Table of Content

20 October 2019, Volume 25 Issue 5

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Petrogenesis and Tectonic Implications of the Laohushan Quartz Diorite from the Eastern Part of North Qilian Orogen, NW China

ZHANG Hairui，ZHAO Jiaolong，YU Huiyang

2019, 25(5):  641. 

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This paper presents comprehensive zircon U-Pb ages and whole-rock geochemistry for the Laohushan quartz diorite in the
eastern segment of the North Qilian Orogen, with aims to elucidate their petrogenesis and constraints on the early Paleozoic tectonic
evolution of North Qilian Orogen. Zircon LA-ICP-MS U-Pb dating of the Laohushan quartz diorite yielded an age of 440 Ma. Rocks
from the Laohushan pluton show sub-alkaline and metaluminous signatures, relatively low CaO, MgO and Fe2O3T contents, agpaitic
index (AKI) values of less than 0.85, and aluminum saturation index (A/NKC) values of mostly less than 1.0. The Laohushan pluton can
thus be grouped into metaluminous calc-alkaline I-type granitoids. All of the rocks are also enriched in LREEs and LILEs (e.g., Rb, Cs,
Th and U) and depleted in HFSEs (e.g., Nb and Ta), similar to the geochemical characteristics of typical arc magma rocks. They have
homogeneous Sr and Nd isotopic compositions with (87Sr/86Sr)i values of 0.7058~0.7071 and εNd(t) values of -1.06~-0.31. Integrated
petrological, elemental, and isotopic compositions indicate that the Laohushan quartz diorites were generated by mixing of
mantle-derived material with crustal-derived magmas that were formed by dehydration melting of basaltic rocks from the lower crust. By
comprehensively synthesizing geochemical compositions and geological setting for magma rocks within the study region, we propose
that the northward subduction of back-arc basin induced by the subduction of the North Qilian oceanic plate and the subsequent
collision between the Qilian-Qaidam block and magma arc were major dynamic mechanisms responsible for the emplacement of the
Minleyaogou and Laohushan granitoids and the adakitic rocks within the Maozangsi-Laohushan granitoid belt.

New Insight into Petrogenesis and Tectonic Setting of the Rhyolite from the Lingshan Island in Qingdao Region, Shandong Province

ZHANG Shukai， MENG Yuanku， WANG Zeli

2019, 25(5):  654. 

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In this study, we conducted systematically zircon U-Pb dating of two representative rhyolite samples from the Lingshan
Island in Qingdao, Shangdong Province. The results show that the weighted ages of two rhyolite samples are ca. 123.1±1.9 Ma and 121.4±
1.4 Ma. These two ages are consistent within the uncertainty, representing the formation and crystallization age of the rhyolite.
Geochemically, the rhyolite samples show high contents of SiO2 and Na2O+K2O, while they are characterized by low contents of P2O5 TiO2
and CaO, as well as low Mg# values. In addition, the rhyolite samples are enriched in LILEs (Rb, Th and K) and LREEs, but depleted in
HFSEs (e.g. Nb, Ta, Ti and P). Rock assemblages, geochemical features, and low whole-rock Zr saturation temperatures indicate that the
rhyolites belong to highly-fractionated I-type rhyolite rather than A-type rhyolite in an extensional setting, and are products of
post-collisional magmatism. The zircon εHf(t) values range from -27.2 to -32.3, and the sencond stage model ages are between 2662 and
3167 Ma, indicating that the rhyolite was origanited from partial melting of ancient crust. The presence of Neoproterozoic inherited
zircons indicates that it was originated from partial melting of the Yangtze middle-crustal material. These results suggest that the
destruction of North China Craton (NCC) was the cause, leading to large-scale partial melting of the Yangtze crustal material. The
regional extensional tectonics related to the destruction of NCC provided emplacement space for the rhyolite in the last stage.

Characteristics and Genesis of Sinian Dengying Formation Dolomite in the Xichuan Area, Southwestern Henan Province

ZUO Pengfei，SUN Jiangtao，ZHENG Deshun，LIU Sicong

2019, 25(5):  670. 

