Table of Content

20 April 2010, Volume 24 Issue 2

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Water Resource and Environment

Study on Early Permian Flora and Palaeoecology in the Wuda Area of Inner Mongolia

SUN Ke-Qin

2010, 24(2):  195-204. 

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The fossil plants studied in this paper were collected from the Early Permian strata in the Wuda area of Inner Mongolia, China. This flora is composed of 20 species in 11 genera and they belong to Lycopsida, Sphenopsida, Noeggerathiales, Filices, Pteridospermopsida and Cycadopsida. The result shows that the flora contains many typical Cathaysian elements and endemic species and it is a typical Cathaysia flora. On the basis of the floral components, the geological age of the flora is equivalent to the Early Permian, corresponding approximately to Asselian, Sakmarian, Artinskian and Kungurian. Based on the studies of the flora, floral palaeoecology is studied in the paper and the Lepidodendron posthumiiParatingia datongensi community can be set up in the area. The plant community, which was the most abundant in the swamp and lowland environments during the Early Permian, was characterized by the largest number elements of ferns and pteridosperms. The plant community is preserved autochthonously and the life forms of vegetation can be reconstructed by means of fossil materials, including arbores, tree ferns, shrubs and herbs. The plant community indicated a warm and humid climatic condition in the area during the Early Permian.

Sporopollen Assemblages and Stratigraphical Significance of Paleogene Dongying Formation in Nanpu Sag, Eastern Hebei Province

ZHANG Yang-Fang, JIANG Jun-Wei

2010, 24(2):  205-213. 

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The palynological analysis of 124 samples in this paper was carried out from B13, B26, B28, G6, G7, G10, G20, G27 and G39 wells of Dongying Formation, Nanpu sag, eastern Hebei Province. According to the sporopollen contents, one assemblage has been proposed which was characterized by the predominance of Ulmipollenites undulosus, with high content of Pinaceae among gymnospermous pollens and abundant Ulmipollenites, Quercoidites, Juglanspollenites and Betulaceae among angiospermous pollens. Four including the two caeval subassemblages can be recognized as Ed₃, Ed₂ and Ed₁, namely, Ulmipollenites undulosusQuercoidites subassemblage, JuglanspollenitesTiliaepollenites subassemblage/PinaceaeChenopodipollis subassemblage and CedripitesPiceapollis subassemblage. Moreover, the detailed interpretation has been given on difference of the two coeval Ed₂ subassemblages. Sporopollen assemblages from Dongying Formation in Nanpu sag were compared carefully with those from other sags in Bohai Bay Basin and the results show that Nanpu sag sporopollen assemblages possess similar features with others, but with some small differences. The studied assemblage with high content Ulmipollenites undulosus may be assigned to Oligocene in age based on distribution of major Gymnospermous pollens, Angiospermous pollens and the first occurrence of a few Neogene pollens.

Evolution of Paleoenvironment since Late Pleistocene of SC1 Core in Chenghu Lake, Jiangsu Province

SHI Kai

2010, 24(2):  214-220. 

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Based on the analyses of grain size, magnetic susceptibility, sporopollen, foraminifera, lithology and AMS14C from SC1 core in Chenghu Lake, this paper discusses the evolutions of climate and paleoenvironment since Late Pleistocene.The records of sporopollen show that climate is accord with the worlds: warmwet during the Late Pleistocene, a cool and dry climate during the last glaciation, warmwet in the Early Holocene, a hotwet climate in the Middle Holocene, cooldry to warmmoist during the Late Holocene; Two marine invasion events are discovered, one is Gehu during Late Pleistocene and the other is Zhenjiang in the Middle Holocene.This district has undergone great palaeogeographic changes since Late Pleistocene: rivers in the Late Pleistocene, rivers and marshlands during the last glaciation, flood plainestuary during the Early Holocene, estuaryshallow marine in the Middle Holocene, lakes and marshlands during the Late Holocene.

SequenceStratigraphic Framework for the Ediacaran in the Southeastern Part of Guizhou Province

ZHANG Hai, GAN Feng-Wei, WEI Ning

2010, 24(2):  221-227. 

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Ediacaran system in Guizhou Province is made up of the Doushantuo Formation and the Dengying Formation, in which the Doushantuo Formation is mainly composed of siliceous rock, and the Dengying Formation is mainly marked by micritic dolomite. On the basis of sequencestratigraphic division for some typical sections, sequencestratigraphic framework for the Ediacaran system in the southeastern part of Guizhou Province can be established. The stratigraphic succession from the Doushantuo Formation to the Dengying Formation constitute an upward shoaling sedimentary succession, and this succession make up one secondorder sequence that can be further divided into 5 thirdorder sequence. Importantly, the similarity of succession of sedimentary facies between the secondorder and thirdorder sequences reflects the basic feature, i.e. “cycle within cycle”. Furthermore, an important phenomenon that dolomites in shallow platform do not change into limestone in deepwater basin within the Dengying Formation reflects an important sedimentary feature, i.e. this set of dolomits may be resulted from primary precipitation that is same as the formation of “cap dolomite” in the bottom of the Doushantuo Formation and may represent the continuation of “the extreme greenhouse effect” in the Late Precambrian.

