CHINESE JOURNAL OF GEOPHYSICS Vol. 45, No. 6 Nov., 2002 [ ] (2002) [ ] P313 H. Kern T. Popp (, ) (, 24098) [

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1 CHINESE JOURNAL OF GEOPHYSICS Vol. 45, No. 6 Nov., 2002 [ ] (2002) [] P313 H. Kern T. Popp (, ) (, 24098) [ ],,., 19, 3,.,,,.,30 %,. [],,,,. 1,, [1 3 ]., [4,5 ]. [5 ], 0. 5 %,2. 5 %( ) ; 2 %, 9 %( ). ( ) [4 ],.,.,.,.,,.,( ), [6 9 ] [10 12 ] ; ( Q ) [ ] , [ ] ( ) ( ). [ ],,1964,1991,,. E2mail : edu. cn

2 6 : 881 [13,14 ] ; [5,15,16 ],., 19,. 2,V P V S ( ) [4,5 ] : = ( V P ΠV S ) 2-1. (1) 3 () [7,8,13,14 ],. 1MHz, 0. 5 %. 3 1 %. 19, 1., 4. 43mm, h. : X, Y, Z. 1 Table 1 Some parameters of the rock samples Π(g cm 3 ) ( %) B Hornb. 58,Plg. 22,Ep. 16,Bi. 2,Ox. 1 B Py. 37,Plg. 29,Ol. 23,Hornb. 6,Gt. 3,Bi. 2 B Ol. 35,Py. 27,Plg. 20,Gt. 12,Hornb. 4,Bi. 2 B Xeno. 95,Sill. 5 B Py. 83,Hornb. 7,Plg. 5,Bi. 3,Gt. 2 B Qtz. 64,Plg. 18,Fsp. 9,Mu. 5,Oth. 4 B Py. 45,Plg. 44,Gt. 7,Bi. 3,Hornb. 1 B Cpx. 40,Hornb. 30,Opx. 17,Qtz. 5,Gt. 3,Ox. 3,Plg. 2 B Cpx. 58,Gt. 18,Qtz. 15,Bi. 6,Scap. 3 B Ol. 85,Cpx. 6,Opx. 6,Grt. 2,Sp. 1 B Fsp. 30,Plg. 27,Qtz. 21,Bi. 16,Ap. 6 B Fsp. 45,Plg. 23,Qtz. 15,Bi. 14,Ap. 3 B Hornb. 52,Plg. 21,Bi. 14,Ep. 8,Ox. 5

3 882 (Chinese J. Geophys. ) 45 Π(g cm 3 ) ( %) B Gt. 39,Omp. 36,Hornb. 14,Bi. 7,Mu. 4 B Plg. 32,Fsp. 26,Qtz. 16,Gt. 15,Bi. 6,Mu. 5 B Gt. 36,Omp. 33,Hornb. 16,Mu. 9,Bi. 6 B Fsp. 38,Plg. 23,Qtz. 20,Bi. 11,Mu. 5,Hornb. 3 B Ant. 75,Ol. 20,Ox. 4 B Qtz. 70,Plg. 20,Fsp. 10 Ant. : ;Ap. :;Bi. :;Cpx. : ; Ep. :;Fsp. :; Gt. : ; Hornb. : ;Mu. :;Ol. :;Omp. :;Opx. : ;Oth. : ;Ox. :; Plg. :; Py. : ; Qtz. : ;Scap. :;Sill. :;Sp. :;Xeno. : ;Zoi. :.,600MPa, 600MPa min ( 60min) , 1 3 (a) (b) (c) (d) Fig. 1 Changes of V P (a), V S (b), Poisson s ratio (c) and their anisotropy (d) in three orthogonal directions in amphibolite with comfining pressure and temperature

4 6 : 883, MPa,, [7 14 ]. 600MPa 600, [13,, 16 ] ;,,. 1 1MPa [13,16 ],600MPa 600,,,. (1) Table 2 Velocities, Poisson sratios and their anisotropy in three orthogonal directions at several P2T conditions PΠMPa TΠ V PΠ(km s - 1 ) V S Π(km s - 1 ) Π( %) 2 Z Y X Z Y X Z Y X B01 B02 B03 B04 B05 B06 B07 B

