Cấu trúc và tiến hoá địa chất vùng bãi bồi ven biển nghĩa hưng tuyển tập tài nguyên và môi trường biển, tập 10, tr 89 105

•

X dVl
--

cbaZYXWVUTSRQPONMLKJIHGFEDCBA

N 3
~1H D N O
, flH ~

lOv,W

N 3v A f l D N I V ~
,
•

dVl
-- N3AfU
~

VA


V ltN

K H O A H Q C v A C O N G N G H t v ItT
V I~ N

HAl DUONG

,,?

NAM

HQC·

"

TUYENTAP
ONMLKJIHGFEDCBA
. cbaZYXWVUTSRQPONMLKJIHGFEDCBA

TArNG'UYEN
"'

A

...••.

~

VA MOl TRUONG BIEN
T~PX

B a n b ie n t~ p :
T ru d n g

P G S ., T S . N guyen

ban:

'I'h tr k y :

V an T i~ n

T S . N g u y en

H uy Y ~t

T S . N guyen

D ue C u

T S . N guyen

H uu C li

C a c tb a n h v ie rn

T S . L uu V an D i~ u
T S . T rlln D ue T h~ nh
T S . D b C ong T hung

M
N H A X U A T B A N K H O A H Q C vA lIT T H U A T
H A N or - 2003


T , N H ;,
r e s u lt s

of

± 7 .1 4 % ,
,C d ,

MVC Ll)C

A s,

± 0 .5 1

T ran g

-

L ei n 6 i d fiu

3

k d e s ig n ,

1 . 4 5 n arn h o at d o n g v a p h at tri~ n cu a P h an v ien H ai d u o n g h 9 C tai H ai
P h o n g (1 9 5 9 - 2 0 0 4 )

~ Q A /Q C

N g u y in

la r e h ig h t

2 . C o astal E ro sio n an d S ed im en tatio n

5

V a n T ie n .

in V ietn am

20

T r a n D u e T h a n h , P h a m H u y T ie n ,
B ui H ong Long, N guyen V an C u

3 . R esearch es in E stu arin e E n v iro n m en t
O v erv iew o n A ctiv ities an d R esu lts

an d E co sy stem

o f R ed R iv er: A n

34

T r a n D u e T h a n h cbaZYXWVUTSRQPONM

4 . G eo lo g ical E n v iro n m en t

o f th e T ien y en - H aco i B ay

54

N guyen H uu C u, N guyen N goe, T ran D ue T hanh,
D in h V a n H u y , N g u y e n Q u a n g T u a n ,
N guyen V u Tuan,

N guyen Thi P huong H oa,

N g u y e n T h i K im A n h , D a n g H o a i N h o n

5 . S tu d ies o n S eaw eed s

in V ietn am

67
N g u y e n V a n T ie n , N g u y e n H u u D a i

6 . R esearch es

in D istrib u tio n

o f V ietn am ese

S eag rasses

76
N g u y e n V a n T ie n

7 . C au tru e v a tie'n h o a d ia ch at v u n g b ai b 6 i y en b i~ n N g h ia H u n g
N g u y e n . H iiu C ll, T r titi D u e T h a n h , N g u y e n .
Q u a n g T u r in , D iin g

N g u y in

N g u y in

T h i K im A n h , B u i

89

va

T u r in ,

Hoai Nhan,
V a n Yumig

8 . D ac tru n g h in h th ai - d o n g lu c v a b ien d an g b o H ai H au , N am D in h

Dinh.

106

V a n H u y , D 6 D in h C h ie n ,

T r iin .D u e T h a n h , B u i V a n V z i< ;J n g

9 . M o t su u t?-p h o a th ach tru n g 16 ( F o r a m i n i f e r a ) M io x en m u o n it d u o c b iet
d e'n ONMLKJIHGFEDCBA
d k h u Y I;iCb 6 n tram tich D ~ tam y en b i~ n D 6 n g H d i (Q u an g B in h )
N g u y in N g o c , N g u y in

Hiiu

126

C ll

1 0 . B u d c d fiu d an h g ia tac d o n g cu a h 6 H o a B in h d 6 i v d i n g u o n lei ca b i~ n
y en b o

139

T r t i n . D u e T h C J - n hD, 8 D i n h C h i e n

1 1 . K h a n an g tac d e)n g cu a m o t so ' h in h th irc n u o i th u y san d e'n m 6 i tru o n g
v u n g b i~ n y en b o H ai P h o n g

161

L u u V a n D ie u

, 1 2 . H ien tran g , x u th e' b ien d 6 i m o i tru o n g d ia h o a tram tich d fim n u 6 i t~ i

171

v u n g y en b i~ n H ai P h o n g
N g u y in

Thi Thu

nu«

N g u y in

1 3 . M o t so ' d § .n lieu v g an h h u o n g cu a cac m uoi d in h d u d n g ( P 0 4
v d i m at d e) te' b ao q u an x ii th u c v at p h u d u tai v in h H ~ L o n g
N g u y in

T h i M i n h Huyen, C h u V a n T h u o c ,

3

D ue C u

-,

N O ;) d 6 i

va

Thi Luu

182

349


1
T u y e " n U jp T a i n g u y e n . v a M 6 i tr u a n g

b iln .

T i i p fedcbaZYXWVU
X

CAU TRUC VA TIEN HOAwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIH
f)~A CHAT
"

_

A '

,,:J

_

VUNG BAI BOI VEN BIEN NGHIA HUNG
N g u y in
IN g u y in

H i t u WVUTSRQPONMLKJIHGFEDCBA
C a , T r iin . D u e T h q ,n h ,

V u T u a n l,

N g u y in

D ij,n g H o a t N h a n , N g u y in

.

Q uang
T h ! K im
Bui

Van

rc s-;
Anh,
V U !1 n g

1. MO DAD
Huyeri Nghia Hung, dia phan cue nam cua tinh Nam Dinh, narn giua song
Ninh Co (d phia dong bac) va song Day (d phia tay nam), co vung bai b6i ven bi~n
rong IOn. La bQ phan cau true quan trong cua vung cua Lai Giang (cira song Ninh
Co) va vung cua Day, bai b6i nay co tiern nang to IOn ph at tri~n kinh te - xa hQi
khu vue. Vung cua Day va vung cua Ba Lat Ia hai vung cira song co bai b6i IOn
nhat va toc dQ b6i Ian ve phia bi~n cling IOn nhat cua chau th6 song Hting hien
dai. Theo dong lich slt chinh phuc vung dat mdi, cac bai b6i chau th6 song H6ng
luon la doi tuong khai hoang, chiern cu qua nhieu the h~ lam noi sinh va tao dung
cac co sd san xuat nong nghiep, ngu nghiep hay diem nghiep. Huyen Nghia Hung
cling co lich slt khai hoang Ian bien lau ddi va nhu cau slt dung bai b6i ven bi~n
van tiep tuc gia tang. Tuy nhien, slt dung hop ly cac bai b6i d~ cho hieu qua kinh
te cao dang thach thuc moi n6 luc khao sat, nghien cuu ban chat tv nhien va
danh gia tiern nang Slt dung. D~ gap them co sd khoa hoc cho dinh huang slt dung
hop ly bai b6i ven bi~n Nghia Hung, bai viet nay cung cap tu lieu cu th~ ve thanh
phan va cau true tr:1m tich, danh gia dQng luc phat trien va tien hoa moi trucng
tram tich vung bai b6i ven bi~n va dUQChoan thanh voi su h6 tro cua HQi d6ng
Khoa h9C tv nhien narn 2003.

2.

c o s o T A l LI~D v A
Tai lieu chu

yeu

P H U 'd N G

PHAp

d~ xay dung bai viet nay la ket qua nghien cuu cua Phan

vien Hai duong h9C tai Hai Phong trong thoi gian 2000 - 2003 [2, 3, 6, 7, 8] thuoc

89ZYXWVUTSRQPO


t g p WVUTSRQPONMLKJIHGFEDCBA
T 'a i n g u y e n v a M 6 i t r u o n g
b iin .

