- Dut gay Cftn Du'C1c Ba Ria FV6.
4.4 mnh thai b~ m~t mong tru'dcKainozoi: Tren cd sd ke't qua philo tich
dinh Iu'<;Ingcae du'dng eong do situ di~n, ke't h<;lpvoi cae du'dng net kie'n t<;lO theo cae tai li~u Dia v~t Iy tren di~n rQng (tu va tn;mg Ige), hlnh thai b~ m~t mong tru'oe Kainozoi vung Thanh PhO'da du'<;Iexae I~p kha chi tie't cae d~e tru'ng ma cae tai Ii~u tru'oe dily ehu'a th~ hi~n du'<;Iedo sg thie'u hl;lttai li~u, d~e bi~t Ia cae M thO'ngdut gay. Ne'u nhu' tren sd d6 hlnh thai do ehinh tae gia thanh I~p nam 1987 va tren cd sd do, Ma Cong CQ da thanh I~p sd d6 hlnh thai b~ m~t mong vung Thanh phO'H6 Chi Minh co dia hlnh kha ddn di~u, cae M thO'ngdut gay co phu'dngAvI tuye'n va Akinh tuye'n
th~ hi~n mQt caeh md nh<;lttren dia hlnh b~ m~t mong Kainozoi, thl ngu'<;Ie I<;li,tren sd d6 hlnh thai b~ m~t mong moi du'<;Iethanh I~p tren cd sd cae ke't qua xU'Iy va philo tich t6ng h<;lptai Ii~u da lam n6i b~t Ien cae du'dng net effu true theo cae phu'dng nay. Co th~ nh~n thffy dog diu true vung Thanh
phO' H6 Chi Minh bi khO'ng ehe' bdi cae M thO'ng dut gay co phu'dng Akinh
tuye'n, AvI tuye'n, Dong bAe-Tily Nam va Tay bile-Dong naill, cae M thO'ngdut gay nay da lam eho dia hlnh b~ m~t mong nang sl;lt d<;lngkhO'i tang theo phu'dng Tay BAe-Dong Nam. Theo phu'dng nay, co sg hi~n di~n r6 r~t 3 khO'inang eua dia hlnh b~ m~t mong tru'oe Kainozoi, do Ia:
- KhO'inang Cu Chi: du'<;IegiOi h<;lnd phia BAe va phia Nam bdi cae
dut gay Dong BAe-Tily Nam FDBIva FDB2.
- KhO'inilng Tan Sdn Nhfft: bi gioi h<;lnbdi hai dut gay co phu'dng Dong BAe-Tily nam FDB4va FDB5.
- KhO'i nilng C~n Gid.
Cae khO'inilng nay du'<;Iephilo caeh bdi cae hO' Sl;lt:Xuan Thai
Thu'<;Ing,Nha Be va eilng bi khO'ng ehe' bdi M thO'ng dut gay co cling
phu'dng . Trong m6i khoi nang do, co th~ co tung b~e nang h<;lmQt caeh
tu'dngdO'ikhae nhau bdi sg chi phO'ieua caeMthO'ngdut con I<;li.M~tkhae, theo phu'dng Dong BAe-Tay Nam, dia hlnh b~ m~t mong co d<;lngb~e khae, theo phu'dng Dong BAe-Tay Nam, dia hlnh b~ m~t mong co d<;lngb~e
thang do sg chi ph6i cua M th6ng dut gay co phuong Tay Bclc-Dong Nam, va M th6ng dut gay co phuong a vi tuye'n, co th~ chia thanh 3 b~c nhu sau:
- B~c Thu Duc- Gi5ng Chiia.
- B~c Cu Chi- C~n GiO.
- B~c Blnh Chanh.
