Geological environment of the tienyen – hacoi bay tuyển tập tài nguyên và môi trường biển, tập 10, tr 54 66 NXB khoa học và kỹ thuật

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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


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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 ,
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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

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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
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y en b o

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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

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L u u V a n D ie u

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171

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

Thi Thu

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N g u y in

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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 ,

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Thi Luu

182

349


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n g u y e n va M6i t r u a n g bien. TgpNMLKJIHGFEDCBA
x

GEOLOGICAL ENVIRONMENT
OF THE TIENYEN - HACOI BAY
Nguyen Huu Cu, Nguyen Ngoe, Tran Due Thanh,
Dinh Van Huy, Nguyen Quang Tuan,
Nguyen Va Tuan, Nguyen Thi Phuong Hoa,
Nguyen Thi Kim Anh, Dang Hoai Nhon

1. IN T R O D U C T IO N

The Tienyen
administered
in area.

ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

- Hacoi Bay, located

by the Quangninh

The bay

Northeastward

in the

Northeast

of Vietnam

Province, is over 50 km long and some 400 sq.km

is impounded

by a range

of big islands,

order, the Caibau, Vanvuoc, Vanmuc, Caichien,

which

are,

Bovang, Tieu, Dai and Dautan.

of Tiencen and Hacoi functioning

bay. The bay is rich in natural

the

It is a large coastal ~ody of

water ?y the mixture of the sea and rivers from the northwest,
two typical estuaries

in

and Vinhphuc

Islands, and connected with the sea through 5 inlets of Mo (northeastwards
Cai Bau Island),

and

which form the

as sub - systems of the

resoures, both biotic and abiotic, on which about

227,660 people (22.3% of the Quang Ninh population total in 2000) from the five
districts of Vandon, Tienyen, Damha, Haiha and Mongcai are living.
In

an endeavour to orient a sustainable

use approach of the bay, purposes of

the paper are (1) - to specify geological environment
and (2) - to devise proposals of sustainable

characteristics

of the bay

use based on the obove characteristics.

The paper has been completed by the Natural Science Council's support in 2003.

2. M E T H O D S

A N D

M A T E R IA L S

The Tienyen - Hacoi bay is considered as a-coastal
structural
54

components,

among

which is an

geosystem containing

accumulative

basin.

Integrative


T u y ln

approaches to the nature
environment

methods

v a M6i

Tai nguyen.

tr u a n g

of the bay by recording its characteristics

and identifying

of research.

tg p

problems of environmental

Materials

T iip

x

of geological

geology are the main

used to complete the paper

results of surveying physical conditions and natural

bien.

are mainly from

resources of the bay during

the years 2002 - 2003 in the NeST project conducted by the HIO.

3. GEOLOGICAL

ENVIRONMENT

STRUCTURE

3.1. Basement Rocks
3 .1 .1 . C r y s ta lin e

R ocks

The crystaline

rocks

porphyritic granodiorite,

are

composed of porphyritic

granite,

granophyre,

aplite, and aplitic granite aged middle Trias of the Nui

Dieng complex, exposed in the northwest

of the bay, Jurassic

fine - grained

biotite granite and aplite of the Pia Oac complex, 4 km north of the bay.

3 .1 .2 . S e d im e n ta r y

R ocks

The sedimentary

basement

sandstone, tuffaceous sandstone,
siltstone with a thickness
and

chert

shale,

rocks include late Ordovician - Silurian

sericite - quartz schist, tuffaceous gristone and

of 900 - 1,000m and banded siltstone,

phyllite,

sericite

schist

and

tuffaceous

claystone, clay

sandstone

thickness of 700m of the Tanmai formation, just a few kilometres
southeast

quartz

with

a

northwest and

of the bay. The Tanmai formation is covered with Devonian rocks of

the Songcau group (conglomerate,
shale and limestone),

gritstone,

quartz

sandstone,

clay and chert

1,150 - 1,390m thick in the southeast,

the Duongdong

formation (quartz sandstone, siltstone, clay and chert shale), 1,000 - 1,300m thick
in the southeast,