T u y in

cac de tai khac nhau

T tip X

ma cac tac gia dil true tiep tham

gia. Tren co sa phuong

phap luan tiep can h~ thong dong luc moi truong dia chat, khu vue nghien cuu
duoc xem la mot bi? phan cau thanh

chau th6 song Hong hien dai noi chung hay

cua vung cua song Ninh Co - cua Day noi rieng.

3. T H A N H

PH A N vA

C A U T R U C T R A M T ic H

bo

1 . 1 . T h a n h wvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
phan cd hoc t r i i m t i c h fedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
v a phan
ZYXWVUTSRQPONMLKJIHGFEDCBA

Tram tich tang mat bai b6i va suon bo ngarn bao g6m: cat nho, bot ldn, bun
bot nho va bun set bi?t (hinh 1).
Cat nho co duong kinh trung binh

- Cat nho.

mm, chon 19C tot vdi di? chon 19C

(S o )

trong khoang 0,102 - 0,131

(M d )

trong khoang

1,250 - 1,592 va di? lech

trong khoang 0,791 - 1,000. Cat nho co mau xarn, l§.n mica va manh

(S k )

voi va

Y I;m

sinh vat (chu yeu la Than mern), phan bo lien tuc tu cua Lai Giang (Nghia Phuc)
qua C6n Vinh, C6n Xanh va C6n Mo toi tan cua Day a khoang di? cao tir duoi Om
hai d6 tdi tren muc biJn trung binh. a dudi suon bo ngam tdi di? sau 2 - 3m, cat
nho ciing xu at hien thanh cac dai nho, hep khong lien tuc va song song vdi duong
be.

•

BOt

Ia n .

Bot IOn co duong

0,058 - 0,095 mm, chon 19C tuong
1,262 - 1,930 va di? lech

Sk

kinh

trung

binh

Md

trong

doi tot vdi di? chon 19C

SO

khoang
trong

rong

khoang

trong khoang 0,212 - 1,096. Bot IOn co mau xarn nau,

doi ch6 l§.n va voi sinh vat, co dien phan bo IOn thu hai sau bun bot nho, tao
thanh dai lien tuc tu cua Lai Giang bao quanh C6n Xanh, C6n Mo tdi cua Day, a
khoang di? sau 1 - 2m tdi di? cao muc biJn trung binh.

o

nhieu ch6, bi?t IOn tao

thanh be mat tuong doi bang phang, rat thuan loi cho nuoi Ngao .
•

Bun

trung binh

bO t
Md

nho.

Bun bi?t nho mau nau do, tuong doi deo, co duong' kinh hat

trong khoang 0,015 - 0,047 mm, chon 19C tir tot tdi trung binh

di? chon 19C trong khoang

1,151 - 3,159 va di? lech

Sk

Bun bi?t nho co dien phan bo IOn nhat nhung chu
trung binh tao thanh

vdi

trong khoang 0,604 - 1,528.
yeu

a di? cao tren muc biJn

bai tr ieu cao tU de N am Dien tci glin C6n Mo, a long song

Day va suon bd ngam phia ngoai.

o bai

tr ieu cao, loai tram tich nay dang tham

gia vao qua trinh lay hoa vdi vai tro quan trong cua thuc vat ngap man .
•

Bun

set

trong khoang

b o t.

Bun set bot mau nau do, deo co duong kinh trung binh

0,009 - 0,010 mm, chon

khoang 2,434 - 3,315 va di? lech

Sk

19C trung

binh

vdi di? chon 19C

SO

Md

hong

trong khoang 0,728 - 1,645. Bun set bot co kich

thuoc g:in vdi gidi han cap hat cua tram tich bun bot nho va co dien phan bo rat
90


T u y ln

nho d long song Day va nhu v~y

it

tijp

rat

nguyen

v a M 6 i tr u e in g b iln .

T ijp

X

co y nghia ph an anh tinh ph an di cua tram

tich.
C H U G IA I

1 • Cat nho,

2 - B 9 t Io n .

4 - V i tri 1 6 k h o a n

5 - Oui1ng

0,0 m h a i d o ,

1200

Om

1 ..1
_ .:...

3 - Bun b9t nhc

ta y , s o h i~ u v a

••••' _

m at

dt

X a N g h ia P h u c

6 - D e , bo d a m

1200
••••• _ ,

X a N a m wvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
Oi€ln ZYXWVUTSRQPONMLKJIHGFEDCBA

;.,
o

;.,

o
19'50'15"

H in h

'_-

19°50'15"

1. So d6 ph an

bo tnim tich tl'lng m(lt vu ng biii b6i ven bi~n Nghia Hung

3.2. Thanh ph an khoang v~t nang trong tr~m tich
Thanh

phan

khoang

vat

nang

da duoc phan

tich

trong

hai

cap hat

0,063 - O,lmm va 0,1 - 0,2 mm. Trong tram tich chua khoang vat nang, hai cap
hat nay lucri chiern ty trong cao nhat va la co Sd dJ danh gia ham luong khoang

91


Tuyin tgpZYXWVUTSRQPONMLKJIHGFEDCBA
T a i n g u y e n . va M6i t r WVUTSRQPONMLKJIHGFEDCBA
u i r n g bien. T t i p A
x wvutsrqponmlkjihgfedcbaZYXWVUTSRQPO

vat nang trong

tcan

xac dinh

khoang

manh

trong

vun

khoang

sat

nhat,

0,01 - 0,85%, trong

oxyt, khoang

vat nang

hrong. Trong

mau. T6ng ham luong khoang

thucng

cap hat

a

dat 0,85%.

vat ilmenit,

cao trong

vat nang

trong

do chu y e u la khoang

hocblen

cap hat

va manhetit.

vat amphibol,

T6ng

siren bo ngarn yen C6n Mo, ham

luong
luong

khoang
khoang

luong

ham

0,3% trong

bot Ion va cat nho, tren

bot Ion yen bo song Day, ham

tich duoc

tram

vat nang
vat nang

Ion
cling

dat 0,51 %.
3 .3 . C a u t r u e t r c lm t ie h

Cau true

mat tram

tich vung bib b6i yen bi~n Nghia

bao b9C, cau tao bang' tram
tram
hat

tich hat
tho hen

tich hat

ngoai

dac trung

duoc thanh

tao chu yeu do s6ng,

chu y e u duoc thanh

tho hen bao ngoai

hinh

dang

tao do dong chay,

lien tuc noi lign hai lach cua Day va cua Lai Giang.
phan

anh su hinh

b6i tich vg phia
boi xu the phat

thanh

lien quan

tay nam.
tri~n

- Tudng bai (beach),
doi trigu,

tram
khong

cau

tram

- Tucng

tich nay c6 hinh

di~n hinh,

tao hinh

cung
trong,

va di chuyen

cung bat doi xung

tao bang

cau tao bang cat nho.

"

cat nho, bot ldn, tao

bai trieu

thanh

doi cat trieu

len 6 phia cua Day.

tich nay tao nen th~ tram

- Tudng bai tr ieu thap,

nho dong trieu

c6 th~ tram

Day la dac di~m quan

x6i 16 be Hai Hau

doi

tich sau:

xuong 6 phia cua Lai Giang va doi trieu
Hai tudng

tucng

tich

keo dai vg phia tay nam va ep Iuong cua Day. Cau true mat,

vung bai b6i g6m cac tudng

- Tudng

toi qua trinh

Hen nira, th~ tram

n6 la

cua Ba Lat c6 cac th~ tram

thang' va song song vdi duong be, b vung bai b6i yen bi~n N ghia Hung
tich hat

bbi bd

tho hon (cat nho, bot Ion), ben trong

nho (bun bot nho). Khac vci vung

phia

Hung

tich bao ngoai vung bai boi.

g6m chu y e u la bot lon, it cat nho.

cao (bai l~y), g6m chu yeu la tram

len va dang trong

qua trinh

tich bun b(>t nho tich tv

l~y hoa vdi vai tro cua thuc vat ngap

man.
Theo chieu th~ng
phan

d(> hat

va mau

cac ldp nay khong
phan

di theo khorig

dung,

c6 th~ ghi nhan

sllc nhung

khong

6 lop tram

lien tuc trong

ngu y ph an anh thoi dia t~ng
gian bg mat thong

tich khac nhau

mot mat cat.

ma la thach

qua 9 mat cat 16 khoan.