5 884 (Chinese J. Geophys. ) 45 PΠMPa TΠ V PΠ(km s - 1 ) V S Π(km s - 1 ) Π( %) 2 Z Y X Z Y X Z Y X B09 B10 B11 B12 B13 B14 B15 B16 B17 B18 B

6 6 : MPa.,,. 2 2, ,,, MPa 19, (A )( A V ), 2. 5 %,2. (2), Fig. 2 Relation between Poisson s ratio s 2. 5 % [5], anisotropy (A ) and P2wave velocity. anisotropy (A V ) in all 19 samples at 600MPa,,. B08 18 %, 9. 4 %;B13 26 %14. 6 %;B01 34 %, %.,B02 B18 B06 B19, : A= 1. 82A V , (2) A,A V, %, %, %,: 3. 2 A= 1. 82A V. (3) 2 2,B02 B %, 11 %; 6. 1 %, 1. 3 %, 2. 5 %,;6. 1 %.

7 886 (Chinese J. Geophys. ) B06 B19. (2,3(a,b) ),, Z, X Y ;, Z X Y,Z X Y, V PX - V P Z. B06 A V = (V PX + V P Z ) 2 = 4. 7 %,B %;, A= Z - X,600MPa B06 ( Z + X )Π %(3(d) ),B %,2. 5 %,., 600MPa 600, (3(e h) ). 3 B06 3 (a) (b) (c)(d) Fig. 3 Changes of V P (a), V S (b), Poisson s ratio (c) and their anisotropy (d) in three orthogonal directions in amphibolite with comfining pressure and temperature in sandstone B06 4, [17] ;(1(c),3(c),4). Z,; X Y,, Z,., [5].,

8 6 : 887 [17,18] Fig. 4 Changes of Poisson s ratio in three orthogonal directions in four samples with comfining pressure [5,17],2. 5 %,. B06 B19,., ; MPa,, (1(d) ). B06 B19,, 200MPa (3(d) ) MPa,,. 600MPa 600,,, [13,16] ;,.

9 888 (Chinese J. Geophys. ) 45,. B08,B13,B01 3,,. ( 7. 38kmΠs) (0. 238) [19],,. B06 B19, ; 3 (B , B ),, ([5]13).,, c c, [20] :c c, 10 %,, 12 %,.,, [20],c,,.,c X,.,. B02 B18,. B02,. B18, [4] [13].,,;,. 5, 3,,.,., MPa,. 600MPa 600,,,., 34 %, %.,.,,,.

10 6 : 889, (3),; ;..,. [ 1 ] Christensen N I, Mooney W D. Seismic velocity structure and composition of the continental crust : A global view. J. Geophys. Res., 1995, 100 : [ 2 ] Birch F. The velocity of compressional waves in rocks to 10 kilobars, 1. J. Geophys. Res., 1960, 65 : [ 3 ] Birch F. The velocity of compressional waves in rocks to 10 kilobars, 2. J. Geophys. Res., 1961, 66 : [ 4 ] Chevrot S, Hilst R D. The Poisson ratio of the Australian crust : geological and geophysical implications. Earth and Planetary Science Letters, 2000, 183 : [ 5 ] Christensen N I. Poisson s ratio and crustal seismology. J. Geophys. Res., 1996, 101 : [ 6 ] Christensen N I. Shear wave velocities in metamorphic rocks at pressure to 10 Kilobars. J. Geophys. Res., 1996, 71 : [ 7 ] Kern H, Wenk H P. Fabric2related velocity anisotropy and shear wave splitting in rocks from Santa Rosa mylonite zone, California. J. Geophys. Res., 1990, 95 : [ 8 ] Barruol G, Kern H. Seismic anisotropy and shear2wave splitting in lower2crustal and upper2crustal rocks from the Ivrea Zone s experimental and calculated data. Phys. Earth Planet. Inter., 1996, 95 : [ 9 ],,.., 1995, 38(2) : MU Run2Chang, GAO Ping, LIU Rou2Xin et al. The experimental study of P2wave velocity anisotropy of mylonite and its surrounding rocks from ductile shear zones of North2China at elevated pressures and temperatures. Chinese J. Geophys. ( Acta Geophysica Sinica), 1995, 38(2) : [10] Siegesmund S, Takeshita T, Kern H. Anisotropy of V P and V S in an amphibolite of the deeper crust and its relationship to the mineralogical and textual characteristics of the rock. Tectonophysics, 1989, 157(1) : [11],JI Shao2Cheng,..,1994,37(4) : JIN Zhen2Min, JI Shao2Cheng,JIN Shu2Yan. Lattice preferred orientation of olivines and seimic anisotropy in the upper mantle. Chinese J. Geophys. (Acta Geophysica Sinica), 1994, 37(4) : [12],Mainprice D..,1989,11(4) : JI Shao2Cheng, Mainprice D. Seismic anisotropy in the lower crust induced by the lattice preferred orientations of minerals. ology and Geology (in Chinese), 1989,11(4) : [13],,Kern H.., 1998, 41(3) : LIU Bin, GE Ning2Jie, Kern H, et al. Velocities and attenuation of P2and S2waves and their anisotropies in serpentinite and amphibolite under different P2T conditions. Chinese J. Geophys., 1998, 41(3) : [14] Kern H, Liu B, Popp T. Relationship between anisotropy of P2and S2wave velocities and anisotropy of attenuation in serpentinite and amphibolite. J. Geophys. Res., 1997, 102 : [15] Kern H. Elastic2wave velocity in crustal and mantle rocks at high pressure and temperature : The role of the high2low quartz transition and of dehydration reactions. Phys. Earth Planet. Inter., 1982, 29 : [16] Kern H, Richter A. Temperature derivatives of compressional and shear wave velocities in crustal and mantle rocks at 6 kbar confining Seism2

