
The Dabieshan Coesite‐bearing Eclogite Terrain—A Late Archaean Ultra ‐ high‐ Pressure Metamorphic Belt
Authors: Ronglong Cao , Shouhua Zhu
Published: August 2010

Abstract A U ‐Pb zircon age of 2774±24 Ma for eclogite from the Bixiling rock body of Anhui Province, central China, indicates that the Dabieshan coesite‐bearing eclogite was probably formed in the Late Archaean. A phengite Ar‐Ar isochron age of 662±13 Ma for the eclogite confines also an upper limit age of its subsequent retrograde metamorphism in the Precambrian. The results of isotopic dating for such type of eclogite coincide with the geological features of its restricted occurrence within the Archaean metamaorphic terrain composed of the Dabie Group. It is believed that the Dabieshan coesite‐bearing eclogite terrain might be a Late Archaean ultra‐high‐pressure metamorphic belt. The Dabie Mountains area was the eastward extension of the southern Qinling structural belt during the Triassic. Both the Dabie Group and the coesite‐bearing eclogite host,ed therein underwent a late‐stage dynamic metamorphic event. The present authors have obtained a muscovite Ar‐Ar isochron age of 192.6± 2.8 Ma from plagioclase gneiss and a hornblende Ar‐Ar plateau age of 230.7±4.6 Ma for the low amphibolite in eclogite respectively, which represent the Indosinian reworking ages of the original metamorphic rocks of the Dabie Group gneiss and coesite‐bearing eclogite.
Late Precambrian Scissors—Type Opening—Closing Tectonics and Its Dynamics in South China
Authors: Zhigang Xu
Published: August 2010

Abstract In this paper the author first reviews 6 major advances in the study of Precambrian geology and tectonics of South China during the last decade, and then proposes the following new model of Late Precambrian scissors‐type opening‐closing tectonic evolution in the region. (1) Besides the Middle‐Late Proterozoic low‐grade metamorphic basement, there existed a Late Archaean‐Early Proterozoic medium— to high—garde metamorphic basement in South China; both of them formed the united Yangtze‐Cathaysia (craton) at the end of the Early Proterozoic, with the Jiangxi—Anhui—Zhejiang palaeogulf extending into the inland and the Jiangxi—Anhui—Jiangsu Peninsula lying on the northern side of the palaeogulf. (2) From the Middle Proterozoic, the present Guangxi—Guizhou—Hunan area in the western‐central oldland was subjected to extensional rifting and became a rift trough, thus resulting in counterclockwise rotation of the “Cathaysian block” and clockwise rotation of the “Yangtze block” ; moreover, the southward compression of the Dabie‐Jiaonan block which split from the southern margin of the North China plate and was accreted to the northern margin of the Jiangxi—Anhui—Jiangsu Peninsula led to the scissors‐type closing of the Jiangxi—Anhui— Zhejiang palaeogulf during the Middle‐early Late Proterozoic, which further influenced the Early Palaeozoic tectonic evolution of the region.
The Arcuate Nappe Structure on the Northern Margin of the Wuliang Moutnains in Western Yunnan
Authors: Shujing Li , Yehua Shan
Published: August 2010

Abstract The arcuate nappe structure on the north edge of the Wuliang Mountains in western Yunnan Province is a complex nappe structural system with multiple superimposed structures. The autochthonous system is a WNW—trending arcuate fold belt consisting of the Jurassic and Cretaceous and the allochthonous system is mainly composed of Upper Triassic rocks. Generally, the nappe structure moved from south to north, with the hanging wall thrusting in a WNW direction for a distance of over 10 km. The deep nappe structural system was formed at depths of about 5–10 km in an environment not exceeding the greenschist facies. It occurred in the Oligocene (about 40‐20 Ma).
The Thermal History of the Huangmeijian Granite Intrusion in Anhiii and Its Relation to Mineralization: Isotopic Evidence
Authors: Yongfei Zheng , Bin Fu , Bing Gong
Published: August 2010

