Abstrakt
We have studied the geophysical, physical, and geochemical parameters of the Podlesí granites in the western part of the Krušné hory Mts., near the village of Potůčky. The granites represent a fractionated intrusion within the Nejdecký Massif.
In total, the studied well is about 300 m deep with samples collected at depths of between 25 and 110 metres. The method used to specify the deformational characteristics of the rock is based on the experimental loading of the sample with uniaxial strain.
The shear and longitudinal deformation of each sample was measured using a resistive strain gauge (20/120LY41 Hottinger Baldwin Messtechnik) placed directly on a given sample. Intermittent loading of the samples proceeded using a uniform gradient of axial strain of 1 MPa.s-1.
The samples were subjected to five separate loads. During the tests, the following parameters were recorded: stress, longitudinal deformation, and shear deformation.
These data were used to calculate Young's modulus, static Young's modulus, and Poison's ratio. The seismic velocities of P-waves and S-waves were measured using ultrasound scanning.
Both dry natural and water saturated samples were analysed. The ultrasound scanning system consisted of 4 piezoelectric sensors, 4 ultrasonic pulsar receivers, and a digital oscilloscope recorder.
The wave frequency was 1 MHz. The velocities of the P-waves vary from 4580 m.s-1 to 6145 m.s-1.
The velocities of the S-waves vary from 2950 m.s-1 to 3750 m.s-1. These velocities generally increase with the depth down the well.
These data were also used for the calculation of Young's modulus and Poison's ratio number.