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

OCi billu hi~n 'n-arig ha kiEin tao tudng doi trong giai doan hien dai Ranh giai dai nang ha tudng deli mann trong Holoxen OuClng dAng tr] bien do nang ha kiEin tao O~lt gay thuan vach n

lRUNG TAM KHOA Hoe TV NHIEN

VxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBAA eONG NGHe Quae GIA VI~NMLKJIHGFEDCBA H A l D l 1 0 N G H O C

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T~P I I I

NHA XUAT BAN KHOA HOC vA KY THU~T

HA N()f - 1997

,

13 N guyin D tic V inh, N guyin van Luong.xwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

Nghien cuu dl:lc diem song dia chan phan xa tiJ dut gay truoc gU<Jnghi trenedcbaZYXWVUTSRQPONMLKJIHGFEDCBA m ii

14 N guyin N goc, Trim van H o a n g , 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 V an 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 o iin , D ao Thi M ien.

Sinh dia tang va dl:lc diem hoan canhponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBAdl dja Iy khu vue gieng khoan BH2 (bOn

trung CiJu Long them luc dia Nam Vi~t Nam) 169

17 Triin V an H oang, D olin Lf Thanh.

Phan vung dieu kien dia chat cling trinh vung ven bien Nam Trung Bi) 186

18 N guyin The 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:lc diem phat trien cua khu vue ven bo DO S<Jn- H~ Long trong Holoxen 199

20 N guyin tu « tuu,N guyin van B ach, N guyin H uy P hU 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 ie n H tii, N guyin van B ach

Dl:lc tinh bien d(jng cua cac dai cat ven bien mien Trung (Quang Binh - Binh

22 N guyin V an N hiin, N guyin van B ach, N guyin Tien H ili, N guyin H uy P huc.

Dl:lc diem phan b6 cac tram tich tang mat bien mien Trung 234

23 U X utin H O ng, P ham V an N inh, ts van Thanh, N guyJn The tu», N guyin H o a n

Hien trang xoi liJ biJ bien Vi~t Nam va xu the phat trien cua no 243

24 D oan V an H ung.

25 B ui 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

26 N guyin N goc, N guyin H isu C it, H a V an C hien.

Cac di tich Foraminifera trong tram tich bai bien dao Nam Yet quan dao

Truong Sa (Vi~t Nam) vaynghia 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 va Kuala Pilah, Malaysia 278

D~C D I E M P H A T T R I E N C U A K H U V t ) C V E N B O

00 S O N - H J : \ L O N G T R a N G H O L O X E N

T ra il jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA D u:c Thanh, N K u yh l C a ll , D {iIlK D ire N K a

G E O L O G I C A L D E V E L O P M E ! N T O F C O A S T A L

C O S O N - H A L O N G A R E A D U R I N G H O L O C E N E

A s a result of co m b in at io n of e ust a tic sea level change, t ect onic

"m ovem ent and sedim entary process, the H olocene geological developm ent o]

studied area is divided i!110 three periods They ure begun by a transgression

or all ingression w ith the shoreline m oving landw ard and ended hy 1I

regression w ith the shoreline m oving seaw ard The period can he divided into

tile stages w ith the characteristic sedim entary environm ents.

- The first period (early - m iddle H oloccn ) consists o] three stages.

-+- E arly H olocene - beginning o] m iddle H olocene: C oastal plain, lakes

and restricted hays.

+ M iddle M iddle H olocene: Lagoons and hays w ith m ost expansive sea

area.

+ Late m iddle H olocene: C oastal sw am ps, lakes and restricted hays

- 'The second period (late H olocene) consist o] three stages.

+ E arly late H olocene: expanded hays and lagoons

+ M iddle late H olocene: expanded lagoons and hays.

+ Late late H olocene: delta, estuaries and bays.

- The third period (latest H olocene, about 50{)-700 past years) has just

been begun and consists o] one stageonly w ilh the characteristic sedim entary

environm ents of estuaries and bays.

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

199

F rom the obtained data, a few predictions or coastal developm ent o]' this area edcbaZYXWVUTSRQPONMLKJIHGFEDCBA ill the [uture w as given.ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

*

* *MLKJIHGFEDCBA

Khu vue ven• hi) D() Son - Ha Lonu• ••••. bao uom••• • mot s6 don• <' vi diu true dia•

Iyco ban I~Ivung cua song (VCS) Bach Dang (ke' dl vung Yen Lap), vinh H<;I Long, vinh Lan H~I va vjnh Cua Luc Day la mot khu vue trong diem

Holmen la mot trong nhung co Sl) khou IH)C het sue quan trt.~ng can duoc

qua n tarn Ba i vie: nay duoc d ua V~IO ket qU~Ingh ien cuu khao sat nhie u narn cua t0p the t{IC gi~1 tre n Cl1Sl~phan tich V~It{)ng hop cac tu lieu ve c() sinh dia tang, khao cll, tram tich dja rnao tfln kien t~1O va kien tao hien dai

V~I Sll dung tu lie u dew dOng IlWC nunc chan tinh [7) del Cc1 dip duoc chung

IIIinh I ~I ph II h l) P V l)i k hu v uC [I I).