Abstract Whole—rock Rb—Sr, zircon U—Pb and hornblende, biotite and K—feldspar K—Ar ages are used to reconstruct the cooling history of the Huangmeijian intrusion in the Anqing—Lujiang quartz—syenite belt in Anhui. Oxygen isotope geothermometry of mineral pairs demonstrates that diffusion is a dominant factor controlling the closure of isotopic systems. Assuming the cooling of the intrusion is synchronous with a dicrease in local geothermal gradients, an emplacement depth of about 8 km and the magma crystallization temperature of 800 ± 50°C are estimated. The Huangmeijian intrusion experienced a rapid cooling process and uplifted after its emplacement and crystallization at 133 Ma B.P. with a cooling rate of 34.5°C / Ma and an uplifting rate of 0.35 mm/ a. The intrusion was rising until it rested at a depth of 3 km at a temperature of 300 ± 50°C about 14 Ma later. Then the intrusion was in slow cooling and uplifting with a cooling rate of 4.4°C / Ma and an uplifting rate of 0.04 mm/ a.

U—Pb dating of pitchblende is done for the hydrothermal uranium deposit formed in the contact zone of the Huangmeijian intrusion. The result shows that the mineralization age is close to the closing time of the K—Ar system in biotite. The fluid inclusion thermometry indicates that the mineralization temperature is in agreement with the closure temperature of the biotite K—Ar system. This suggests a close relationship between the slow cooling of the intrusion and the hydrothermal uranium mineralization process.
Chronostratigraphy and Stratigraphic Classification of the Cretaceous of the Songliao Basin
Authors: Pujun Wang , Xiaodi Du , Jun Wang , Dongpo Wang
Published: August 2010

Abstract Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonic scattering—settlement separation—K—Ar dilution technique. The apparent age of black mudstone is 123 Ma for the Quantou Formation, 111.9—89.0 Ma for the Qingshankou Formation and 77.6—76.8 Ma for the upper part of the Nenjiang Formation. The Rb—Sr isochrone age of the muddy limestone—mudstone sequence of the lower part of the Nenjiang Formation is 81 Ma and that of the muddy evaporite of the middle part of the Quantou Formation is 122.2 Ma. On the basis of the above isotopic ages, the authors propose a modified scheme of stratigraphic classification of the Cretaceous of the Songliao basin.
Simulation of the Subsidence and Deposition Processes of the Foreland Basin in the Southwestern Margin of Ordos
Authors: Shaofeng Liu , Sitian Li , Xinguo Zhuang , Yangquan Jiao , Zongsheng Lu
Published: August 2010

Abstract Characteristics of deformation in the thrust belt and sequence stratigraphie framework in the foreland basin, structural features of the basin margin, and the episodic thrusting are studied in this paper by combining the eastern Qilian thrust belt and the Late Triassic foreland basin on the southwestern margin of Ordos. On this basis, a geological model and a mechanical model of coupling mechanism were established for the pair of thrust belt and foreland basin, and the subsidence and deposition process of the foreland basin were simulated on given parameters.
Unconventional Geochemical Exploration for Gold Deposits
Authors: Xueqiu Wang , Xuejin Xie
Published: August 2010

Abstract Conventional geochemical exploration for gold deposits has not always been very satisfactory, especially for buried and blind ones. New considerations and methodology in sampling, analysis and interpretation have been developed in China during the past decade. Important considerations for unconventional gold exploration in this paper are that (1) gold is active in surface environments; (2) gold occurs not only as discrete grains, but also as ultrafine particles (submicron–to nanometer–sized particles of gold) and other complex forms; (3) regional low anomalies and superimposed anomalies over buried gold deposits are produced by ultrafine gold grains and other complex forms of gold. The methodology based on these considerations has been developed both in regional and in local geochemical exploration for gold. Examples of the preliminary application of these methods in two areas covered by transported overburden are given.
Palaeomagnetic Study of Permian Strata at the Yuzhou–Dafengkou Section, Henan
Authors: Hong Zhu , Guanxiu Yang , Axing Sheng
Published: August 2010

Abstract In western Henan, Late Palaeozoic coal measures are completely developed and well exposed. A great deal of research work on biostratigraphy was done by predecessors. After systematic palaeomagnetic studies, we have confirmed the existence of the Permian Kiaman reversed polarity epoch in the study region. Its palaeolatitude varied from 11.2° N(P1) to 15.6° N(P2). This provides important evidence for the view that this region was situated in a low latitude climatic zone in this period and gradually moved northwards from the tropic rain forest climate area to the tropic arid‐humid seasonal climate area during this stage.
Late Carboniferous–Early Permian Volcanic Event Deposits and Stratigraphie Correlation in Shandong Province and Its Adjacent Regions
Authors: Rong Zhong , Shanping Sun , Zeming Fu
Published: August 2010

