Geological Journal of China Universities

The energy prospect of China and frontiers of energy science and technology

Jia Cheng-Zao

2011, 17(2): 151-160.

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Exploitation of energy resources is the base for the economic society,s orderly development of our nation. From the analysisof domestic and overseas energy consumption structures, we found that coal consumption still takes large proportion in the national primary energy consumption structure. The national energy consumption structure forecast of 2030 shows that the drop in coal consumption is limited, nuclear energy, hydro-electric, and other new energy proportion will increase slightly. The paper, based on our national energy consumption structure, analyzes the national energy resources status and prospect, summarizes the frontiers of energy science and technology, and raises major technological problems of all energy resources fields, to accelerate the exploit ation of national energy resources.

Methods in studying petroleum accumulation systems in a superimposed basin: A case study of petroleum reserviors in the central Junggar basin

JIN Zhi-Jun

2011, 17(2): 161-169.

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The basic method in studying petroleum accumulation system in superimposed basins was demonstrated by a case
investigation in petroleum reserviors of the central Junggar Basin. The method can be summarized into two points. The first is
that the study is focused on petroleum reserviors. The second is that both organic and inorganic geochemical methods are used.
The case study in the central Junggar Basin shows that the area has at least two petroleum accumulation systems according to
the organic (biomarker in particular) studies, i.e., the Permian system in the eastern area to the Penyijingxi sag, and the Permian
and Jurassic system in the middle-eastern Mosuowan area. The study using inorganic geochemical method on reservoir diagenetic
calcite shows that the area has two additional petroleum accumulation systems, i.e., the Permian and Jurassic system in the
surrounding area of the Dongdaohaizi sag and the Permian system in the Shidong area. Moreover, the potential of retaining oil and
gas for each petroleum accumulation system was assessed to provide information for the exploration. Therefore, it is concluded
that the research method of petroleum accumulation system can help to improve the guidance on petroleum exploration, and the
organic and inorganic geochemical methods are complementary to each other. In particular, the new application of the inorganic
geochemical method is a supplement to and improvement for the previously and commonly used organic geochemical method, and
thus deserves to be studied further.

Basin types and distribution of the global giant oil and gas fields

Jia Dong, WU Long, YAN Bin, LI Hai-Bin, LI Yi-Quan, WANG Mao-Mao

2011, 17(2): 170-184.

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After summarizing previous research material of global giant oil and gas fields, the USGS data, and typical proto-type
basinal classification schemes, we classify the world’s 877 giant oil and gas fields and 153 main basins in which they are located.
In this paper, we present four maps and eight statistical histograms showing distributions of giant oil and gas fields and basins
based on different basinal classification schemes. Basin types and distribution of global giant oil and gas fields are identified, and
then the effects of different proto-type basin categories on the distribution of giant oil and gas fields are discussed. At the same
time, considering the complex tectonic evolution of basins as well as their association with hydrocarbon accumulation, we attempt
to classify superimposed basins according to their tectonic transformation or inheritance characteristics. Our results indicate that
basins with positive inversion features are optimum for the formation of giant oil and gas fields; successor rift basins and successor
foreland basins are less prominent, leaving negative inversion basin type to the least option.

Tectonic control on the hydrocarbon accumulation and prospect for large oil-gas field exploration in the southern Junggar basin

GUO Shao-Jie, TUN Chao-Dong, ZHANG Zhi-Cheng, CHEN Wei

2011, 17(2): 185-195.

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A series of thrust-fold belts were formed in the southern Junggar foreland basin during the Cenozoic. This paper
provides regional structural analyses of the thrust fold belts based on the growth strata, interpretation of seismic profiles, and
balanced cross-sections, together with available magnetostratigraphic results. Our analyses show that three paralleled rows of
anticlinal belts have been developed sequentially from the south to the north since ~7 Ma for the southern, ~2 Ma for the middle,
and ~1 Ma for the northern anticlinal belt, respectively. The systemic studies of the sedimentary sequences show that the source
rocks, reservoirs, seal rocks, and traps between the northern and southem margins of the Tian Shan are similar and there are three
petroleum systems (or plays) in the southern Junggar Basin. The reason why there has been no discovery large oil-gas field of so far
in the southern Junggar may be mainly due to the very late deformation and the existence of two detachment layers, i. e., the upper
detachment layer of the Ahjihaihe Formation (E2-3a) and the lower detachment layer of the middle Jurassic coal beds (J2x). This
paper proposes that the lower play, i.e., the Upper Jurassic reservoirs sealed by the Lower Cretaceous, is favorable for forming
large-scale oil-gas field and should be potential targets for future exploration.

