Taking the vertical component as example, this paper analysis the irregularity of rhe daily variation, the amplitude of the daily variations, the values taken at O o＇clock and 12 o＇clock and the menthly mean values, and proposes the standard deviation of the two statiohs and the relationship between the variation amplitude and distance.

For example, when the distance between two stations is 600 km, the standard deviation of daily range difference should be 4r and the variation amplitude of the daily range should be more than 10r. This might cause false seismo-magnetic anomalies to the mobile goemagnetic measurement.

The standard deviation and the variation amplitude at O o＇clock are small, whereas the same parameters are much bigger for thr daily variation amplitude, the 12 o＇clock values and monthly mean values. All of them might cause false seismo-geomagnetic anomalies.

The oblique baseline data show obvious drop started in the first half year of 1974 and opposite change in late 1975. The variation amplitude of Q angzilu baseline data before the earthquake was about 2-3×10-5. There were a slow rise for about three years before the earthquake and a relatively steady trend of Xiaoshuiyi baseline data after the earthquake.

The variation amplitude of Xiaoshuiyi data before the earthquake is about 1-2×10-5. After the data processing the anomalous changes of Qiangzilu and Xiaoshuiyi baseline there existed obviously horizontal movement along related fault before the Tangshan earthquake.

The element content in the fine-grainedfraction ( <0.063mm) of the core is great. The correlation coefficient between the elements in the coarse-grained is high, which indicate that the coarse-grained sediments derived from the same provenance.

The mean value of sandstone and mudstone from SE China appears to be 3. 41 ±1. 22W/m. K and 3. 59±1. 19w/m. K respectively and it varies in a wide range.

The thickness of low-velocity layer in upper-mantal underneath NE China and the belt of transition from Asia to Pacific vary in the rangeof 0-100km and the thickness of the crust in the area is about 30-44km with the changingrange of 14km.

The evident changing rate occures when the pH is equal to 2, the average of α1-2 increases 147.6 percent, the average of c,decreases 57. 1% and 34.8% respectively.

The character of the air bubble oscillations in water is investigated in relation to the initial bubble radius and the fluid pressure variation amplitude.

The position of the maximums of these belts (Lmax = 2.9 and 3.1) coincides with the known dependence of Lmax on the magnetic storm Dst variation amplitude: |Dst|max = 2.75 × 104/Lmax4.

WPIO's maximum volume variation amplitude is 66% larger over the annual mean value.

However, two calculated dδ18O/dT curves display the distinct difference: the variation amplitude of slope series II is larger than that of slope series I.

Daily rainfall data obtained from ECMWF reanalysis are obviously better than those from NCEP reanalysis in terms of long period daily mean, local correlation, variation amplitude, fluctuation pattern and frequency.

A new quantity -maximum correlation time-is introduced to describe thephase relation between the daily variations of the vertical component of geomagnetic field at two stations. The maximum correlation time is computed by using adequate data processing technique from the hourly readings of vertical component at the Peking and Wuhan stations. The mean value of the maximum correlation time is shown to be nearly equal to the difference of local times for these stations. Moreover, it exhibits remarkable seasonal...

A new quantity -maximum correlation time-is introduced to describe thephase relation between the daily variations of the vertical component of geomagnetic field at two stations. The maximum correlation time is computed by using adequate data processing technique from the hourly readings of vertical component at the Peking and Wuhan stations. The mean value of the maximum correlation time is shown to be nearly equal to the difference of local times for these stations. Moreover, it exhibits remarkable seasonal variation which has a period of one year and ranges to about 0.7 hour. Fourier analysis of the maximum correlation time shows that it also conta-ins two appreciable harmonics with periods 29.8 ± 0.6 and 13.7 ± 0.2 days respectively,, and with amplitudes of about 0.06 hour for both harmonics.

Such features as higher stability, quick operation, and convenient maintenance of the proton precession magnetometer in the use of geomagnetic total field measurement make it very suitable to be installed in dense network of geomagnetic observatories or survey sites for monitoring the seismo-magnetic phenomena. But some people propose that it is necessary to measure the geomagnetic component, especially the vertical, to monitor the seismo-magnetic phenomena.In this paper the effectiveness of the total field...

Such features as higher stability, quick operation, and convenient maintenance of the proton precession magnetometer in the use of geomagnetic total field measurement make it very suitable to be installed in dense network of geomagnetic observatories or survey sites for monitoring the seismo-magnetic phenomena. But some people propose that it is necessary to measure the geomagnetic component, especially the vertical, to monitor the seismo-magnetic phenomena.In this paper the effectiveness of the total field measurement in monitoring the seismo-magnetic phenomena is proved on the basis of the formula separating local anomaly origin into external and internal parts. It is shown that the range of anomaly of the total field, △F, can not be zero anywhere in the entire anomalous region and that it is comparable with the range of the component anomalies, △H or △Z. This makes it possible to monitor in seismic region the whole process of the seismo-magnetic phenomena, specially and temporally with a set of dense observatories or survey sites using PPM.

We used the method of ground resistivity measurement to show the variation with time of the earth's electrical resistivity near the surface as the precursor of an earthquake. It has been found that the variation of the resistivity is really very complicated even under conditions of no earthquake and assured accuracy of measurement, thus making the quantitative or even qualitative analysis of the resistivity variation rather difficult.In this paper, the data of variations of earth resistivity observed at a number...

We used the method of ground resistivity measurement to show the variation with time of the earth's electrical resistivity near the surface as the precursor of an earthquake. It has been found that the variation of the resistivity is really very complicated even under conditions of no earthquake and assured accuracy of measurement, thus making the quantitative or even qualitative analysis of the resistivity variation rather difficult.In this paper, the data of variations of earth resistivity observed at a number of stations were analysized for empirical regularities, and on the basis of which a "model of profile section of varying resistivity" was proposed to describe the complex nature and the possible cause of the variation of resistivity in case no earthquake is to occur. From this model section, a formula is obtained for calculating the amplitude of relative apparent annual variation of resistivity at a station characterized by two resistivity layers. Through computations, it is found that, the use of stationary variations of resistivity data might be a possible way to resolve the above difficulty and a concrete method of its application is given.