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The late Precambrian dolomites are widely developed in the Yangtze Craton and its periphery areas in the Dengying
Formation. As the diagenetic assemblages and sedimentary sequences of the Dengying Formation in the northern Yangtze Craton are
quite different from those in the Yangtze Craton, it is critical to study the formation process and paleoclimatic implications of the
dolomites. Based on the field profile measurement, thin section observation, cathodoluminescence, and X-ray diffraction study of the
Dengying Formation in Xichuan area, the dolomite can be divided into four types, i.e., anhedral mud-powder crystalline dolomite,
euhedral-subhedral fine crystalline dolomite, subhedral-xenotropic fine-coarse crystalline dolomite, and saddle to karst breccia
dolomite. The anhedral mud-powder crystalline dolostone is the product of dolomitization related to high salinity seawater in the
penecontemporaneous stage. The euhedral-subhedral fine crystalline dolostone was deposited in the early diagenetic stage related to
shallow-buried dolomitization, which was caused by the infiltrating reflux of high salinity seawater. The subhedral-xenotropic
fine-coarse crystalline and saddle dolostone are the product of hydrothermal dolomitization or recrystallization of carbonate minerals in
the middle-deep burial environment in the late diagenetic period. The karst breccia dolomite is related to the dissolution-collapse of
early dolomite. Changes in diagenetic environment resulted in the development of different types of dolomites in the study area.

Sr Isotope Characteristics of Salt Rocks in Simao Basin, Southwestern Yunnan and Its Implications

FANG Lihua，XIA Zhiguang，LI Weiqiang，YIN Hongwei1， MIAO Zhongying

2019, 25(5):  679. 

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The Mesozoic-Cenozoic Simao Basin is an important salt-bearing basin in Southwestern Yunnan, Southwestern China.
There is controversy on the origin of the salts from the Simao Basin. In this paper, we analyzed the Sr isotope characteristics of the salt
in different salt-bearing zones from the Simao Basin, to shed insights into the source of the salts. Sr isotopic (87Sr/86Sr) ratios of drill core
samples in Mohei vary from 0.708598 to 0.709333, which are consistent with the 87Sr/86Sr ratio of the salt rocks (0.707504 to 0.711069)
reported from other parts of the Simao Basin. Such range of 87Sr/86Sr ratio is consistent with that of Mesozoic-Cenozoic seawater (i.e.,
0.7068-0.7092). Based on Sr isotope evidence, in combination with the geological evolution history of the basin, geochemical and
mineral characteristics, we propose that the Mesozoic-Cenozoic salt in the Simao Basin is mainly of marine origin, but a small
proportion of terrigenous materials were delivered to basins via rivers during the evaporite-forming events.

H-O, He-Ar and Sr-Nd-Pb Isotopic Constraints on the Sources of Ore-Forming Fluids and Ore-Forming Materials in the Xiadian Gold Deposit, Jiaodong

DU Foguang，JIANG Yaohui，QING Long，NI Chunyu

2019, 25(5):  686. 

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The Xiadian gold deposit is a large Jiaojia-type gold deposit in Jiaodong district. On the basis of detailed petrographic and
mineralogical studies, we carried out the H-O isotopes and the first He-Ar and Sr-Nd-Pb isotope tracing studies of the Xiadian gold
deposit, which furnish the new constrains on the source of ore-forming fluids and materials. H-O isotopes of fluid inclusions in quartz
（δDV-SMOW=-102.3‰~-93.9‰ ，δ18OH2O=-0.2‰~1.6‰）reveal that the ore-forming fluids is mainly composed of enriched mantlederivedfluidwithinvolvedalittlemeteoricwater.
He-Arisotopeofpyrite[3He/4/He=0.58×10−6~1.90×10−6(0.42~1.36Ra),40Ar/36Ar=724.7~
1358.4] also indicates that the ore-forming fluids are dominant by the enriched mantle-derived fluid. Nd-Pb isotopes of ore and altered
rocks are different either from those of the surrounding granites and the basement metamorphic rocks or from those of Mesozoic
asthenosphere-derived basalts. Instead, they are consistent with those of Mesozoic lithospheric mantle-derived lamprophyres in the
Jiaodong district. However, their initial 87Sr/86Sr ratios are higher than those of the lamprophyres and even higher than the surrounding
granites. The Sr-Nd-Pb isotopic characteristics indicate that the ore-forming fluids and ore-forming materials were derived from the
enriched lithospheric mantle with subsequent interacted with the basement metamorphic rocks during the ascending process.

Advances and Prospects in Geochemical Tracing for Shallow-Water Hydrothermal Activities

WANG Xiaoyuan，GUO Kun，ZENG Zhigang

2019, 25(5):  697. 