the Banpap formation (clayist limestone, limestone and chert),

650m thick in the south, with Triassic rocks of the Binhlieu formation (tuffaceous
siltstone,

sandstone,

tuffogenous

conglomerate

and

gritstone

of the

lower

subformation,

500 - 600m thick, rhyolite, dacite, shale and tuffaceous sandstone

of the upper

subformation,

formation
shale

800 - 1,OOOmthick) in the northeast,

(coal seams conglomerate,

of the

lower

subformation,

gritstone,
1,500

quartz

- 1,700m

conglomerate and sandstone

of the upper subformation,

southeast.

of the sedimentary

Jurassic

The upper
rocks of the

conglomerate

gritstone,

part

Hacoi formation
quartz

sandstone,

sandstone,
thick,

siltstone

siltstone

siltstone,

and

quartz

600 - 700m thick) in the

rock basement

exposed

the Hongai

around

the

is composed of
bay, which are

or clay shale of the lower

55 RQPONMLKJ


T u y in

tij,p T a ; n g u y e n

subformation,

v a M 6 i tr u o n g

300 - 750m thick,

subforrnation with a thickness

3 .2 . C o v e r in g

b iin .

T i j , p mlkjihgfedcbaZYXWVUTSRQPONMLKJIHG
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sandstone,

siltstone

and shale

of 700 - 800m [8 - 11].NMLKJIHGFEDCBA

D e p o s its

Besides the weathering

crust on the basement

rocks exposed around the

bay, the surfacial deposits are composed of unconsolidated
manifested

of the upper

along the northwest

basin. These sediments

Quaternary

shore of the bay and bottom

sediments

sediments

in the

are as follows:

- Midle - late Pleistocene
and clay with a thickness
- Late Pleistocene

aluvial - proluvial (Qll,lll)o f pebble, boulder, sand

of 2 - 6m.
marine

sediments

(m QIll)of sand, clay and fine pebble

with a thickness of 6 - 8m.
- Early - midle Holocene marine sediments
pebble with a thickness

(m Qr/,2) of sand, clay and fine

of 2 - 4m.

- Late Holocene boggy and marine sediments

(bm Q JV 3) of sand, silt and clay

with a thickness of 1 - 2m [8 - 11].
- Bottom sediments
aleurites and aleuritic

3 .3 . S u r f a c ia l

Based

include gravels, pebbles, medium and fine sand, coarse

- pelitic mud [4, 14].

S tr u c tu r e

on the

geological environment

dynamics

of geological

processes

products,

the

(GE) of the region can be divided into the following units

(fig. 1) [4] :
(1) - Coastal G E system
(La) - Coastal marine

GE type

(Lb) - Coastal water body (bay) GE type

- Inlet G E subtype
- Basin G E subtype
- Tidal flat GE subtype
. High tidal flat form
. Low tidal flat form
(Lc) - Island G E type RQPONMLKJIHGFEDCBA

56

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F ig u r e .
01
-l

1. Geological environment

structure

of Tienyen . Hacoi Bay region

><

T u y ln

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Tai nguyen

va

M6i

tr

uang bien.

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x

(2) - Land GE system
(2a) - Coastal low land GE type
(2b) - Hill and mountain GE type
The coastal marine GE type of the region is located southeast

of the frontal

islands down to some 10m deep, where the bottom is covered mainly with coarse
aleurite in a dynamic condition of seasonal longshore currents.
The coastal water body (or bay) GE type can be divided into 3 subtypes of
inlets, basin and tidal flats. All the 5 inlets are relatively narrow but rather deep,

