Cấu trúc địa chất sâu khu vực trũng sâu biển đông và lân cận theo tài liệu địa vật lý

Ca chn
a v

Tr

i hc Khoa hc T 
LuVa cu: 60 44 15
ng dn: TS. 
o v: 2012

Deep geological structure of the deep basin of the East Sea and adjacent based on geophysics
data
59 tr.
Abstract. Ta cht - a va cht kin to khu
vt s 
c c s d          

n; Gii vi vt th hai chi d liu
 u s d t s kt qu      s
i gi   ng trng l
 i quy gi  tht gnh theo kt qu 
a d ng trng lc; M nh d
t ct ca chu trng lc - a ch
  m b dy tr

Keywords. Va ca cht hc; Bia vu a cht

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ng n
PHƢƠNG PHÁP NGHIÊN CỨU

u ca ch
c   a v     
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   
nghim mt s 
- i: gi  ta
chn, d ng trng l u vi m
di quy tuy
- nh d c
 cu (theo tuyn).
-  Gradient ngang ci vi mnh h tht g
din theo s liu trng lc.
- n theo tuy 
nh nhc bit.
2
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r
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a chn.
2.1. Phƣơng pháp phân tích tƣơng quan
a. Liên hệ tƣơng quan và phƣơng pháp phân tích tƣơng quan
M m biu hi
u m  ca hing t 

H s nh bc sau:




2.2. Phƣơng pháp nâng trƣờng
Tip tc ging th c
t mng th  mt b mt,
  
 suy yu mp t
t ng dng rt to ln
trong thc t

 cp tc gii ng thc th ba ca Green. Theo
ng th
 ca U tm P nc cho b
(2.2)
 n

 c m
2.2.
(2.3)

(2.4)
Vic tip tc gi   ti n
c min tn s lu dng vic tip tc gii


.
Nng th t z = z
0
trong ph rng so vc
ca ngun ti bii Fourier F [U] cu din trong min tn s c
/ / / / / /
00
U(x,y,z ) ( , , ) ( , , )
u
z U x y z x x y y z dx dy

 
 
     


2 2 2 3/2
1
( , , )
2 ( )
u
z
x y z
x y z




  
c bi c hai v c.3) qua min tn s 
p:
(2.5)
Vi F [U
u
i Fourier cp t u cn thi
u din gia F[
u
ng:
(2.6)
t rng: (2.7)
y, vic tip tng th  mt m thc hic
bi s h
(2.7) ry bi vc.
T y rp tiu
dn tt c   |k|  u
  

 i vc tip t.
2.3. Phƣơng pháp Gradient ngang cực đại
 xut b 
ca ngu ng thc hi

H[(, )]=





2
+ 



2
(2.8)

nh Gradient ngang ci: t  
tr Gradient ngang cng ta s  H
m xung quanh theo bng thc:
H



1, < H




,  > H



+ 1, 
H



, 1 < H



,  > H



, + 1
H



1, 1 < H



, > H




+ 1, + 1
H



+ 1, 1 < H



, > H



1, + 1
H



,  2
H



,  








:


=

2

 =
1
2

H



1, 2H



, + H



+ 1, 


b=
1
2


H



+ 1, H



1, 


11
( , , )
2
u
x y z
zr



  

/
0
()
/
0
1
2 , , 0

k z z
e
F z z k
rk







     
uu
F U F U F

















 . 










:
H



 = 

2
+ 

+ H



,  (2.9)


























, 







 , 



















 . 
-nh
2.4. Phƣơng pha
́
p tính đa
̣
o ha
̀
m chuâ
̉
n ho
́

a toa
̀
n phâ
̀
n
       gi      a cht c  
c tng:

G
H
= (2.10)



xz

zz
ng cng trng l 
t ti
:







, 









(2.11)


(2.12)























 


H


H


H



2.5. Giải bài toán ngƣợc đối với vật thể hai chiều.
c  s t b m i,
s  m gia li c




1
0
22
22
1
M
zzxz
zzxz

VV
M
VV
(p) (p)
2
Z (x)=Z (ξ)=b +t ξ+t ξ
p
1p 2p
n
2
(h) qs i lt i
i=1
F= Δg (x )-Δg (x ,h)



i dc theo tuyc ox ly x=d
j
 d
j
c ly sao
cho [d
p
d
p+1
] ca b mt ti c xp x b c t:
(2.13)


 b, t

1
, t
2
   u l
s t v mt m kh
k
ng d
k

t chui c nh
B mt ti  ng trng lc 
i tt c  m 
m
s c:
(2.14)

 u ng trng lc t  hi th j,  
c:

(2.15)
Nu m khc:
(2.16)

Np x=d
j
c ly vi m  
c:
(2.17)
ng ht cnh ct k 
c.