KETLU!N
Tren co sd phuong phap lu~n cua vi~c gi:H bai bai toan ngu<;1ctrong
tham do Dia V~t 19, xay dl;1ngchuang mnh phan dch, xa 19 va t6ng h<;1p mQt kh6i lu<;1ngkha IOn cac du li~u Dia v~t 19 co tren vling Thanh Ph6 H5 Chi Minh. Ke't qua cua lu~n an da d~ c~p va giai quye't nhung v1lnd~ sau day:
IV ;; I ~
di.:! . e u=.tn em:
- Trong vi~c phan dch ffii li~u Dia v~t 19,dn phai nclmvung cac kie'n
thuc chuyen moo Dia v~t 19 va cac tu duy co ban v~ cac d6i tu<;1ngma
mlnh dang nghien cuu, d~ co th~ 19a chQn mQt mo hlnh h<;1p19 trong hang lo<;ltcac mo hlnh co th~ t<;lOra cac du li~u phIl h<;1pvoi cac du li~u thgc te'
quan sa t du<;1c.
- Da tri la mQt thuQc tfch c6 huu cua bai toan ngu<;1ctrong thiim do Dia v~t 19.D~ lo<;litru Hnhda nghi~m, dn phai sa dl;1ngmQt t6 h<;1pphuong pha p nghien cUu h<;1p19, nh~m ml;1Ctieu h6 tr<;1va b6 sung cho nhau trong vi~c giiii doan cac ke't qua phan tfch.
-Sgthay d6i cuong dQ phong X<;lcua cac thanh t<;lOtr~m dch la mQt
trong cac d1lu hi~u co ban trong vi~c lien ke't va phan chia dia t~ng giua
cac 16 khoan, di;lcbi~t la cac t~p tdm tfch du<;1chlnh thanh d giai do<;lncu6i cua chu ky tr~m tfch Neogen va t~ng set tren cling cua t~p tr~m tich Q(23, v1lnd~ nay dn du<;1cnghien cuu them trong cac cong trinh nghien cuu tie'p
theo. 2. Ke't qua:
- Tie'p thu cac thanh tgu cua khoa hQCva cong ngM hi~n d<;li,tac gia da xay dgng du<;1cmQt chuang trlnh phan tich tai li~u do sau di~n mQt
chi~u theo phuong thuc giao di~n trlfc tie'p giua nguoi va may tren co sd
tinh nhanh bai toan thu~n, ke't h<;1pvoi cac tu duy v~ d6i tu<;1ngnghien cuu, cho phep nguoi phan tfch 19a chQncac mo hlnh ke't qua h<;1p19.
29
- Da xay dl,fngdu<;1cban d6 dia hlnh b€ m~t mong Kainozoi vung
Thanh ph6 H6 Chi Minh tren cd sd xii'19 t6ng h<;1ptai lic$uDia v~t 19, tren do th~ hic$nkha r6 net cac d~c di~m ca'u truc cua vung Thanh ph6.
- Ke't qua cua vic$cxii' 19 t6ng h<;1ptai lic$uDia V~t 19 cling da kh~ng
dinh mQt cach cha:c cMn sl,fhic$ndic$ncua cac M th6ng dli't gay, cling voi sl,fchi ph6i cua chUngkhong nhii'ngtren hlnh thai ca'u trUc cua da mong ma
con lam anh huang den cac duang net cua b€ m~t dia hlnh hic$nd~i. Ne'u nhu hc$th6ng dli't gay co phudng Tay Ba:c-Dong Nam la Mth6ng dut gay chinh dinh tuye'n dong va giOi h~n dong chay cho song Sai Gon, thl hc$ th6ng dut gay Kinh tuye'n laM th6ng dut gay chinh kh6ng che' giOi h~n va
dinh tuye'n dong chiiy cho song Nha Be-Soai R~p. Cac ke't lu~n tren day la thong tin giup cho cac nha dia cha't lu~n giai v€ cac ho~t dQng tan kie'n t~o trong vung Thanh ph6 va cac khu vl,fcIan c~n.