AbstractDeposits of 10 volcanic events of 6 stages have been discovered by the authors after detailed field and lab studies of the Benxi and Taiyuan Formations in Shandong Province and its adjacent regions. They show certain temporal–spatial distribution characteristics. Volcanic fragments were probably derived from two different volcanic sources north and south of the North China Platform, while the magma of the two volcanic sources was probably derived from the lower crust. A new stratigraphie correlation scheme is put forward for the Benxi and Taiyuan Formations in this region on the basis of previous biostratigraphic work with the regionally widespread volcanic event layers as the marker bed for the isochronous stratigraphie correlation on a super–regional scale and in conjunction with the maximum transgressive event layers.
Carex yandangshanica sp. nov. (Cyperaceae; C. sect. Rhomboidales) from Zhejiang, China
Authors: Jin Xiao‐Feng , Zheng Chao‐Zong
Published: August 2010

Carex yandangshanica C. Z. Zheng & X. F. Jin, a new species of Carex sect. Rhomboidales Kükenth. from Zhejiang, China, is described and illustrated. The new species is similar to C. thibetica Franch. and C. brevicuspis C. B. Clarke, but differs from the former by having trabeculate leaves, pistillate spikes with 6–10 staminate flowers or without staminate flower at the apex, and achenes at apex contracted into a slightly curved beak, and from the latter by having lateral culms, trabeculate leaves, and elliptic, rubiginous and awned pistillate scales. SEM microphotographs of perigynia and achenes are provided for the new species and related taxa.
Persistence ofMycobacterium bovisBacillus Calmette‐Guérin in White‐Tailed Deer (Odocoileus Virginianus) after Oral or Parenteral Vaccination
Authors: Palmer M. V. , Thacker T. C. , Waters W. R. , Robbe‐Austerman S. , Lebepe‐Mazur S. M. , Harris N. B.
Published: August 2010

Mycobacterium bovisis the cause of tuberculosis in cattle and a serious zoonotic pathogen, most commonly contracted through consumption of unpasteurized dairy products. To control this zoonosis, many countries have developed bovine tuberculosis eradication programmes. Although relatively successful, efforts are hindered in many regions by spillover from wildlife reservoirs ofM. bovisto cattle. Such is the case in the United States where spillover ofM. bovisfrom free‐ranging white‐tailed deer to cattle occurs. One approach to control such inter‐species transmission is vaccination of wildlife. The live, attenuated human vaccineM. bovisBacillus Calmette‐Guérin (BCG) has been shown to reduce disease severity in white‐tailed deer; however, vaccine persistence within tissues has also been noted. Consumption of venison containing BCG by hunters may present a public health concern as BCG exposure, although unlikely to cause disease, could cause false positive tuberculin skin test results. To examine BCG persistence further, 42 white‐tailed deer were vaccinated orally or subcutaneously (SC) with BCG Danish. Three deer from each group were killed and examined at periods ranging from 2 weeks to 11 months after vaccination. BCG was recovered from orally vaccinated deer as late as 3 months after vaccination, while BCG persisted in SC vaccinated deer for as long as 9 months. At no time was BCG isolated from meat; however, prolonged persistence was seen in lymphoid organs. Although vaccine persistence was noted, especially in SC vaccinated deer, the distribution of culture‐positive tissues makes human exposure through consumption unlikely.
EFFECTS OF INDIVIDUAL HETEROGENEITY IN ESTIMATING THE PERSISTENCE OF SMALL POPULATIONS
Authors: CONNER MARY M. , WHITE GARY C.
Published: August 2010

ABSTRACT. Population viability models are commonly used to estimate the probability of persistence of small, threatened, or endangered populations. Demographic, temporal, spatial, and individual heterogeneity are important factors affecting the probability of persistence of small populations. Because stochastic process are intractable analytically (Lud‐wig [1996]), computer simulation models are often used for estimating population viability via numerical techniques. Although demographic, spatial, and temporal stochasticity have been incorporated into some population viability models, individual heterogeneity has not been included. In this paper we include individual heterogeneity in a simulation model and examine probabilities of population persistence at different levels of heterogeneity and population size. Individual heterogeneity may increase the probability of persistence of small populations. The mechanism for the extension in persistence may be explained by natural selection. Genotypes persisting through a decline may be those that survive better under the conditions causing the decline. These individuals that survive and reproduce in the face of adverse conditions may extend the probability that a small population persists.
AN INDIVIDUAL‐BASED FISHERY MODEL AND ASSESSING FISHERY STABILITY
Authors: HELU S. LANGITOTO , ANDERSON JAMES J. , SAMPSON DAVID B.
Published: August 2010

