Đặc điểm phát triển của khu vực ven bờ đồ sơn – hạ long trong holocen (geological development of coastal do son – ha long area during holocene) địa chất và địa vật lí biển

lRUNG

TAM KHOA Hoe

TV NHIEN

V xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
A eONG NGHe Quae GIA

VI~N MLKJIHGFEDCBA
H A l D l1 0 N G

cAc

CONG
"',

HOC

T R IN H N G H IE N C tJ U
"",..?

D I• A C H A T V A D I••A V A T L V B I E N
"
T~P

III

NHA XUAT BAN KHOA HOC vA KY THU~T
HA N()f - 1997

,


13. N guyin D tic Vinh, N guyin van Luong. xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFE

m ii
Nghien cuu dl:lc diem song dia chan phan xa tiJ dut gay truoc gU
hinh toan.

136

14. N guyin N goc, Trim van H oang, D olin L¢ Thanh.
Mi)t s6 net ve m6i truong dia chat diJi ven bien Nam Trung Bi) (phan dilt lien).

144

15. Triin Van H oang.
Buoc dau tim hieu m6i quan h~ gifla cac thanh tao chua c6 ket v(}ibieu hien cua
hien tuong bien dang hin be mat dat do bom hut nuiJc duiJi dilt iJ Ha NQi.

162

16. N guyin N goc, N guyJn H iiu C it, N guyin H oiin, D ao Thi M ien.

dl dja Iy khu vue gieng khoan BH2 (bOn
Sinh dia tang va dl:lc diem hoan canh ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
trung CiJu Long them luc dia Nam Vi~t Nam).

169

17. Triin Van H oang, D olin Lf Thanh.
Phan vung dieu kien dia chat cling trinh vung ven bien Nam Trung Bi).

18. N guyin The
<"

186

tu».

Lien h~ cac bac dia hinh v(}icac thdi ky bien diJng tren them luc d!a Vi~t Nam.

192

19. Triin D tic Thanh, N guyJn C tln, D iing D tic N ga.
Dl:lcdiem phat trien cua khu vue ven bo DO S
20. N guyin tu «

tuu, N guyin

Holoxen.

199

van Bach, N guyin H uy PhU c, N guyin van N hiin.

Vai net ve van de phan loai cac thanh tao cat dai ven bien mien Trung.

213

21. N guyin T ien H tii, N guyin van Bach
Dl:lc tinh bien d(jng cua cac dai cat ven bien mien Trung (Quang
Thuan)

Binh - Binh

va hau qua cua cluing.

222

22. N guyin Van N hiin, N guyin van Bach, N guyin Tien H ili, N guyin H uy P huc.
Dl:lcdiem phan b6 cac tram tich tang mat bien mien Trung.

23. U X utin H O ng, P ham Van N inh,

ts van Thanh, N guyJn The tu», N guyin

234
H oan.

Hien trang xoi liJ biJ bien Vi~t Nam va xu the phat trien cua no.

243

24. D oan Van H ung.
Tiem nang khoang

san tinh Phu Yen.

251

25. Bui H O ng Long.
/'

MQt so ket qua khao sat dl:lc diem dQng luc tren bai trieu vung Phan Ri ciJa
(Binh Thuan)

va moi lien quan cua chung tili su bien diJi dia hinh biJ va day.

258

THONG BAa KHOA HOC
26. N guyin N goc, N guyin H isu C it, H a Van C hien.
Cac di tich Foraminifera

trong tram tich bai bien dao Nam Yet quan dao

Truong Sa (Vi~t Nam) va

y

nghia cua chung.

271

27. N guyin N g(Jc Thach.
Ap dung vien tham va h ~ thong thong tin dia Iy nghien cuu bien d(ing liJp phil

m~t dilt lay vi du iJ vung Sterting

6

va Kuala Pilah, Malaysia.

278


cuu xwvutsrqponmlkjihgfedcbaZYXWVUTS

CAC CONG TRINH NGHIEN

DJA CHAT VA DJA V~T LY BIEI

NHA

vA

XUAT BAN KHOA HOC

v

,,"

D~C

,

D IE M

,,"

KY THUAT,

HA NOI,

1997

.,

,

P H A T T R IE N C U A

00 S O N

- T~P MLKJIHGFEDCBA
III

K H U V t)C

- H J :\L O N G T R a N G

VEN BO

HOLOXEN

~

T rail jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
D u:c Thanh, N K uyhl C all , D {iIlK D ire N K a
G E O L O G IC A L
COSON

D E V E L O P M E !N T

- HALONG

AREA

OF

D U R IN G

*edcbaZYXWVUTSRQPON

COASTAL
HOLOCENE

ABSTRACT
As

a result

"m ovem ent
studied

of co m b in at io n of e ust a tic sea

and sedim entary

area is divided

or all ingression

process,

the H olocene

i!110 three periods.

w ith

the shoreline

regression w ith the shoreline m oving
tile stages w ith the characteristic
- The first period

-+- Early H olocene
and restricted

+

M iddle

m oving

sedim entary

- beginning

change,

geological

t ect onic

developm ent

o]

They ure begun by a transgression

seaw ard.

(early - m iddle

level

landw ard

and

ended

The period can he divided

hy

1I

into

environm ents.

H oloccn ) consists o] three stages.
o] m iddle

H olocene:

C oastal plain,

lakes

hays.
M iddle

H olocene:

Lagoons

and hays w ith m ost expansive

sea

area.

