Digital topographic analysis, an important means in the research of active tectonics and tectonic geomorphology, has increasingly become one of the principal tools in the identification of active tectonic features and understanding of the development of the earth’s surface process. Indoor interpretation of surface fault trace plays a key role in the digital topographic analysis as it can provide the foundation for setting priorities and defining strategies in the subsequent field investigation. At present, the extraction of fault traces is often realized by assisting the traditional visual interpretation through the image enhancement method. The relevant subjective assessments lead to the amount of work and usually cause different results due to the differences in the interpretation experience of actual operators. At the same time, the field of quantitative research on geomorphic parameters is evolving very rapidly with the advances in the popularity of high-resolution digital topographic data. Therefore, intelligent and automatic extraction of surface fault traces has gradually become a promising research direction. The methods based on machine learning often rely heavily on the good programming foundation of the operator, which is a visible technical barrier. We present a semi-automated method using an ArcGIS toolbox with a set of tools to extract surface fault traces based on geomorphic constraints. The Hutubi and Dushanzi faults are two typical thrust faults located on the northern piedmont of the Tianshan Mountains and are chosen as examples. Excellent exposure of the surface fault traces in these two regions permits detailed mapping of fault traces and deriving shape factors of faults with high-resolution DEMs(digital elevation models). Additionally, they are two of the most-studied thrust faults in this area. Large-scale geological and geomorphological mappings of them and numerous achievements have been published. This creates possibilities for us to conduct comparison analysis on different major methods. Based on typical morphology characteristics of fault scarps, appropriate geomorphic parameters are selected. In practice, reverse fault scarps are distinctly defined into forward and backward ones according to whether their dip is the same as that of the neighboring geomorphic surfaces. Based on two sets of geomorphic constraints,two approaches are then illustrated, including slope calculation, gully extraction, data density analysis and process modeling. Through a detailed comparison of the final extraction results and previous visual interpretations of remote sensing data and field geomorphic investigations, the validity of the method proposed in this study is proven. This method provides a set of tools with user-friendly interfaces to realize step-by-step interpretation and emphasizes the importance of field-based geomorphic constraints at the same time. Moreover, many subtle fault traces which have not been recognized before are simultaneously revealed in the Dushanzi research area. The high-resolution DEMs guarantee the realization of picking out finer bits of fault information. Compared to traditional ways of working, the method has the advantage of automatically delineating reverse fault traces on the earth’s surface. This advantage can significantly reduce the efforts to manually digitize geomorphic features and improve efficiency. But many basic manual adjustment options for recognizing target characteristics also need to be set in extraction, because the distinguishing criterion of fault scarp and surrounding geomorphic landforms vary among different areas. In different specific circumstances, users can manually adjust relevant parameters for the extraction during the modeling process. Generally speaking, the more detailed constraints, the more confidence in the final delineation of fault traces. Subjective judgments are therefore particularly critical for conducting extraction under complex backgrounds. But improving the degree of automation of the whole process is still an important study direction. Future work is thus recommended to employ machine learning and explore appropriate evaluation methods to search for the optimal solution of intermediate parameters.