Metallogenic Fluid Characteristic Study of the Fenghuangshan Cu Deposit at Tongling, Anhui Province

JI Hong-Ying, FEI Rong-Fu, WANG Yong-Lei, LI Jin-Wen

2010, 24(2):  228-236. 

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This study takes the Fenghuangshan copper deposit as an example to examine the metallogenic mechanism, the nature and origin of oreforming fluid using the characteristics of metallogenic fluid and C, D and O isotope analysis. The Fenghuangshan deposit contains garnet, quartz and calcite in which fluid inclusions were well developed. The fluid inclusion can be classified into V-L type, V-L+S type, V-L rich gas type, and V type. Most of the fluid inclusions in garnet, quartz and calcite are concentrated mainly in three zones and the temperatures and salinity ranges of fluid inclusions represent three different phases of oreforming fluid evolution, indicating that the fluid experienced a continuous process of evolution, which was well coupled with metallogenic phases of the Fenghuangshan deposit. Temperature decreasing and fluid boiling resulted in the discharge of a large amount of copper from Cubearing fluid. Furthermore, H and O isotopic analysis indicates that the oreforming fluid consists mainly of magmatic water, with minor meteoric water at the late stage of mineralization of the Fenghuangshan deposit.

Metallogenic Characteristics of Barite and Witherite of the Barium Metallogenic Belt in Southern Qinling Mountains

TUN Qing-Hua, LIU Jia-Jun, ZHANG Nai, LIU Zhen-Jiang

2010, 24(2):  237-244. 

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More than 70 witherite and barite deposits  (or points) are located in Southern Qinling Mountains, which is a unique large Ba metallogenic belt in the world. By microthermometry analysis, the peak of fluid inclusions homogeneous temperature has a increasing trend from barite to witherite. The δ³⁴S values of barite of the deposits are higher than those of the same period water of ocean basin (except one δ³⁴S value of barite of Wenyu deposit, which is close to those of the same period water of ocean basin),which shows that the ³⁴S enrichment in barite could be due to the reduction from germs to sulfate.Witherite deposits of Southern Qinling exist different ranges of δ¹³C and δ¹⁸O value, and C of witherite comes from reaction of organic matter.According to thermodynamics data, temperatue below 162.42 ℃ is favourable to forming barite ore;when temperature is over 162.42 ℃, and there is enough CO₃^2-  (from reaction of organic matter), it is favourable to forming witherite in sea water.In the late period of forming barite deposits,if Ba²⁺ appears deficient in hydrotherm, and  CO₃^2-  (from reaction of organic matter)is enough and temperature is over 16242 ℃ in sea water,CO₃^2- will metasomate the SO₄^2-  of barite to form metasomatic type witherite.

Study of Applying Factor Analysis Method to the Geochemical Division in Stream Sediments in the Chabaqi Area of Inner Mongolia

DAI Hui-Min, BAO Qiang-Zhong, GONG Chuan-Dong, YOU Hong-Liang, SUN Zhong-Ren, YAN Guo-Lei, JIN Xin

2010, 24(2):  245-251. 

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The authors analyzed the 1∶50,000 stream sediments data in the Chabaqi area of Inner Mongolia with the Rmode factor analysis method, and eight representative factors were extracted from the data. The geochemical divisions have a close relationship with the geological bodies by making a study of the factor score map, the geochemical division map and the geologic map. The element combination of arsenic, stibium, copper and zinc is mainly related to the Linxi Formation，and the distributions of division are in accordance with those of the Linxi Formation. The lead and zinc divisions are mainly distributed in the andesite and dacite of the Guanghua Formation,metamorphic rocks of the Laolongtou Formation, and tonalite of Early Jurassic，they are mainly distributed in the NE direction. Besides smaller divisions are distributed in the north of the study area, divisions of silver and tungsten are mainly distributed in the Late Jurassic adamellite of the south study area, and the distributions show that elements of silver and tungsten have closed relation to the granite body. A gold ore occurrence was found in the arsenic, stibium, copper and zinc divisions, and a leadzinc ore occurrence is located in the lead and zinc divisions during field practical investigation. By the study of geochemical division, we have known the geologicalgeochemical implications and their reciprocal relationships. The research method can provide some significant information for the geological survey.