11 890 (Chinese J. Geophys. ) 45 pressure. J. Geophys., 1981, 49 : [17] Wenk H2R. Preferred Orientation in Deformed Metals and Rocks : An Introduction to Modern Texture Analysis. New York : Academic Press, Inc., [18] Duba A G, Abey A E, Bonner B P, et al. High pressure mechanical properties of Kayenta sandstone. Univ. Of California, Lawrence Livermore Lab. Rept., 1974, UCRL : [19].. :,1976, Physical Properties of Rocks and Minerals. M o scow:deepearth, [20] Auld B A. Acoustic Fields and Waves in Solids. John Wiley, ANISOTROPY OF POISSON S RATIO IN ROCK SAMPLES UNDER CONFINING PRESSURES LIU BIN XI DAO2YING GE NING2J IE WANG BAO2SHAN ( School of Earth and Space Sci, Uni. of Sci. and Tech. of China, Hefei , China) H. KERN T. POPP ( Geowissenshaften Institut, Uni. Kiel, Kiel, Germany) [Abstract ] Poisson s ratios calculated from V P ΠV S can provide much tighter constraints on the crustal composition than either the compressional or the shear velocity alone. To study the changes of Poisson s ratio and its anisotropy with confining pressure, we measured P2and S2wave velocities in three orthogonal directions in 19 rock samples under different confining pressures. The results show that, in most samples there are some linear correlation between Poisson s ratio anisotropy and P2wave velocity anisotropy ; while in some samples there are no significant correlation between them; some samples even show totally opposite changes in Poisson s ratio anisotropy and P2wave velocity anisotropy. Since in most rock samples Poisson s ratio is very markedly anisotropic, some even greater than 30 % when the effect of microcracks is eliminated, the anisotopy of Poisson s ratio must be considered when using Poisson s ratio to inverse the crustal structure. [ Key words] Confining pressure, Ultrasonic wave velocity, Poisson s ratio, Anisotropy, Inverse.

1.0 % 0.25 % 85μm % U416 Sulfate expansion deformation law and mechanism of cement stabilized macadam base of saline areas in Xinjiang Song

1.0 % 0.25 % 85μm % U416 Sulfate expansion deformation law and mechanism of cement stabilized macadam base of saline areas in Xinjiang Song 1.0 % 0.25 % 85μm 0.97 0.136 % U416 Sulfate expansion deformation law and mechanism of cement stabilized macadam base of saline areas in Xinjiang Song Liang 1,2 Wang Xuan-cang 1 1 School of Highway, Chang