The top of the piedmont alluvial fan has the characteristic of fan-shaped terrain and gradually descending terrain in the downstream direction. Faulting of various natures will result in different geomorphic features of alluvial fan surface. The variation of slope aspect and height of the pure sinistral fault scarp at the top of the alluvial fan is analyzed firstly under the three conditions, namely, the fault plane is vertical, the fault plane inclines toward the upper stream of the river, and the fault plane inclines toward the downstream of the river. We have also analyzed the variation of slope aspect and height of the fault scarps at the top of the alluvial fan under different fault inclination conditions of inverse sinistral strike-slip fault and the sinistral strike-slip normal fault. The seven geomorphic types we analyzed above cover the geomorphic features caused by the activity of strike-slip faults at the top of alluvial fans, which can help us to analyze the formation of the landforms. Based on drone-measured terrain data, Google satellite images and field investigations, we found that the Dongbielieke Fault, which strikes northeast-southwest and is located in the eastern margin of the Tacheng Basin, Xinjiang, almost vertically passes through the Ahebeidou River which develops from southeast to northwest. The direction of central axis of the alluvial fan at Ahebedou River is northwest, with a north-facing slope. The fault activity has caused the development of an uphill-facing scarp that has a height of~5.2m and a slope aspect facing southeast on the top of the alluvial fan at the Ahebiedou River section of the Dongbielieke Fault. And on the piedmont alluvial fan 1km away on both sides of the river bed, the sinistral fault scarps have a northwest-facing slope aspect and a height of 1~5m. The river terraces are divided into five levels, the T2 on the left bank, T4 on the right bank and T5 terraces on the left and right banks of Ahebeidou River were affected by fault activity. Sinistral offsets and southeast-facing fault scarps were developed on the geomorphic surface. By using DispCalc_Bathy_v2, a script based on Matlab, we get the offsets of the river terraces from the high-resolution DEM data obtained by using UAV photogrammetry technology. The sinistral horizontal offsets of T2 on the left bank, T4 on the right bank and T5 terraces on the left and right banks of Ahebeidou River are(10.1±0.2)m, (10.6±0.7)m, (29.1±0.2)m and(20.0±0.7)m, respectively. The vertical displacements are(1.5±0.1)m, (3.6±0.3)m, (4.7±0.2)m and(5.2±0.1)m, respectively. The asymmetrical development of terrains on both sides of the river is affected by topography and fault activity. The terraces on the lower elevation right bank of the river are misplaced into the channel by sinistral strike-slip faulting to receive more erosion, so the offsets we measured on the left bank of the river are more reliable than that on the right bank. Through field surveys, we found two fault outcrops, indicating that the fault plane is inclined to the southeast. The young river terrace T2 was effected by faulting and a uphill-facing scarp was developed, which indicates that the latest faulting was of sinistral strike-slip with a normal component, but the fault scarp's aspect changed twice within a short area of two kilometers, which is not consistent with the geomorphological type caused by the strike-slip faulting on the top of the alluvial fan as we previously analyzed. According to the landform features and the strike-slip fault geomorphic model, a model for the geomorphic surface development of the Ahebiedou River section is established. In this model, we think the Dongbielieke Fault was an inverse sinistral strike-slip fault after the formation of an older phase geomorphic surface S1 in the area. The early fault activity formed a northwest-facing fault scarp at S1, the height of the scarp is about 10m. Then the alluvial fan(Fan1)began to develop, and the material brought by the flowing water deposited and buried the fault scarp at the exit of piedmont, resulting in the disappearance of the existing fault scarp in the piedmont. Then the characteristic of fault changed into left-lateral strike-slip with a normal component. The activity of normal fault with the fault plane dipping to SE would form a fault scarp facing SE on the geomorphic surface. With the gradually cutting of the river, river terraces began to form on both sides of the river, and the corresponding geomorphic features were formed under the influence of fault activities. A fault scarp with a slope facing southeast formed at both banks of the river's mountain outlet with a height of about 5.2m through several fault activities, and sinistral horizontal offsets of river terraces increased at the same time. And the height of the pre-existing northwest-facing scarp 1~2km away from both banks of the river's mountain outlet decreased to about 5m, which can be observed in the field. The eventual geomorphic surface is characterized by the features of downhill-facing scarp-no scarp-uphill-facing scarp-no scarp-downhill-facing scarp from southeast to northeast.

The Talas-Fergana Fault(TFF)with a total length of more than 1 000km is a large dextral strike-slip fault across the West Tianshan Mountains in the northwest direction. The fault plays an important role in accommodating deformation in Central Asia and has attracted much attention by geologists due to the huge controversy in its strike-slip rate and kinematic pattern. Previous studies indicated that its average dextral strike-slip rate is 8~20mm/a since Late Holocene based on offset ephemeral stream valleys and ¹⁴C dating method. Some researchers recently updated the strike-slip to 2.2~6.3mm/a by the application of multiple dating methods(¹⁰Be, ²⁶Al, ³⁶Cl, luminescence, and radiocarbon)and satellite images with higher precision. But the strike-slip rates derived from modern GPS velocity field are only~2mm/a or even as low as 0.8mm/a. Thus, there is a substantial divergence between geological results and geodetic results in the strike-slip rate of the TFF. Some scholars believe that the huge difference between the geological rate and the rate obtained by geodetic measurements is caused by fault locking. In this study, the updated GPS data was used to establish velocity field of the West Tianshan Mountains relative to the stable Eurasian framework and the velocity field without self-rotation. The velocity field shows that the Tianshan Mountains are under intense crustal shortening and deformation. Moreover, for the TFF, as an important boundary fault in the western Tianshan Mountains, whether the far velocity field or the near velocity field, the differential movement of the crust is not obvious. And far-field velocity vectors away from the TFF show that there is minor difference of crustal movement along the fault. The TFF does not have the typical characteristic of locked fault that there is a big difference in velocities of far-field vectors, but a small difference in that of near/mid-field vectors. Thus, the activity of the fault is weak actually.