Characteristics and Application of Compound Specific Isotope in Oil-source Identification for Oils in Dongying Depression, Bohai Bay Basin

LI Su-Mei, GUO Dong

2010, 24(2):  252-258. 

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Compound specific isotope analysis was performed to help to investigate the origin and source rocks for some oils with source rock still confusing. The Es₃ genetic affinity oil from lacustrine with freshwater is characterized by bimodal distribution with the mainpeak to be around nC₁₅ and nC₃₂, respectively and the forepeak particularly enriched in ¹³C. This kind of oil generally has a little heavier δ¹³C values relative to the other oils. The brackish Es₄ genetic affinity oil also shows a bimodal distribution, displaying a symmetrical “double peak” shape with the boundary consistently to be around nC23. It was observed that the Es₃ and Es₄ source rocks are plotted cluster with the Es₃ and Es₄ genetic affinity oils (based on biomarkers in previous studies) respectively, suggesting their good genetic relationship. The oils from subtle pools of Es₃^M in the Niuzhuang Sag have an intermediate δ¹³C values between the Es₃ and Es₄ genetic affinity oils and much more approaching the latter, suggesting oil mixing of the two types oil, which is consistent with the previous opinion about mixed-source oils of the Es₃^Mfrom the Es₃ and Es₄ intervals for the Niuzhuang oils based on biomarkers. It was observed that highwaxy oils from Kongdian Formation (Ek) in the Dingjiawozhi tectonic belt of the Niuzhuang South Slope have flat isotope distributions, which are plotted with the Ek source rock in the Niuzhuang Sag and Ek genetic affinity oils in the Huanghua Subbasin. It suggests a close genetic relationship between the Ek oil and the Ek source rock in the Dongying Depression. We conclude that maturity only has a minor effect on the isotope for the oil and source rocks in the Dongying Depression, and it is the organic input as well as paleoenvironment of the source rock which have an absolute controlling on the isotope after detailed oiloil and oil-source correlation. Therefore, compound specific isotope approach is an excellent tool for the oil-source rock correlation in the area studied, which can be a complementation for the previous studies based on biomarkers.

A Biodegradation Experiment of Crude Oils in Laboratory and Quantitative Evaluation

XIANG Ting-Sheng, HEI Hua-Li

2010, 24(2):  259-267. 

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In this study, effective hydrocarbon degrading mixed bacteria (I strain) has been obtained by screening, and three kinds of oil (Xi 5-P10, Sanyuanhou, G1131-262) from three different wells respectively in Daqing oilfield have been degraded by experiments with different time intervals. Then GC-MS analysis has been carried out on the oils. The change of the distribution of the saturated hydrocarbons and aromatic hydrocarbons of the oil is probed into by quantitative analysis. The results show that strain I is a kind of high-efficient hydrocarbon degrading bacteria; the degradation abilities to the three kinds of crude oil by the same type of bacteria are different significantly, so the field test of hydrocarbon contamination by bioremediation requires different high-efficiency biodegrading bacteria depending on the property of the oil; that not only the past conclusions of the biodegradation orders of saturated hydrocarbons and aromatics biodegradation are verified, but also some new views are put forward. Such as the degradation of hopanoid is after the rearrangement steranes, naphthalene start to degrading earlier than phenanthrene and trimethylnaphthalene earlier than tri-methyl phenanthrene, tri-methylnaphthalene and tetra-methylnaphthalene achieve a balance after the depth of biodegradable and degradation rate slow down after that. When hydrocarbon is degraded to a certain stage,  PAHs of stronger anti-biodegradation is enriched which will increase the toxicity to the environment, so PAH-degrading bacteria or naphthalene, phenanthrene-degrading bacteria or other special effect bacteria will be a key of environment bioremedation.

Evolution of the Sagaing Strikeslip Fault and Its Control of  Shwebo Basin Structural Evolution,Myanmar

XIE Nan, JIANG Ye, SHU Guang-Hui, YANG Song-Ling, LI Ai-Shan, Zhang-Ke

2010, 24(2):  268-272. 

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The formation and development of the Sagaing strip-slip fault can be classified into two main stages. The first stage is from Paleocene to Early Eocene, and oceanic plate subduction occurred along the west edge of the Burma plate. Paleocene oblique subduction has detached the Burma plate from the Eurasian plate, and the Sagaing fault began forming. The second stage is during Eocene, and the northeastern Indian and Burma plates collided, resulting in the coupling of these two plates and also accelerating the northward movement of the Burma plate along the Sagaing strip-slip.The dextral strike-slip displacement distance of Sagaing fault is up to 450 km. Controlled by the evolution of Sagaing fault, the Shwebo subbasin presents two stages of structural features. During Miocene, the Burma basin was in tensional stress, the Andaman Sea opened, back-arc spreading center drove to south because of the India coupling with western Myanmar. From Early Pliocene to Pleistocene, collision of the Burma plate and Himalayan resulted in southwest-northeast transpressional forces that produced reverse faults. Therefore,by squeezing and twist-compression of the Shwebo subbasin a series of reverse faults and “flower” structures are developed, and ultimately in south-north trend Sagaing dextral strike-slip compression stress and west-east trend transpressional environment formed.