The Geochemical Model of Petroleum, Natural Gas and Coal Multi-resource System

YAO Su-Peng, HU Wen-Xuan, JIAO Kun

2011, 17(2): 196-205.

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Through diagenesis, catagenesis and metagenesis, biological sources form petroleum, natural gas, and coal. These
processes are controlled by organic facies. Integrating sedimentology, organic petrology, and organic geochemistry, organic
facies is the most effective method to evaluate the petroleum, natural gas, and coal productivity potential of a certain basin. By
comprehensively analyzing the geochemical condition for petroleum, natural gas, and coal productivity, this paper proposes
the four end models based on maceral analysis to characterize organic facies and evaluate the petroleum, natural gas, and coal
productivity potential. With the method, Mesozoic strata of the Ordos basin and late Permian Wujiaping age strata of the Southeast
China are depicted as upper woody plants facies (A), lower woody plants facies (B), lower woody plants-exinite facies (C), shallow
water woody plants-algae facies (D), deep water herb-algae facies (E), and aquatic algae facies (F). Typical oil source rock and
humic coal are respectively formed in aquatic algal facies and upper woody facies. Upper woody facies and aquatic algal facies
are the main types of petroleum, natural gas and coal rich basin such as Ordos basin, but other transitional facies are found in
Mesozoic strata of the Ordos basin and Late Permian Wujiaping Age strata of the Southeast China which extend the genesis
theory of petroleum, gas and coal and multienergy exploration. By utilizing multistatistic analysis the authors develop an approach
to numerical representation of organic facies, build up the organic facies type index model which computes the model value of
contribution of organic facies to the genesis of petroleum, gas and coal and provide the basic method for geochemical quantitative

modeling of combustible organic mineral concentration.

Source Rock Features and Resource Potential of the Lower Cretaceous Strata in Coastal Southeast China

HU Guan, HU Wen-Xuan, Cao-Jian, TAO Su-Peng, XIE Xiao-Min, GAO Yu-Qiao

2011, 17(2): 206-219.

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By detailed field survey and organic geochemical analyses including organic matter abundance, type, and maturity of
the Lower Cretaceous strata in the coastal Southeast China, the source rock features of the strata were obtained. These features
allow a discussion on the hydrocarbon resource potential of the strata. The results demonstrate that there are in general two sets
of argillaceous hydrocarbon source sequences, i.e., the early Lower Cretaceous represented by the black mudstone of the Bantou
Formation in Fujian Province and the late Lower Cretaceous represented by the black mudstone or calcareous mudstones of the
Guantou Formation in Zhejiang Province. The organic matter abundance of the sources reached the moderate to good quality by
the hydrocarbon source rock standards, and the average TOC values and the chloroform bitumen “A” of the early stage sources
are high. The type of organic matter is mainly Type III, Types II and I can also be found and generally the types of late stage
sources are better than those of early stage sources. The thermal maturity of most samples is high to over mature, and organic
matter that was not significantly affected by volcanism is still in maturing stage. Thus, a relatively comprehensive hydrocarbon
resource evaluation indicates that the favorable regions are the northern Guangdong Province for the early Lower Cretaceous, andthe coastal region of Zhejiang Province and the western Fujian Province for the late Lower Cretaceous. These results may provide
new petroleum targets for oil-gas exploration in Southeast China.

Provenance Analysis of the Upper Triassic Flysch in Renbu Area, Southern Tibet

XU Wen-Li, LI Xiang-Hui, WANG Yin, ZENG Qiang-Gao, SUN Yong, NI Ma-Ci-Ren

2011, 17(2): 220-230.

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The sandstone clastic composition, paleocurrent, trace element and rare earth clement are combined to analyze the
provenance of the Upper Triassic Langjiexue Group and the Nieru Formation in Renbu area, southern Tibet. Results of the clastic
composition and geochemistry indicate that most of the clastic materials were derived from the recycled orogenic belt; Some of
them were from the mixed area before the orogeny; Few was from the continental basement and recorded continental margin arc
process prior to the orogeny. It is verified that parent rocks came from the recycled sediments of the orogen and post-Archean.
Paleocurrent measurement shows that the Langjiexue Group and the Nieru Formation were probably sourced from the North. The
former was from the northeast, but the latter was from the northwest. The latter is closer to the source region than the former. These
are consistent with the present distribution of strata. These results suggest that the upper Triassic flysch were probably sourced
from the north or even the Lhasa Block

Analysis of the Percolation Characteristics and Their Influence Factors on the Chang-8 Sandstone Reservoir in Jiyuan Area

YANG Yan-Fang, LUO Jing-Lan, YANG Jin-Long, LIU Xiao-Hong

2011, 17(2): 231-239.