To further illustrate the overall low slip rate of the TFF, we compare the maximum shear strain rate and its distribution characteristics along the Altyn Fault and the Haiyuan Fault with large slip rates with the results of the TFF. The maximum shear strain rates along the Altyn Fault and the Haiyuan Fault are concentrated along the fault, and are as high as~60nano strain/a and~40nano strain/a, which are much larger than the overall maximum shear along the TFF. This shows that the sliding rate of the TFF is much lower than the strike-slip rate of the Altyn Fault of 9~15mm/a, and even slightly lower than the sliding rate of the Haiyuan Fault of 4~8mm/a. Therefore, we are more certain that the current activity rate of the TFF is far less than 8~20mm/a estimated by some geological methods.
The half-space elastic dislocation model is used to more rigorously re-constrain the current strike-slip rate of the TFF. The results show that the fault is divided into three segments. The TFF dextral strike-slip rate increases from the northwest section to the middle section and decreases from the middle section to the southeast section. And the strike-slip rates of the northwestern, middle and southeastern segments are(2.1±0.7)mm/a, (3.3±0.4)mm/a and(2.4±0.7)mm/a, respectively. The TFF is dominated by strike-slip motion, but there is also a weak dip-slip motion in the middle section of the TFF, with a magnitude of about 1mm/a.
The above results confirm the current low strike-slip rate of the TFF obtained by GPS which is much less than the strike-slip rate of 8~20mm/a estimated by geological methods. And through the GPS results, it is certain that the TFF presently has a low fault activity rather than a locked fault. To reconcile the high geological strike-slip rates and the geodetic results, a new deformation pattern of the West Tianshan Mountains may be needed. And more detailed GPS observations are required to explore whether the TFF has penetrated into the southern foreland basin of the West Tianshan Mountains.

In response to the ongoing far-field effects of the India-Eurasia collision, the Tianshan Mountains experience rapid NS convergence, and most of the present N-S shortening is absorbed along the southern and northern edges. The resultant frequent large earthquakes have inspired many scientists to explore the neotectonic activity of the Tianshan Mountains. The eastern Qiulitage anticlinal belt located in the Kuqa depression, on the southern piedmont of the Tianshan Mountains, is a typical blind fault-related fold. The Kuqa M7$\frac{1}{4}$ earthquake in 1949 as typical folding earthquake once occurred on the northern limb of the eastern segment of the Qiulitage anticline, and the epicenter was near the Village of Kang which is sparsely populated. This earthquake is a typical folding earthquake whose dominant fault did not thrust onto the earth surface. Although many tectonic-induced scarps and deformed Quaternary strata have been reported, there are still no direct evidences for the surface ruptures and corresponding causative faults of this earthquake at present. And systematic understanding of paleoseismic events in Qiulitage area is also limited by the lack of relevant chronological researches.
We conducted 1︰50 000 scale geological mapping in the Qiulitage anticline area. The local surface geological characteristics are investigated based on interpretation of Google Earth image and confirmation in the field. Together with interpreted subsurface structure by petroleum seismic reflection profiles, the relationship between the active faults thrust on the surface, low-dip-angle decollement faults in deep, and fold deformation are subsequently qualitatively analyzed. In this study, the active faults which have thrust to the surface and generated fault scarps are focused on.
Totally five trenches were chosen and cleared up, two of which are located on the southern limb of the eastern Qiulitage anticline and the others are on its northern limb. And all excavation sites are situated on fresh fault scarps. We carefully interpreted different characteristics of tectonic deformation and sedimentary process which are correlated with paleo-seismic events from trenches. According to the OSL(Optically Stimulated Luminescence)and ¹⁴C dating results, a reliable chronological framework for the deformed stratigraphic sequences was established. Based on the classic successive limiting method, six paleoseismic events were finally constrained.
