The application of the method of controlled scratching to study the mechanical properties of rocks

A.V. Nosikov Gazprom Geologorazvedka LLC Tyumen  
K.V. Toropetsky NovosibirskNIPIneft LLC    
B.O. Mikhailov NovosibirskNIPIneft LLC   bmikhailov@nsknipi.ru
P.S. Chernysh NovosibirskNIPIneft LLC    
A.A. Doroshenko Gazprom Geologorazvedka LLC Tyumen a.doroshenko@ggr.gazprom.ru
G.A. Borisov NovosibirskNIPIneft LLC    
The article shows a method for the continuous determination of the elasticstrength properties of rocks by the method of controlled scratching. The created installation allows obtaining information about the resistance to displacement of the indenter, scratching on cylindrical samples of synthetic and natural materials (cores). The developed technique allows to recalculate the values of force obtained by setting the strength of the tensile strength with unlimited uniaxial compression.
Materials and methods
Method of controlled scratching, specialized installation to scratch core samples, results analysis.
Results
The results of a controlled scratching of 1.5 meters of core in 3 penetrations are given. After each drilling, measurements were made of the Brinell hardness coeffi ient in steps of 10 mm. For the determination of UCS by a classical method, nine collections were also selected, consisting of three standard cylindrical samples in each collection (diameter 30 and length 60 mm). All samples of the standard core were selected along the axis of the full-length core (across the natural bedding of rocks).
Conclusions
Scratch test of core makes it possible to increase the detail and accuracy of studying physical and mechanical properties of rocks for constructing one-dimensional geomechanical models. Comparison of obtained detailed profi es of physical and mechanical characteristics with the results of well logging makes it possible to establish reliable correlations during the restoration of synthetic profi es of the elastic-strength properties of rocks along a section. Moreover, the result of profi g the physicomechanical properties over core can serve as a characteristic for the refi of core binding, especially in the most problematic core sampling intervals, for example, folded by halogen-sulfatecarbonate rocks, where the linkage in GK or BK can be ambiguous. In addition to assessing the physical and mechanical properties, the controlled scratching method can be used to mark out a full-length core - to determine the locations for drilling out standard samples in order to obtain maximum information about the object with a minimum number of studies, and also to search for the most homogeneous zones for drilling out the closest samples for construction of the strength passport.
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full-size core scratch test controlled scratching method elastic-strength characteristics profile