Paleoambientes e icnofáceis da seqüência carbonática da bacia da paraíba (cretáceo-paleogeno), nordeste do brasil

TLDR: In this article, the authors investigated the stratigraphic, sedimentological and paleontological aspects in outcrops of carbonate deposits of the Gramame and Maria Farinha formations in the Paraiba Basin.

Abstract: This work deals an investigation of the stratigraphic, sedimentological and paleontological aspects, mainly ichnologic, in outcrops of carbonate deposits of the Gramame and Maria Farinha formations in the Paraiba Basin, northeast Brazil. The objective of the investigation was to obtain detailed information on the depositional environments of these units. The Gramame Formation was deposited in a regime of highstandstand system tract, belowstand the base level of fair weather waves where prevailed conditions of soft bottom and lowstand energy, but often reached by storm events, correlated to the Cruziana ichnofacies. The Maria Farinha Formation was deposited during a regressive event, with the increase of energy and siliciclastic input, important lateral facies variation and Cruziana-Skolithos ichnofacies . The eocenic carbonate rocks, that occur in the south coast of Paraiba state, present s expressive difference from the deposits of the typical Maria Farinha Formation, and it could represent another unit. These reefal carbonates was deposited in reef-lagoon s complexes and arc se pa rated from the Maria Farinha Formation by an unconformity and, probably indicate the establishment of a lowstand system tract . The ichnofacies interpreted for them was Trypanites?. The data integration suggests a paleobathymetry of middle to inner platform (150-80m), for the Gramame Formation, and inner platform to infralitoral (60-20m), including proximity of estuaries, for the Maria Farinha Formation.