Some of these interpreted paleo-seismic events produced surface ruptures on the breakthrough faults simultaneously on the southern and northern limbs of the Qiulitage anticline, and others only caused local surface ruptures on its northern limb. In a broad sense, the surface ruptures caused by these paleoseismic events have similar characteristics to those which are popular among the low-dip-angle thrust faults on the southern piedmont of the Tianshan Mountains. And the two common phenomena are that multiple ruptures may occur a single fault and multiple faults may rupture simultaneously. We speculate that only when the displacement of master faults at depth is big enough, multiple shallow secondary faults can be triggered at the same time. Conversely, only one fault is active at one time. In other words, constrained by the length and displacement of dominant faults, not all paloseismic events can cause surface ruptures on the northern and southern limbs of the Qiulitage anticline at the same time.
The revealed paleoearthquakes may have a clustering feature since ~7.4ka. They behaved as follows: 1)Three events occurred during 5.7~7.4ka. 2)one event occurred during 3.3~4.7ka. 3)the latest cluster of events may be marked by the 1949 M_W7$\frac{1}{4}$ Kuqa earthquake. Thus, the earthquake sequences have a recurrence period of about 2.5~4ka.
Significantly, the incompleteness of the paloseismic events recorded in trenches and the quality and intrinsic error of the OSL dating samples can mislead judgments. It is inevitable that the time of paloseismic event cannot be constrained strictly. In our research area, because of the lack of seismic events between event E5 and event E6(7.25~19.1ka), there is a gap in seismic event records for up to~11.85ka. However, our result offers a relatively systemic event sequence to fill the gap in studies on paleoseismicity in this area. Whether there will be a strong shock after the 1949 M_W7$\frac{1}{4}$ Kuqa earthquake remains to be further studied in detail.

Earthquake events are one of the most extraordinarily serious natural calamities, which not only cause heavy casualties and economic losses, but also various secondary disasters. Such events are devastating, and have far-reaching influences. As the main disaster bearing body in earthquake, buildings are often seriously damaged, thus it can be used as an important reference for earthquake damage assessment. Identifying damaged buildings from post-earthquake images quickly and accurately is of real importance, which has guidance meaning to rescue and emergency response. At present, the assessment of earthquake damage is mainly through artificial field investigation, which is time-consuming and cannot meet the urgent requirements of rapid emergency response. Markov Random Field(MRF)combines the neighborhood system of pixels with the prior distribution model to effectively describe the dependence between spatial pixels and pixels, so as to obtain more accurate segmentation results. The support vector machine(SVM)model is a simple and clear mathematical model which has a solid theoretical basis; in addition, it also has unique advantages in solving small sample, nonlinear and high-dimensional pattern recognition problems. Thus, in this paper, a Markov random field-based method for damaged buildings extraction from the single-phase seismic image is proposed. The framework of the proposed method has three components. Firstly, Markov Random Field was used to segment the image; then, the spectral and texture features of the post-earthquake damaged building area are extracted. After that, Support Vector Machine was used to extract the damaged buildings according to the extracted features. In order to evaluate the proposed method, 5 areas in ADS40 earthquake remote sensing image were selected as experimental data, this image covers parts of Wenchuan City, Sichuan Province, where an earthquake had struck in 2008. And in order to verify the applicability of this method to different resolution images, an experimental area was selected from different resolution images obtained by the same equipment. The experimental results show that the proposed method has good performance and could effectively identify the damaged buildings after the earthquake. The average overall accuracy of the selected experimental areas is 93.02%. Compared with the result extracted by the widely used eCognition software, the proposed method is simpler in operation and can improve the extraction accuracy and running time significantly. Therefore, it has significant meaning for both emergency rescue work and accurate disaster information providing after earthquake.