+

Late m iddle

H olocene:

- 'The second period

+
+
+

(late H olocene)

Early late H olocene:
M iddle

expanded

late H olocene:

Late late H olocene:

- The third period

C oastal sw am ps,

hays and lagoons

expanded

lagoons and hays.

delta, estuaries and bays.

(latest H olocene,

of estuaries

hays

consist o] three stages.

been begun and consists o] one stageonly
environm ents

lakes and restricted

about

50{)-700 past years)

w .ilh the characteristic

has just

sedim entary

and bays.

* Tnf()ng Dai hoc Khoa hoc Tu nhicn - Ha Noi.

199


From the obtained

or coastal

data, a few predictions

developm ent

o]' this

area edcbaZYXWVUTSRQPONMLKJIHGFEDCBA
ill the [uture
w as given. ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

*
*
I.

MO

*MLKJIHGFEDCBA

xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

DAU

Khu vue ven hi) D() Son - Ha Lonu
•

•

Iy co ban

I~Ivung

H<;I Long,

vinh

phat

Holmen

trong

the

sinh dia tang,
Sll dung

KHAI

TRUDC

Bach

Cua

d ua

Luc.

V~IO

Day la mot

Yen Lap),

tich

V~I

D~C

trt.~ng can duoc
sat nhie u

ve

t{)ng hop cac tu lieu

tich. dja rnao. tfln k ien t~1O va kien tao hien

nunc

IlWC

D IE M

chan

t inh

[7) del Cc1 dip duoc

c()
dai

chung

PHAT

T R IE N

D IA

CHAT

KHU

V l) 'C

HOLOXEN

khu

V~IC

nghie n CCIU

Trorig

Bang.

Oligoxen

true ne n e p cue da i phuorig
hoar dOng truot

hao Nengen

huck

cJ vi tuyen

muon.

trunng

va h~ thling

btlllg trai. Chuye n dong

da h inh tha nh

-:{IC

tao tich

de)i nung

ung suat

TienYen

kien

{I

o ven

VI tuyen.

tuy nam

hac,

va dong

pharn vi sut ha tuong

Chuyen

dOng

Plioxen

sorn - Plioxen

gilla.

bi nang

cao,

thanh

Plioxen

muon

true ep nen

chia

cat

k ien tao yeu dan,

Mot

be

C~IC

dai phuong

cJ kinh tuyen

0 phun

dong bac khu vue. C~IC dut gH~ dut gay Nui Deo

- Do Son

ClJ

vai tro quan

moi hinh

cao

- D~ Tu, hoar de)ng k ien tao manh

diu
YCS
nam

huong

tay

tro le n yen tl~h vao cuui

Ill~lt san hang

cac d()i nui thap

co

deli, phat

trie n m(11 v(mg dia hao doc true dut gay Kinh M C )n - Hai Phong
hac dC)ng narn.

tao

kh{)i tang d,I hinh thanh trung
phia

cue

dut gciy chu dao TB-DN

L~lC oi khCing che boi cac dut gay

Cua

Dtlng,

- Mioxen

hout dong kien

V~I()

dut g,ly sflu Song Hong,

ba o qua nh vung sur ha tuo ng drii. Trong

200

diem

trien dia chat

phelt

ngh ie n cuu khao

U~I

vinh

khu vue trong

het sue quan

IH)C

ket q

•

(ke' dl vung

ma d~IC diem

cung vo i hout u(1ng trt) la i cua he th()ng

Bach

<'

i k h u v u C [I I).

VE

Tu Oligoxen,

- Cao

•

Dang

co Sl) khou

tu lie u dew dOng

QUAT

•••..•

tre n Cl1 Sl~ phan

k hao cll, tram

V l)

bao uom mot s6 don vi diu true dia

ve moi trunng

nhung

t{IC gi~1

in h I ~I ph II h l) P

II.

H~I va vjnh

Ba i vie: nay duoc

narn cua t0p

III

(VCS)

te va bao

la mot

qua n tarn.

V~I

Lan

kinh

trien

cua song

••••.

Jon -

thanh,

250m

len voi truong
ray narn va

TB-DN
trong

a

[J,ll].

Vao

ung slJat_ co
VI tuyen

deu truot
trong

sau nay

binh

bang

phan
phai.

do chuyen


Oai kiEin true nang trong
va kiEin tao hien dai

tan kiEin tao
.A-"

..- -* Out gay heat dong trong giai dean tan
kiEin tao va kiEin tao hien dai co billu

hien dOng d§t trung binh cao

kiEin xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
Out gay heat dong trong giai doan tan
~
kiEin tao va kiEin tao hien d~i co billu
OC)i billu hi~n 'n-arig ha kiEin tao tudng
hien dong d§t trung binh th§p
doi trong giai doan hien dai
.....- Out gay tan kiEin tao va kiEin tao hien
Ranh giai dai nang ha tudng deli mann
...........d1;l.ic6 bi@u hi en dong d§t yEiu
trong Holoxen
Oai billu hien nang di'eu hoa trong
tao hi en dai
~.

