The basement fractures control environment geochemistry landscape and the features of element distribution,especially the Dingbian-Suide and Huachi-Datong fracture zones divide the Ordos Basin to two completely different landscape section of geochemistry and physiognomy;

The basement fractures control environment geochemistry landscape and the features of element distribution,and especially the Dingbian-Suide and Huachi-Datong fracture zones divide the Ordos Basin into two completely different landscape sections of geochemistry and physiognomy.

It has been pointed out that these measures for water plugging,replugging and well cementing may plug main water productive fractures,control water cut raising,and slow down the production decline.

It is indicated that fractures control on hydrocarbon reservoir formed condition of paleolake evolution,source rock maturation and hydrocarbon distribution,generation,expulsion,migration and accumulation,the relations between paleolake settling,sag filling and rate of fractures forming were studied in the Weixinan sag,Beibu Gulf Basin.

Analysis of three wells in Mazhong Oilfield shows that lithology controls fracture development and fractures control oil-gas distributions under the condition of the same tectonic stress.

Structures or structural belts accompanying with the fractures control the distribution of the gas reservoir, whose main composition is condensate gas.

The stochastic continuum approach obviates the need for detailed information about fracture geometry or assumptions about how individual fractures control flow and transport.

The integration of geomorphology and lineament studies reveal that shallow groundwater occurrence is controlled by geomorphological characteristics whereas faults/fractures control the yield of groundwater at intermediate depths.

He emphasized that current thinking is that faults and fractures control field locations and reservoir quality.

The influences of basic metal chemical composition,heat treatment conditions and welding parameters on the pressure vessel brittle fracture have been investigated.The fracture control analysis of vessel was performed with modern fracture mechanics.Many experimental tests confirmed that the pressure vessels fabricated according to our technical norms are safe and reliable in the service.

The"unsymmetrical effecf"caused by the unsymmetrical explosive loading in a borehole ( for example, extremely eccentric charge and slotted cartridge) is put forward and the influence of the unsymmetrical explosive loading on the initiation,propagation and the final distribution of cracks around the borehole in infinite rock mass is analysed in this paper. It is concluded that the cracks are first generated at the contact place between the charge and the borehole wall, and the rarefaction wave from the propagation...

The"unsymmetrical effecf"caused by the unsymmetrical explosive loading in a borehole ( for example, extremely eccentric charge and slotted cartridge) is put forward and the influence of the unsymmetrical explosive loading on the initiation,propagation and the final distribution of cracks around the borehole in infinite rock mass is analysed in this paper. It is concluded that the cracks are first generated at the contact place between the charge and the borehole wall, and the rarefaction wave from the propagation of the first initiated cracks restrains the initiation and extension of other cracks on the borehole wall, which follows the following necessary conditions:According to the principle of the J-integral, the authors have deduced the theorectical formula concerning the time taken by the initiation of dracks, and the calculated result shows a basical agreement with the dynamic photoelastic experimental result. Finally,the mechanism about the formulation of unsymmetrical loading associated with the slotted cartridg es is analysed, and the application of this new technique in fracture control is mentioned as well.

In this paper, the transient response of a pair of radial cracks which are of equal length and notched symmetrically from a borehole, hole-line-shaped (HLS) crack, is discussed in case of normal tractions being suddenly applied to the wall pf the borehole and the surface of the crack, which comes from the approximatioe of the initiation of the HLS crack under dynamic loading, that is, the first phasn of fracture control.Due to the complexity of the boundary and the existance of the inertia term in the...

In this paper, the transient response of a pair of radial cracks which are of equal length and notched symmetrically from a borehole, hole-line-shaped (HLS) crack, is discussed in case of normal tractions being suddenly applied to the wall pf the borehole and the surface of the crack, which comes from the approximatioe of the initiation of the HLS crack under dynamic loading, that is, the first phasn of fracture control.Due to the complexity of the boundary and the existance of the inertia term in the dynamic equation, neither the integral transform for space veriable nor the conformal mapping can be applied to this kind of problems directly. But from Tweed's work for a crack notched from a circular hole in static case, we can get some inspiration. The problem can be solved by decomposition-superimposition-iteration (DSI)method in the following steps. First the initial-boundary value problem is changed into the boundary value problem by means of Laplace transformation. Next the solution region is decomposed into two simple regions, one is a circular hole, the other is a finite Line-shaped crack.The solutions of the decomposed problems can be obtained by using the separation of variables and the Fourier transform respectively. The displacement and the slress components are derived upon the super-imposition of the solutions. They have satisfied some conditions naturally. Then inserting them into the other conditions, the dual integral equations are obtained,where V(r, p) is a series. The coefficients in it can be determined from the borehole boundary conditions.The unknown function D(aaaaaaaaaaaaaaaaa, p) is included in these coefficients. To solve (1),V(r, p)is regarded as the free term temporarily, the predictor corrector method has been applied here- predicting V(r, p) in ( 1 ) to solve D(α, p), then making use of the borehole conditions to correct V(r, p), the corrected V(r, p) is inserted into ( 1 ) to solve D(α, p) again until the mstable V(t, p) is obtained. Thus ( 1 ) can be reduced to the standard Fredhol integral equation of the second kind.when the radius of the borehole approximates to zero, the equation is identical with Sih's solution for relevant problem of finite line-shaped crack in 1972. The solution of the equation ( 2 ) is got by iteration mentioned above and it leads to the Laplace transforms of the stress components, subsequently they are inverted by a combination of numerical means and an application of the Cagniard-DeHoop inversion technique. It has shown that the space distribution of the singular stress field of the crack discussed here is the same as Sih obtained, while the dynamic stress intensity factor k1,(t) reflects the affecting of the borehole. These are essential information in the application of the current theory of fracture mechnics, The numerical calculations demonstrate the feasibility of the DS1 method and the results provide the quantitative basis for us to simplify the practical problem, and make us fully understand the interaction of wave and the crack in this problem. The inferences from above results are in agreement .with others' experiments. Upon this the reasonable loading method is recommended. Moreover a number of theoretic extensions of the work and the ways to carry out the technique (fracture control) simply and economically in practice are proposed. Among these the most important one is that the DSI method can be extended to study the problem of the HLS crack moving at a constant velocity, which comes from the approximation of the propagation of the HLS crack under dynamic loading.