Landslides and rock falls along the highway are common geological hazards in Southwest China. As an influencing factor on potential landslides behavior, roads or distance to roads have been successfully used in landslide susceptibility assessments in mountainous area. However, the relationship between the road-cut and the slope stability is not clear. Therefore, we performed two-dimensional slope stability calculation using the general limit equilibrium (GLE)method incorporated in the software SLOPE/W of GeoStudio for stability analysis of slopes. Our studies show that the man-made roads influence on the slope stability mainly exists in two ways:One is to create a new steep slope, which will result in rock falls and shallow landslides along the roads; the other is to influence the stability of the original slope, which will result in comparatively huge landslides. For the latter, our simulation study reveals that the road location, namely at which part of a natural slope to construct a road is important for the slope stability. For a natural slope with a potential slip surface, if a road is constructed at or near the slope toe where the potential slip surface surpasses, it will greatly degrade the slope's factor of safety (Fs) and make the slope unstable; however, if a rode-cut is near the top of the slope, it will increase the slope's Fs and make the slope more stable. The safety location is different for different slope angle, steeper slope needs a higher location for a safety road-cut in comparison with gentle slopes. Moreover, the slope stability decreases when loading a seismic force and it varies with the slope angle. Firstly, the Fs decreases when the slope angle increasing, and when the slope angle reaches 45°, the Fs then becomes greater with the slope angle increasing.

On August 3, 2014, an M_W6.5 earthquake occurred in Ludian County, Yunnan Province, which triggered significant landslides and caused serious ground damages and casualties. Compared with the existing events of earthquake-triggered landslides, the spatial distribution of co-seismic landslides during the Ludian earthquake showed a special pattern. The relationship between the co-seismic landslides and the epicenter or the known faults is not obvious, and the maximum landslide density doesn't appear in the area near the epicenter. Peak ground acceleration (PGA), which usually is used to judge the limit boundary of co-seismic landslide distribution, cannot explain this distribution pattern. Instead of correlating geological and topographic factors with the co-seismic landslide distribution pattern, this study focuses on analyzing the influence of seismic landslide susceptibility on the co-seismic distribution. Seismic landslide susceptibility comes from a calculation of critical acceleration values using a simplified Newmark block model analysis and represents slope stability under seismic loading. Both DEM (SRTM 90m)and geological map (1 ︰ 200^￣￣000)are used as inputs to calculate critical acceleration values. Results show that the most susceptible slopes with the smallest critical accelerations are generally concentrated along the banks of rivers. The stable slopes, which have the larger critical accelerations and are comparably stable, are in the places adjacent to the epicenter. Comparison of the distribution of slope stability and the real landslides triggered by the 2014 M_W6.1 Ludian earthquake shows a good spatial correlation, meaning seismic landslide susceptibility controls the co-seismic landslide distributions to a certain degree. Moreover, our study provides a plausible explanation on the special distribution pattern of Ludian earthquake triggered landslides. Also the paper discusses the advantages of using the seismic landslide susceptibility as a basic map, which will offer an additional tool that can be used to assist in post-disaster response activities as well as seismic landslides hazards zonation.

Based on geological and geomorphologic characteristics of the surface faults acquired by field investigations and subsurface structure from petroleum seismic profiles, this paper analyzes the distribution, activity and formation mechanism of the surface faults in the east segment of Qiulitage anticline belt which lies east of the Yanshuigou River and consists of two sub-anticlines:Kuchetawu anticline and east Qiulitage anticline. The fault lying in the core of Kuchetawu anticline is an extension branch of the detachment fault developed in Paleogene salt layer, and evidence shows it is a late Pleistocene fault. The faults developed in the fold hinge in front of the Kuchetawu anticline in a parallel group and having a discontinuous distribution are fold-accommodation faults controlled by local compressive stress. However, trenching confirms that these fold-accommodation faults have been active since the late Holocene and have recorded part of paleoearthquakes in the active folding zone. The fault developed in the south limb near the core of eastern Qiulitage anticline is a low-angle thrust fault, likely a branch of the upper ramp which controls the development of the eastern Qiulitage anticline. The faults lying in the south limb of eastern Qiulitage anticline are shear-thrust faults, which are developed in the steeply dipping frontal limb of the fault-propagation folds, and also characterized by group occurrence and discontinuous distribution. Several fault outcrops are discovered near Gekuluke, in which the Holocene diluvial fans are dislocated by these faults, and trench shows they have recorded several paleoearthquakes. The surface anticlines of rapid growth and associated accommodation faults are the manifestations of the deep faults that experienced complex folding deformation and propagated upward to the near surface, serving as an indicator of faulting at depth. The fold-accommodation faults are merely local deformation during the folding process, which are indirectly related with the deep faults that control the growth of folds. The displacement and slip rate of these surface faults cannot match the kinematics parameters of the deeper fault, which controls the development of the active folding. However, these active fold-accommodation faults can partly record paleoearthquakes taking place in the active folding zone.