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The seafloor hydrothermal activity research has become a hot and popular field in marine geology in recent years. Compared
to the deep seafloor hydrothermal activity research that has drawn much attention, the shallow-water hydrothermal activity research is
still at an infancy stage. Because the shallow-water hydrothermal regions are often located at regions close to where human activities
take place, shallow water hydrothermal systems can affect human’s life. Shallow-water hydrothermal activity research is helpful to
understand the cyclic process of hydrothermal fluids, the origin of hydrothermal fluid, and related dynamic processes. This paper
presents recent adavnces in shallow-water hydrothermal activity research using geochemical tracers. In addition, we highlight major
scientific questions and suggest important future research directions, including the following three aspects: sources of shallow
hydrothermal fluids and gases; the relationship between shallow-water hydrothermal system model and structure environment; the
influence of shallow-water hydrothermal activity on human.

Oxygen Tolerance of Sulfate Reducing Bacteria in Fresh and Coastal Sea Waters under Enrichment Culture Conditions

CHEN Yawen，ZHANG Zhaohui

2019, 25(5):  705. 

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Sulfate-reducing bacteria (SRB) play an important role in the process of organic matter mineralization and formation of
biogenic pyrite in lake and coastal sea sediments. Understanding how SRB respond to dissolved oxygen contents (D.O.) in fresh and
coastal sea waters is essential to predict future evolution of mineralization under increased eutrophication and seasonal hypoxia. So far
most pure cultures of sulfate reducing bacteria have been conducted under strict hypoxic conditions, in which SRB would gradually
lose oxygen tolerance in the original habitat. In order to address how SRB respond to D.O. contents with co-existing bacteria, we
collected water samples along the D.O. gradients and incubated them with D.O. concentrations strictly controlled the same as in situ. In
such enrichment cultures, genera Desulfovibrio and Desulfomicrobium were the main sulfate-reducing bacteria, and genera Shewanella
and Sulfurospirillum were the sulfur metabolism-related bacteria associated with SRB. The relative abundances of Desulfovibrio spp.
decreased when D.O. concentration increased. The upper D.O. limit in our enrichment cultures was 6.68 mg/L, significantly higher than
those previously reported in pure cultures or co-cultures, most likely resulted from the contribution of coexisting sulfur
metabolism-related bacteria which may provide ecological niches for Desulfovibrio spp. by consuming residual oxygen.


Denudation Restoration in the Jiergalangtu Sag of the Erlian Basin and Its Significance to Hydrocarbon Accumulation

XUE Zhiwen，QUZhenghui，CHENGJie，WANGYuanjie，MAYousheng，XU Yongzhong

2019, 25(5):  714. 

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The Jiergalangtu sag is one of the important oil production bases in the Erlian Basin. In the early Cretaceous, the Lower
Cretaceous Tenggeer and Saihantala formations experienced two intense uplifts and denudations. The recovery of denudation amount o
sedimentary strata has a great significance for the evaluation of hydrocarbon accumulation. Based on data of mudstone sonic log
interval and vitrinite reflectance, the denudation thickness of the Tenggeer and Saihantala formations in the Jiergalantu sag is
calculated, and the original sedimentary thickness and burial process were restored. Results show that the denudation of the Tenggeer
and Saihantala formations has undergone different degrees under the control of structural inversion. The denudation thickness of the
Tenggeer Formation is about 243-1933 m, and that of the Saihantala Formation is about 95-290 m. The distribution of denudation
thickness is obviously affected by the differential activity of faults in different directions and scales during the tectonic inversion. The
denudation of the Hanni structural belt near the northwestern boundary faults is relatively large, and gradually decreases to the
southeastern gentle slope zone. The difference of denudation amount in different structural parts of the area has a direct impact on
hydrocarbon accumulation. Fault depression area and later inversion controlled large sedimentation and strong denudation area have a
long hydrocarbon generation time of source rock. The denudation and pressure relief of uplift zone formed by structural inversion along
the structural strike are beneficial to the vertical and lateral migration of oil and gas along NE fault plane and the formation of reservoir
in favorable traps on both sides of the fault plane.

Discussion on the Structural Features and Formation Mechanism of Strike-Slip Pull-Apart Basin: A Case Study in the Doseo Basin, Central Africa

KONGLingwu，ZHANG Shulin，HANWenming，ZHAO Hongyan，ZHAO Jiaqi，YU Yingmei

2019, 25(5):  722. 