The Appearance and Significance of Palaeo-Drainage Systems Connection in the Top of Lower-Middle Ordovician in Tahe Oilfield

CA Zhong-Xian, LIU Yong-Li, LIU Qun

2010, 24(2):  273-278. 

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 Karst fracture-vug systems of Lower-Middle Ordovician in Tahe oilfield, develop very well, during multi-stage tectonic movement and karstification, from Middle Caledonian to Hercynian. Except for the dissolubility of the rock, karstification mainly depends on the denudation and corrosiveness of karstic water, in course of supply-through flow-drainage. So, predicting the trace of karstic water is an important method. Based on 3D seismic data, applying third generation coherence technique, karst palaeo-drainage systems in the top of Lower-Middle Ordovician can be described, and below overlay area of Upper Ordovician, there are still many palaeodrainage systems, most of which are connected well with palaeo-drainage systems in lost area of Upper Ordovician. According to karst theory in modern times, we divide karstic series of strata, confirm the hydrogeologic condition, and analyse the forming and consuming course of karst palaeo-drainage systems in two stages, which can play an important role on recovering the environment of palaeokarst, dividing the stages of palaeokarst and revealing the rule of palaeokarst.

The Application of RMS Extracting Technology in Geologic Modeling on Carbonate Reservoir with Cavern

MO Fang, CUI Wen-Ban, LI Shi-Chao

2010, 24(2):  279-286. 

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Three-dimensional geological molding (3D-GM) is getting more and more important in the oil-gas field exploration. The utility of 3D-GM in the detrital reservoirs is mature and efficient; however, in the carbonate reservoirs, it still lies in the exploratory stage. With the developing of the geophysical technique and its extensive using in the research of petroleum geology, people become aware of the practicality of the seismic technology. In this article, authors use PETREL reservoir modeling software, adopting the RMS seismic attributes extraction technology as the core modeling method, to establish the distribution model of carbonate cavities. A contrast between the real and the predicted caves shows that 54 out of 72 predicted data inosculate the real ones. The coincidence rate is 75%. The model precisely reconstructs the Tahe-4 region^,s underground directional distribution and provides a valid reference for the subsequent exploration.

The Study on Ordovician Carbonate Reservoir Karst Cavern Fillings Characterization in Tahe Oilfield

XU Wei, CA Zhong-Xian, GU Zhen-Yuan, LIN Zhong-Min

2010, 24(2):  287-293. 

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The Ordovician carbonate fracture-cavern reservoir has been the most important oil and gas production interval in Tahe oilfield. Large numbers of karst caverns conduced by the paleo-karstification play an important role in the oil and gas storage. The karst caverns filled with sedimentary deposits are divided into four karst cavern filled facies, which are speleothem facies, transposition lithofacies, collapsebreccia facies, vadose filling facies, in 11 karst caverns filled wells. The transposition lithofacies is the karst cavern fillings at the early stage. When the corrosion of surface karst develops to a certain extent, the rocks break down to form the collapse-breccia facies, and later stages the vadose fillings is the interstitial matrix in collapse-breccia facies.  From the model of well Ta, the authors get a caverns filling order, which has the top cavern disturbed facies,middle collapse facies and the bottom marine influx filled facies. The trace element and rare earth element geochemistry characterization of cavern fillings proves the marine-meteoric water mixed karst, which will guide the production of the oilfield.

Microfacies and Diagenesis Analysis of Bioclastic Limestones of T₇⁴Sequence Boundary in Bachu Area, Tarim Basin

CHU An-Shen, HUANG Wen-Hui, XU Bing-Song, FAN Ta-Liang

2010, 24(2):  294-300. 

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The T₇⁴ boundary outcrop profile is located in the north-east Bachu County, Tarim Basin, which separate Upper Ordovician and MiddleLower Ordovician. The lithology of this boundary is bioclasts packstones and wackstones. Based on the microfacies analysis, the bioclasts rich in biospecies mainly consist of echinoids especially in crinoids and ostrocods. Other bioclasts include brachiopod, mollusc, trilobite, calcispher, dasycladus, serpulid, foraminifera, sponges and bryozoan. Analysed by microscopes, carbone-oxygen isotope and X-ray fluorescent analysis and so on, the results show that the strata of T₇⁴boundary formed in the warm and lower energy shelf facies and subsequently experienced burial compact diagensis, meteoric diagensis and weathering diagensis following the strata uplifting. The development of stylolite with good porosity and permeability is favour of fluids movement in the subsurface and is an important factor to the development of karst in Middle-Lower Ordovician.