OuClng dAng tr] bien do nang ha kiEin tao

O~lt gay thuan
earn cua mM

vach

ngi\.n chi' huang

truot

out g~y sau, heat dong trong giai doan
tar) kien tao va kiEin tao hien dal c6

bieu hien dong dift rnanh

" trong

Phudng truot cua dUt gay
Oligoxen-Mioxen
(P 3-Nl)
Phudng truct cua dUt gay
Oliqo xen-De tu (N2-Q)

Hinh 1. So

do

trong

pha
pha

o
o

o
o

kien true tan kien

Chan tam

dong

d§t

dat 2,5-3 dO Richter

Ch§n tam
Richter

dong

d§t

dat 4,1-4,5 dO

Ch§n tam dong edcbaZYXWVUTSRQPONMLKJIHGF
d§t dat 4,6-5,0 dO
Richter

Ch§n tam dong
Richter

1(;10.

d§t

kien tao hien

dat 5,1-5,0 dO
.

lli;li

va bieu hien dia chan vung dCa song Bach Dang,

Sl-Ccr.T3

201


0

dong khoi tang hien dai.

phan tay nam dut gay thuan

truot hudng nam lien ket voi cac dirt gay phuong

DB-TN chuyen

nguoc chieu cua he dut gay cung phuong

Su dich chuyen

. true dut g~y Nui Deo

ne n dia hao hien
Pleixtoxen,

a vi tuyen c6 mat
dich phai.

DB-TN

hai ben

- Do Son da t<;10ra co che tach gian va hinh thanh

dai 6 trung

tam

yes

Bach

Dang

(h inh 1)[1]: Trong

tai cac bon trung ton tai moi truong luc dia, lang dong cac tram

tich cuoi, cat aluvi day den 30m. Vao cudi Pleixtoxen
bien tien t<;10nen phuc he tram

c6 mot dot

muon

tich chau tho day den 27m 6

yes

Bach

Dang. Van dong kien tao nang ket hQP voi ha chan tinh da triet thoai che
dO ven bien va day lui duong bo den do sau IOO-120m ngoai Vinh Bac Bo.
.11I. D~C MLKJIHGFEDCBA
D IE M
P H A T T R IE N
TRONG

HOLOXEN

VUNG

BO, D O

VEN

SON

- HA

LONG

edcbaZYXWVUTSRQPONMLKJIHGFEDCBA

B anI: jihgfedcbaZYXW
J
C dc giai doan phdt trien cua khu

V lfC

yen bir

Do

Sun - H a Long trong H oloxen ,"
I

Thbi

ky

B<;tch

VCS

Giai

dO<:ln

Vinh

Dang

L\IC

Luc dia, phan

Holoxcn

I

Cua xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPO
Vinh H<:I
DN Oit B1I

I Ho

luc dia

I'
I

ngoai

thanh

I
I

I (Lan H<;t)
luc I Vinh bien van

Long

I

Dong hang

dia

cuoi giai doan

!

vinh hep van
cuoi giai doan

i
I

som

2

Vjnh

Vinh hien

bien-

(Tong nhat)

v\lng bien
gilla

I
!
I

Vinh

bidn-

i Vinh bien (thul

Holoxen
muon

202

Cua

song

chau

Vinh

kieu

estuary

Cua song hinh

Vinh kieu

Tong)

hien

hep)

est

uaTY
Jong)

(mo

I

Vinh

Vinh

hicn

hicn

Tong)

I
:

-----I-----

tho

pheu (mo

Vinh

I

hep)

I

-----7"----:f-----------J.. ,

Cu6i

(TOng nhat)

V\lng bidn

2

3

(Tong nhat)

bien

dia ven bien

,
muon

Vinh

hi en

Dam lay 1\1<.:

3

Holoxen

Vinh

(mo

:

Vinh

bien

Vinh

hien


Qua

tr inh phat

Holoxen

tr ien dia chat vung yen bo D'O Son - Ha Long trong

ehia lam 3 tho: ky.ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
Moi thoi ky thu nhat va thu hai duoc

duoc

ky

ph an lam 3 giai doan. Thoi

thu 3 moi bat dau va dang tiep tuc.

1. Thili ky thd' nh~t
Thoi ky nay van Holoxen

sorn - giua, khoang

11-3 nghin

Bien tien chan tinh c6 vai tro chu dao doi voi qua trinh
yen bo, lam bien doi nhanh chong tu moi truong

narn truce.

ngapchim vung

luc dia sang yen bien, day

lui duong bo xa nhat ve phia luc dia. Vao cudi thoi ky muc nude chan tinh
tao va tich tu tram tich duoc tang

dang cham h~n, vai tro chuyen dongkien

cuong, duong bo dich chuyen ve phia bien, bien lui va vung trieu mo rong.jihgfedcbaZYXWV
1. G iai edcbaZYXWVUTSRQPONMLKJIHGFEDCBA
40f!.R I

M6i truong luc dia chuyen tiep thanh yen bien, khoang
truoc

(Holoxen

sorn - dau HoJoxen

tren

l Gmrn/n am va ha xudng

nhanh,

] 1-7 nghin narn

giua ). Muc bien cha n tinh dang rat
9mm/n[uTI

van ranh

g io i Pleix -

[7] ling voi duong bo c6 d¢ sau 60111duoi day vinh Bac B¢ van 11 -

Holoxen

nghin narn truce. Den 8 nghin narn truce duong bo tien den sat ria ngoai

vinh Lan Ha va phan ngoai VCS Bach Dang. Khoang
bien tran

vao vinh

Long. Phan
phat trien

8-7 nghin narn truce

Lan H~ va vung

nude giua D() Son - Cat Ba - vinh H~

tich VCS Bach

Dang van 18. d(1I1gbang luc dia yen bo,

Ion dien

cac bai boi song, hc} dam. Vinh Cua Luc co ban van la mot ho

.