Fold-accommodation faults, secondary faults subordinated to the principal fold, are of much significance to accommodate strain variation in different parts of the rock during the evolution of folding. They are generally found in groups. And each of them has limited displacement and does not connect with the main detachment. After the geological survey in the East Qiulitage anticline zone, we find that the secondary faults accompanying fold scarps in this area are out-of-syncline thrusts and also give an instance of secondary faults occurring later than the folding. The fact that the secondary faults in fold scarps force the hanging wall to move upward relative to the footwall not only makes the terrace tilting and increases the slope of fold scarps, but also affects the authenticity in calculating regional shortening increment. The theoretical results show that if we do not consider the increased fold scarps height influenced by the secondary faults, the shortening increment is 51.42m. Otherwise, the value will be 45.23m and the difference between them is 6.19m. Because the deviation is 13.7% of the total shortening increment, the contributions of fold-accommodation faults to the calculation should not be ignored. The fold scarps in the northern and southern flanks of the East Qiultiage anticline depend on same bedrock type and formation mechanism. But three levels of fold scarps were found in the cross section of less than 300 meters in horizontal distance. This fact indicates that the active kink band of northern part is more closed because of higher compressive stress and faster lifting, which produce a large number of secondary faults in the fold scarps only in the northern flank. Therefore, the study of secondary faults is of significance in understanding of regional tectonic evolution and interaction between folds and faults. But there still exist many problems: 1)Limited by the observing scope, discontinuous distribution of secondary faults and variations of displacement along fault, we may underestimate the influence of secondary faults and the theoretical result should be the minimum. 2)What is the quantitative relationship among the increased height of fold scarps, the transfer slip and the dip of secondary faults?3)If secondary faults only grow in active kink band, how will they affect fold scarp?More examples of fold-accommodation faults are needed for further research.

How strain is distributed and partitioned on individual faults and folds on the margins of intermontane basins remains poorly understood. The Haermodun(Ha) anticline, located along the northern margin of the Yanqi Basin on the southeastern flank of the Tian Shan, preserves flights of passively deformed alluvial terraces. These terraces cross the active anticline and can be used to constrain local crustal shortening and uplift rates. Geologic and geomorphic mapping, in conjunction with high-resolution dGPS topographic surveys, reveal that the terrace surfaces are perpendicular to the fold's strike, and display increased rotation with age, implying that the anticline has grown by progressive limb rotation. We combine ¹⁰Be terrestrial cosmogenic nuclide(TCN) depth profile dating and optically stimulated luminescence(OSL) dating to develop a new chronology for the terraces along the Huangshui He since 550ka. Our in situ ¹⁰Be dating of fluvial gravels capping strath terraces suggests a relationship between the formation and abandonment of the terraces and glacial climate cycles since the middle-late Pleistocene. These data indicate that the formation of the four terraces occurred at ~550, ~430, ~350, and~60ka. We suggest that episodes of aggradation were facilitated by high sediment supply during glacial periods, followed by subsequent incision that led to abandonment of these terraces during deglaciation. Combining uplift and shortening distance with ages, we found the vertical uplift gradually decreased from 0.43 to 0.11mm/a, whereas the shortening rate was constant at ~0.3mm/a since the anticline began to grow. The shortening rates of the Ha anticline from geomorphology agree with current GPS measurements, and highlight the importance of determining slip rates for individual faults in order to resolve patterns of strain distribution across intermontane belts.

With rapid improvement in resolution of three dimensional topographic data, more and more high-resolution remote sensing data are applied in the study of geomorphology and seismo-geology. The contour map, hill shading map and hypsometric tint map are original visualization methods of plan view for three dimensional topographic data. They all have their own advantages and have been widely used in screen display and plane graphics, and they usually are mixed and merged to enhance the expression ability of information as a complement to each other. But the results still can not completely satisfy the demand of displaying and exploring the hiding information. As a result, how to utilize sufficiently the high-resolution remote sensing data and various visualization methods to make better expression of topography and detect small geomorphic features has been concerned by many scientists.