Re-explanation for Deposition and Reservoir Characteristics of the First Member of Yaojia Formation in Talaha-Qijia Area of Songliao Basin

YANG Yu-Fang, ZHONG Jian-Hua, CI Wei-Liu, NI Liang-Tian, CHEN Zhi-Feng

2010, 24(2):  301-310. 

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By using the high-resolution sequence stratigraphy theory,through depositional dynamic analysis,the cores of 20 wells and 496 well logging data,Putaohua reservoir of the Talaha-Qijia area in Songliao Basin is divided as 1 long-term base level cycles,3 medium-term base level cycles,8 short-term base level cycles,proposed a new framework with the sedimentary structure lifting control the north and west of Putaohua reservoir. Fine study of sedimentary characteristics reveals that the most favorable facies sandbody is narrow submarine river sandbody, thin channel-mouth bar and sheet sanbody. In the northern half of the study area a large number of broad thick favorable submarine river sandbody is not oily but water-bearing zone.It is realized that sandbody development and distribution of lithologic reservoirs are controlled by a slope break. Area within slope break is the LST for the center of mass deposition, which is thick or thin layer of sandstone, and can form the stratigraphic overlapped traps. Area under the slope break is the delta front facies sandstone superimposed zone of LST and TST of 3 sequences with the development of thin sandstone and poor connectivity, and is a multi-layer lithologic trap development zone. Area above the slope break has a large number of plain and front facies thick channel sand body of TST. Its connectivity is good, so oil and gas are easily lost and difficult to form a lithologic trap.This area had become a large-scale water-bearing zone. All shows that “the slope break controls the distribution of stratum,facies,sands,traps and oil reservoirs” theory has once again been an excellent application and verification in the study area.

Inner Structure and Spatial Evolution of Complex Delta of the Second Member of Shahejie Formation of Paleogene in Qibei Sag， Bohai Bay Basin

LU Chao, JIAO Yang-Quan, TUN Li-Qun, LV Lin

2010, 24(2):  311-320. 

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Research on deltas in Qibei sag can be done on different scales.After the works of the application of seismic attributes, the tracing of seismic facies and the analysis of the sand distributed system,we find that the composite delta is divided into western part and migratory eastern part. The seismic facies present that there is a similar “s”-type foreset reflectance characteristics of the delta of the second member of Shahejie Fomation in Qibei sag, which is seismic reflection characteristics of lateral migration of delta.Based on the discovery of the phenomenon of lateral migration, we track the axes in seismic profiles in plane to determine the scope of the the migratory delta in plane of each period of time, finally acquire the area and evolution of the delta with all the periods of time,and find that in the lowstand systems tract of the second member of Shahejie Fomation the East Delta migrate eastwardly six times while in the highstand systems tract the East Delta migrate eastwardly four times.The West Delta continually deposits vertically. The existence of the phenomenon of lateral migration makes the East Delta has different heterogeneity characteristics from others, sandstone possess interaction of positive rhythm and counter-rhythm. Porosity which as a whole is relatively low with an average 14% in East Pelta, is lower than the average of  24.4% in the West Delta; the average sediment permeability of this type, which is 0.0172×10^-3 μm², is lower than that of the West Delta which is 0.0375 × 10^-3 μm²; content of carbonatite with an average of 13.5% in East Delta, is higher than that with the average of 9.6% in the West delta.

Source Provenance and Depositional Characteristics of the Upper Part of the Forth Member of Shahejie Formation in Binnan-Lijin Area, Dongying Depression

LIU Hui-Min

2010, 24(2):  321-328. 

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The provenance of the sandbodies of the upper part of the fourth member of the Shahejie Formation in Binnan-Lijin area of Dongying depression was studied by the methods of types and content of detrital grain and the distribution patterns of the ratio of characteristic elements.There were two provenance systems in the fourth member of the Shahejie Formation in Binnan-Lijin area, including Lijin provenance system from Chenjiazhuang uplift and Binnan provenance system from Binxian uplift. The detrital grain was fine and the sand with high quartz and high metamorphic lithic contents was the main clastic sedimentary in Binnan provenance system. The detrital grain was coarse and the sand with low quartz and high sedimentary lithic contents was the main clastic sedimentary in Lijin provenance system. The different provenance systems developed different sandbody types and depositional characteristics because of different mother rock properties, paleogeomorphic and tectonic evolution characteristics. The fan delta, braid delta and beach bar were the main sandbody types in Binnan provenance system. The nearshore subaqueous fan and turbidite fan were the main sandbody types in Lijin provenance system.