81,l'

vg thanh
ph an biet

dia t~ng va tudng

Cac lop nay bao

g6m bun b(>t nho mau nau; bun set bot mau nau xam, deo; cat nho mau xarn; bun
bot nho mau nau xam, deo; bun bot nho mau xarn, deo va bot ldn mau xarn, trong
do lop bot Ion mau

xarn narn 16t day la ph6 bien trong

th~ cac mat cat 16 khoan

92

nhu sau (hinh 2).

cac mat dt

16 khoan.

Cu


T u y e n . tg p

/0

• M ?t cat

khoan

NH

san sat bo song Day phia

1. L6 khoan

tay bai b6i Nam

0,0 m luc d6. Mat d.t

0,6m/ tren

mau nau vdi duong
lech (S k ) 0,854.
khoang

- LK

0,15

kinh

trung

Lop duci

- 0,19

Tai

nay duoc khoan

Dien.

binh

(M d )

S o trong

su«.

t r WVUTSRQPONMLKJIHGFED
u in ig
T g p fedcbaZYXWVUT
X

trong

darn nuoi thuy

D9 sau C9t khoan

g6m 2 lop. Lop tren

(0,4 - 1,25m)

mm.

nguyen. va M 6i

1,25m,

(0 - 0,4m)

Ia bun

0,016 mm, d9 chon 19c

la bun bot nho mau

khoang

1,837

- 2,160

nau

d9 cao
bot nho

2,352 va d9

(S o )

xarn co M " trong

va S ;

trong

khcang

0,861 - 1,000.
• M ?t

de Nam
tuorig

Dien.

2,193

khoan

NH

- LKl.

Lop tren

(chon 19C trung

bot nho rnau

nau

xam,

/0

de Nam Dien co thuc
ldp. Lop tre n

binh)

nau

co

xarn,

deo,

binh)

NH -

LK3.

vat ngap

(0 - 0,3m)

(chon 19C trung

(0,0 - 0,4m)

=

=

va S k

0,026

=

Md

va S k

=

d.t

cung

mm

san ngoai

g6m hai lop

=

0,024

(0,4 - 1,25m)

(tho hen

mm,

la bun

ldp tren),

So

=

0,533 - 0,918 .
duoc thuc hien

tren

bai b6i cao ngoai

sau 1,15 m va cao d9 0,7 m. Mat cat g6m ba

bot nho mau

0,826.

nau,

co

=

Md

0,015

mm, S o

=

2,680

Lop giira (0,3 - 0,6 mm) la bun bot nho mau

mm,

S o = 2,195

v a S k = 0,996.

(0,6 - 1,15m) la bun b9t nho mau nau xam, deo, co

s.

Mat

Lop duoi

- 0,047

L6 khoan

man,

la bun

0,030

darn nuoi thuy

bot nho co M "

la bun

va S k = 1,000.

deo, co M "

khoan

nam trong

1,25 m, cao d9 0,4m.

binh)

2,101 - 2,250 (chon 19Ctrung
• M ?t cat

L6 khoan

- LK2.

D9 sau C9t khoan

tu NH

=

So

/0

cat

Md

=

0,030

Lop

duci

cung

=

2,353 va

thanh

cac ldp

mm, S o

= 0,888.
Ca ba mat cat tren

nho mau
chua

sAc. Dieu

xac thuc

dang

vat ngap

deu la tdm

tich bun bot nho, ph an biet

luu y la hat

tram

man,

mot pha lap d~y va khong

•

M ?t

/0

cat

khoan

chung

tich tho d~n tu tren

to tram

tich nay duoc lang' dong trong

co vai tro cua thuc vat ngap
NH

- LK4.

sau 1,95m va cao d9 khoang

Dien,

Lop tren

(0,0-0,4m)

la bun bot nho mau nau,

19Ctrung

binh

M d = 0,057

- 0,070

=

0,786.

M ?t

Nghia

/0

cat

mm, S o = 1,323 - 2,276,

Hung,

sau

khoan

1,25m,

NH

- LK5.

(0,4 - 0,9m)

S o = 2,216

S k = 0,436

L6 khoan

cao d9 khoang

Ia bun

=

0,026 mm, S o

g6m hai lop.

=

3,060 (chon

Ia bot IOn m a u

- 1,000.

man

xarn co

6 mot sO'·m a t dt

Sd.

(0,0 - O,4m) la bun bot nho m a u n a u co
Lop giiia

Md

vat ngap

0,7m. Mat dt

Lop duoi (0,40- 1,95m)

khac, lop bot IOn nay duoc coi 1a ldp co
•

co

cung

man,

d bai b6i cao co thuc

L6 khoan

phia ngoai de Nam

kern) va S k

xuong va khong

Md

bot nho mau

d trung

tam

0, 7m. Mat
= 0,012

nau

vung bai b6i ven bi~n

cAt g6m

ba

ldp. Lop tren

mm, S o = 2,203 v a S k = 0,926.

xarn co M, = 0,014

- 0,025

mm,

- 2,339 v a S k = 0,817 - 0,979. Lop dudi c u n g (0,9 - 1,25m) la bot IOn m a u

xarn, co M d = 0,058 mm, S o = 2,142 v a S k = 5,18 .
•

M ?t cat

/0

khoan

NH

- LK6.

L6 khoan

d trung

tam vung bai b6i, sau 1,15m,

93 ZYXWVUTSRQ


T u y in

tijp

T a i n g u y e n . v a M 6 i tr u im g

co cao d9 khoang

T i j p fedcbaZYXWVUTSRQPONMLKJIHGFEDC
X wvutsrqponmlkjihgfedcbaZYXWVUTSRQ

b iin .

Mat cat cling g6m ba ldp tuong tu NH - LK5. Lop tren

0,8m.

(0,0 - 0,3m) la bun bot nho m a u

nau co

=

Md

0,020 mm, S o

=

Lop giua (0,3 - 0,8m) la bun bot nho mau nau xam co M d

=

Sk

0,863.

mm, S o
•

=

M t jt c a t

/0

=

mau nau co M "

=

NH

S k=

- LK8.

Mat dt

L6 khoan

xarn voi

d bai b6i phia ngoai g:in C6n Me, sau

g6m ba lop. Lop tren

=
So =

0,15 mm, S o = 1,278 va S k

set bot mau nau xarn co M d
(0,6 - 1,25m)

0,027 mm,

0,537 .WVUTSRQPONMLKJIHGFEDCBA

khoan

1,25m, cao d9 0,75m.

= 0,863.
S o = 2,475,

Md = 0,056

2,477 va S k

(0,8 - 1,15m) la bot ldn mau nau

Lop dudi cung

1,974 va S ;

=

=

0,009 mm,

Ia bun b9t nho

(0,0 - 0,5m)

0,844. Lop giiia (0,5 - 0,6m) la bun
3,315 va S k

la bun bot nho mau nau xarn vdi Md

=

=

1,645. Lop duoi cung

0,033

=

mm, S o

2,887

va

0,708.

120
N H -L K 4

N H -L K 3

N H -L K S

C H U G IA I

60

-

-:::'

40

f------j

__

1 - Bun

b o t n h o rn a u

23-

s ~ t b o t rn a u

Bun

nau, It d e o
nau x a rn , de o

C a t n h o rn a u x a rn

4 - B u n b o t n h o rn a u n a u x a rn , de o

5 -

4

Bun

b ~ t n h o m a u x a rn , c le o

6 - B o t Ia n rnau xarn

mblb

.

oem

-

-

mire

/'

6

40

Ty

Cao do

5

Ie d U n g :

1: 25

10

tin h

khoan

b i~ n tru n g

b in h

th e o
(m b tb )

/'
/'

/'

80

120
140
120
N H -L K 6

N H -L K Z

N H -L K 6

N H 'L K t

80

4
m b tb

''::

I

40

-

-

4

/

/

. - '-

6\.

. . .

.

. .

.

...........

z

oem

/

.....
[J
.

~ .....

40

N H -L K 9

.

.

4
\.

" -, ,

I

ao

/
I

120
140

H in h

94

2. M~t ciit 16 khoan vung bal b6i ven bi~n Nghia Hirng

3

.