nuoc nhat, bi anh huong Jon

V~lO

mua kho do truyen

man thee trieu nguoc

song ..
G iai doan 2

Mo i tr uong
(Holoxen

nhat

tr onzI:> pham
•
cac

- vurig

giua). Day la giai dean

7000-5600
vao

v i n h bien

nam

chan

vi vung

truoc,
nui.

kh o a ng 7-4 ngh in narn truce

bien tien Holoxen

tran ng?p va mo rong

nghie n cuu. Vao nua da u I:>uia i doan.,

duong

Vinh

bien,

bo lien tuc di chuyen

bien dune

ve phia luc dia va ap sat

mo rorig nhung

nong. Tram

trieu phan bo 0 cac bon sut ha tuong doi manh trong Holoxen.
con lai, chu yeu

la tram tich vung trieu,

vet. Bai Jay su vet thuong
Thuy Nguyen,
vinh

vung

bien thong

dong Karsto

tao thanh

g()m bai trieu thap,

tich

6

duoi

cac doi

bai trieu Jay su

dai rong phia lay, lay bac Cat Ba, bac

Yen Lap va quanh

voi vinh

khoang

ria Cua Luc. Cua Luc da rro thanh

Ht;t Long. Vinh

H~ Long

ban chat la mot canh

co, narn tren vung nang yeu kien tao, bi ngap chim vi toe d¢

203


nang chan tinh VUQt qua nang kien tao va toe dO tram tich rat nho.
Do quan h~ toc do giua nang chan tinh va nang kien tao, VaG khoang
5600 narn truce,

duong

bo bien tuong doi tinh tai, mot he thong them tich

tu bien va ngan bien tren bo vach da voi cao 5-6m duoc hinh thanh.
them cung dO cao kha pho bien 0 ven ria Quang

Cac

Yen, Yen Lap, ven vinh

Ha Long va vinh Cua Luc, Cac ran san ho rat phat trien 0 dong nam Cat
Ba, tharn chi 0 ven ria dao Hon Dau, Do Son. Tac dong cua s6ng eOng tao
ne n cac cung
Hoang

bo boi tu va cac doi cat ndi dao 0 Do Son, Quang

Yen,

Tan,ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
Tuan Chau.

Vao nua sau giai doan,

khoang

tuong doi cua muc bien va boi

t1..1

5600-4000

narn truoc,

e6 su ha thjip

noi cao, rno rong. Che dO vinh bien ton

tai 0 Ha Nam, bai Nha Mac, Vu Yen, Dinh VO, nam Thuy Nguyen.
Mao Khe - Uong Bi, Yen Lap, r~a nam Quang

Can 0

Yen, ria tay Cat Ba va phan

Ion vinh Hl;! Long la che dO dam my su vet. Vinh Cua Luc la mot ho nude
man Ion va 'veri ria cung phat trien

cac bai my su vet, Vao cudi thoi gian

nay c6 su thoai lui cua duong bo ra phia bien va thu hep dien tich cac vinh
bien ven bo do toe dO dang nude chart tinh da giarn han chi can khoang
Zmrn/narn.
rnrn/narn

Trang

khi d6, tee dO nang kien tao 0 cac khoi nang dat 2,2-2,4

[11]. Qua trinh

lang dong tram tich cOng g6p phan

lam ndi cao

dia hinh be mat tich tu tren rnuc bien trung binh. Trang qua trinh bien lui,
he de cat co thu nhat duoc hinh thanh
Quang

Yen - Thuy Nguyen,

cao 4,5-7m, chay qua Hoang

cau tao tu cat nho, trung

bien [5]. Be mat he de nay bi phong

h6a laterit

chua vo than

Tan mern

va bi he de cat Holoxen

muon phu tren [9].
Do dac diem

dia hinh, truong

gio va song tay nam tao dong boi tich

doc bo uu the tu phia tay nam (nguon
anh huong

goc song Hong)

cung cap vat lieu,

den Cat Ba, Yen Lap. Vai tro cua s6ng kha Ion tao nen nhieu

tich tu bai bien, doi cat noi dao. Thuy trieu co do Ion 2,5 - 3m c6

y

nghia

phat trien rno rong cac bai trieu thap tuong bien chua nhieu vo than mern

va cac bai trieu lay chua nhieu di tich thuc vat ngap man.jihgfedcbaZYXWVUTSRQPONM
3. G iai doan 3

Moi truong

dam lay luc dia ven bien uu the VaG khoang

truce (cuoi Holoxen

giua). Vao giai dean nay, c6 su ha thap tuong doi muc

bien 0 ven bo dong bac Viet Nam

0,3mm/nam,

204

trong

4-3 nghin narn

[6,9]. Tee dO nang chan tinh chi can

khi d6, to c do nang

k ien

t<;10

0 cac khrii na ng dat


2,4mm/nam. Su nang cao be mat dia hinh dan den hien tuong phong h6a
latcrit be mat cac tich tu c6 truck. Cau true tang van h6a va P.,l co mat cua
lua nude !rong lop van hoa 6 di chi khao co Trang Kenh v~ su phat-:-· · ·
di tlc'h ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
trien phong phu cila' cac di chi van h6a H~ Long

6

cac dao, ven bien cfmg· '

chung minh cho qua trinh luc dia h6a ven bo Dong Bac VaG khoang 4-3

nghin nam truoc [3,4].
Trang hoan canh d6, xuat hien rong khap moi truong darn lay ven bien
tren khu vue trung tarn cua VCS Bach Dang va ria vinh H~ Long.