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Based on the tectonics of the Central African Shear Zone (CASZ), how the CASZ controlled the formation and evolution of
the Doseo Basin was analyzed in this paper. The evolutional stages of the basin were divided, the basin structure was analyzed, and the
formation mechanism of the basin was discussed. Results show that the CASZ developed two periods of strike-slip processes which
were strong and weak, respectively. The strike-slip strength controlled the evolutional stages of the basin, i.e., transtensional,
transpressional and depression stages, The transtensional stage was the main formation stage of the Doseo Basin; in contrast, the
transpressional stage was the structural setting stage of the basin. The eastern and western parts of the basin developed different
strength transpression in the transpressional stage. As such, the basin was formed to a division of eastern main depression and western
transpression zone. The eastern main depression developed weak transpression, and it had asymmetric double-fault structure. In
contrast, the western transpression zone developed strong transpression, stratigraphic deformation, inversion of the Borogop II fault, and
formation of large positive flower structural area. Transtensional and transpressional activities controlled the structural styles of the
Doseo Basin in two types of structural styles and five sub-types. Transtension which was formed in right step-dextral controlled the
formation of strike-slip pull-apart basin.

Applicability Analysis of Different Methods for Extensional Displacement Calculation in Extensional Structures with Application in Qiongdongnan Basin

ZHANG Yingzhao，WANG Wei，GAN Jun，YIN Hongwei，ZHU Jitian，ZHANG Jiaxing

2019, 25(5):  730. 

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We apply three area-balance techniques to a well-constrained experimental sand model of extensional structures. The
bed-length-constant method assumes that bed length and thickness remain constant during deformation, then the extensional
displacement in different stages of deformation can be calculated through flexural-slip restoration. The area-depth-strain method, which
uses the excess/lost areas and depths of several pre-deformation strata to build an area-depth line, can directly give the depth of
detachment and the displacement along it. The area-depth-strain method allows the bed length and thickness to change during
deformation. The area-constant method assumes that the depth of the detachment is known, according to the area balance, and the area
of syn-tectonic sedimentary can be used to calculate the corresponding extensional displacement as well as the total displacement. The
results of the sand model show that the area-depth-strain method and the area-constant method can be well applied to the
pre-deformation strata and syn-tectonic strata, respectively. In addition, the bed-length-constant method can produce extra errors which
may be over 10% and are caused by the shear deformation. The Changchang sag in Qiongdongnan Basin mainly contains the Cenozoic
syn-tectonic strata developed on the Pre-Cenozoic basement. The results of the area-constant-method give the extensional displacements
during the deposition of Lingtou, Yacheng, and Lingshui Formation of 13.8 km, 15 km and 21.4 km, respectively, with the total
amount of displacement and extensional rate of 50.2 km and 42.7%. The results also show that the area-constant method and the
area-depth-strain method are much more reliable than the bed-length-constant method in extensional basins with shear deformation.
The area-depth-strain method can be applied in structures with well constrained pre-deformation strata, and the area-constant method
uses growth strata to calculate the corresponding extensional displacement as well as the total displacement

Structural Coupling of Deep and Shallow Fault Systems in the Nanbaxian Anticline, Northern Qaidam Basin

WANG Yanbo，ZHANG Yongshu，XIAO Ancheng，WANG Liqun，SHEN Ya，WU Lei

2019, 25(5):  741. 

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Abundant basement deep faults and shallow faults are widely developed in the Qaidam Basin, but the genetic mechanism
between the coupling of the diverse faults is still controversial. In this paper, we analyze the geometry and coupling relationship of deep
and shallow fault systems across the Nanbaxian anticline in the northern margin of the Qaidam Basin, by using high-resolution 3D
seismic reflection data and drilling data. Results show that two EW-trending, high-angle basement faults are developed in the
Nanbaxian area, namely, the south-dipping Maxian fault and the north-dipping Xiannan fault. They were both initially formed in the
late Mesozoic and rejuvenated in the Cenozoic. Two sets of shallow normal fault systems are well developed within the Cenozoic in
Nanbaxian. One is NW-striking, and mainly en echelon distributed on the southern side (hanging wall) of the Maxian fault. The other is
EW-striking, and confined in the core of the Nanbaxian anticline above the Xiannan fault. This EW-striking fault cuts the NW-striking
normal fault system, and consists of a series of parallel sub-normal faults, forming a small graben structure within the Cenozoic above
the basement-involved Xiannan fault. We interpret that the NW-striking normal faults are related to extension at the western tail of the
Maxian fault caused by the sinistral strike slip, while the EW-striking normal faults result from local extension caused by thrust of the
high-angle Xiannan fault. Combined with previous research, we conclude that the widely distributed shallow fault systems are of various
origins with a complicated coupling with the deep fault systems in the Qaidam Basin, and that the pre-existing faults played an
important role in the Cenozoic deformation.