T u y in

tifp T a i n g u y e n

v a M 6 i tr u a n g

b iin .

T i f p fedcbaZYXWVU
X

S\J c6 mat lOp bun set bot day O,lm la rat cue b9, c6 duorig kinh hat trung
binh IOn glin vdi gioi han bun bot nho, chon lee kern va d9 Iech IOn nghieng
hat IOn hon 0,01 mm. V?y trong

qua trinh

ve cap

tich tu, su bien d9ng tuc thoi cua moi

truong tram tich cimg c6 th~ t1;1.0nen tram tich dang thau kinh

c6 vat lieu tho

hoac min hon la dieu binh thuong.WVUTSRQPONMLKJIHGFEDCBA
•

0,65m.

M ?t cat

Mat

/0

d.t

khoan

chi g6m

NH - LK7. Cat nho c6
va S k

=

NH

Md

- LK9.

cat

=

Lo khoan d phia tay C6n Me, sau 0,5m, cao d9

nho

xarn,

mau

tuong

doi chat,

0,128 - 0,136 mm, chon 1Qctot vdi

tuong tu nhu

So

=

1,224 - 1,258

1,000.A

"

,

,,? ...,..,

,,,

...

4. DQNG Ll)'C PHAT TRIEN VA TIEN HOA MOl TRUONG
TRAM

rtca

4.1. V! tri dlu true vurrg bai b6i ven bi€n Ngh ia Hung
Vung bai b6i ven bi~n Nam Nghia

Hung la mot b9 phan

Hong hien dai tU D6 Son tdi L1;1.chT ruong

(rong khoang

cua chau

th6 song

6 500 krn"), c6 nguon nuoi

b6i tich true tiep tu song Day va song Ninh Co. Cua Day va cua Ba L1;1.tla 2 cua
IOn nhat trong so cac cua lon, g6m cua Van

vc,

cira Thai Binh, cua Diem H9, cua

Tra Ly, cira Lan, cua Ba L1;1.t,cua L1;1.iGiang, cua Day va cua L1;1.chTruong' (khcng
k~ bon cua nho - cua Hong, cua So, cua Ha Lan va cua Can).
Trong qua trinh

phat

tri~n doi bo chau th6 song Hong hien dai, vai tro IOn

nhat Ia cua Ba L1;1.t,thu hai la cua Day, thu ba la cua Van
LY. Cac clia can lai c6 vai tro khong

vc,

dang k~. LUQng phu sa hang nam

Day la 19,312 tr ieu tan v a qua cua L1;1.iGiang 2, 577 trieu
chau th6 song Hdng n6i chung,

thu tu la cua Tra

tan

qua cua

[7, 8]. Doi vdi bo

vai tro cua hai cua song nay rat chenh

lech, song

doi voi vung bib b6i ven bi~n Nghia Hung, moi cua c6 vai tro quan trong rieng, va
dac biet can c6 vai tro cua d01;1.nb d Hai Hau do bi x6i Id va mat b6i tich di chuyen

ve phia tay nam.
Cha u th6 song H6ng la mot bon tich tu ven be quy mo ldn, di~n hinh ve ki~u

101;1.i
va cau true, ph at tri~n lien tuc tren nen sut h1;1.tan kien t1;1.0v a kien t1;1.0h ien
dai, Tuy nhien, che d9 sut

h1;1.nay phan

di phuc

t1;1.Pca ve cuong

d9 va xu the,

tharn chi can t1;1.0n en ca ddi nang noi vong.
Dong bang

song Hong ph at tri~n tren

cac ddi kien

true

nhau ve tu6i va phuc h~ vat chat, trong d6 khu vue nghien
kien

true

c6 va luc dia hinh thanh

mafic thuoc
carbonat

h~ tling Vien Nam

thuoc h~ tang

vao Trias

(T1vn), thanh

muon

co va luc dia khac
cuu nam

vdi cac thanh

tao vun

luc nguyen,

trong ddi

t1;1.0p hun trao
luc nguyen-

Co Noi (Tjcn), h~ tling D6ng Giao (T 2a dg), thanh

t1;1.0
tram

95 ZYXWVUTSRQP


T u y e " n tijp T a i

tich -phun

Suoi

nguyen

trao

Bang

va M 6i

sb). Trong

nghien cuu phat tri~n
dong

b:1c vdi bien

X wvutsrqponmlkjihgfedcbaZYXWVUTSRQPONM

b ie " n . T iip

h~ tang Song Boi (T2.3sb) hay thanh tao molat

thuoc

(T',n-r

tr u a n g

giai

dean

tan

kien

va kien tao

tao

thuoc

h~ tang

dai, vung

hien

tren ddi nang yeu gidi han bdi dirt g§'y song Day i':Iphia

di? tren

dudi 300m

(Nguyen

Cl1n, 1989,

Nguyen

Cl1n va nnk,

1996 [7]).
Trong
dai,

cau true

vung

bai

ngang

b6i yen

dia chat

moi truong

bi~n

Nghia

Hung

doi be chau th6

(k~ ca Kim

Son)

song

thuoc

Hong

phu

hien

ki~u

moi

truong dia chat bai b6i chau th6, noi dien ra qua trinh b6i tu Ian bi~n toc di? cao .
[1 - 3].

4.2. D(>ng Iuc moi tru'ong tr.lm tich WVUTSRQPONMLKJIHGFEDCBA
4 .2 .1 . D (m g

Nhu

lu c

n { J i s in h

da neu,

moi truong

tren ddi nang yeu tan
Nhu

tich bai b6i yen bi~n

kien tao va kien

vay toc di? nang

vao khoang

thuan loi cho qua trinh
day tram tich

tram

tao hien dai voi bien

0,01

mm/nam,

b6i tu Ian tien nhanh

IOn nhu phu ki~u

Nghia

Hung

di? tren duoi 300m.

Day la mot trong
ve phia bi~n

ph at tri~n

nhirng

yeu to

vi khong tao be

thay

moi truong tram tich bai b6i phat tri~n

tren ddi

sut ha.
Trong
gay pha

qua trinh

huy,

Lai Giang,

trong

Day

Richter
d9C theo
nguyen

huang

la dirt

nghien

yeu, ddi nay con chiu anh
cuu narn

tay bac - dong nam,

tay bac - dong nam

- tay nam.

dong bac

dong nang

d6 vung

dinh huang

cua Day, dinh

song

van

Tuong

gay

sinh

duong
nhan

bo Hai Hau

- Nghia

g§'y song

Day c:1t qua cua

dut g§'y song Da truot phai, ciit qua

dut

vdi cac chan

(Hoa Lu) tdi 4,6 - 5,0 di? Richter

dut

cua cac dirt

va dut g§'y cua Day - Van Ly dinh

tv vdi nhieu
chan

giua

huong

(Phat

Hung

gay cua
tam

song

c6 cuong

Diem).

da tung

trung

Hong,

huang
dut

gay

di? M: 3,1 - 3,5 di?

Dirt gay Cua Day -Van Ly

duoc sli dung

trong

viec ly giai

x6i li':lbd bi~n Hai Hau.

4 .2 .2 . D { J n g lu c

n g o o .i s in h

Che di? di?ng luc ngoai

sinh

la t6 hop nhieu

yeu to dong

luc, k~ ca tac dong

cua con nguoi chi phoi qua trinh di chuyen, phan tan b6i tich va l:1ng dong tram
tich .
•

Dong

chay

Son Tay va mang

song.

theo

Ninh
2,577

Co la song nho, chi nhan
x 10

6

tan

phu

8% lucng

sa qua cira Lai Giang.