o VCS

Bach Dang, darn lay phat trien e phia dong cua dong bang Chau tho song
Hong tudi Holoxen giua, chu yeu tren dia phan doi sut ha kha manh trong
Holoxen. Tram tich'·tuong darn lay moi truong nuoc nhat-lo kha phd bien e
cac 10 khoan Hon Xoai, ria Cai Vieng, Cat Hai, Dinh Vu, Dong Hai.
Chung chua nhieu mun ba thuc vat, nhung lai khong gap ph an hoa thuc vat
ngap man, di tich trung 10 va than mem bien. Di tich tao silk cung chu y€u
la dang luc dia, hiem cac dang bien [10]. Dieu nay chirng to moi truong it

b ria phia tay VCS Bach Dang phat trien moi
chiu anh huong cua bien.edcbaZYXWVUTSRQPONMLKJIHGFEDCBA
truong chau tho.
2. Thai

kY

thu hai

Thuoc Holoxen muon, khoang 3 nghin nam den 5-7 tram narn truce.
Su dang cao muc nuoc duoi chan tinh van rat quan trong nhung tdc do
giam. Vai tro kien tao, nhat la chuyen dong nang e cac doi kien true nang
tham gia c6 tinh quyet dinh trong tuong quan ngap chim - ndi cao. Qua
trinh lang dong tram tich voi tdc do dang ke, den bu lai ngap chim. Do uu
the boi tu, ngay ca khu trung tarn VCS Bach Dang noi ha lun kha manh,

cung duoc boi tu ndi cao tren muc bien trung binh.jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCB
1. G iai doan 1

Moi truong vinh bien, vung bien uu the VaG khoang 2-3 nghin nam
truce (dau Holoxen muon). Day Ia giai doan bien Ian tro lai, duong bo di
chuyen ve phia luc dia, vinh bien Vti Yen e trung tarn VCS B~~h Dang
xuat hien tro lai. Vinh H~ Long va vinh Cua Luc me rong, Duong bo co
ban cua dot bien Ian cung chi ap sat dai doi nui va he de cat co 1 e Hoang
Tan, Quang Yen, 'Nui Deo. Vinh Vu Yen phat trien tren nen cac ddi kien
true ha lun va nang yeu. Vinh c6 day nong, thoai, lang dong cat bot chua
nhieu vo than mem bien tuong trieu thap va duoi trieu. Moi truong nuoc
bien man to va chiu anh huang cua khoi nuoc song, dO Ion trieu co 3-3,5m.

, 52-Ccr ..TI

205


Vinh bien ban dau chu yeu chiu

S\1

tac dong cua truong s6ng huong tay

nam va VaG cu6i giai dean cua s6ng huong nam. Vinh H~ Long phat trien
tren nen nang yeu ve kien tao, nhung ngap chirn do dang chan tinh.

.

Day la thoi gian trung tam VCS Bach Dang ha lun kha manh ve kien

tao, toc do O,2-1,2mm/nam, can ngap chim do chan tinh chi O,3mm/natn.
Cac khu vue Yen Lap, Trang Kenh ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
va tay bac Cat Ba nam tren cac doi kien
true nang kien tao, toe dO nang trung binh O,6-0,8mm/nam, Ion hon toe dO
dang chan tinh [11]. Vi vay, be mat dia hinh tich tu van nam cao tren muc
nuoc bien trung binh.
trinh cling tuong tu.

0

ria vinh Cua Luc va ria bo vinh H~ Long, qua

0 nhung

noi nay, sudt giai dean phat trien cac bai Iay

.ngap trieu cao phu dac su vet. Cu dan co Viet Khe 0 phia bac Thuy
Nguyen va cu dart co Phuong Nam 0 nam Uong Bi song VaG cudi giai doan .
. Moi truong song del g6p phan hinh thanh ~~p quan dung mo thuyen chon
cat nguoi chet trong vung dam tay bien.
Cling trong giai doan nay, tich tu cat do s6ng del hoan thanh lien ket
Do SOn thanh mot dao duy nhat va noi lien nui Doi va nui Thuy Huong 0
Kien Thuy theo kieu "noi dao''. S6ng bien del tao nen cac bai cat bien, nay
la them bien bac I cao 3~3,5m 0 Do Son, Cat Ba v.v. Nguon boi tich cat
nguon goc song HOng dua tir phi a tay nam len del tao nen he can cat thu
hai cao 3-3,5m phat trien lien tuc tit Hoang Tan (Quang Ninh) den Minh
Due (Hai Phong) [5]. Vao cuoi giai doan, xuat hien moi truong bai bbi
chau tho ngap trieu 0 ria phia tay, tay bac vinh bien Vu Yen.

0 dong

nam

Cat Ba, cac ran san ho phat trien tro lai.jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
2. G iai edcbaZYXWVUTSRQPONMLKJIHGFEDCBA
doan 2

Moi truong vung bien uu the. Vao khoang 1-2 nghin nam truce (giua
Holoxen muon). Cac khu vue dong nam Cat Ba, H~ Long, Cua Luc it bien
dong va chu yeu ton tai .duoi che dO vinh bien duoc thiet lap tu truce.
Nhung bien doi sau sac xay ra 0 VCS Bach Dang voi su phat trien rong rai
moi truong vung bien (lagoon). Vung bien duoc ehe chan boi quan daoda
voi Cat Ba 0 phia dong, h~'thong de cat thu 3 keo dai tit Phu Long - Cat
Hai sang Dinh vo, Trang Cat, Ngu Dean, Tien Thang 0 phia bien.