Physical Modeling Research on Thermo-Mechanical Behavior of Energy Diaphragm Wall

DONG Shengshi，LI Xiaozhao，XIONG Zhiyong，WEN Jifei

2019, 25(5):  748. 

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Nowadays, the researches on the thermo-mechanical behavior of energy diaphragm wall lacks in contrast to its increasing
significance in energy geostructures worldwide. To study the thermo-mechanical behavior of wall and wall-soil interface under
different heating and constraining conditions, three contrast tests were conducted in a self-made laboratory model chamber. By
analysing the data obtained, this paper presented the change laws of fields regarding heat, vertical strain in wall, and normal stress on
the interface during process. Furthermore, the variations of these parameters revealed the mechanism, in which temperature changes
and constrain changes would influence the thermo-mechanical behavior of energy diaphragm wall.

Experimental Study on Volumetric Shrinkage Behavior of Expansive Soil

WANGDongwei，TANG Chaosheng，LI Shengjie，ZENG Hao，SHI Bin，ZHANG Biyong

2019, 25(5):  756. 

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Expansive soil is a kind of typical soil with problems, which is very sensitive to climate change. it is prone to volumetric
shrinkage deformation under drought conditions, causing various engineering geological problems. In order to study the desiccation
shrinkage deformation characteristics of expansive soil, a series of indoor drying experiments were carried out to determine the
shrinkage characteristic curves of expansive soils, and the effects of initial moisture content and dry density on the shrinkage
deformation process were mainly analyzed. The effect and mechanism of cement solidification on suppressing desiccation shrinkage
deformation of expansive soil are further discussed. The results show that: (1) There are three typical stages in the shrinkage
deformation process of expansive soils: normal shrinkage, residual shrinkage, and zero shrinkage. (2) The higher the initial moisture
content, the faster the evaporation rate of the sample, and the smaller the void ratio of the sample after the shrinkage deformation is
complete, and the larger the final shrinkage strain, the more obvious the shrinkage deformation will be. (3) The larger the initial dry
density, the smaller the sample evaporation rate and the final volume shrinkage strain, and the increase of the initial dry density has a
significantly reduce the volumetric shrinkage strain of the sample, and it has a good suppressive effect on shrinkage deformation. (5)
The dry shrinkage deformation of expansive soil has obvious anisotropic characteristics and is related to the initial state.
certain inhibitory effect on the shrinkage deformation of the sample. (4) Incorporating proper amount of cement in expansive soil can

A New Criterion of Strength Reduction Method for Slope Instability Based on the Slip Line-Field Theory

FANG Hongwei，WU Jianxun，HOU Zhenkun

2019, 25(5):  766. 

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The strength reduction method (SRM) has an advantage over other methods in evaluating slope stability for automatically
determining a critical slip surface. However, a key problem is that there is no corresponding definite standard for an instability criterion
in using SRM. Previous research has shown that slope stability can be determined based on the relative position between the limit-state
slope curve (referred to as the limiting slope curve) obtained from slip-line field theory calculations and the slope. Based on this
conclusion, a set of new SRM-based instability criteria is proposed. The limit slope curve calculated by the slip-line field theory will
change for different strength factors are calculated by different reduction factors. It can be concluded that the slope is in a stable state
when the limiting slope curve does not intersect the slope at the toe. The slope is in a limit-equilibrium state when they intersect at the
toe of the slope while the slope is in an unstable state when the limiting slope curve and the slope intersect. The calculation results of
standard slope test show that when the new instability criterion has an advantage in convergence, safety factor calculated by the new
criterion is close to the existing criterion and the standard answer. For the traditional criterion, there are no guidelines as to the choice
of a tolerance criterion and the optimal number of iterations, and it is not always easy to find the sharp break point immediately after a
slope failure, especially when the displacement curve is relatively smooth. Also, it is difficult to define a precise safety factor from this
criterion, moreover, the evaluation criterion with a presumed allowable iteration number is influenced by an artificial factor. The
objective quantification of the instability criterion can be realized by the new instability criterion. The critical slip surface shape and
position determined by the plastic strain in the slope are basically the same as the standard answer. The new instability criterion is
applicable for the strength reduction method.

Statistical Analysis of Landslides Law Caused by Rainfall in Zhenjiang Area

YAN Xiaoying，YAN Changhong，GAO Zezheng

2019, 25(5):  772. 