Iii song Hong tai
Song Day nhan

nude song Hong

tU khu

vue Ha fedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
T a y nhung
thuc te chu y e u tu Nam Dinh

Dao (song

Dinh)

voi khoang

96

Nam

20 - 27% luong

Iii song

Hong

tai

qua song

Son Tay va


Tuyen

mang theo 19,312xl0 G

tij,p T a i n g u y e n . v a M 6 i tr u a n g

tari phu sa [7, 8]. Nhu vay, hang

b iin .

nam c6 khoang

T i j , p fedcbaZYXWVU
X wvutsrqponml

21,889

x l O"tan phu sa qua cua Lai Giang va Cua Day.WVUTSRQPONMLKJIHGFEDCBA
•

Thuy

va m u c n u o c . Nam trong vung anh huang

trte u

chung

cua che' dQ

thuy tri~u ven bo Biic bQ noi chung hay ven bo chau th6 song Hong noi rieng vdi
tinh thuan nha't cua thuy tri~u tcan nhat va dQ IOn giam dan theo vy dQ, thuy
trieu khu v1f.cnghien cuu cling IOn nhat vao cac thang giua mua he (thang 6 va 7)
va cac thang giua mua dong (thang 10 - 12) va cuong suat muc nude cling co th~
dat tdi 0,5

m /h ,

thoi gian trieu

rut dai hen thoi gian tri~u len. Muc nude trung

binh dat 1,85m, nho hon so vdi Hon Dau (1,86m) nhung

IOn hon so vdi Lach

Truong (1,84m). Mac du ap luc trieu IOn nhung v~ mua mua lu, dong song v~n uu
the va khong

dong chay nguoc a vung cua song ca tiing mat va tang

xuat hien

day. Tuy nhien, v~ mua kho, luu luong nude song chi bang 1/3 so vdi mua mua lu,
nhieu

~ila song vung

bd chau

th6 song Hcng xuat hien

khoang each xarn nhap man dai sau vao d6ng bang.
c6 th~ dat toi khoang
khoang each 30 km.

a

dong chay

nguoc va

song Ninh Co, dQ man 1%0

each 32 km tinh tU cua Lai Giang, dQ man 4%0 c6 th~ dat tdi

a

song Day, dQ man 1%0c6 th~ dat khoang

each 20 km tU cua

Day va dQ man 4%0cimg dat tdi khoang each 17 km [7, 8].
Muc nude IOn nhat do thuy tr ieu gay ra ciing chi dat tren 3m, trong khi d6
nude dang trong bao, khong k~ dQ IOn tri~u tuc thi, a cua Day cimg co th~ dat
1,5m (bao Rose, 1968) va tharn chi 1,9m (bao Cecil, 1985). Hien tuong nay khong
nhiing lam thay d6i hinh thai dQng luc cac dang dia hinh trong moi truong tram
tich, ma can anh huang

cue doan den phan bo b6i tich va tharn chi la co che liing

dong tram tich .
•

Dong

chay

ven

bo

va

dong

b e i t ic h

doc bo.

Theo ket qua khao sat cua Phan

vien Hai duong hoc tai Hai Phong trong khuon kh6 cac nhiern vu cap Nha nude
khac nhau trong thoi gian 1999 - 2003 thay rang dong chay uu the huang nam va
tay nam v~ mua dong va nguoc lai, uu the huang dong bac v~ mua he.

v ~ mua dong (mua gio dong bac), dong chay tiing mat huang nam va tay
nam dat toe dQ 19,4 - 39,9
14,1 - 33,3

c m /s

c m /s

vdi tiin suat 44,1 - 78,6%, huang

dong biic dat

vdi tiin suat 8,4 - 23,9%. Dong chay tang- day huang

tay nam dat

toc dQ 37 cm/s,
V~ mua he (mua gi6 tay nam), toc dQ dong chay tiing mat huang
dat tdi 53

c m /s

va toc dQ dong chay mat huang tay nam dat 37

tiing day huang dong bac dat toc dQ 27
Tai Hai Thinh

c m /s .

Dong chay

c m /s .

(phia nam Hai Hau), dong bun cat lo lung ca 2 mua gi6 dong

biic va tay nam
v~ phia tay nam voi t6ng hrong 17 063 692 tan.

Neu tinh chung cho ca doan bo Hai Hau, t6ng luong xuat chuyen
do s6ng ciing dat tdi 1 861 547 m" vdi uu the v~ tay nam 675779

7- TITN

dong bac

b6i tich di day
3

m 1

narn [7, 8].

97


T u y i 'n t g p

•

T iL i n g u y e n . v a M 6 i tr u a n g

Song.

b i i 'n . T g p X WVUTSRQPONMLKJIHGFEDCBA

Song la yeu to di?ng luc ngoai sinh rat quan trong lam bien dang bo

. va suon bo ngarn, pha huy bo fedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
v a tao dong b6i tich doc bo, hoac tao nen cac dang
dia hinh vdi vat lieu hat tho n h u bot ldn, cat. Chinh C6n Xanh, C6n MCiva bCibaa
phia ngoai vung bai b6:i ven bi~n Nghia Hung la ket qua.' heat dorig tich cue cua
song va dong chay doc bo.
Ve mua gio dong bac, song dong bac thinh hanh vdi tuan suat 36,8%, di? cao
khong qua 0,75m, trong do khoang

di? cao dudi 0,25m dat tlin suat 60%, khoang

di? cao 0,25 - 0,75m dat tuan suat 40%. Ve mua gio tay nam, cac song tay nam va
nam thinh hanh voi tan suat llin luot dat 68,5% va 24,7%. Di? cao song trung binh
0,45 - 0,55m va IOn nhat co th~ dat 0,80m.
Do khac nhau

ve hinh

thai bo va suon bCi ngarn

song khong deu theo cac huang.
nang

bo nang Iuong

Khi song dong xuat hien vdi di? cao 1,Om, nang

luong song tai cua Ba Lat dat 1,12 - 1,47 kg/s". Tuong
di? cao 1,0 - 1,5m sinh

ma phan

luong

tu, song dong nam vdi

tai bo Van Ly - Hai Thinh

trong

khoang

1,77 - 2,76 kg/S2 ; song dong - dong nam sinh nang luong tai Van Ly 1',48 kg/s" voi
di? cao 1,65m va 1,4 kg/s" voi di? cao 1,4 kg/s''. Khi song dong bac

xuat

hien d di?

cao 1,Om, dean bCi Ba Lat - Van Ly chiu tac di?ng voi nang luong dat tdi 1,125
kg/s" nhung dean bo Cua Day - Nga Son chiu tac di?ng khong dang k~. Ve mua he
to an bi? khu vue nghien cuu chiu tac dong' manh cua song dong - dong nam, dong
nam va nam - dong nam voi di? cao song cue dai co th~ dat tdi 3,45 - 5,Om, cho
nang luong 5 - 6,49 kg/s" du tlin suat khong dang k~ trong khoang

0,01 - 0,1%

[7, 8].
•

Tee

c J (> n g c u a

con

n q u o i.

Xay dung h6 chua thuong

nguon

la mot trong

nhirng hoat di?ng khai thac hsu vue co anh hudng IOn tdi su phat tri~n bo bi~n do
thay d6i can bang nude va b6i tich d~n den b6i tu hay xoi Id bo.

a

vung dong bac

Vi~t Nam, anh hudng nay khong dang k~. Nhung d vung bo chau th6 song H6ng,
anh hucng

nay rat IOn va dien bien tac dong khong lucng' het duoc. Ca hai phu

luu chinh cua song Hcng deu bi ngan tao h6 chua - h6 chua Hoa Binh tren song
Da va h6 chua Thac Ba tren song Chay. Song Da la phu luu IOn nhat voi dien tieh
luu vue 51 700 km2 tinh tdi Hoa Binh, chiern 50% t6ng thuy luong va 42 - 78%
lucng chay Iii cua h~ thong

song Hong. Dap Hoa Binh co sue chua 9,45

ty m",

chiern 8,29% t6ng thuy lucng narn cua he thong song Hdng va gap 4 llin h6 Thac
Ba. M6i narn, long h6 Hoa Binh nhan 48 trieu tan b6i tich, tucng

duong vdi 83%

luong b6i tich d6 VaG (can 17% qua xa hi) hay chiern 42% t6ng tai lucng phu sa
cua h~ thong song Hcng [7, 8].
Ve mat ly thuyet, su thieu hut b6i tich nhu v~y Ie ra d a gay hieu ung glin
nhu gian dean qua trinh

qua trinh

b6i tu, gay xoi Id manh

me tren

toan

tu y e n

nhung van de phuc tap hen nhieu va d~c bi~t d vung cua Ba Lat va cua Day v~n

98 ZYXWVUTSRQPONMLKJIHGFEDCBA


T u y ln

tijp

'I 'a i n g u y e n . v a M 6 i t r u a n g

tiep tuc b6i tv mo rQng vdi to'c dQ chua tung thay, tren 100m/nam.
"a o "

(Nguyen Hiiu Gli, 2001) do con nguoi tao ra trong qua trinh

dai, chiern cir khong

gian moi truong

tram

tich, phat

tri~n

b iln .