10 - 20m, functioning as tidal channels for water exchange between the bay and
the sea. On their beds, there is almost no fine - grained sediment except for the
very coarse materials

that

may be products

during

the

erosion

time before

submerging the region. The basin subtype is shallow (2 - 4m deep) and sloping
towards the frontal islands

and inlets. Finer - grained sediments

pelitic mud) are accumulated

in the centre and midle southeast

while coarser -grained sediments
and southwest

side of the basin

(sands and gravels) - mainly in the northwest

side and even in some places, rocks are exposed in forms of

bedrock or outcrop.
(median

(aleurite and

diametre)

Finer

- grained

sediments

are coarse

of 0.071 - 0.100mm, So (sorting)

aleurite

with Md

of 1.821 - 4.494 and S,

(deviation) of 0.120 - 0.762, fine -aleurite mud with Md of 0.013 - 0.050mm, So of
2.544 - 5.809 and mlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
Sk of

0.443 - 1.029, aleuritic - pelitic mud with Md of, 0.008 0.010mm, So of 2.682 - 3.286 and Sk of 0.858. - 1.291. Coarser. - grained sediments
are medium sand with Md of 0.369mm, So - 1.685 and Sk - 1.170 and fine sand
with Md of 0.129 - 0.230mm, So of 2.102 - 3.036, and S, of 0.461 - 0.800. The tidal
flat GE subtype is large in size, mainfested in the northwest and southwest side
of the basin with high and low tidal flat forms. The high tidal flats are composed
of a mixture of aleurites,

sands, aleurite mud with organic matter, debris of rocks

and shells, pebbles and boulders. The high tidal flats stretch in a tidal range of
the mean level (2.1m) and the highest high level (4.7~), some of which are old
benches

covered

sparsely

with

boulders

and

cobbles, especially

mangroves.

However, mangroves grow well into forests on most of the flats of finer - grained
sediments. The low tidal flats, in a tidal range of the mean level and lowest low
level, are composed mainly of sands and debris of shells. Both the high and low

tidal flats have been engraved by typical digitate tidal channels and creeks .
. Belonging to the island
which are inhabited

GE type is the system of frontal islands, some of

and smaller ones in the bay. Most of the weathering crusts

on the islands are coverd with vegetation but erosion and denudation activities in
some places are active. Especially, the southeast
destroyed by waves, forming alternative
58 RQPONMLKJIHGFEDCBA

slope of the frontal islands is

cliffs and beaches.


Tuyin

The

c o a s ta l

lo w

com posed

m a in ly

of

s e d im e n ts ,

GE

e a rly

a ll o f w h ic h

in fra s tru c tu re
b a s ic a lly

la n d

-

a re

ty p e

o f tra n s p o rta tio n

d e fo rm e d

is

m id le

o c c u p ie d

by hum an

su-:

tij,p 'Tai nguyen va M6i truang

a lo n g

th e

H o lo c e n e

n o rth w e s t

and

P le is to c e n e

fo r a g ric u ltu re

and

irrig a tio n .

a c tiv itie s

th a t

and

The

have

s id e

o f th e

d e te re d

bay,

u n c o n s o lid a te d

in h a b ita n t

re lie f

Tij,p XaZYXWVUTS

by

la n d

w ith

its

d e p o s its

is

p ro c e sse s

in

th e s e

g e o lo g ic a l

n a tu re .
The

h ill

and

m o u n ta in

w e a th e rin g

c ru st

c o m m o n ly

d e lu v ia ls

season

w hy

w a s h in g ,
and

s e d im e n ts

p e b b le s , b o u ld e rs

4. N A TU R A L

G E ty p e

is n o rth w e s t

e ro d in g

and

p ro lu v ia ls .
of

th e

bay

d e n u d in g

Such
a re

o f th e

c h a ra c te riz e d

p ro c e sse s

g e o lo g ic a l

m ix e d

bay,

and

a c tiv e tie s

w ith

v e ry

a re

c o a rse

by

fo rm in g
th e

m a in

m a te ria ls

as

s y s te m

fo r

a n d e v e n c o b b le s [4 , 1 1 ].