Major Evidence for Gas Hydrate Existence in the Qilian Permafrost, Qinghai

LU Zhen-Quan, ZHU You-Hai, ZHANG Yong-Qin, WEN Huai-Jun, Jia Zhi-Yao

2010, 24(2):  329-336. 

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Gas hydrate was discovered for the first time on the continent of China, namely in the Qilian Mountain permafrost of Qinghai Province in the winter of 2008 and the summer of 2009. In the field, white icelike gas hydrate and the burning phenomenon were directly observed. Its obvious relevant anomalies were also recorded. These anomalies include phenomena of strongly bubbling and water seeping on the fresh surface of gas hydrate bearing cores, a chain of bubbles coming from under water when gas hydrate bearing cores are submerged, extraordinary gases coming from the well when gas hydrate bearing layers are drilled through, a large amount of gases when gas hydrate bearing cores are extracted under airtight conditions, heavy hydrocarbon traces and residual cellular textures over the surface of gas hydrate bearing cores, concomitant rhombic autogenetic calcite crystals, relatively low temperature signals indicated by infrared camera, etc. Indoor Raman spectrometry excellently detected normal peaks of hydrate water and its caged hydrocarbons. Macroscopically gas hydrate bearing layers corresponded to high electrical resistivity and sonic velocity in the log profile. Generally gas hydrate and its related anomalies occurred either in the pore and fissure of fine sandstone or in the fissure of mudstone, oily shale, siltstone at the 130-400 m interval of the Qilian Mountain permafrost.

Characteristics of Pollution and Microscopic Morphology of Atmospheric Particulate Matter in Beijing during 2008 Olympics and Paralympics

SHAO Long-Yi, LIU Jun-Xia, SONG Xiao-Yan, NIU Hong-Ye, ZHANG Fang

2010, 24(2):  337-344. 

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In August and September of 2008 Beijing held the 29th Olympics and 13th Paralympics successfully. The atmospheric particulate matter was collected during this period on the campus of China University of Mining & Technology (Beijing) which is about 3 kilometers from central Olympic Stadium. The mass concentrations and morphological types of the airborne particles were investigated. The results showed that the mass concentrations of PM₁₀ and PM_2.5 during the Olympics were well below the national standard II (150 μg/m³) and USA-EPA daily mean standard (65 μg/m³)， respectively, with the 12-hour means ranging between 7.64 μg/m3 and 81.63 μg/m3 for PM₁₀ and between 1.91 μg/m³ and 54.59 μg/m³ for PM_2.5. The 12-hour concentrations of PM10 during Paralympics ranged between 33.83 μg/m³ and 106.36 μg/m³, which are higher than those during the Olympics but are still lower than the national standard II. Mass concentrations of PM_2.5 during the Paralympics samples ranged between 15.29 μg/m³ and 88.30 μg/m³, and the PM_2.5  levels during most days of Paralympics were relatively low, except 6th, 7th and 14th of September when the PM_2.5  level exceeded USA-EPA daily mean standard. The PM_2.5 /PM₁₀ ratios during the Olympics and Paralympics were in the range between 0.26 and 0.86, mostly higher than 0.5, demonstrating a predominance of the PM_2.5  in PM10. Compared with previous years, mass concentration of PM_2.5  and PM₁₀ are both in a decreasing trend. The microscopic morphologies and size distribution of particle samples were further examined by FESEM and Image Analysis. Spherical particulate, soot, irregular minerals and unknown fine particles were identified. The number-size distribution of these samples showed that the particles are mainly concentrated in the size range of  0.1-0.2 μm, in which the spherical particles are dominated. All data indicated that the pollution of the airborne particles in Beijing city during the Paralympics is more severe than that during the Olympics.

Study on Pollution Characteristics of PM25 in the Aerosol, Tracing and Tracking Atmospheric Particulates in Beijing City

CHEN Yuan, CEN Kuang, S.Norra , NSchleicher , YU Yang

2010, 24(2):  345-354. 

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This study focused on the pollution characteristics of fine particles in the aerosol in Beijing city, analyzed the correlation between variation of mass concentration and various kinds of natural factors. Tracing and tracking the particulates have been done with HYSPLIT model of the U.S. Air Resources Laboratory. What we do will provide important basic data for getting a correct understanding of pollution situation of PM_2.5in urban areas and give reference for future comparative research and development of corresponding pollution control measures. The research results are as follows: (1) the highest value of mass concentration of PM_2.5 appears in sand and dust weather in April; spring has the highest mass concentration in the four seasons due to sand and dust weather. (2) Mass concentration of PM_2.5shows strong but different correlations with the temperature in different seasons or different range of temperature; wind speed has a negative correlation with the concentration when it is below 10 km/h and positive correlation when above that.(3) Dust mainly comes from the northwest, northwest by north or west direction; outside sources are the Gobi or desert areas in Russia, Mongolia, Kazakhstan and other countries; sources inside China are mainly the Gobi or desert in west as well as a wide range of arid and semiarid areas in Inner Mongolia; after arriving in Beijing, dust moves to the east, northeast or southeast, entering into North Korea, South Korea, Japan, Russia and other neighboring countries.

