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In recent years, the pitching sliding sleeve staged fracturing technology of open hole packer of horizontal well is widely used in shale gas, dense reservoirs, low permeable reservoirs and other exploration and development fields, and becomes the important means of present oil-gas field stimulation. But in the construction process of horizontal well fracturing, the abnormal condition that the sliding sleeve is not opened or is opened invisibly is occurred repeatedly, which has big impact on the fracturing construction. Based on fluid dynamics method and Finnie micro-cutting theory, this paper simulated the erosion wear rate of ball seat at the different fracturing segments. The results showed that: the construction displacement has big impact on the erosion wear, followed by the particle size of proppant and sand ratio, wherein the erosion wear is in inversely proportional to the particle size of proppant; and when multistage fracturing, the possibility that the sliding sleeve close to the toe end and heel happens erosion destruction is much less than that of sliding sleeve in the middle.

According to the sap flow characteristics and photosynthetic characteristics of Haloxylon ammodendron and Tamarix, we measured the sap flow with the method of thermal diffusion. To monitor photosynthesis with application the instrument CI-340, and the result shows that: (1)The daily net photosynthetic rate change of Haloxylon ammodendron is a typical double peak type, and Tamarixs is a single peak type; (2)The daily transpiration variation of Haloxylon ammodendron is similar to net photosynthetic rate change rule, it has a phenomenon which we called noon break, Tamarixs isnt obvious, it presents volatile changes slightly; (3)The daily sap flow of Haloxylon ammodendron is a typical double peak type, Tamarixs isnt obvious, it presents volatile changes slightly, and at sometimes the sap flow of branches is greater than the breasts. The results provide some supports for ecological water demand of the plants. It has some significance for ecological environment construction of the Gurbantunggute Desert.

The plants' sap flow can characterize water transpiration and consumption, reflect water transmission situation and then determine the vegetation ecological water requirement. This paper takes Haloxylon ammodendron and Tamarix as the research object, adopts thermal diffusion method[1], studies vegetation trunk fluid flow characteristics and the relationship between the meteorological factors. The results show that: (1) Haloxylon ammodendron and Tamarix's sap flux density are showed obvious diurnal variation rule, there is a "nap" phenomenon. Haloxylon ammodendron's liquid sap flux density of monthly mean performance is July > June >August, and Tamarix is July > August >June. (2) Haloxylon ammodendron's flow start time in cloudy is delayed about 1 ~ 1.5 h or so than in sunny day, and Tamarix is about 0.5 h delay. (3) Haloxylon ammodendron and Tamarix's fluid sap flux density in each month are significantly related to meteorological factors, through the regression analysis, Haloxylon ammodendron and Tamarix's trunk liquid sap flux density can make a regression model with meteorological factors.

This study used synchronized acoustic and optical nondestructive AE and ESPI technology with an inclined shear test to investigate the micro- and macroscopic failure mechanisms of cement mortar specimens under shear force. Crack opening displacement feedback was used to control stable damage to obtain complete loading curves of specimens sheared at different shear angles (β). AE technology was used to investigate the time and space distributions of the occurrence of microseismic sources produced by shearing within rocks. Synchronized comparisons were made using the interference images caused by the exterior of the rock material changing shape because of the shearing detected by electronic speckle pattern interferometry (ESPI). This was then used to examine three characteristics of the fracture evolution of rock-like material: localization, initiation of cracks, and crack propagation. The results indicate that shearing stiffness and shear strength are reduced following increases in the shear angle. In addition, the fracture propagation angle tends to change direction and its value also increases. Using AE methods to observe the evolution of microcracks in materials, the time and position of their localization were determined. These results were then compared with the crack initiation and propagation positions detected using ESPI. It is found that the fracture trends observed using these two methods were largely identical.

Orogenic growth, characterized by formation and forward propagation of fold‐thrust belts and foreland basins, is predicted by wedge models of thrust systems. The growth of the Nanpanjiang fold‐thrust belt and foreland basin system of the Indosinian orogenic belt in the southwestern South China remains poorly understood. The development of the Indosinian foreland system remains underappreciated due to few constraints on structural styles, kinematics and ages. Surface cross sections, seismic profiles and detrital zircon data are presented to address the structural styles and evolution of the Indosinian foreland system. The results reveal that the fold‐thrust belt is characterized by fault‐related folds with deeper duplexes and shallower imbricates, which yield a NNE‐SSW regional shortening magnitude of ∼36%. Our new constraints indicate that the Nanpanjiang region experienced multi‐staged thrusting during the Indosinian orogeny (D1). The D11affected the southernmost southern fold‐thrust belt, producing thick‐skinned thrusts involving Neoproterozoic basement and initiating the Nanpanjiang foreland basin. During the D12, NNE‐verging thick‐skinned thrusting continued and was followed by thin‐skinned thrusting in the northern fold‐thrust belt. Locally preserved foreland basin deposits at the northernmost Nanpanjiang Basin define D13. The progressive D14co‐axially deformed the residual basin into a wide and gentle syncline. Thus, the progressive D11to D14deformation sequence of NNE‐verging in‐sequence thrusting and foreland basin migration describe the kinematic and dynamic relationship between fold‐thrust belt and foreland basin during the Indosinian tectonic event. Indosinian D1structures were subsequently refolded by the Yanshanian tectonic event (D2), forming N‐ to NE‐striking cleavage and arcuation of D1fold axes. The Nanpanjiang fold‐thrust belt and its associated foreland basin migrated NNE‐ward during the Middle Triassic to Early JurassicIndosinian deformation produced an orogenic wedge with a thick‐skinned hinterland belt, a thin‐skinned foreland belt and shortening of 36%In‐sequence thrusting and foreland‐propagation (237–186 Ma) led to incorporation of the Nanpanjiang foreland basin into the fold‐thrust belt The Nanpanjiang fold‐thrust belt and its associated foreland basin migrated NNE‐ward during the Middle Triassic to Early Jurassic Indosinian deformation produced an orogenic wedge with a thick‐skinned hinterland belt, a thin‐skinned foreland belt and shortening of 36% In‐sequence thrusting and foreland‐propagation (237–186 Ma) led to incorporation of the Nanpanjiang foreland basin into the fold‐thrust belt