T i i p fedcbaZYXWVUT
X wvutsrqponmlk

Day la to'c dQ WVUTSRQPON
khai kh~n dat

co sd ha tllng thuy

loi.v.v., cudng buc phan bO'cue bQ nguon b6i tich cua h~ thdng song Hong.
Khai hoang Ian bi~n la heat dong khai thac true tiep vung bo bi~n di~n ra
theo vong lich si'1.tao dung van minh song H6ng. Theo tai lieu thong ke (Nguyen
Hoan, 1996 [6]), t6ng dien tich quai de Ian bi~n trong thoi gian 1928 - 1992 tai 17
dia phuong len tdi 14.706 ha, trong d6 c6 1.000 ha d Dong Nam Dien (1978 - 1989)
va 1 100 ha d Tay Nam Dien (1976 - 1984).
4 .3 . T ie n

hoa moi

tr lio n g

tr~m

tic h

D~ danh gia phat trien, tien hoa dia chat moi truong trllm tich, dn

dua

vao

t6 hop cac yeu to'sau:
(1) Dac di~m tudng tram tich thay d6i theo khong gian ph an bO'va theo thoi
gian bi~n hien trong mat cat.
(2) Co che va qua trinh

liing dong tram tich tren

nen ngap chim - t6 hop

cua van dQng kien tao va su dang cao muc nude dai duong the gidi sau
bang ha l11n cuoi va dieu kien dia dong luc hien dai.
(3) Di~n bien b6i tv, x6i Id va tac dQng cua con nguoi trong lich si'1.c6 th~
nhan thay ducc.
Trong lich sir Holoxen, mot trong nhirng thanh tao dia chat dac trung nhat
la cac b6n tich tv hien dai ven bo, trong do vung bai b6i ven bi~n Nghia Hung la
mot bQ phan cau true cua b6:r\ tich tv chau th6 song Hong hien dai vdi nguon nuoi
b6i tich true tiep tir cua Lai Giang va cua Day.
Bang ha l11n cuO'i duoc coi la vao khoang

thoi gian 25.000

narn trudc tdi

20.000 hoac 175.000 narn truce tuy tung tac gia, Thuc chat bien tien sau bang ha
Ian cuO'ibiit dau tU day (bien tien Flandrian)

va bi~n tien Holoxen chi la phan sau

cua bi~n tien nay.
Theo Curray

(1964), bi~n tien sau bang ha Illn cudi biit dllu tu thoi di~m

19.500 - 20.000 narn truce va tien t~inh dang cao muc nude hinh thanh
Pha I tU thdi di~m biit dllu tdi thoi di~m
8 mm/narn.

7.000

narn trudc

ba pha.

vdi to'c dQ dang dat

Vdi to'c dQ dang cao nhu vl%ty,k hong mot yeu to'dia

phuong

nao c6

cuong dQ du IOn (van dQng kien tao hay liing dong tram tic h) ngan can hien tuong
bien tien, cac the h~ duong bd t6n tai khong lau, bi ngap chirn, chon vui va lui

nhanh

ve phia luc dia. Vao khoang thoi gian 8.000 - 6.000 nam trudc.. tien trinh

dang cao muc nude bi~n cham lai va d6i pha l11n thu nhat

va duong nhu c6 su

99 A


T u y ln

tijp T a i n g u y e n

va

M 6 i tr u a n g

b iln .

T i j p fedcbaZYXWVUTSRQPONMLKJIHGFEDC
X

ngung nghi tuong doi d thoi di~m 7.000 narn truoc (Phleger, 1981). Day la dieu
kien thuan

loi lang' dong tram tich thuoc h~ tang Hili Hung (Qr/-2hh). Doi voi

chau th6 song H6ng, Illn:g dong tram tich bllt dau bang viec tao de cat chan ngoai

r6i lap dfty phia trong bang tram tich hat min theo co che' Strickland

(Nguyen

Hiiu Cir, 1999, 2001) r6i ket thuc mot pha md rong' d6ng bang ven bi~n. Trong
mot thoi ky dia chat c6 th~ xuat hien nhieu pha nhu vay va theo d6 h~ thong c6n
cat la dau an mot thoi t6n tai duong bo trong qua khu. Th1,iCchat, cac tram tich
thuoc h~ tftng Hai Hung tu6i Holoxen sdm - gifia d chau th6 song Hong duoc lang'
dong trong thoi gian khoang 8.000 narn trudc.
Pha thu II tu thoi di~m khoang 7.000 narn toi 3.000 narn trtroc ung vdi
Holoxen giira. T6c d9 dang cao muc nude dai duong the gidi d pha nay dat trung
binh 1,3 mrn/nam va muc nude thap hen ngay nay chung 1,5m d cuci pha. Vao
pha thu III, tu 3.000 nam truce tdi ngay nay (ung voi Holoxen muon), toc d9 dang
cao muc nude chi vao khoang 0,5mm/nam. Cac tram tich tre hon chong goi tram
tich cua h~ tftng Hai Hung da duoc Hoang Ngoc

Ky

(1976) xep vao h~ tftng Thai

Binh, tu6i Holoxen muon (Qrv3tb).Th1,iCra, tram tich cua h~ tftng Thai Binh dU<;JC
tich tu tU thoi di~m truce 3.000 narn, c6 tu6i Holoxen gifia - muon (Q ry 2-3).
Qua trinh ph at tri~n d6ng bang song H6ng trong Holoxen muon, d~c biet la
cuoi Holoxen muon, bi tac d{mg manh cua con nguoi d~n den pha vd can bang t1,i
nhien cua chau th6 giua ph at tri~n n6i cao va Ian tien vdi uu the Ian tien ra bi~n.
Day la ket qua tr'uc tiep cua h~ thong de ngan Hi, ngan man lam thu hE?Pmoi
truong tram tich' va cudng buc phan bo cue b9 nguon b6i tich tu song, H~ thong
c6n cat Holoxen sdrn - giua keo dai khong lien tuc tu Yen Mo (Ninh Binh) , C6 L~
(Nam Dinh) tdi Vu Thu (Thai Binh) cung voi cac cong trinh nhan tao sau nay dii'
chan nguon nuoi b6i tich trong qua trinh phat tri~n n6i cao cua chau th6, tao nen

vung trfing thap rong IOn phia tay nam chau th6 song Hong. Neu vung triing Ha
Nam (phia tay thanh pho Nam Dinh) duoc nuoi b6i tich tu nhien, thi doan bo tir
Diem Dien tdi LachTr-ucng

h~n khong c6 hinh thai nhu hien nay 16i cue b9 trong

cung b6i tu, Cac h~ thong c6n cat tiep theo ve phia bi~n Ia nhung dau an r6 net
ghi lai duong bo d cac thoi di~m 2 300 - 2 000 narn va 700 - 500 nam truce. Phat
tri~n theo co che' lap dfty tiep theo vdi su can thiep marih me cua con nguoi (dap
de ngan Iii, de ngan man, chan dllp luong lach va phan hru) dii lam xuat hien hai
cung 16i cue b9 - cua Day va cua Ba Lat, vdi toc d9 Ian bi~n qua nhanh (100 - 120
m/nam) trong khi be mat dong bang phfa trong khong con nguon nuoi b6i tfch,
M9t Ian nfia c6 th~ n6i rllng day la toc d9 "ao" do chinh con nguci tao ra va viec
danh gia tiern nang bai b6i, mat nude can than trong hon.
Vung bai b6i ven bi~n Nghia Hung ciing phat trien theo co che lap dfty trong
pha b6i tu muon nhat · cua su phat tri~n ddi be chau th6 song H6ng hien dai.
Thanh tao cat keo dai tU de Nghia Phuc tdi C6n Xanh, C6n Mo va tdi cira Day, la
100 ZYXWVUTSRQPONMLKJIHGFEDCBA