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The Chang-8 Unit of the Yanchang Formation is a major reservoir in Jiyuan area, Ordos Basin. However, the reservoir
shows strong heterogeneity and oil production varies from well to well dramatically. In this paper, samples from 4 dr lling wells
were selected to conduct relative permeability sensitivity test so that the percolation characteristics and their influence factors
can be studied during the reservoir water-flooding process. Twenty casting thin sections were observed carefully, and the image
analysis of grain size and the analysis of pore-throat were carried out. Other tests were also done including capillary pressure
measurement, scanning electron microscope (SEM), X-ray diffraction and sensitivity analysis of clay minerals in the sandstones,
and the oil-water displacement experiment. The purpose of the work is to analyze micro-pore structures of the reservoir, clay
minerals, and the impact of diagenesis on relative permeability curve. Results show that the permeability curve of the reservoir in
the study area can be further divided into two types: the up-concaved and linear percolation curves. The up-concaved curve of the
corresponding reservoir belongs to the distributary channel microfacies with a high content of skeleton minerals, coarse grain size,abundant primary intergranular pores and large-diameter dissolution pore and good connectivity between pores. Mineral grain
contacts mainly occur as point to point and point to line, and the throat is coarse and long. The porosity and permeability of the
reservoir are high, and the fluid percolation is good. In addition, as to reservoirs with micro-cracks, proper water—flooding rate
can improve the efficiency of oil displacement. Because of the strong heterogeneity and high content of sensitive clay-minerals
of the reservoir, pressure should be increased gradually to raise the water-flooding pressure to eventually solve the problem of
clogging of pores by clay mineral. This research is important for understanding of reservoir percolation characteristics in the initial
stage of exploitation and is useful to enhance oil recovery

Cenozoic Tectonic Evolution of the East Java Basin, Indonesia

YANG Fu-Zhong, LUO Liang, Jia Dong, ZHU Hou-Qi, WU Long, LI Xia

2011, 17(2): 240-248.

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The East Java Basin is one of the most important oil and gas bearing basins in Indonesia. Its Cenozoic tectonic
evolution can be summarized as two rifting phases and two compressional events. The Eocene back-arc rifting basin resulted
from the northward subduction of the Indo-Australian plate under Sundaland. The subduction changed its direction to NE-SW
in the Oligocene, which induced the second phase of E-W extension and rifting. The Roo Rise ocean plateau, south of East Java,
collided with Sundaland at about 15 Ma, which resulted in the formation of major type of oil traps and positive inversion structures
in the basin. Part of the Australian proximal continental slope collided with the Banda Volcanic Arc at about 3.5-2 Ma and caused
the second phase of compressional deformation in the East Java Basin.

Geochemical Characteristics and Genesis of Crude Oils of Carboniferous and Triassic in Tahe Oil field of Tarim Basin

ZHENG Chao-Yang, LIU Yi-Qun, DUAN Yi, XU Wen-Xiu, FAN Ting-Ting, ZHANG Xue-Jun

2011, 17(2): 249-259.

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Because Tahe oil field is the largest marine carbonate rock oil field of the Tarim Basin, its genesis is of great interest.
By means of to the high-resolution GC-MS analysis of the oil samples from Carboniferous and Triassic Tahe oil field, this paper
studies biomarkers and discuss their genesis. The Pr/Ph, Pr/nC17 and Ph/nC18 data indicated that oil formed from sapropel
organic matters of reducing environment. Abundance of gammacerane C30⁺ hopane indicates that the oils formed from saltwater
environment. The abundance of C27 sterane, tricyclic terpane, tetracyclic terpane, and higher tricyclic terpane vs hopane
parameters show that original source materials are homonemeaes. Rearranged sterane/sterane, Ts/(Ts+Tm), and C29ββ/(ββ+αα)
are 0.24~0.40，0.28~0.50 and 0.56~0.63，respectively. All of these show that the maturity of the oil is high. The occurrence of
25-norhopane indicates that the oil experienced some degree of biodegradation. Comparison of oil and source rock suggests that
the oils of the main source rock came from the middle-upper Ordovician source rocks.