ABSTRACT. The stability of a fishery system was investigated using two forms of a stochastic computer simulation model that was individually based in terms of the fishing boats. Fish catch was partitioned among boats according to two catch processes: an unranked process in which all boats had equal ability to catch fish and a ranked catch model in which a boat's ability to catch fish depended on its wealth. Stock size, total catch, fleet size and individual boat wealth were modeled over a series of years. In the unranked catch model the fish stock size and fleet size were significantly more variable than in the ranked catch model.
HARVEST PLANNING UNDER UNCERTAIN EXTINCTION TIME
Authors: CAI DEQIN
Published: August 2010

ABSTRACT. Harvesting a targeted commercial species results in impacts on an endangered species which may have no direct market value but may need protection as mandated by environmental laws. A vigorous harvest path might drive the endangered species to extinction. This paper studies harvest planning when the endangered species is subject to an uncertain extinction time. It is shown that the optimal static harvest level under certainty can be used as an upper bound for the entire dynamic harvest time path under uncertainty. The paper also develops an explicit upper bound for the entire harvest path under uncertain extinction time of the endangered species. It is demonstrated that an increase in the hazard rate of the endangered species will shift down the upper bound for the entire harvest path, whereas an increase in the growth rate of the commercial species will shift up the upper bound for the entire harvest path.
COEXISTENCE OR EXCLUSION IN A COMPETITIVE COMMON‐POOL FISHERY: A REVISIONIST VIEW
Authors: McKELVEY ROBERT
Published: August 2010

ABSTRACT. One of the earliest applications of game theory to renewable resource modeling was Colin Clark's analysis, in 1980, of the competitive exploitation of a common‐pool resource. His model described the dynamics of a single Gordon‐Schaeffer fish stock, being harvested non‐cooperatively by two or more independently managed fleets. He showed that aggressive harvesting by all fleets (a Nash equilibrium) would lead to stock drawdown to a level which would successively eliminate all of the less efficient harvesters. Furthermore, when the fleets were closely matched, the survivor(s) of this aggressive competition would be forced, by the threat of competitors' reentry, to hold the stock in its severely degraded state, and hence to harvest at only marginal profitability. This outcome has often been compared to the open access “tragedy of the commons.” and to the outcome of the well‐known “prisoners' dilemma” game.

In this article I will argue that, for closely matched fleets, a more likely outcome is that the fleets will tacitly agree, without overt communication, to focus simultaneously on a specific set of coordinated policies which will permit their continuing coexistence and profitable operation. This policy profile also forms a Nash equilibrium, one which is secured by the mutual ability of the fleets to quickly recognize and credibly punish any unilateral deviations from the anticipated actions. Thus the dynamic harvesting game more nearly resembles the repeated prisoners' dilemma than it does the classical single stage version.
ON AXISYMMETRIC TRAVELING WAVES AND RADIAL SOLUTIONS OF SEMI‐LINEAR ELLIPTIC EQUATIONS
Authors: WITELSKI THOMAS P. , ONO KINYA , KAPER TASSO J.
Published: August 2010

ABSTRACT. Combining analytical techniques from perturbation methods and dynamical systems theory, we present an elementaryapproach to the detailed construction of axisymmetric diffusive interfaces in semi‐linear elliptic equations. Solutions of the resulting non‐autonomous radial differential equations can be expressed in terms of a slowlyvarying phase plane system. Special analytical results for the phase plane system are used to produce closed‐form solutions for the asymptotic forms of the curved front solutions. These axisym‐metric solutions are fundamental examples of more general curved fronts that arise in a wide variety of scientific fields, and we extensivelydiscuss a number of them, with a particular emphasis on connections to geometric models for the motion of interfaces. Related classical results for traveling waves in one‐dimensional problems are also reviewed briefly. Manyof the results contained in this article are known, and in presenting known results, it is intended that this article be expositoryin nature, providing elementarydemonstrations of some of the central dynamical phenomena and mathematical techniques. It is hoped that the article serves as one possible avenue of entree to the literature on radiallysymmetric solutions of semilinear elliptic problems, especiallyto those articles in which more advanced mathematical theoryis developed.
INTEGRATING MARINE PROTECTED AREAS INTO MODELS FOR FISHERY ASSESSMENT AND MANAGEMENT
Authors: HOLLAND DANIEL S.
Published: August 2010