0

phia

tay nam vung bien giap dong bang chau tho song Hong dang boi tu mo Ian

ra bien.
Truoc d6, cac bai trieu lay su vet chi han Fhe 6l;>ac Thuy Nguyen (vung
Trang Kenh) va vung Yen Lap, nay phat trien rong khap sau he de cat

206xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA


chan thu 3. Su hinh thanh

dai de cat cao 2-2,5m

nay danh

d~u mot giai

doan dong bbi tich doc bo nguon gdc song Hong tir tay nam len kha phong
phu. Dayla

Ian thu hai trang

Holoxen,

duong bo mo rong ra phia bien va

bien lui b VCS Bach Dang. Day la kieu bien thoai do boi

11:1.

Thoi giannay,

6 c~c doi kien true nang,
toc do dang chan tinh da dat den O,6mm/nam.ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFED
toc do dang kien tao trung binh O,6-0,8mm/nam.
Vi v ay va n.x ay ra n a ng cao
O-O,6mm/nam),

d ia h in h ,

6

tharn chi dat 3,lmm/nam.
do i n an g d ie u hoa

(nang

0 doi

xay ra qua trinh boi tu phat trien ndi cao, mo rong.

.S\,1th a VCS Bach Dang, mac du toc do ngap chirn tong hop O,6-0,8mm/nam
nhung toe dO lang dong O,6-1,Omm/nam

va ket qua la xay ra qua trinh S\,1t

ha c6 den bu, boi tu Hin ra bien [11]. Vinh H~ Long tiep t\,1Cton tai la vinh

,

bien do narn tren doi nang dieu hoa nhung

c6 tdc do dang chan tinh vuot

qua tdc do n,ilng kien tao, trong dieu kien nguon cung dip boi tich it va toc
do lang dong tram tich thap.
Trang Holoxen,
moi truong
dung
truong

khong

man

day la Ian thu hai ph at trien rong khap dam tay su vet,

I". Co

che boi tu trang vung bien la lap day, toc dQ thang

Ion. Vi vay, tram

khu, yem khi,

tich chua

dieu kien thuan

t<;10

luong

mun ba huu co cao, moi

l"i tich tu luu huynh dang khu c6

ham luong cao trang tram tich [2]. Tram tich dam lay bien bun bot c6 mau
xarn xanh rat d~c trung
tuong

doi rnuc bien

phd bien rong khap. Day cung la giai doan vi tri

- duong

bo ha thap

tuong

doi nhat

trong

Holoxen

muon. Vao cuoi giai dean xay ra tran chien Bach Dang Ian thu nhat (938),
sat ngoai cua Nam Trieu bay gio [11].jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
3. G iai doan 3

Khoang

1 nghin

den 5-7 tram

narn truce.

Trang

giai doan

nay, muc

0

nuoc dang chan tinh c6 toe do tang dan, trung binh gan Irnm/nam.

vinh

H~ Long. Cua Luc tiep t\,1Cton tai va mo rong vinh bien do luong bbi tich
lang dong

khong

Ion.

0

VCS Bach

Dang,

anh huong

cua bbi tich song

Hong rat Ion, cung cap doc bb tir phia tay nam len, tit cac nhanh

song ndi

ngang giua hai h~ thong song. Vi vay, chi trang thoi gian ngan, moi truong
vung bien chuyen

h6a thanh

cua song chau tho voi cac bai ngap trieu cao

tich tu bun bot set mau hong,

nau xam day O,2-0,5m phu tren

tram

xanh dam lay bien. Tai day, ngap chim tong hop dat 1-1,2mm/nam

tich

nhung

duong bo van tiep t\,1Cboi Ian ra phia bien do qua trinh lang dong tram tich
vuot den bu va bien thoai do boi tu. Vao cuoi giai doan nay, he de cat thu

207


4 cao 2,5-3m

a phi a tay nam VCS Bach Dang keo dai tu Bang La - Dai

HOp sang Hung

Thang

(Tien

noi dao ponmlkjihgfedcbaZYXWVUTSRQPONMLK
DoSon voi dong bang chau

Lang)

tho vira ~(} rong va tir day xuat hien ban dao Do Son. Day la giai doan duy
nhat cua VCS Bach Dang ph at trien cau true chau tho, hoa nhap voi dong
bang chau tho phia tay nam. Cung do anh huang

ves

due, nhat kha manh

tu

Bach Dang cac ran san ho dong nam Cat Ba (ria vinh Lan H~) phat

trien han che va phu sa nguon gdc song da boi dap len lop mat cua cac bai
trieu su vet rong Ion (} ria tay, tay bac dao Cat Ba, khu vue Hoang

Tan, Ha

An.
Co nhieu tai lieu lich su da noi ve hoat dong cua con nguoi (} khu vue

trong giai doan

nay: Cong trinh

Bang a Kien Thuy
nha Mac (Kien

de dao Ha Nam (thoi kY - Le), cua Dai

(thoi Tran), bai Nha Mac (Yen Hung),

Thuy),

khu vue Pha Rung,

Dac biet tran thuy chien Bach Dang nam

Song Chanh

song Bach Dang nong,

De Chari Kim

xay ra trong

moi truong

chau tho, long

hep hon hien nay, phu hop voi nhung

Nguyen Trai trong "Du dia chi" viet tir the ky
3. Thoi kY thu ba, khoang

xv

1288 a

mo ta cua

[11].