Quality of Reservoir Sandstones of Funing Formation in Yaotan Area from Jinhu Depression, Subei Basin, and Its Influencing Factors

ZHANG Ni, LIN Chun-Ming, YU Hao, YAO Yu-Lai, ZHOU Jian

2011, 17(2): 260-270.

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Reservoir sandstones of the Paleogene Funing Formation in Yaotan Area of Jinhu Depression mainly consist of lithic
arkose and arkose, with medium compositional maturity and median-high textural maturity. The Funing Formation reservoir
sandstones in Yaotan area are in the A stage of epigenesis, the main diagenesis of which includes compaction, cementation,
dissolution, and replacement. Diagenesis and tectonic movement influence the reservoir physical properties together, especially
affect the porosity and permeability of the reservoir in the study area. Compaction and cementation rapidly decrease the porosity
and permeability of the reservoir as well as the whole reservoir quality, while dissolution can improve the reservoir quality and
cause the development of secondary pores. Compaction in the reservoir of the study area mostly show as brittle fractures of rigid
particles, compressional deformation of plastic particles, rigid particles embedding into plastic particles, linear and concave-
convex contacts between particles, and the obvious directional alignment of detrital grains. Dissolution mainly present as the
dissolution of carbonate minerals, with the sements between detrital grains mostly being authigenic caly minerals, carbonate
minerals and authigenic quartz. The replacement in the study area mainly show as the replacement between the carbonate cements
and quartz, the feldspars and lithic debris, or inside the carbonate cements. The tectonic movement can partly improve reservoir physical properties in the study area.

Structural Anaysis of Binxian-Wangfu Sag in Songliao Basin

CHENG San-You, LIU Shao-Feng, SU San

2011, 17(2): 271-280.

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By means of two dimensional structure-stratigraphy interpretation of several seismic profiles, cross-section balancing,
and calculation of extension amount and extension rates, the paper investigated developing process of the Binxian-Wangfu sag
and analyzed the structural features and forming mechanism of the basin. The results show that Binxian-Wangfu sag was in the
initial stage of rifting in the Huoshiling Formation, Shahezi Formation and Yingchengzi Formation, and the fault depression was
mainly controlled by normal faults before the deposition of the Denglouku Formation. The sag onlaps to the Tangfangzhen uplift,
and was also controlled to some extent by normal faulting within the basin during the deposition. The sag completely turned into
depression and exhibited regional subsidence after the deposition of the Denglouku Formation, and the subsidence center was not
obviously corresponding to the early fault depression, and the subsidence of the Binxian-Wangfu sag was not controlled by the
early fault depression. During the Quantou Formation period, especially the third segment and the Qingshankou Formation period
the sag mainly showed depressional subsidence; The general structure of the basin was clearly marked by faults in the lower
section and onlap in the upper section. The basin formation was associated with the the NS-trending dextral transtension.

Research on Faults and Structures of Hulin Basin in Heilongjiang Province by Gravity Gradient Tensor

GAO Li-Kun, JIANG Fu-Yu, HUANG Lin-Yun

2011, 17(2): 281-286.

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The full gravity gradient tensor was calculated from gravity anomaly data of Hulin Basin with fast Fourier transform.
Based on zero values of Vxx and Vyy components indicating boundaries of sources and their orientations approximately along x
or y axes, Vzz indicating the location and extent of anomalies, Vzx, Vzy and Vxy highlighting structure of NS, EW and NE (NW),
a comprehensive analysis was conducted on the characteristics of Hulin Basin gravity and its gradient tensor. We deduced that
there are NE-NW-NEE-and EW- and NS-trending faults in the study area, five of which were described. Based on the synthetic
characteristics of gravity anomalies and their tensor, and fault distribution, Hulin Basin consists of three uplifts and two depressions,
corresponding to Yinchun uplift, Hulin River depression, central Hulin uplift, Donglinzi depression and Xingkai lake uplift.

Establishment and 3-D Visualization of Deep Structures in Foreland Thrust Belts: Taking the Jinfosi Thrust Belt in the Southern Margin of Jiuquan Basin as an Example

ZHU Min, CHEN Han-Lin, CHENG Xiao-Gan

2011, 17(2): 287-296.