ABSTRACT. Marine protected areas (MPAs) have been proposed as an insurance policy against fishery management failures and as an integral part of an optimal management system for some fisheries. However, an incorrectly designed MPA can increase the risk of depletion of some species, and can reduce the value of the system of fisheries it impacts. MPAs may alter structural processes that relate fishery outcomes to management variables and thereby compromise the models that are used to guide decisions. New models and data gathering programs are needed to use MPAs effectively. This paper discusses the motivations and methods for incorporating explicitly spatial dynamics of both fish and fishermen into fishery models so that they can be used to assess spatial policies such as MPAs. Some important characteristics and capabilities which these models should have are outlined, and a topical review of some relevant modeling methodologies is provided.
A MODEL FOR THE BIOECONOMIC EVALUATION OF MARINE PROTECTED AREA SIZE AND PLACEMENT IN THE NORTH SEA
Authors: BEATTIE ALASDAIR , SUMAILA USSIF RASHID , CHRISTENSEN VILLY , PAULY DANIEL
Published: August 2010

ABSTRACT. The use of marine protected areas (MPAs) as a basic management tool to limit exploitation rates in marine fisheries has been widely suggested. Models are important in predicting the consequences of management decisions and the design of monitoring programs in terms of policy goals. However, few tools are available that consider both multiple fleets and ecosystem scale dynamics. We use a new applied game theory tool, Ecoseed, that operates within a temporally and spatially explicit biomass dynamics model, Ecopath with Ecosim, to evaluate the efficacy of marine protected areas in the North Sea in both ecological and economic terms. The Ecoseed model builds MPAs based on the change in values of predicted economic rents of fisheries and the existence value of biomass pools in the ecosystem. We consider the market values of four fisheries operating in the North Sea: a trawl fishery, a gill net fishery, a seine fishery, and an industrial (reduction) fishery. We apply existence values, scaled such that their aggregate is similar to the total fishery value, to six biomass pools of concern: juvenile cod, haddock, whiting, saithe, seals, and the collective pool ‘Other predators’ that include marine mammals. Four policy options were considered: to maximize the rent only; to maximize the existence values only; to maximize the sum of the rent and existence values; and, finally, to maximize the sum of the rent and the existence values, but excluding only the trawl fleet from the MPA. The Ecoseed model suggests that policy goals that do not include ecological considerations can negatively impact the rents obtained by the different fishing sectors. The existence values will also be negatively impacted unless the MPA is very large. The Ecoseed model also suggests that policy goals based solely on existence values will negatively impact most fisheries. Under policy options that included ecological considerations, maximum benefits were derived from an MPA that covered 25–40% of the North Sea, placed along the southern and eastern coasts. Finally, the Ecoseed model suggests that an exclusion of the trawl fishery only from the MPA can provide small‐to‐substantial positive impacts to most species and fleets; this relative impact depends on level of interaction between the trawl fleet and the other fleets target species (e.g., through bycatch).
“NET INVESTMENT” AND SUSTAINABILITY
Authors: HARTWICK JOHN M.
Published: August 2010

ABSTRACT.We comment on research showing when constant consumption implies zero “net investment.” We also report on the use of ‘net investment “or” genuine savings “as an indicator of sustainability in abstract economies, with exhaustible resources and inherent nonconstant consumption paths. In particular, the use of the current percentage change in” net investment “is reported on.
NONRENEWABLE RESOURCE EXTRACTIONS WITH A POLLUTION SIDE EFFECT: A COMPARATIVE DYNAMIC ANALYSIS
Authors: LYON KENNETH S. , LEE DUG MAN
Published: August 2010