I I K H A I Q U A T V E D~C D I E M P H A T T R I E N D I A C H A T K H U V l ) ' C

T R U D C H O L O X E N

Tu Oligoxen, khu V~IC nghie n CCIU huck V~I() hout dong kien tao tich cue

cung voi hout u(1ng trt) lai cua he th()ng dut g,ly sflu Song Hong, TienYen

true ne n e p cue da iphuorig cJ vi tuyen va h~ thling dut gciy chu dao TB-DN

hoar dOng truot btlllg trai Chuye n dong kh{)i tang d,I hinh thanh trung diu

hao Nengen Cua L~lC oi khCing che boi cac dut gay {I VI tuyen. o ven YCS

Bach Dtlng, da hinh tha nh -:{IC de)i nung phia hac, tuy nam va dong nam

bao qua nh vung sur ha tuo ng drii Trong pharn vi sut ha tuong deli, phat trie n m(11 v(mg dia hao doc true dut gay Kinh M C )n - Hai Phong huong tay

hac dC)ng narn Chuyen dOng k ien tao yeu dan, tro le n yen tl~h vao cuui Plioxen sorn - Plioxen gilla Mot be Ill~lt san hang moi hinh thanh, sau nay

bi nang cao, chia cat thanh cac d()i nui thap cao Jon - 250m [J,ll] Vao Plioxen muon - D~ Tu, hoar de)ng k ien tao manh len voi truong ung slJat_ co true ep nen C~IC dai phuong cJ kinh tuyen 0 phun ray narn va a VI tuyen phan

dong bac khu vue C~IC dut g<ly chu dao huong TB-DN deu truot bang phai

H~ dut gay Nui Deo - Do Son ClJ vai tro quan trong trong binh do chuyen

Oai kiEin true nang trong tan kiEin tao

va kiEin tao hien dai

Oai billu hien nang di'eu hoa trong kiEinxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

tao hi en dai ~.

OC)i billu hi~n 'n-arig ha kiEin tao tudng

doi trong giai doan hien dai

Ranh giai dai nang ha tudng deli mann

trong Holoxen

OuClng dAng tr] bien do nang ha kiEin tao

O~lt gay thuan vach ngi\.n chi' huang

earn cua mM truot

out g~y sau, heat dong trong giai doan

tar) kien tao va kiEin tao hien dal c6

bieu hien dong dift rnanh

"

Phudng truot cua dUt gay trong pha

Oligoxen-Mioxen (P 3-Nl)

Phudng truct cua dUt gay trong pha

Oliqo xen-De tu (N2-Q)

.A-" kiEin tao va kiEin tao hien dai co billu hien dOng d§t trung binh cao

Out gay heat dong trong giai doan tan

~ kiEin tao va kiEin tao hien d~i co billu hien dong d§t trung binh th§p - Out gay tan kiEin tao va kiEin tao hien - d1;l.ic6 bi@u hi en dong d§t yEiu

o o

Chan tam dong d§t dat 2,5-3 dO Richter

Ch§n tam dong d§t dat 4,1-4,5 dO Richter

oCh§n tam dongedcbaZYXWVUTSRQPONMLKJIHGFEDCBA d § t dat 4,6-5,0 dO Richter

o Ch§n tam dong d§t dat 5,1-5,0 dO Richter

Hinh 1 So do kien true tan kien 1(;10 kien tao hien lli;li

va bieu hien dia chan vung dCa song Bach Dang,

201

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L\IC

I

Vinh H<:I I DN Oit B1I

I Long I (Lan H<;t)

dong khoi tang hien dai 0 phan tay nam dut gay thuan a vi tuyen c6 mat

truot hudng nam lien ket voi cac dirt gay phuong DB-TN chuyen dich phai

Su dich chuyen nguoc chieu cua he dut gay cung phuong DB-TN hai ben

true dut g~y Nui Deo - Do Son da t<;10ra co che tach gian va hinh thanh

ne n dia hao hien dai 6 trung tam yes Bach Dang (h inh 1)[1]: Trong

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

tich cuoi, cat aluvi day den 30m Vao cudi Pleixtoxen muon c6 mot dot

bien tien t<;10nen phuc he tram 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~CMLKJIHGFEDCBA D I E M P H A T T R I E N V U N G V E N BO,D O S O N - H A L O N G

C dc giai doan phdt trien cua khu V lfC yen birDo Sun - H a Long trong H oloxen ,"

dO<:ln

VCS B<;tch Dang

I dia cuoi giai doan

Luc dia, phan I

I

vinh hep van !