T uye"n

tifp

Tai

va M 6i

nguyen

tr u o n g

su«

T ifp

X

ke't qua true tiep cua dong chay va s6ng, dong vai tro bo chan ngoai mot vung
r9ng IOn tdi tan bo de Nam Dien, ma trong do tram tich hat min dang dan duoc
tich tu. C6 th~ mo phong qua trinh phat tri~n vung bai b6i ven bi~n Nghia Hung
theo co che' lap d~y (hinh 3). Theo do, mot pha b6i tu g6m ba giai doan:
1 tich tu tao nen day, tuong ling voi bai trieu thap cau tao chu

, G ia i d o a n .

yeu tir bot IOn l§.n cat nho, manh vun va sinh vat.
, G ia i d o a ti

2 tich tu tao de cat ngarn hoac c6n nho s6ng va dong chay doc bo

voi nguon b6i tich true tiep tu bai trieu thap va suon be ngarn nho tac d9ng cua
s6ng va b6i tich di chuyen doc bd nho dong chay, thuong lien quan de'n dean be ke'
can bi pha huy. Doi vdi vung bai b6i yen bi~n Nghia Hung, qua trinh thanh tao
C6n Xanh, C6n Mo c6 lien quan tdi su pha huy bd bi~n Hai Hau, tao dong b6i tich
di chuyen ve phia tay nam.
, G ia i d o a n .

3 tich tu lap d~y bang tram tich hat min nho dong trreu.

- 3--- - . ..2 fedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
. -_-_-_-_-.3.-_-_-_-_-. A
0