RESOURCES

OF THE

BAY

4 .1 . L iv in g R e s o u r c e s
L iv in g

(b io tic ) re s o u rc e s

c o m m u n itie s .
23

M a n g ro v e s

flo ra a n d fa u n a

w ith

c e lll) , 7 2 s p e c ie s

4 .2 . N o n - L iv in g
- liv in g

d e fin e d

as

la n d s c a p e
th e

th e

o c c u re n c e

(a b io tic )

bay.

to u ris m ,

g e o lo g ic a l

of

o f th e

(d e n s ity

a life

is th e

th e y

- s u p p o rtin g

m a n g ro v e

cover

som e

bay. T he bay

of 10

1 1 0 s p e c ie s

3
_

e c o s y s te m
1 6 ,4 0 0

c o n ta in s

(d e n s ity
2 5 .7 x 1 0

3

o f z o o b e n th o s

h e c ta re s ,

an

o f 1 .9 x 1 0

w ith

aboundaut
3
-

7 0 .9

10

X

in d /rn " ), 5 4 s p e c ie s
and

1 8 3 s p e c ie s

3

of

a re o f

[4 , 1 3 ].

R e so u rc e s

p o te n tia ls

depend

th a t

o f p h y to p la n k to n

re so u rc e s

M ost
The
to

w a te r

o f th e

m ost

d e v e lo p
w ay

in c lu d e

v a lu e s

la rg e ly
re so u rc e s

on

its

and

m a te ria l

re la te s

- liv in g

- s a lin e
and

a base

its im p o rta n t

o f N a tu ra l

its

p o te n tia ls
k a o lin ,

tita n iu m ,

re so u re s

o f th e

a q u a c u ltre ,

e tc .)

bay

e c o lo g ic a l

fO T o ffsh o re
p a rt

fo r s o c io -

fis h in g .

a re
and

S in c e

to th e lo c a l e c o n o m y .

R e so u rc e s

u n its

c o n ta in

c o m p o s itio n

g e o lo g ic a l

and

(c o a l, iro n ,

of non

b ra c k is h

h a s c o n trib u te d

e n v iro n m e n t

m in e ra ls

m in e ra ls

tra n s p o rt,

4 .3 . G e o lo g ic a l D is tr ib u tio n

th a t

as

a re 3 0 s p e c ie s o f a h ig h e c o n o m ic v a lu e

1 9 6 0 s , a q u a c u ltu re

The

w o rk

re so u rc e s

w e ll

a re a

o f se a g ra ss,

d e v e lo p m e n t.

o c c u r a ro u n d

to ta l

o f z o o p la n k to n

5 s p e c ie s

N on

so

1 9 4 s p e c ie s

fis h e s , a m o n g w h ic h

e c o n o m ic

g ro w

fo r 4 0 % o f th e

seaw eeds,

bay

O n e o f th e m o s t v a lu a b le

s p e c ie s .

a c c o u n tin g

o f th e

and

e n v iro n m e n t

n a tu ra l
geo
u n its

re so u rc e
-

d y n a m ic s .
w ith

th e ir

ty p e s
The
ow n

59


T u y ln

tijp

T'ai

nguyen. va

M6i

t.r u a n g

properties

as shown in the Table

formations

(except the titanium

provide geosystem resources,
potentials

b ie n ,

T tip

X

1. Most of the minerals

occur in the rock

in old sand bodies) while others, substantially,

which associate different values of use, in form of

to develop local socio -economic sectors, among which are fishery and

tourism.NMLKJIHGFEDCBA

5. G E O D Y N A M IC S

Reactivated
differentially

A N D

D EV ELO PM EN T

on the Caledonite structure,

uplifting

O F

TH E

BA Y

the region is still in a situation of

for which the Tienyen

- Hacoi Bay was located in a

relatively subsiding zone between the two uplifting zone - one in the northwest
(called the Binhlieu uplifting zone) and the other in the southeast