Pollution Level and Source Analysis of Polybrominated Diphenyl  Ethers(PBDEs)from Atmospheric Matter PM_2.5 in Beijing

YANG Xue, LIU Da-Meng, SUN Jun-Ling

2010, 24(2):  355-361. 

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In January, September and October,2008, 9 PM_2.5 samples were collected concurrently at 5 contrasting sites. The mass concentrations of 14 Polybrominated Diphenyl Ethers (PBDEs) congeners were detected with isotope dilution and high resolution gas chromatography/high resolution mass spectrometry (HRGS/HRMS) based on US EPA-1614 method. The pollution level, spatial distribution and source of 14 PBDEs atmospheric matterPM_2.5  in Beijing were analyzed. The results show that the mass concentrations of PBDEs are in the range of 2.82~57.94 pg/m3 with mean value of 15.67 pg/m³, and the mass concentration of BDE-209 is in the range of 0.34~7.32 pg/m³. The mass concentration of PBDEs in PM_2.5  in winter is higher than that in autumn. Monomer distribution of PBDEs in PM_2.5 samples is different, and the mass concentrations of penta-BDE and hexa-BDE are higher than those of tetra-BDE and tri-BDE. The PBDEs pollution are generally from traffic, industrial fuel and fire retardant, the contribution to PBDEs pollution is fire retardant, industrial fuel and traffic in descending order.

The Variation of Evapotraspiration and the Impacts on It in the Source Region of the Yangtze River

PEI Chao-Zhong, QIAN Kai-Zhu, LV Jing-Jing, XIN Yuan-Hong

2010, 24(2):  362-368. 

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The source region of the Yangtze River has experienced ecohydrology deterioration in lastest 2 to 3 decades. To analyse the region hydrological variations, exploit Surface Energy Balance System (SEBS), based on NOAA remote sensing data, and the meteorological data provided by local meteorological stations, we calculated the annual evapotranspiration (ET) in the source region of the Yangtze River from 1991 to 2001. Employing linear regression method to count the evapotranspiration trends in every pixel, we analysed the interannual variation of evapotranspiration spatially. Using Geographic Information System, the impacts of temperature, surface land temperature, precipitation and NDVI (vegetation index) on evapotranspiration variation have been assessed. The results show that evapotraspiration increases at the speed of 6.8 mm/a. The rising temperatures with the Global Warming are the main factors to lead to the interannual evapotraspiration increasing in the lastest two decades. In space, evapotranspiration increases at the left bank of the Yangtze River, which is sunny aspect, while the evapotranspiration decreases at the right bank of the river, back sides of the mountains. Precipitation and vegetation coverage have a good positive correlation with evapotranspiration respectively.Evapotranspiration in the southeast of the region with large rainfall and relatively dense vegetation is larger than that in the northwest of the region with small rainfall and sparse vegetation. Findings of this study may be significant for finding out relationship between water resources and climate changes.

Hydrochemical Characteristics and Hydrogeochemical Modeling of Groundwater in the Jiaozuo Mining District

HUANG Peng-Hua, CHEN Jian-Sheng, NING Chao, HAN Su-Min

2010, 24(2):  369-376. 

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In order to study the chemical evolution mechanism of the underground water in the Jiaozuo mining district and ascertain the recharge sources of karst water to provide scientific evidence for the prevention of mine water bursting, water from the study areas is sampled. The piper diagram, lithology effects, the correlation matrices, TDS, and quantitative hydrogeochemical simulation technology are used to gain the hydrological geochemistry function in spatial distribution and evolution rules.  Mass balance reaction model of underground water is established to provide quantitative information of evolution mechanism about the chemical constituents of karst groundwater. It is discovered that the exchange of positive ions of Ca²⁺-Na ⁺、Mg ²⁺-Na ⁺ efflorescence and lioxiviation evaporation and concentration, non-congruent dissolution of dolomite are the major hydrological and chemical process to control the formation and the evolution of the underground water，which provides a theoretical basis to infer the recharging sources of groundwater in the mining district.