---

•

- -:- 1...:. -:- ....:.. -:- ...:.. -:-

0

~~~~-=~~~--------~
• -:- ' -:- ' -:-.:. 1 -;- .; -:- .;WVUTSRQPONMLKJIHGFEDCBA
ZYXWVUTSRQPONML
r : ...:- ..
: -.: - : - .; - : - .; - : - '

• -:-

= :

.;

-:-

.;

-:-

.;

cua p h a b e i tu tao n e n d a y V d j tra m tic h b 9 t
lcn, tl.td n g · bai trie u th a p , 2· G ia i dean g iiia cua p h a b e i tu tao
d e chan v d i tra m tich c a t, tl1 0 n g bai, 3 - G ia i dean cuo] cua
1 - G ia i d o a n d a u

p h a b e i tu

la p d a y v o j tra m tich

bun b9t nho, bun

s e t bot,

tirdriq b a i trie u c a o

H in h

3. Mo hinh mc)t pha b6i tv theo

cd

che' Hip d~y

Qua 9 mat ciit 16 khoan th~ hien tren hinh 2 thay dng

tram tich hat min

tich tu theo co che' lap day c6 be day thay d6i tuy noi tu 40 ern, 80 em tdi

it

nhat

125 ern. 81;£ thay d6i be day nay la do tich tu lap d~y nen dia hinh phan di d9 cao,
phan cllt bdi h~ thong lach trieu, Be day IOn tram tich hat min lap d~y lach trieu
khong dai dien cho toan vung bai b6i ma kha di hen la lay trung binh 80 ern. D~
tinh toc d9 tich tu lap d~y, c6 th~ xem xet tien trinh b6i tu md r9ng va chon moc
101


T u y ln

tij,p T a i n g u y e n . v a M 6 i tr u o n g

b iln .

T i j , p fedcbaZYXWVUTSRQPONMLKJIHGFEDC
X

thoi gian tuong doi xac thuc. Vung bai b6i yen bi~n Nghia Hung hien nay la mot
b9 phan keo dai lien tiep cua vung bai b6i Rang Dong truce day ma trong tu lieu
lich slt. con ghi nhan duoc tu narn 1930. Theo danh gia b6i tu bang phuong phap
xlt. ly anh v~ tinh ket hop vdi ban d6 cac the h~ va khao sat mat dat (Tr~n Van
Dien [8]) thay rang:
- Trong giai dean 1930 - 1965, b6i tu di~n ra tren chieu dai 13.750 m, md
r9ng duoc 3 459,618 ha, dat toc d9 trung binh 71,89 m/narn.
-' Trong khoang thoi gian 1965 - 1991, b6i tu dien ra tren chieu dai 9.200m,
md rong' duoc 1.532,205 ha, dat toc d9 trung binh 64,06 m/narn.

- Trong khoang thoi gian 1991 - 1995, b6i tu tren chieu dai 15.200m md rong
duoc 917,5735 ha, dat toc d9 trung binh 120,7 m/narn va cao nhat trong thoi gian
1930 - 1995.
Theo co che' tich tu lap day, toe d9 md rong cao nhu v~y khong co nghia la
nhin thay m6i nam tien ra bi~n 120,7m ma la khoang each duoc md rong' se 6n
dinh tuong doi cho toi khi xuat hien de cat moi phia ngoai d~ t9-0 mot pha maio
Theo quy luat ph at tri~n tv nhien (Strickland,

1926 [6,9]), khi bon tich tu dUQC

lap d~y thanh t9-0 d6ng bang thap voi cac lach trieu tan (kieu polder) thi co co h9i
xuat hien mot pha mdi voi cac thanh t9-0 nen day (1) va b2.Jchan (2) nhu mo phong
tren hinh 3. Nhung trong thuc te lich su, con nguoi dil can thiep sau siic VaGqua
trinh nay lam cho cac vung trimg khong dat duoc d9 cao tv nhien va rut ngan
thoi gian t9-0 nen mot pha tich tu mdi.
Nhu vay, cac tu lieu phan tich tren cung vdi su xuat hien h~ thong de cuoi
cung cho phep xac dinh t~ng tram tich hat rnin phan

anh qua cac mat ciit 16

khoan duoc tich tu trong khoang thoi gian tir nam 1990 tdi nay va toc d9 tich tu
lap d~y trung binh dat 6,6 cm/narn (C\lCb9 co th~ tren 10 cm/narn d lach trudc
day), cao hen toc d9 tich tu n6i cao trong dai rung ngap man Bang La (6 cm/narn)
trong thoi gian 1992 - 2002. Hen nira can cu VaGd9 cao dia hinh vung bai b6i yen
bi~n Nghia Hung co th~ nhan dinh dng

toc d9 6,6 cm/narn la d khoang giiia pha

tich tu lap day, cham hen so vdi pha dau va nhanh

hon so vdi cufii pha va tram

tich hat min hon (bun set bot) se uu the so vdi bun b9t nho hien nay.

•

Vung bai b6i yen bi~n Nghia Hung duoc tich tu theo co che' lap d~y vdi toc
d9 trung binh dat tdi 6,6 cm/narn, C\lCb9 co th~ dat tren 10 cm/narn d noi co

102 ZYXWVUTSRQPONMLKJIHGFEDCBA


Q

T u y ln

cac lach

trieu

trudc

tifP

'I 'a i n g u y e n .

va

M 6 i tr u o n g

day bi lEip d~y, g6m chu y e u la bun

b i e " n . T t i p fedcbaZYXWVUTS
X wvutsrqponmlk

bot nho mau

nau

duoc bao b9C boi dai cat nho, bot IOn keo dai lien tuc tir cua L0i Giang

tdi

cua Day.
•

Tram

tich

Holocene

bai

b6i ven

muon

thuoc

bi~n

Nghia

h~ tang

Thai

Hung

la phan

tren

cung

cua

(Qry tb) g6m ba ki~u tudng

goc ling vdi ba giai dean cua pha tich tv theo co che' lap day: tudng
thap

(k~ ca suon bd ngam)

bot ldn, tuong

thanh

phan

Qua trinh

2 t00 bo chan

bai trieu cao ling voi giai dean

binh cua hai loai tram

nguon

bib trieu

day voi thanh
ngoai

dt

c6 thanh

phan
phan

3 lap d~y bon tich tv vdi
kinh

tich nay tuong

bun

set b<)t nhung

doi g~n nhau.

tram tich t00 bai b6i ven bi~n Nghia Hung c6 ngucn nuoi b6i tich

tU cua Day chu yeu cho thanh
giai doan

1 t00 nen

chu yeu Ia bun bot nho, cue b<) c6 thau

duong kinh trung
•

ling vdi giai doan

bai bi~n ling vdi giai dean

cat nho va tudng

mat

3

Binh

t00 lEip d~y nho dong trieu,

b6i tv, tu siren bo ngam,

3 cua pha

Hau do x6i 10 t00 dong b6i tich di chuyen
t00 nen day trong

dong song trong
va tu bo Hai

cua L0i Giang

ve phia tay nam chu y e u cho thanh

giai doan 1 va bd bao trong

giai doan 2 cua pha b6i tv nho

s6ng va dong chay d9C bo.

'"

?

TAl LI~U THAM KHAO
1. Nguyen Hfru Cli, Nguy~n Vii 'I'uan, 2001.
Tac dong cua con nguoi

toi moi truong

dia chat

vung bd chau

th6 song H6ng.

Tai nguyen va Moi truong bi~n, T?p VIII, NXB Khoa hoc va Ky thuat, Ha N<)i,
tr. 43-53.

2. Nguyen

Hiru Cli, Tnln

Due 'I'ha nh, INguy~n Vii Tuanl, Nguyen

Quang

'I'uan, D:Img Hoai Nhon, Nguyen 'I'h] Kini Anh, Bui Van Vuong, 2003.
Cau true va tie'n h6a dia chat vung bai b6i ven bi~n Nghia
. Khoa h9C quy hoach
Dinh). Luu trir 0 Phan

stt dung

Hung.

hop ly vung bai b6i ven bi~n Nghia

De tai Co SO
Hung

(Nam

vien Hai duong h9C tai Hai Phong.

3. Dinh Van Huy, Nguy~n Hiru Cli va nnk, 2000.
Dac di~m dia dong luc bd chau
1999-2000.

Luu trfi 0 Phan

th6 song H6ng.

Z

Bao cao de tai cap co SO narn

vien Hai duong h9C tai Hai Phong.

103


T u y in

tlj,p T a i n g u y e n

va

M 6 i tr u a n g

b iin .

T t i p fedcbaZYXWVUTSRQPONMLKJIHGFEDC
X

4. Hoang Ngoc Ky va nnk., 1978.
Ban d6 dia chat va khoang san ty l~ 1: 200

ooo,

td Hai Phong - Nam Dinh.

Luu tru 0 C\lC Dia chat va Khoang san Vi~t Nam.
5. Trlln Dinh Lfm, Trlln Due Thljlnh, 1991.
Hinh thai, phan b6 tram tich va dac di~m b6i tu bai b6i ven bi~n huyen Kim
Son. 'I'ai nguyen va Mci truong bien, 'I'ap I (T6m d.t cac cong trinh nghien cuu
1986 - 1990). NXB Khoa h9C va ~ Y thuat, Ha NQi, tr. 33 - 39.
6. Nguyen Ngoc, Nguyen Hiru WVUTSRQPONMLKJIHGFEDCBA
C d va Trlln Due T'hanh, 2000.
D~c di~m dia chat D~ tU va tien hoa ..ce>dia ly ddi be chau the> song Hong trong
Holocene. Bao cao chuyen de thuoc De tai KHCN - 5A (1999 - 2000). Luu tru 0
Phan vien Hai duong h9C tai Hai Phong.

7. Tr~n Due 'I'hanh,

Nguyen

Due Cu, Nguy~n

Huu

Cli, DB Dinh

Chien va nnk, 2000.
Nghien cuu du bao phong
Thanh

chong sat 10 b o bi~n bac

BQ

tU Quang

Ninh tdi

Hoa. Bao cao te>ng hop De tai cap nha nude KHCN - 5A (1999 - 2000).

Luu trfi 0 Phan vien Hai duong h9C tai Hai Phong.
8. Trlln Dire 'I'ha nh, Ngu yen Hiru C d , D6 Dinh Chien va nnk, 2000.
Du bao hien tuqr;tg x6i 10, b6i tu bd bien cua song mien Bac va giai phap phong
chong. Ket qua thuc hien 2001 - 2002 thuoc De tai cap Nha nude KC - 09 - 05
(2001 - 2004). Luu trfi 0 Ph an vien Hai duong h9C tai Hili Phong.
9. Xamoilov, LV., 1952.
Cac vung cua song. Nha xuat ban Qu6c gia "Van lieu dia ly ", Moskva (tieng'
Nga).ZYXWVUTSRQPONMLKJIHGFEDCBA
10. Zencovitch, V.P., 1962.
Luan di~m co ban ve ly thuyet thanh

tao cac dang tich tu ddi be bi~n. Dia chat

bien v~ dong luc be, T~p X, Quy~n 3. NXB Vien han lam khoa h9C Lien XO, tr.
88 - 101 (tieng Nga).

104


t ~ p WVUTSRQPONMLKJIHGFEDCBA
T a i n g u y e n v a M o i t r u i m g b i l n . T ~ p fedcbaZYXWVUT
X wvutsrqponmlk

T u y ln

SUMMARY
GEOLOGICAL

STRUCTURE

AND EVOLUTION

OF THE NGHIA HUNG TIDAL FLAT AREA
N guyen

I N guyen

H uu

Vu Tuan

C u, T ran
~ N guyen

D ang H oai N hon,

N guyen

D ue Thanh,
Q uang
T h i K im

Bui

A s a p a rt o f th e
(N a m d in h

p ro v in c e )

com posed

o f fin e

m u d . T h e fin e
(s o rtin g )

sand,

sand

w ith

o f 1 .2 5 0 -1 .5 9 2

o f 1 .2 6 2

-

1 .9 3 0

riv e r d e lta ,

s o u th w e s t

a re a fro m th e N in h c o

a le u ritic

Red

and

th e tid a l fla t a re a

o f th e N in h c o

c o a rs e

a le u rite ,

M d (m e d ia n

s e d im e n ts

a le u ritic

S k o f 0 .2 1 2

-

o f 0 .7 9 1 -

1 .0 9 6

in n e r

lo w

Van Vuong

N g h ia h u n g

d is tric t

o f th e D a y riv e r is

and

a le u ritic

o f 0 .1 0 2

1 .0 0 0 fo rm s

-

th e fin e

sand

p e litic

So

- 0 .1 3 1 m m ,

a b e lt fro n tin g

w ith M d o f 0 .0 5 8 - 0 .0 9 5

b o rd e rs

Anh,

b e lt. T h e

mm

th e

So

,

fin e -

S o o f 1 .1 5 1 - 3 .1 5 9 a n d S k o f 0 .0 6 4 - 1 .5 2 8

o f th e a re a . T h e a le u rltic

c o n s titu te

m ud

in a ra n g e

riv e r m o u th . T h e c o a rs e a le u rite

S o o f 2 .4 3 4 - 3 .3 1 5 a n d S k o f 0 .7 2 8 -1 .6 4 5
These

-

d ia m e te r)

m u d w ith M d o f 0 .0 1 5 - 0 .0 4 7 m m ,

fills u p th e c e n tre

riv e r a n d n o rth e a s t

fin e

a n d S k (d e v ia tio n )

o f th e

Tuan,

- p e litic m u d w ith M d o f 0 .0 0 9 - 0 .0 1 O m m ,
a p p e a rs

and

h ig h

re s tric tiv e ly
tid a l

fla ts

in th e D a y riv e r b e d .
and

o u te r

beach

and

b a rrie rs .
T h e c o n s id e ra tio n
s e d im e n ts

o f s u rfa c ia l

a n d s tra tig ra p h ia c a l

in th e a re a s h o w s th a t th e y w e re a c c u m u la te d

d is trib u tio n

c h a ra c te ris tic s

d u rin g th e y e a rs

of

1 9 9 0 -2 0 0 2

w ith 3 s ta g e s o f:
(1 ) - fo rm in g

th e b e d w ith c o a rs e a le u rite ,

(2 ) - b u ild in g

u p th e fro n ta l

(3 ) - in fillin g

th e c e n tre

b o d y o f fin e s a n d , a n d

o f th e a re a w ith fin e - a le u ritic

m u d a t a ra te o f 6 .6 c m

a

y e a r.

105ZYXWVUTSRQPON