uplifting zone). These zones are distinguished
southwest

directed

faults

and

also separated

(the Vinhthuc

by the two systems of northeast
by northwest-southeast

-

faults,

among which is the' well - known Tienyen active fault [6, 8, 9, 11] is located. The
relatively subsiding

zone is recorded as a graben or a tectonic valley into which

runoffs of the region are flowing. Due to the runoffs in one time, the inlets of the
bay were eroded to an extraordinary
The sea -

level rise

unconsolidated

leter

sediments.

depth when the sea was far from the region.

submerged

the valley

and formed

a sequence

In the latest sea - level rise (in Holocene time), early -

midle and late Holocene sediments of different origins were accumulated
appearence of the Tienyen and Hacoi estuaries,
by digitate

deep channels

the bay and its estuaries

of

whose tidal flats were engraved

and creeks. The current
are characterized

with the

endogenous

by the relative

geodynamics of
subsidence

while

exogenous processes - by the domination of the sea (tides) over the land (rivers).
The northeast

coastal area (Mongcai - Hongai) is influenced by the regular

diurnal tide with such a wide range that its level is the highest of the Vietnam
coastal zone as mlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
4.6 m in Cuaong, 4.7m in Tienyen or 4.9 m in the Changtay Island.
The runoffs flowing into the bay are very small, including Hacoi, Damha, Tienyen
and Bache rivers, in which the Tienyen River is the largest but its discharge is
0.0347 x 10 6 ton of suspended

just about 0.66 x l O"m" of waterand

solid. Though

small in size, the discharge of rivers changes so extremely with seasons that its
discharge in rainy season is 4 - 5 times higher than that in dry season. These
geodynamic

features

are

the

main

dominated

estuatries,

estuaries),

[4, 7, 12], with large

reasons

why there

defined as drowned river valleys

exist

the

two tide

-

(the first category of

low and high tidal flats of sands,

aleurites,

gravels, pebbles and even boulders, in which mangroves grow well into forests,
and why rocky shores of the bay have been deformed substantially
rocky

platforms

have

been

60 RQPONMLKJIHGFEDCBA

covered

almost

with

accumulative

and their
forms

and


T u y in

mangroves into the

ttip

Tai nguyen

v a M 6 i tr z tiJ n g b ie n .

so - called tide and mangrove

considered to be drowned sustainably

by relatively

coasts.

x

T ~ p mlkjihgfedcbaZY
ponmlkjihgfed

The bay is now

subsiding

movements,

sea

level rise and poor supply of sediments.
T a b ls

I,

Geological distribution

of natural

resources

Natural resources

Geological
environment

.

Living
Aquatic products

I a. Coastal

Non - living

Nearshore navigation, microclimatic

marine GE type
I b. Coastal water

Estuarine

body(bay)

(productive),

GE

type

and mangrove

ecosystems

Potentials

as much as

tourism, shrimp ponds in high tidal flats and

biodiversity,

30 species of a high economic value,
as

-

a life

communities

supporting

system

for

by fishing or gathering,

important

ecological

maintaining

functions

stock,

nursing;

spawning

for

potentials

conservation

for
and

natural

of wetlands

for

ecological

and

molluscan

grounds

in

impounded

by

weirs,

transport;maintaining
table;

water

faits
way
water

microclimate;

function of burying land-based

contaminant, water
self

tidal

underground

harmonizing

environment

and

low

landscape

exchange

-cleaning;

a

base

with the sea
for

offshore

fishing
I c. Island GE

Terrestrial

type

accompanied

covers

vegetation

with

potentials

faunas

for

natural conservation

Minerals

of construction

materials,

sands, kaolin, iron, coal, titanium;

crystal
function

of a rocky wall against" strong wind fronts
and high waves;
and landscape

potentials

tourism,

for ecological

swimming

beaches

inhabited

areas,

(Vinhthuc Island)
2a.