²¹⁰Pb and ¹³⁷Cs Dating and Modern Sedimentation Rate in the Wulungu Lake, Xinjiang

JIN Ai-Chun, JIANG Qing-Feng, CHEN Ye, ZHANG Guang-Sheng, ZHAO Yong-Jie

2010, 24(2):  377-382. 

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Using ²¹⁰Pb and ¹³⁷Cs dating methods, based on observation on profiles of two sediment core samples，the average deposition rate of the Wulungu lake in recent decades is determinated.  Sedimentation rates of  ²¹⁰Pb (CRS model) determination range from 0.018 to 0.071 g/(cm²·a) and sedimentation rates  of  ¹³⁷Cs determination  range from 0.034 to 0.060 g/(cm²·a). The results showed a relatively good agreement with each other. It is indicated that natural factors have much more influence than human activities on the sedimentation rate of Wulungu lake before 1960s. With the development of agriculture and implementation of water transfer project at the middle and lower reaches of Wulungu River, human activities gradually become the dominant factor in the evolution of lakes, thus affecting the sedimentation rate of Wulungu lake after 1960s.

Characteristics of Geophysical Anomalies of the Prospecting for Hulu Magmatic Cu-Ni Deposit in Hami of Xinjiang

SHAO Xing-Lai, XUE Chun-Ji, DAI De-Wen, YAN Yu-Tong

2010, 24(2):  383-391. 

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 Hulu magmatic Cu-Ni deposit in Hami of Xinjiang is located at the eastern Tudun-Huangshan-Jingerquan-Tulaergen mafic-ultramafic complex suite. The deposit with an outcrop of Upper Carboniferous Wutongyaozi formation is a typical mafic-ultramafic sulfide deposit. It is very helpful for the deposit exploration in the whole complex suite to study and summarize the characteristics of geophysical anomalies. According to the results from the 1∶5,000 ground magnetic survey and 1∶5,000 transient electromagnetic sounding profiling that we have obtained recently, and the IP that other researchers have already studied, it is revealed that the deposit was in the place with anomalies of high magnetism, high polarizability and low resistivity. The values of ΔT, ηa and ρa were above 500 nT, above 6% and below 200 Ω·m,respectively. These data were significant information for finding potential prospecting areas. Based on the drilling results, this paper also discussed the genesis of the anomalies and the relation between anomalies and deposit in the threedimensional space. Finally, it was found that much lower resistivity anomalies were not definitely caused by reactions of the deposit.

Analyzing Scale Characteristics of Random-Uniform Medium by Wavelet Transform

LI Can-Ping, LIU Xue-Wei, ZHAO Gui-Yan

2010, 24(2):  392-396. 

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To study scale characteristics of heterogeneities in complex heterogeneous medium, this paper constructed random and uniform media models. Scale characteristics of three kinds of seismic waves, namely direct wave, scattered wave and reflected wave, in random and uniform media were studied and analyzed by wavelet transform. The results showed that three kinds of seismic waves behaved different scale characteristics, and direct wave behaved large scale characteristic, and scattered wave was second, and reflected wave behaved small scale characteristic. With lateral autocorrelation length of model parameter becoming larger, optional scale of direct wave had a trend of decrease, and optional scale of scattered wave and reflected wave had a trend of increase. Therefore, the research of this paper offered a reference to analyze scale characteristics of heterogeneities and seismic wave in seismic section by wavelet transform.

TEM Modeling of a Long Conductive Line Resource

LIU Yu, LI Yun-Zhe, HUANG Zi-Ying

2010, 24(2):  397-402. 

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1.School of Geophysics and Information Technology，China University of Geosciences，Beijing100083，China；
2.Beifang Institute of China Ordnance Industrial Geotechnial Investigation & Design，Shijiazhuang, Hebei050011，China；
3.Institute of Geological Exploration，Hebei Geological Department，Shijiazhuang, Hebei050011，China

Study on the Eigenvector Combination Model of Mineralizing Alteration
Information Extraction Based on the ASTER Data -Taking the Area of Hongqi Mountain in Inner Mongolia as an Example

LIU Li, XIANG Ya-Li, LU Xue

2010, 24(2):  403-408. 

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The area of Hongqi Mountain in the Ejinaqi,Inner Mongolia,is abundant in mineral resources, but the work of mineral survey is still at a lower level, and the orebodies are scattered, which make the traditional methods of prospecting useless. In this study, ASTER (Advanced Spaceborne Thermal Emission and Reflection) data is used to extract the information of the alteration of rocks and minerals-Based on the method of the crosta, the combination model with selected eigenvectors of PCA is effectively done to extract the alteration information of the iron mineralization, kaolinization+sericitization  and chloritization. The result is validated by the known mineralization spots. This study shows that ASTER data has better capability for recognition of clay mineral.It also proves the feasibility of this method used for mineral resources searching by remote sensing at such regions.