cuoi giai doan

i

I

Vinh bien

(TOng nhat)

Vjnh

bien-v\lng bien

Vinh hien

(Tong nhat)

Vinh hi en

(Tong nhat)

Holoxen

3

I

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dia ven bien

!

gilla

Vinh

bidn-V\lng bidn

,

-7" :f -J ,

muon

Cu6i

Holoxen

muon

Cua song hinh

pheu (mo Tong)

Vinh kieu est uaTY (mo Jong)

Vinh hicn (mo

Tong)

Vinh hien

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

Holoxen duoc ehia lam 3 tho: ky.ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBAMoi thoi ky thu nhat va thu hai duoc

ph an lam 3 giai doan Thoi ky 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 narn truce

Bien tien chan tinh c6 vai tro chu dao doi voi qua trinh ngapchim vung

yen bo, lam bien doi nhanh chong tu moi truong luc dia sang yen bien, day

lui duong bo xa nhat ve phia luc dia Vao cudi thoi ky muc nude chan tinh

dang cham h~n, vai tro chuyen dongkien tao va tich tu tram tich duoc tang

cuong, duong bo dich chuyen ve phia bien, bien lui va vung trieu mo rong.jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

1 G iai edcbaZYXWVUTSRQPONMLKJIHGFEDCBA 4 0 f!.R I

M6i truong luc dia chuyen tiep thanh yen bien, khoang ] 1-7 nghin narn

truoc (Holoxen sorn - dau HoJoxen giua ) Muc bien cha n tinh dang rat

nhanh, tren l Gmrn/n am va ha xudng 9mm/n[uTI van ranh gioi Pleix

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

vinh Lan Ha va phan ngoai VCS Bach Dang Khoang 8-7 nghin narn truce

bien tran vao vinh Lan H~ va vung nude giua D() Son - Cat Ba - vinh H~

Long Phan Ion dien tich VCS Bach Dang van 18.d(1I1gbang luc dia yen bo,

phat trien 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 vin h bien - vurig bien, kho a ng 7-4 ngh in narn truce

(Holoxen giua) Day la giai dean bien tien Holoxen tran ng?p va mo rong

nhat tronzI:> pham• vi vung nghie n cuu Vao nua da u uiaI:> i doan., khoang

7000-5600 nam truoc, duong bo lien tuc di chuyen ve phia luc dia va ap sat

vao cac chan nui Vinh bien dune mo rorig nhung nong Tram tich duoi

trieu phan bo 0 cac bon sut ha tuong doi manh trong Holoxen 6 cac doi

con lai, chu yeu la tram tich vung trieu, g()m bai trieu thap, bai trieu Jay su

vet Bai Jay su vet thuong tao thanh dai rong phia lay, lay bac Cat Ba, bac

Thuy Nguyen, vung Yen Lap va quanh ria Cua Luc Cua Luc da rro thanh

vinh bien thong voi vinh Ht;t Long Vinh H~ Long ban chat la mot canh

dong Karsto 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 Cac

them cung dO cao kha pho bien 0 ven ria Quang 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 bo boi tu va cac doi cat ndi dao 0 Do Son, Quang Yen,

Hoang Tan,ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBATuan Chau

Vao nua sau giai doan, khoang 5600-4000 narn truoc, e6 su ha thjip

tuong doi cua muc bien va boi t1 1noi cao, rno rong Che dO vinh bien ton

tai 0 Ha Nam, bai Nha Mac, Vu Yen, Dinh VO, nam Thuy Nguyen Can 0

Mao Khe - Uong Bi, Yen Lap, r~a nam Quang 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 Trang khi d6, tee dO nang kien tao 0 cac khoi nang dat 2,2-2,4

rnrn/narn [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 cao 4,5-7m, chay qua Hoang Tan

-Quang Yen - Thuy Nguyen, cau tao tu cat nho, trung chua vo than mern

bien [5] Be mat he de nay bi phong h6a laterit va bi he de cat Holoxen

Do dac diem dia hinh, truong gio va song tay nam tao dong boi tich

doc bo uu the tu phia tay nam (nguon goc song Hong) cung cap vat lieu,

anh huong 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.jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

3 G iai doan 3

Moi truong dam lay luc dia ven bien uu the VaG khoang 4-3 nghin narn

bien 0 ven bo dong bac Viet Nam [6,9] Tee dO nang chan tinh chi can

0,3mm/nam, trong 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

di tlc'hponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBAlua nude !rong lop van hoa 6 di chi khao co Trang Kenh v~ su phat-:-· · ·

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

chiu anh huong cua bien.edcbaZYXWVUTSRQPONMLKJIHGFEDCBAb ria phia tay VCS Bach Dang phat trien moi

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.jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA

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