Coastal

low

land GE type

Fruit

and

including

cereal

cover,

vegetation

industrial

tree, life - stock,

Farming

soil

construction

and

sands,

titanium

In old sand

bodies

etc.
2b. Hill and

Terrestrial

moutain GE type

life with numerous
potentials

cover and wild

Diverse

species of values,

climatic

vegetation

for

natural

conservation,

minerals,

fresh

harmonization,

water

tourism

supply,
potentials,

etc.

etc.

6. SUSTAINABLY - ORIENTED
Based on the integrated
the highest

benefit

and

USE OF THE BAY

resource use of a coastal water body so as to effect

enhance

the

quality

of life but

not to cornprormse

61


T u y ln

tijp

T a i n g u y e .n

environmental

v a M 6 i tr u a n g

resources

geological distribution

b ie n .

T ijp

x

[1 - 5, 7] as well as values of the nature,

of natural

and renewal, sustainably

and on the

resources with their own properties

of reserve

- oriented uses of the bay can be proposed as follows:

---(1)Development of ecotourism with activities of visiting diverse landscapes,

especially mangrove forests, and link to the Traco, Mongcai and Halong tourist
resorts.
(2) Development

of aquaculture

in low tidal

flats

impounding the flat with bamboo weirs but restriction

of sands

in way of

of aquaculture

ponds in

mangrove forests.
(3) Development

of natural

conservation

of what

endow

local

SOClO

-

economy with direct or indirect values that include:
- The geological and geomorphological values, some of which are nowhere
to be seen, such as a system of marine terraces, a remain of a drowned
graben-shaped

valley, in which old benches and flatforms of rocky shore

are now covered almost

with sediments

and mangroves,

sometimes

mangroves only, etc.NMLKJIHGFEDCBA
- The landscape

values

emanating

from the' diversity

of relief

and

geological formations with native vegetation covers and their wonderful
sights in inner and frontal islands, hills and the innermost, etc.
- The wetland
northwest

values,

especially

vegetated

tidal

wetlands

along the

side of the bay working as a spawning and nursing ground,

visiting resort, etc.RQPONMLKJIHGFEDCBA

7.

C O N C L U S IO N

•

The geological environment
geological environment

of the Tienyen - Hacoi Bay belongs to the

type of coastal water bodies, composed of the

Paleozoic and Mesozoic rock (both crystaline and sedimentary)
covered with Quaternary

sediments and structured

basement

into surfacial units of

inlet, basin and tidal flat subtypes covering for some 400 sq.km in area.
The inlets are deep and narrow, known as a result of erosional processes
in the past, in which there is almost no newly - accumulated

sediments.

W hereas, the basin and tidal flats are large in size, resulting from the old
platform

of rocky shores submerged

and covered with sediments

and

mangroves .
• The Tienyen - Hacoi Bay with its estuaries

62

formed in the late Holocene


T u y ln

time is located in a graben
sustainably

in conditions

sediments

and

tijp

Tai

nguyen

v a M 6 i tr u im g

- shaped relative

subsiding

b ie n .

x

T i j p ponmlkjihgfedcba

zone, drowned

of the sea - level rise and the poor supply of

characterized

by the

dynamic

domination

of the

sea

(tides) over the land (revers).
• Living resources of the Tienyen - Hacoi Bay nave more values than non living resources,
indirect

the value of direct resource use is lower than that of

resource

use, the value of reserved

resources

than that of what are being used and the integrated

is much higher
resource

use of a

coastal system is the best way to effect the highest benefit.

REFERENCE
1. Nguyen Huu Cu et a1.,1994.
Geological Environment

Characteristics

Stored in the Haiphong Institute

of the Halong Bay. Survey Report,

of Oceanology.