5-7 tram nam qua (tan cu6i Holoxen

muon)

Day la thoi ky ngan, chi ,gom mot giai doan dang tiep tuc voi m9t dot
bien Ian moi va duong bo bi ddy lui ve phia due dia kha nhanh
Dang. Nguyen
- M\1c

nhan co ban cua qua trinh nay la:

nude

O,5-1,Omm/nam

bien

dang

ch a n t in h n a n g k h a nhanh,

khoang

trong nua thien nien kY qua. Muc nude bienthe

the gioi qua dang 1,5mm/nam
thay trong

a VCS Bach

1957-1991

gidi trong

[11]. So lieu thuc do tai tram Hon Dau cho

muc nuoc bien

trung

binh

dang cao ,2,24mm/nam

[1~].
- Tuong

ung voi su dang eao cua muc nuoc bien, bien lan, thuy trieu

kieu nhat trieu deu, do Ion jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
eve dai dat 4-4,5m tro thanh dong luc uu the c'
yen bo dan den tang cuong phan tan boi tich va ddy manh xarn thuc xoi lc.
- Tinh trang

thieu

hut bbi tich dan den ngap ehim khong

tich phd bien tren vung nghien

cuu. Co nhieu

19

den bu bbi

do dan den thieu hut boi

tich. Khi ban dao Do Son ndi lien dong bang vita boi Ian da ngan khong
eho boi tieh doc bo tu tay nam di len. Trong
nhanh ngang ndi song Hongvoi
giam nguon

he 'thong

boi tich bo sung. Thuy trieu

Dong chay tong hop yen bo huong

thong

qua trinh

phat trien,

song Cau - Bach Dangbi

nhieu
tan lam

Ion da phan tan boi tich xa boo
tri DB-TN

208xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

co xu huong

dua bbi


tich xuong phia tay nam va tao din bang am cho khu V\lC.
Trang khi do, ngoai nang cha{ninh

manh len, sut ha kien tao 0 cac doi

ha lun tang len va cac qua trinh nang yeu di 0 cac dci kien true nang. VI

vay, qua trinh ngap chim tuong ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

doi khong chi xay ra 0 cac doi sut ha ma ca
tren cac ddi nang dieu hoa va cacdoi

nang kha manh. Trong boi canh do,

cau true hinh pheu voi bai trieu Jay su vet phat

VCS Bach Dang bien thanh

mang day dac voi hai nh6m,

trien mo rong, cac lach trieu phat trien thanh

7 cap [8]. Tai day, qua trinh x6i 10 uu the so voi boi tich mo rong. Vinh Hi,1
Long va Cua Luc hoan toan khong chiu anh huong cua phu sa song Hong,
nuoc tro len trang xanh. X6i 10, xarn .thl,lc mo rong dien tich cling rat phd

.

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D _ 5000- $000
B in 6i~l7g

1
2

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C ./f Ii.;'

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14

Hinh 2. Cac mat cat tien h6a dja chat Holoxen Yen Lap - Cat HM.

S"HTT.:15

). 9


bien 6 hai vinh nay. Q;.ria phia bac Cat Sa, phia nam Hoang
quanh

dao Tuan ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
C,\1;g~:,c6 the nhan thay cac ba i trieu thap rong

mongo Ve nguon
su vet.

Tan, xung

0

g6~\;h(mg

meng

duoc tao len do xarn thuc, x6i 1('1 bai trieu Jay

khu vue dong nam Cat Sa, thuoc vinh Lan H~ tai phat trien kha
dfiu hieu thoai hoa ran gan day chu

manh cac ran san ho vien bo. Nhung

edcbaZYXWV
xwvutsrqponml

q
f

2

-

-------_-_-_-_-_-_-_-

2

-

f

- -=:....-=::..-::.=-~~-::.=.:-=-=::.=-== ,
8

•.• : • : • : .: ~••• :~~ 10MLKJIHGFEDCBA
•••••

~ ••

:.

12

14

Q

-I

2
0

2
4

0
8
fO

11
14

14

2

I. PLEIXTOXEN:

3

4

5

1

G

8

9

10

1. T1I6ng song bicu (chau tho) (amOn?);

11

12

II. HOLOXEN

2. Tuong aluvi song thoi gian som (aOlyl-2); J. Tlf6ng dam ho, thoi gian
5.

som (lbO(V I- 2 ); 4. T1I6ng dam lay bien va bien xeu ke, thai gian giua (mbO(yl-2);

sorn-giira:

T1I6ng bai bien. thai gian giua (mOlyl-2);
(mQly'-2);

6. Tudng de eat bien thai gian gi\ta

6_ Tuong ho dam lay vcn bien thoi gian muon (IbQlyl-2);

HOLOXEN

muon: 8. Tuong bien trieu tMp va can duoi trieu thc)j gian som (mOly3);

de cat bien thoi gian som giua (mOly3a-b);
som-giua

(bOly3a-b);

9. Tuong

10. Tuong dam lay bien thoi gian

11. Thuc v~t ngap man; 12. Thuc vat dam lay; Om. Ml!C bien

trung binh hien nay; MAX. Muc bien eo cao nhat; MSL. Ml!C bien co trung binh;
MIN. Muc bien co thap nhat.
M in h 3