ABSTRACT. In this paper, we present a nonrenewable resource model including environmental pollution as a state variable. The model is analyzed to identify some of the characteristics of the optimal paths. In addition, we present a numerical example on the basis of the algebraic solutions of our qualitative model, and identify some of characteristics of the optimal time paths for two sets of social costs of the pollutant. These results are consistent with the proposition of the previous literature that levying the shadow cost of the pollution stock reduces the consumption of resource; hence, it slows the accumulation of the pollutant in the atmosphere. One quirk in the results, however, is that extractions will persist longer in the higher pollution cost scenario. The costate variable for the resource stock is decomposed into a scarcity effect and a cost effect; and the costate variable for the pollution stock is decomposed into an undesirable abundance effect and a cost effect. Both of these, however, are cost effects.
PARTICIPATION IN INTERNATIONAL ENVIRONMENTAL AGREEMENTS: THE ROLE OF TIMING AND REGULATION
Authors: FINUS MICHAEL , RUNDSHAGEN BIANCA
Published: August 2010

ABSTRACT.We analyze the formation of self‐enforcing international environmental agreements under the assumption that countries announce their participation either simultaneously or sequentially. It is shown that a sequential formation process opens up possibilities for strategic behavior of countries that may lead to inferior outcomes in terms of global abatement and welfare. We then analyze whether and under which conditions a regulator like an international organization, even without enforcement power, can improve upon globally suboptimal outcomes through coordination and moderation, given that recommendations must be Pareto‐improving to all parties.
MARINE RESERVES AS A MEASURE TO CONTROL BYCATCH PROBLEMS: THE IMPORTANCE OF MULTISPECIES INTERACTIONS
Authors: REITHE SIV
Published: August 2010

ABSTRACT. This paper explores the effects of using marine reserves as a measure to control bycatch that is of no commercial value, under different assumptions regarding the ecological interactions between targeted species and that taken as bycatch. Three cases are examined: (1) no ecological interactions between the two species, (2) targeted and bycatch species exist in a predator‐prey relationship and (3) species compete. Targeted species is assumed to consist of two sub‐populations that are discretely distributed in space, but linked through density dependent migration while bycatch species is assumed to consist of one uniformly distributed stock only. In each case the equilibrium stock levels of targeted and by‐catch species, effort and harvest are numerically calculated and compared, assuming pure open access and open access in combination with a reserve. It is of special interest to identify circumstances that allows for a win‐win situation, that is, both harvest of the targeted species and biomass of the bycatch species increase. It is shown that the ecological interactions between the two species influence the possibility of actually protecting the bycatch species through the use of a reserve, the possibility a win‐win situation, and the issue of what patch to close.
REBUILDING THE EASTERN BALTIC COD STOCK UNDER ENVIRONMENTAL CHANGE–A PRELIMINARY APPROACH USING STOCK, ENVIRONMENTAL, AND MANAGEMENT CONSTRAINTS
Authors: RÖCKMANN CHRISTINE , SCHNEIDER UWE A. , JOHN MICHAEL A. ST. , TOL RICHARD S.J.
Published: August 2010

ABSTRACT. . The population dynamics of the Eastern Baltic cod (Gadus morhua callarias L.), unlike many other stocks, shows a strong dependency on environmental conditions. To test the implications of different management policies on the stock and the fishery in a system of global environmental change, we apply a spatially disaggregated, discrete time, age‐structured model of the Eastern Baltic cod stock in 50 year simulation analyses. The simulation provides an analysis of stock, yield, and revenue development under various management policies and environmental scenarios. The policy analysis, focusing on different regulations of fishing mortality, is embedded into three environmental scenarios, assuming low, medium, or high climate and environmental change. The environmental assumptions are based on simulation results from a coupled atmosphere‐ocean regional climate model, which project salinity in the Baltic Sea to decrease by 7–47% in the period 2071–2100 relative to the reference period 1961 1990. Our simulation results show that a significant reduction in fishing mortality is necessary for achieving high long‐term economic yields. Moreover, under the environmental scenarios presented, a stock collapse cannot be prevented. It can, however, be postponed by the establishment of a marine reserve in ICES subdivision 25.
PERSISTENCE AND STABILITY IN ARATIO‐DEPENDENT PREDATOR‐PREY SYSTEM WITH DELAY AND HARVESTING
Authors: MAITI ALAKES , PATRA BIBEK , SAMANTA G.P.
Published: August 2010

ABSTRACT. . This paper aims to study the effect of time‐delay and combined harvesting on a Michaelis‐Menten type ratio‐dependent predator‐prey system. Dynamical behaviors such as persistence, stability, bifurcation, et cetera, are studied critically. Computer simulations are carried out to illustrate our analytical findings.