- Ranh giOi nhi~m m~n cua cac t~ng nuoc ng~m theo tai lic$uDia v~t 19 co lien quail kha cMt cM de'n cac M th6ng dut gay, day la thOngtin ra't quail trQng giup cho vic$cdinh huong, quy ho~ch, khai iliac cac tai nguyen da't va nuoc trong chie'n lU<;1cphat tri~n cua Thanh ph6.
M{)t s6 kie'n nghj:
Sail khi thl,fchic$ncong trlnh nghien CUllcua minh, tac gia xin dtt<;1c pMp kie'n nghi mQt s6va'n d€ nhtt sail:
1. Tren dic$ntich Thanh ph6 H6 Chi Minh, phttdng phap trQng ll,fc chi moi dtt<;1cnghien CUllra't h~n che', d~c bic$tla con bo tr6ng d vung C~n
Gia, vic$cgiai doan mQt cach chi tie't hdn cac d~c di~m v€ kie'n t~o cua vung Thanh Ph6, ra't dn de'n cac s6lic$u trQng ll,fcva tIT,vl v~y, dn tie'n hanh cong tac do ve trQngll,fcm~t da't d~ phil kin dic$ntich vung Thanh ph6 H6 Chi Minh va cac vung Ian c~n. Ke't qua cua vic$ckhep kin dic$ntich khao sat se cling ca'p them cac dii' lic$u,giup cho vic$cphan tich ca'u truc Thanh ph6 mQt cach chi tie't hdn.
2. Dia v~t 19 Ia mQt trong cac phttdng phap nghien CUllva ung
dl:lllgkha hic$uqua trong nhi~u Hnh vl!c, d~c bic$tla cac d~ng di~u tra cd
ban, cac dii' lic$uDia v~t 19 thttang co gia tri trong mQt thai gian dai, va la ngu6n thOngtin vo cling qu9 gia. Thu tMp quail 19d~ tie'p tl;lCsii'dl;lngcho cac giai do~n nghien CUlltie'p theo la mQt vic$clam he't suc dn thie't, d~
tie'p h;1Ckhai thac trong cac giai do:;tnv~ sau. Hi~n nay, vi~c phan chia va lien ke't dia t~ng giii'a cac 16 khoan cM ye'u d\fa vao cac dc;ictntng v~: thanh ph~n th:;tchhQc, vi c6 sinh, baa tapha'n, dia t~ng..., d~c tinh phong X:;tcua cac t~ng h:;ttmill chu'a du'<;1cchU9 dung muc, dn dffu tu'nghien CUll tie'p theo ve m6i quan h~ giii'a tinh cha't phong X:;tcua cac t~ng set va b6i canh thanh t:;tocua chUng, gi:ii quye't du'<;1cm6i quan M nay, co th~ giup cho cac nha dia cha't co them thOng tin b6 sung trong vi~c s~p xe'p, phan chia, dinh tu6i va lien ke't dia t~ng giii'a cac 16 khoan.
3. Phu'dng phap tham do di~n mQt chi~u, co lich sa phat tri~n kha lau dCfi,nhu'ng de'n nay vh con nguyen gia tri khi nghien cUu cac moi
tru'Cfngtr~m tich n~m ngang. Hi~n nay, co kha nhi~u chu'dng trlnh phan tich tai li~u tham do di~n mQt chi~u (lD) dii du'<;1cxay d\fng, nhu'ng chu'a du'<;1c ph6 bie'n rQng riii. Nhi~u ddn vi nghien CUllva ung dl,lllg trong nu'DCsa d1;1ngcac chu'dng trinh phan tich khac nhau. Chu'dng trinh phan tich nhanh bai toan ngu'<;1ctrong tham do di~n 1 chieu dii du'QCde c~p trong lu~n an, sau khi du'<;1cb6 sung them mQt so' ti~n ich dn thie't, co th~ du'<;1cph6 bie'n rQng riii hdn cho cac nha ung d1;1ngtrong nhieu lInh V\fc thuQc ky thu~t tham do di~n.