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Zhenjiang is located in a hilly area in Jiangsu Province. In recent years, investigation data shows that short-term strong
rainfall or long-lasting rainfall in Zhenjiang area often induced a large number of shallow landslides. So, rainfall is the main influencing
factor of landslides in Zhenjiang area, which has caused great economic losses. In this paper, more than 300 mountain slopes in
Zhenjiang area were investigated in detail, and the relationships between landslides and rainfall related parameters were analysed
based on meteorological data. The relationships between rainfall, duration and the number of landslides were obtained. The I-D curve
of rainfall threshold in Zhenjiang area was determined, and the analysis results were compared with those in other areas. The research
results provided a basis for landslide control, early warning and prediction in Zhenjiang area.

Paleomagnetism of the Upper Cretaceous Aeolian Red Beds in Xinjiang Basin, Jiangxi Province, China

LUO Xi，LI Yongxiang，LI Xianghui

2019, 25(5):  779. 

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Red bed is one of the important targets in paleomagnetic studies. Previous research has focused mainly on paleomagnetism
of lacustrine-fluvial red beds, while paleomagnetism of aeolian red beds has been rarely investigated. As a result, the reliability of
paleomagnetic data from aeolian red beds and the remanence acquisition in different depositional processes remain poorly understood.
In this study, we carried out a paleomagnetic study of the Upper Cretaceous aeolian red beds from the Tangbian Formation (Fm) and
lacustrine-fluvial red beds from the Hekou Fm of the Guifeng Group in Xinjiang Basin, Jiangxi Province, China. The purposes of this
study are to investigate the reliability of the paleomagnetic records of aeolian red beds and the influence of different depositional
processes on magnetic remanence acquisition by comparing the paleomagnetic data of aeolian red beds and those of lacustrine-fluvial
red beds. Stepwise thermal demagnetization of the samples shows that only 19% of the aeolian red beds samples of Tangbain Fm yield
stable characteristic remanent magnetizations (ChRMs) with convex intensity decay curves, indicating a primary origin of remanence
carried by detrital hematite grains. The mean of the ChRMs of the Tangbian Fm is Ds=15.6 °, Is=28.9 °, n=25, κ=13.0, α95=8.3 ° after
tilt correction, corresponding to a Late Cretaceous paleopole at Latitude=70.7 °, Longitude=245.6 °, A95=6.8 °. The new paleopole is
indistinguishable with the coeval paleopole from lacustrine-fluvial red beds of the Ganzhou area and the recently updated Late
Cretaceous paleopole of South China, suggesting that the aeolian red beds of the Tangbian Fm can carry reliable paleomagnetic records.
Most lacustrine-fluvial red bed samples from the Hekou Fm failed to yield stable ChRMs. The anisotropy of magnetic susceptibility
(AMS) data of the Tangbian Fm and the Hekou Fm indicate sedimentary fabrics. Rock magnetic results of representative samples show
that remanence are carried by hematite and magnetite. Further investigations of the Tangbain Fm aeolian red beds with thin section
observations and redness analysis indicate that particle size and degree of cementation may affect the stability of remanent
magnetization of aeolian red beds.

Luminescence Dating of Loess Gully Terraces in the Yangshao Man Site at Mianchi County, Henan Province

ZENG Qiongxuan，SUN Xuefeng，YI Shuangwen，JIA Xin

2019, 25(5):  791. 

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The relationship between geomorphological evolution and human activities is an important issue in geography research. The
Yangshao site in Mianchi County, Henan Provence, is one of the most significant Neolithic pottery cultures in the Yellow River Basin.
This study takes Xigou Gully in the Yangshao site in Mianchi County as a research object, and try to establish the relationship between
human activity and landform formation. The Yangshao Site is located in the southeastern boundary of Loess Plateau. This plateau is a
loess accumulation area, and loess is an ideal material for optically stimulated luminescence (OSL) dating. In this study, we used quartz
OSL dating and K-feldspar post-infrared(IR) IRSL to obtain the age of overlaying loess in the Xigou Gully terraces and attempt to
reconstruct the formation time of the terraces. The formation of the terraces in Xigou Gully has been estimated at approximately 30 ka
and 120 ka, corresponding to the marine isotope stage (MIS) 3 and 5. However, given the absence of a record of human activity in the
Yangshao Site during this period, our dating results prove that the formation of gullies in the site has no relationship with the surface
activities of the Yangshao people during the Neolithic Age.