• 10


yeu lien quan den cac tac dong nhan sinh. Cung voi qua trinh
qua trinh Jay h6a cac bai trieu cao va hinh thanh

bien Hin la

nen tharn rung ngap rruin

day d~c.MLKJIHGFEDCBA

vA. nu

IV . M O T

BAo

Dua van d~c diem

phat trien dia chat Holoxen

ket hQP voi phan tich

cac qua trinh dong edcbaZYXWVUTSRQPONMLKJIHGFEDCBA
I\1C hien tai, co the dua ra mot vai du bao ve xu the ponmlkjihgfedcbaZYXW
phat

trien khu vue nghien cuu trong tuong lai[11].
- Trong dieu kien thieu

hut boi tich, toc do dang cao muc nuoc bien

chan tinh tang len, qua trinh bien Ian xay ra tren roan khu vue, Ph an tich
tuong quan dang cha~ tinh va chuyen dong kien tao hien dai cho thay qua
trinh ngap chim - bien 1:1n khong chi xay ra 0 cac ddi sut ha va nang dieu
hoa ma can 0 ria cac ddi nang kha manh. Cac vinh Lan H<;1,H <;1Long tiep

tuc ton tai, Cua Luc va VCS Bach Dang chuyen
hinh pheu (estuary)

VCS Bach

dun tir diu true cua song

sang cau true vinh (bay). Khoang

Dang bien thanh

1400-2000

narn nua

vinh bien va qua tr inh nay co the rut ngan

nhieu Ian neu du bao ve hieu ung nha kinh tro thanh

su that,

- Xoi 10 be tiep tuc uu the so voi boi tu trong dihl kien muc nuoc dang

nhanh.

Vi du, be dao Cat Hai hien tai x6i 10 4-8m/nam,

se la 8-13m /nam

co the toi da la 52-80m/nam.

xoi 10 nr 1,3m/nam

den 12,5m/nam

trong

50 narn toi

Cac doan be khac c6 the bi

[1]].

- Do xoi 10 ngang va bao man be mat, ngap chirn, cac bai dam lay su
vet b] suy giam dien tich kha nhanh.

Cac bai trieu thap duoc mo rong the

cho va sau do dan bien thanh vung ngap nuoc bien thuong xuyen.

- Cac qua trinh ngap lut ven be va nhiern man sau van luc dia se tang
len do anh huong cua dang cao muc nuoc va bien Ian, trieu truyen sau van

luc dia.

Ngoai

xu the tu nhien,

hoat dong con nguoi co the tac dong gay r a

nhung thay doi nhat dinh va trong mot vai truong
trinhtu
TAl

hop lam tang nhanh qua

nhien.

L ie u

THAM

KHAo

1. N guyen C an jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
va nnk, 1994. Hoar dong dirt gay hien dai vung Hai PhongQuang

Yen. Tai nguyen

va Moi truong

bien T.II - Nxb. KH & KT Ha

Noi.
2. N guyel/ D tlc C Lf. 1991. Mot s() dac diem dia hoa tram tich rung ngap man

211


ven bien Mien'B~c

Viet Nam. Tai nguyen va Moi truong bien T.I, Nxb

& KT Ha N oi.jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
-, KH ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

3. edcbaZYXWVUTSRQPONMLKJIHGFEDCBA
N guyen K im D ung, 1990. Di chi

xuong Trang Kenh (Hai Phong)

qua hai

Ian khai quat - Khao co h9C N°3.
4. t:lglJ;y~n:':V anH ao, 1986. Thoi ky tien su tren dao Cat Bu. Khao co -hQc so

2.
5. D inh. V an H uy,

tm «

Hai Phong - Quang

D ue Thanh, 1994. S\1 phat trien duong bo 0 khu V\1C

Yen trong Holoxen

qua nghien cuu cac he de eat co.

Tai nguyen va Moi truong bien t~p II. Nxb KH & KT Ha Noi.
6. N guyen N goc, 1984. V e mot so su hien dia chat ky Thu tu d y~g

hai va hai dao Quang

Ninh - Hai Phong, Nhung

duyen

phat hien mdi Khao co

hoc narn 1984.
7. Shepard F.P., 1964. Submarine
York, Evanston

geology.

Harper

and

Row Pub.

New

and London.

8. Tttm D ue Thunb va nnk. 1991. Hinh

thai, cau true va tien h6a cac bai

trieu lay ven bo phia bac Viet Nam. Tuyen tap bao cao HQi nghj khoa
hoc bien toan quoc Ifill thu III - Ha

9. tn« Due Thanh, 1991. Dau
Holoxen

giua - dau Holoxen

nguyen va Moi truong

j

oi.
muc nUDC van cudi

hieu ve dQt ha thap

muon d ven bo Dong Bac Vi~t Narn. Tai .

bien. Nxb. KH & KT Ha N¢i.

10. Iran D ue Thanh, 1993. Cac phuc h.~ sinh thai tao silic (Diatomeae)

trong tram tich D~ tu vung trieu Hai Phong - Quang
hoc. DHTH

Yen. Tap chi khoa

Ha Noi, so 1.

11. tm « D ue Thanh, 1993. Tien h6a dia chat vung cua song Bach Dang
trong Holoxen,

torn Hit luan an Ph6 tien sy, Ha Noi.

12. N guyen N goc Thuy, Bid D inh K huoc, 1993. El-Nino

warming

and the. sea level in, the sea of Vietnam

Nat. Seminar
Proceedings

212

on Reseach
of Vietnam

and management
IQC Hanoi.

Phenomemen

and Bien Dong

of Vietnam

coastal

gobal
sea.
zone.