A new topographic parameter, termed openness, and a new visualization method, termed RRIM, have been developed to enhance the three-dimension effect and produce a fine image of topographic structure with no shade, which does not need any professional ability for its audiences and additional instruments. In the meanwhile, the RRIM has the incomparable predominance in identifying the subtle tectonic geomorphic features, which is very important in the research of geomorphology. If the three dimensional topographic data have the highest resolution and positioning accuracy relative to the hand-held measuring devices in field work, the geomorphologic interpretation work indoors will take place of the field work in a large extent. As a result, the new visualization not only can improve work efficiency, but also reduce the amount of field work. For forest area, tough natural conditions area and no access area which are of research value, RRIM provides a better method and has an important practical value.
Finally, we hope that the new visualization method can play a larger role in geomorphologic interpretation work, especially in active tectonics research and active fault mapping.

The Hejing reverse fault-fold zone locates on the northern margin of the Yanqi Basin which lies in the south Tianshan Mts.The zone has been growing since early-Quaternary till now.The Xiaermudeng and Haermodun anticlines in the western of Hejing reverse fault-fold are discussed in this paper.Based on the analysis of satellite images and DEM(digital elevation model)data with the spatial resolution of 25m as well as field observation,our results suggest that the Xiaermudeng and Haermodun anticlines have uplifted and propagated laterally during the late Quaternary.Stream-flow direction,topographic sections,decrease of elevation of wind gap and hypsometric analysis indicate that Xiaermudeng anticline uplifted preceding the Haermodun anticline.We also believe that the Xiaermudeng anticline grows laterally from middle to side and Haermodun anticline grows laterlally from west to east.The flows crossing the anticline have diverted eastward under the tectonic movement during the Quaternary,producing a series of wind gaps with straths lowering from west to east.In the Xiaermudeng anticline area,from middle to the side,the drainage density(Dd)is decreased(5.37km^-1 to 2.65km^-1 and 3.07km^-1),and the slope of catchment is increased.The anticline of Haermodun shows a main deformation pattern of uplift and lateral propagation from west to east.The drainage density is decreased(3.87km^-1 to 2.37km^-1),the catchment has steep slope(4° to 6°),the hypsometric curve is from concave-convex to concave-down and the hypsometric integral (∫) is increased(0.45 to 0.76),Moreover,11 topographical cross-sections transecting the anticlines also reveal the lateral propagation from west to east of the Hejing reverse fault-fold zone.

Using the aerial remote sensing photos and Google earth satellite images,we find seven terraces at the both sides along the Kuytun River in Dushanzi active anticline area,northern piedmont of Tianshan.Based on the field investigation,we find that all these terraces are pedestal terraces.The rock of pedestal is Pliocene mud rock,and on the top of each terrace pedestal are the stratums of sandy gravel or sandy clay with 2.5～15m in thickness.We collected samples from deposits of all terraces for OSL(optically stimulated luminescence)geological dating using the SMAR(single-multiple-aliquot-regeneration)method on fine grains.We also performed dating using the ¹⁴ C method to the samples from the deposit of terrace T₁ of the Kuytun River.The results show that the ages of all these deposits are the later phase of the Late Pleistocene.The accumulation time of the upper stratum for T₁,T₂,T₃,T₅,T₆and T₇ terraces is about 1.7ka,14.98ka,20.7～27.3ka,29.3～39.2ka,47～56ka and 103～118ka,respectively.Combining with late Quaternary climate change,we believe that the formation age for T₁～T₇ terraces of Kuytun River are 1.7ka,14ka,20ka,25ka,30ka,50ka and 100ka BP.Paleoearthquake data reveal that eight paleoearthquake events occurred on the Dushanzi-Anjihai reverse fault since about 25ka BP,respectively at 2ka,3.4ka,4.3ka,5.8ka,7.5ka,12.8ka,18ka and 24ka BP.Comparing the ages of paleoearthquakes and terraces,we find that the ages of the latest,the sixth,the seventh and the eighth paleoearthquake are roughly corresponding to the formation times of T₁,T₂,T₃and T₄ terraces,respectively.The other four paleoearthquake events occurred during the period after the formation of T₂and before the formation of T₁.In this time,no terraces developed along the Kuytun River,but the Kuytun River incised rapidly for 40m.We believe that the paleoearthquake events resulted in the fast uplift of Dushanzi active anticline on the hanging wall of Dushanzi-Anjihai Fault and the increase of riverbed slope and river incision ability,which led to the formation of river terraces or deep canyons.The terrace sequence in active anticline region may reflect the paleoearthquake sequence associated with fault or blind fault.