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Jinfosi Pluton is seismically highly reflective medium and it has been difficult to obtain velocity data of the pluton
directly. The deep structures of Jinfosi thrust belt revealed by time-domain and depth-domain seismic data show significant
difference. We used the velocity data that were derived in laboratory under high temperatures and pressures simulating conditions
at depth to quautify the relationship between velocity and depth underground. This allows time-depth conversion for the 2-D
seismic data of the Jinfosi pluton and comparison of the deep structures of Jinfosi thrust belt revealed by the time-domain and
depth-domain seismic data. Based on the new depth data and interpretation, GOCAD software was employed to establish a 3-D
geological model, which allowed further discussion of the deep structures. The model shows that the Mesozoic-Cenozoic rocks form
a deeply buried monocline which dips SW and structural highs are relatively deeply buried with dips diminishing toward the two
limbs.

A Review on Mixed Rocks of Terrigenous Clastics and Carbonates and Their Petroleum-Gas Geological Significance

FENG Jin-Lai, HU Kai, CAO Jian, CHEN Yan, WANG Long-Gang, ZHANG Ying, WANG Mu, ZHAO Jian

2011, 17(2): 297-307.

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The present progress in research on mixed rock of terrigenous clastics and carbonates is reviewed in this paper, mainly
including classification, terminology, depositional environment, depositional modes and petroleum-gas geological significance.
It is proposed by a comprehensive analysis that the depositional facies favorable for the mixed deposition mainly cover coastal
and shallow-lake faicies, following by shallow-sea shelf, shore-shallow lacustrine and delta facies. The study on the depositional
environment implies that the factors controlling the development of coastal mixed-rocks include tidal effect, relatively strong
hydrodynamic condition and a shallow sea environment favorable for the living of lower organisms. In contrast, with respect to the
shore-shallow lacustrine rocks, the factors are frequent lake-level and climate changes. Consequently, a deep discussion on the
depositional micro-facies and associated environmental factors may be an effective way to improve and better the classification
and terminology of the mixed rocks. Furthermore, a synthetic depositional model for the marine and lacustrine environment is
suggested based on above-mentioned analyses, combined with case studies in Paleogene and Neogene middle-deep mixed rocks in
the northwestern Qaidam Basin. In addition, the shore-shallow sea and lake areas of mixed deposition can form high-quality targets of

reservoir and source rocks, based on factual research data on source and reservoir sequences associated with mixed rocks.

Characteristics and Mechanics of Cenozoic Salt-Related Structures in Kuqa Foreland Basins: Insights from Physical Modeling and Discussion

YIN Hong-Wei, WANG Zhe, WANG Xin, WU Zhen-Yun

2011, 17(2): 308-317.

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Salt layer has a significant influence on the structural deformation and evolution of Kuqa foreland basin. Structural
styles are quite different in the strata beneath and above salt. Strata above salt are mainly deformed by broad folding, while strata
beneath salt are mostly deformed by closely-spaced thrusts. Based on scaled physical experiments, we investigate the deformation
pattern and mechanics of Kuqa salt-related structures. Modeling results show that Kuqa salt-related structures are primarily
controlled by regional compression and growth sedimentation. Salt structures near the back end, such as Kelasu fold belt, are
controlled by regional compression, and salt structures near the front end, such as Qiulitake fold belt, have a significant influence
from the heavy growth sedimentation in the nearby Baicheng syncline.

Salt Structures in the Eastern Margin of Precaspian Basin and Their Relationship with Ural Orogeny

YANG Xiao-Qun, TANG Liang-Jie, ZHU Yong

2011, 17(2): 318-326.

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Based on the interpretation of seismic profiles, salt structures in the eastern margin of the Precaspian Basin and
their relationships with Ural orogeny were analyzed. The salt structures in this study area include salt diapirs, salt pillows, salt
rollers, salt welds, turtle structures and minibasins, which are featured by the zonation of deformation. There are zones of salt
weld, salt rollers, salt pillows, and salt diapirs from the east to the west. Salt controls the tectonic deformation of the suprasalt and
the subsalt, in which normal faults and thrust faults were developed, respectively. The cross sections show that salt experienced
two stages of deformation including the gravity spreading and differential loading halokinesis, and the salt structures had close
relationship with the Ural orogeny. Ural orogeny had reversed the strata in the eastern margin of the Precaspian basin, and exerted
strong influence on salt deposition and the subsquent deformation of salt driven by gravity spreading and differential loading.