( 2.18)

c s c gii khi cc ti

CƠ SỞ DỮ LIỆU VÀ TƢ LIỆU SỬ DỤNG
1. Cơ sơ
̉
sô
́
liê
̣
u sƣ
̉
du
̣
ng
 lic t kha cha chn s liu ta
i c bii m cp
   tic hin
c ni ngou chnh nhng mt b ranh git
d
j



Δg (x)
i
Δg (x)
j

m-1
j m 0 m
j=1
Δg(x)= Δg (x)+Δg(d ,h ,h ,x)

1
0
j
2 2 2 2
()
g ( ) 2 2
( ) ( )
j
j
d
h
j
j
s d z
d dx
ds
x k k
xx

  


   

  

   
  
1
22
0
22
()
()
( ) ln
()
j
j
d
jj
d
xh
g x k d
xz









(p)
z(ξ)=b +t ξ
p

1
j+1
j
22
d
j
j j 0 j
22
d
0 0 j
(x-ξ) +h
(x-ξ) (x-ξ)
Δg (x)=kσ (x-ξ)ln -2h arctg +2h arctg
(x-ξ) +h h h





cc Kainozoi, Conrad, Moho, h tht ct tng
ha cht-a vu.
Ngun s liu trng lc trong khu vu r
ng bn gc t n kh  o
n s liu kh
c s t b n s liu kh v tinh
v   liu v ng d ng tn d liu trng lc v 
 ng nhng b cao, th hia cht
trong khu v d ng trng l 
chnh  t l  -09-02) v i chi tit tho u ca
  liu trng lc ch yc s d 

 
Nguô
̀
n sô
́
liê
̣
u sƣ
̉
du
̣
ng trong luâ
̣
n văn na
̀
y :
- 



 (

 )  (The General Bathymetric
Chart of the Oceans) 1:200.000
- 

 l 1:1000.000 :
(
- 












1 :200.000 ta ch:

- 





 (



















internet) ta ch:
- 























 /V cruise, 1987, Gagarynsky R/V cruises, 1990-1992 






1:200.000
- 



-  7-10




2007-2008 



c đnh ranh gii ngoi thm lc đa Vit Nam 






1:100.000

 



: 
 1:1000.000 (

















),
(


















) 1:1000.000.

MỘT SỐ KẾT LUẬN VÀ KIẾN NGHỊ
Một số kiến ngh










 i v ca ch


 t s kt lu

+ 





 : 







 (
 3.2g/cm
3
)  (



 2.85g/cm
3
), 













 1016km.  





  i b 





 11
13km, 





Moho n





+ : 





 1828














 (



 2.9g/cm
3
), 






 28








.
+ Ranh gii gi 

 :  (
2.9g/cm
3
) 



(





2.7g/cm
3

) 


















 






 , 



















.
+ : 







 (



2.7g/cm
3

) 
(








3
). 









 . 

0

0
N, 108
0

0

E)  49km. 










 ,  24km. 

























 2









+ 
















 0.53km,
 3km. 









 





.
+ 














 
3
 110km, 


 2-7km, 










2-6km,  (6
0

0
, 108
0

0
) 
3-9km.

+ 













 : 














 ,  (26) 








  mt
Moho 14







 n 3.8

 n
, 












14

?.
Một số kiến ngh:
- Cn tic s lia v   a
v ca chn
- C v c s   
 la ho
-  ca
tr  ng lc, s 
trin cc bi

References
1.  (2003), 


2.  (2000), 





  













, 







, PetroVietnam
3. 

, 24(1), tr. 67 - 80.
4. ng, ,

5.  (2006),  , 














 , NXB








, 
6.  am,

7. 

H

8, tr. 59-63.
8. , 

3, tr. 23-26.
9.            
frommagnetic or gravity Geophysics, 51, 1494 -1498.
10. Grauch V. J. S., L. Cordell (1987), Limitations of determining density or magnetic
     Geophysics,
52, 118-121.
11. Parker, R. L. (1972)       Jeophys. J. Royal

Astr. Soc, 31, pp.447-455.
12. Richard J. Blakely (1995), Potential theory in Gravity and Magnetic Applications,
Cambrige University press, United States of America
13. Wolfgang Jacoby, Peter L. Smilde (2009), Gravity interpretation fundamentals and
application of gravity inversion and geological interpretation, Springer, Verlag Berlin
Heidelberg.
14.    
Techtonophysics, 338, pp. 1-21.