2. Nguyen Huu Cu, Tran Due Thanh and Dinh Van Huy, 2000.

Methodology
Report

of Studying

of the

Institute

Project

Coastal

W ater

Managed

by

Bodies

NCST,

of Vietnam.
Stored

in

Component

the

Haiphong

of Oceanology.

3. Nguyen Huu Cu, Tran Due Thanh and Dinh Van Huy, 2001.
Rationale
Component
Haiphong

Use

Orientation

Report
Institute

for

of the

the

Project

Chanmay

Managed

and

by NCST,

Danang

Bays.

Stored

in the

of Oceanology.

4. Nguyen Huu Cu et e1. , 2003.
Additional
Resources

Survey

on Physical

and Environment

Use and Development.
in the Haiphong

of the Tienyen

Report

Institute

Conditions,

of the Project

Socio - Economy,

Natural

- Hacoi Bay for Sustainable
Managed

by NCST, Stored

of Oceanology.

63


T u y in

tijp

T ai ng ayen.

va

uang

M o i tr

T t i p mlkjihgfedcbaZYXWVUTSRQPONMLKJIH
X

b iin .

5. Nguyen Due Cu et al., 1994.

Survey on Tidal W etlands
Vietnam.

Survey

in the Coastal Area and Islands in Northest

Report,

Stored

in

the

Haiphong

Institute

of

Oceanology.
6. Nguyen Van Giap, Phung Van Phaeh, 2000.

Geodynamic

and

Structure

Systems in the Northesast

Characteristics

of

Marginal

Faulting

of the Tonkin gulf Contr. mar. geol. geoph.

Vol. VI, Sci. Techn. pub. House, Hanoi, p. 123 - 131.
7. Nguyen Chu Hoi at al., 1990.

Study of Rationale use of Tidal Marshes in North Vietnam. Report (vol. 1) of
the project 48B - 05 - 02, Stored in the Haiphong Institute of Oceanology.
8. Nguyen Cong Luong et el., 1999.

Geological and Mineral

Map of Hongai in a Scale of 1

200,000 and

Description. Gen. Dep. Min. Geo. Vietnam.
9. Nguyen Cong Luong et eI., 2000.

Geological and Mineral

Map of Hongai in a Scale of 1

200,000 and

Description. Gen. Dep. Min. Geol. Vietnam.
10. Nguyen Ngoe, Pham Hoang Hai, Le Due An, 2001.

Coastal Marine Islands

of Vietnam. Report of the Project Managed by

NCST, Stored in the Hanoi Institute

of Oceanography.RQPONMLKJIHGFEDCBA

11. Nguyen Ngoe, 2000.

Geological and Mineral
Component

Report

Haiphong Institute

Features

of the Tienyen - Hacoi Bay Region.

of the Project Managed by NCST, Stored

in the

of Oceanology.

12. Tran Due Thanh et el. , 1985.

Geology and Geomorphology

of the Coastal

Zone in North Vietnam.

Component Report of the Project 48 - 06 - 14, Stored in the Haiphong
Institute

64

of Oceanology.

T u y in

tg p

Tai

nguyen.

va M 6i

tr u o n g

b ie 'n . T g p

X

13. Nguyen Van Tien and Le Thi Thanh, 2002.

Living Resource Potentials

of the Tienyen - Hacoi Bay. Component

Report of the Project Managed

by NCST, Stored

in the Haiphong

Institute of Oceanology.
14. Luu Ty et at, 1969.

Geology and Landform of the Damha - Mongcai Coastal Area. Survey
Report, Stored in the Haiphong Institute of Oceanology.