Study on the Fluid Inclusions of Maoping Tungsten Deposit, Southern Jiangxi Province

HU Dong-Quan, HUA Ren-Min, LI Guang-Lai, WUI Xing-Lin, HUANG Xiao-E

2011, 17(2): 327-336.

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Maoping tungsten deposit is a large W-Sn-polymetallic deposit discovered recently in southern Jiangxi Province.
It comprises two types of ore-bodies, i.e. quartz-vein type and greisenized-granite type. This paper studies the fluid inclusions
in quartz and topaz occurring in wolframite-quartz-veins, which mainly includes microthermometry and Laser Raman analysis.
Besides, the homogenization temperatures of fluid inclusions in wolframite were determined under an infra-red microscope.
Results show that fluid inclusions in both quartz and topaz are mainly liquid-rich two-phase aqueous solution (H2O-NaCl), in
addition to small amount of CO2-bearing three-phase aqueous solution in quartz. The homogenization temperatures from quartz
show a wider range variations and can be divided into two main periods, indicating two stages of ore precipitation. The CO2-bearing
three-phase inclusions have homogenization temperatures similar to those of the higher temperature period of the above inclusions,
but lower salinities and different homogenizing ways. Fluid inclusions in wolframite have highest homogenization temperatures
and salinities, whereas those in topaz also show high homogenization temperatures and salinities, and narrow variation range. The
characteristics of homogenization temperatures and salinities from fluid inclusions in quartz reveal multiple-stages of ore-forming process and the complexity of fluid evolution. It is concluded from fluid inclusions that the early-stage boiling and late-stage
mixing are probably the major mechanism of formation of wolframite-quartz-vein type ore in the Maoping deposit

Genesis and Prospecting Significance of Lead-Zinc Ore Bodies in Jiama Mining Area, Tibet

ZHENG Wen-Bao, TANG Ju-Xing, LI Feng-Ji, YING Li-Juan, WANG Huan, TANG Xiao-Qian

2011, 17(2): 337-350.

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Jiama copper polymetallic deposit is one of the large deposits that gained prospecting breakthrough in recent years in
Gangdese metallogenic belt, Tibet. By comparing with typical SEDEX deposits, this article means to point out the genetic type
of Jiama deposit as porphyry-skarn type, related to porphyry metallogenesis. The porphyry system of Jiama hosts many different
mineralization types owing to different wall rocks, including porphyry Mo-Cu deposits centered in intrusions, skarns, hornfels,

and Au deposits in independent peripheral locations. The differences between Jiama and typical SEDEX deposits are as follows.
① Geologic features show that the magmatic hydrothermal solutions not only formed layered skarns in the space of K1 l and J3 d,
but also small-scale, lensing and cystiform skarns in the pelitic limestone interlayers of K1 l . There are no exhalative sedimentary
rocks in Jiama mining area, and the so-called exhalative sedimentary rocks in the previous papers, in fact, are skarnized hornfels.
The mineralization with an age of 14~16 Ma might be related to the delamination and large-scale crust stretching due to Gangdese
collision orogenesis in Miocene epoch, and the porphyry intrusion event in later period. The copper polymetallic deposit of skarn
has no double-layer structure, typical of SEDEX. The upper skarn with the wall rock roof has a gradual transition relationship.
Skarn with coarse grained texture is the result of minerals, self-growth because of long time magmatic supplies. ② Geochemical
characteristics. The combination of ore-forming elements is mainly of Cu, Mo, Au, Ag association, and in less amount Pb, Zn. Mn
contents in limestone of J3d show negative anomaly compared with the regional background. The Zn / (Pb+Zn) ratio in Jiama Pb-
Zn deposit mainly concentrates in two ranges of 0-0.1 and 0.2-0.45. Mineralization of the deposit presents a zoning Mo→Cu+Mo
→Cu→Pb+Zn. Isotopically, in contrast to SEDEX deposits, the δ 34S values of Jiama deposit are negative and concentrated, and its δ 30
Si values are positive. Besides, an ore-prospection model is set up in this article based on the magmatic-hydrothermal theory
of metallogenesis to search for the areas in Nyainqentanglha region with geological conditions similar to Jiama deposit, and to find
the Pb-Zn ores in shallow, peripheral parts of porphyry bodies and Cu-Mo-W ores in their deeper, central parts.

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