TOM TAT
MOl TRU'ONG DJA CHAT VJNH TlEN YEN - HA COl
N guy€n
D in h

Van

H iia

H uy,

N guy€n

Ca, N g u y € n

N guy€n

Q uang

Th] Phuong

N goc,

T r tin

T u tin ,

N guy€n

H oa,

N guy€n

D tic

Thonh,

V ii T u tin ,

T h .i K im

D ij,n g H o a i

Vinh Tien Yen - Ha Cai 113m ot vinh
dai tren 50km va r<)ng khoanq

400km

2

,

ven bo dong bac

Anh,
N hdn

Vi~t Nam co Ion voi chieu

do cac huyen Van 8on,

Tien Yen, 8am

Ha,

Hai Ha va th] X8 M 6ng Cai quan IY·
Da m 6ng cua rnci trvong

dta chat vinh Tien Yen - Ha Cai gom cac da ket tinh

tuoi Triat cua phirc h~ Nui 8i~ng
tuoi O rdovic

va tuoi Jura cua phirc h~ Pia O ac, cac da tram tich

m uon - Silua cua h~ tang Tan M al, tuoi Devon cua he tang song Cau,

Dvong Donqva

San Pap, tuoi Triat cua h~ tang Sinh Lieu va Hon G ai, cac da tuoi

Jura cua h~ tang Ha CaL
Lop phu tren m 6ng cua rno: tnrcnq dla chat 113cac tram tfch 'bo roi c6 nquon gac
song - IG (apQ II_IlI). tram tfch bi§n (m Q III, m Q IV1-2)

va dam lay - bi§n (bm Q IV3)

voi

tong chieu day dat tren 10m .
Cau true ngang

cua m ol trvong

dla chat vinh Tien Yen - Ha Cai c6 th§ diroc

phan chia thanh cac phan v] sau:
(1)- H~ m ol tnronq dla chat vunq be bi§n
(1 a)- Ki§u rnoi tnronq dia chat bi§n ven bo

5- TTTN

ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

65 RQPONMLKJIH


T u y ln

tg p

Tai nguyen. va

M6i

(1 b)- Kieu rnoi tnronq

chao

ve

tr u a n g

bien.

T tip

x mlkjihgfedcbaZYXWVUTSRQPONMLKJIHG

dia chat thuy v u e yen bo, gom cac phu kieu cua, long

bai trieu (danq bai trieu cao, thap)

(1 c)- Kieu m ol tnrcnq

dia chat dao

(2)- H$ m ol tnronq dia chat

II,1C

dia

(2a)- Kieu rnoi trLfong dia chat dong bang thap yen bien
(2b)- Kieu rnoi trLfong dia chat doi va nui
Phat trien tren ddi sut ha tironq d6i danq dia hao gidi han boi cac ddi nanq
tuonq d6i Binh Lieu

0 phfa tay bac va Vinh Thuc 0 phfa dong nam , vinh Tien Yen -

Ha C6i la m ot thung lO ng kien t90 c6 2 vunq cira song hinh pheu dien hinh (Tien Yen

-va-

+ta C6i) b] ngcflp chim trong

bien tien Holocene,

trong d6 cac qua trinh dia chat

hien dai chira lam thay de>idang ke hinh thai kien true cua khu v u e .
Tren co so danh qia cac qia tr] tai nquyen sinh vat (dac biet la h$ sinh thai rltng
ngcflp m an), tal nquyen

phi sinh vat (d~c biet la tiem nang phat trien du lich sinh thai

nho c6 cac qia tr] canh quan va bao ton

Iy

tu nhien), c6 the de xuat hLfdng sll dunq hop

vinh Tien Yen - Ha C6i nhu sau:
(1)

Phat trien

du lich sinh thai vci cac heat d(>ng tham

quan

danq, d~c biet la rltng ngcflp m an, va n6i lien voi cac diem du lich Tra

earth quan da

ce,

M 6ng Cai

va H9 Long.
(2)

Phat trien nuoi trong thuy san tren bai trieu thap bang each quay bao bang

dang tre, han che dam nuoi trong rltng ngcflp m an.
(3)

Phat trien bao ton tu nhien,

66 RQPONMLKJIHGFEDCBA