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Rcvisru Brusilcira de Gcocicucias
Jose Antonio Barbos a et et.
.1
6 ( .1): 449
-4M
. sctcm bro de 20()6
PALEOAMBIENTES E ICNO
FAcI
ES DA SEQUENCIA CARBONATICA DA
BAC IA DA PARA1BA (CR ETAC EO-PALEOGENO) , NORDESTE DO BRASIL
JOSE
ANTON
IO B
ARB
OSA', MA RIA
SOMA
LIA
SALES
V
IANA'
&
VIRG iN IO HE
NRIQ
UE NEUMANN.!
R C
SlIlII
O Estc
tmb
alho aprcscnta lima invest igac;,io d
ctalhada
dos
aspec
tos cs tratig rrificos. sc
dimc
ut
ulcgic
os c
palcontnh
i
gico
s.
priucipahncntc icnofuciologicos, e m aflonuucntos de r
och
as c
urb
..
)/J,
irieas da s for mac;ocs G ramam c c
Mar
ia Farinha. nu Bacia dn
Par ufba. nordeste do Brasil. A For mac;,io Grmn
,1Il1
C foi
dcpo
sitada em lim re
gim
e de mar alto .
abaixu
do ufvcl de base de
onda
s
de born tempo. e m ambieme de baixa cncrgi a sujcito a cvc ntos tic tcm pestade co m
predominin
de substrate ma ri o e. ic no fac ies
Cnstiuna. A Formacflo Maria Farinha. IXlr sua
vel
.• foi d
cpositada
du rante
1II11
c ven to de rcgressno. co m u
umcn
to tic c ncrg ia c
rcducilo d a lfimina d "dgua. que pro v
ocou
varim;t)cs latera is d e sua faciot ogi a e. icnofacies corrcs pon dcn tc
:1
Cruziuna-Sknlithns . a s
culc tl
no
s rcclfuls. de pro vrivel idadc
coce
nica. c ncout
mdos
nn Para fba
aprc
scnrum e xp ressive
dif
crcn ca tins calcririos da Ftlflnac;ao
Mari a Fa
rinha
tfpica.
podcndo
r
epre
sent ar
lima
outm
unidadc
. Estes calcdrins
cS
l50 scpamdos da
Formacao
Mar
ia Farinha p
or
discordancia c indicant 0 cs tabc le
cim
cnto de um traro de
mar
bai xo . c icnofacies intcrprctad a
como
71
:rl'tlllitcs'!. A intc
gr
nciio do s
dado
s sugcrc IIIna pa lcobatim
ctr
ia de plataforma int
cnn
cdiaria
a iutcrna ( I50-ROm). pam a
For
macao G runuunc. c d e pla
taform
a
imcma a infralitoru l (60 -20 m). incluindc pru ximidadc de cstudrios, para a
Formac
ao
Ma
ria Farinha.
I'
alavms -Chavc: Bac ia da Parafba. icn ofaci es. For
macao
Cramamc. Formacao
Mar
ia Farin ha
A bst rue t I'AI.AH JHNVIRONMI,
NI
:\· AN IJ ICIIN IJFACII,S OF
ttn
: CARBONATE SEQUHNCH OF I'AR
Af
BA BASIN (CRE-
TACH()U
S
-
I
'I\
U
~,()GENm
.
NE BRASIL - T his work dea ls an investiga tio n
of
the stratigraphic. se
dim
en tolo gic a l a nd paleo ntolo-
g ica l a spe c ts. mainly i
chn
olo g ic. in o ut
crop
s o f
carb
onate
dep
osit s I ll' the
Gramamc
and Ma ria Fa rinha form ation s ill the P
ara
fba
Basin. nor thea st Brazil. Th e ob
jective
o f the invest igatio n was to o btain det ailed inf
or
mation on the de pos itional en vironment s
of
these unit s. Th e Grunuuu c F
orm
ation was de posited in a regime of high standstand sys te m tract. bclo wstan d the ba se le vel o f fair
wea the r waves w he re pre vailed co nd itio ns
of
so rt bottom and lo wsta nd e nergy. hut ofte n rea ched by stor m eve nts.
cor
rela ted to the
C ruziana ich nofa cies. T he Ma ria Fa rinha Formation was deposited d uring a regre ss ive e vent . w ith the increase
of
ene rgy a nti silici-
clast it: input. impor tant lateral facies va riatio n and Cm
:h
llut-Skoli ,!lo,\' ichnofac ies
..
Th e coccnic carbo nate rock s. that oc
cur
in the
so uth co ast o f Parafba state. p resent s ex pressive difference from the
depo
sits
of
the typic a l Mari a Farinha For ma tion . and it co uld
repre sent anot
her
unit. These re efal car bo nates was
dep
os ited in re
ef
-lagoon s co mplexes and arc se pa rated from the Mar ia
luriuh
u
For ma tion by a n unco nf
or
mity and. probab ly indicat e the e stablis hment
of
a lo wsta nd sys tem truct . T he ichno facies in te rpreted fo r
them W
<l
S
'1
iYI'Wli/
C'
s'!. T he da ta integ ration sugges ts a pale
obath
ym et ry of m idd le 10 inner platform ( ISO-ROm ). for the
Gnuuam
c
Pouuatlon . and inner pla tf
orm
to infra litora l (6()-20 m). incl ud ing proxim ity o f estua ries. for the Mar iu Farinha
Fonnation
.
KL
:I ·I I'(II¥ " ·: Pa mlba Bas in. ichno facie s.
Gramame
Formation. Maria
l'arinha
f or mat io n
IN
'n{
( )I ) U
C;
,
\(
) A Bacia da Paraiba corre spond c a faixa scdi-
rncntar costeira comp rcendida entre a Zo na de Cisalhamcuto de
Pernambu co (ZCP E). nas proximidad es da cidade de Recite.
ate
o a lto de Mamanguape ao norte de Joao Pessoa (Ba rbosa ct al.•
2003) (Figura I). A bacia corrcsponde a uma tampa d istalmcn -
te inclinada que submerge suavcmcntc para lcstc, em dirccao
<1
0 Oceano Atlantico (Mabcsoone & Alhciros, 1993; Barbosa.
2004; Lima Filho et ul .• 2005 ). scndo compartimentada em sub-
bacias ou blocos. limitados por grandes ralhas do embasamenlo
Pre-Cambr iano no sentido geral E-W e NE. Dc suI para norte.
a Baeia da Paraiba divide-se nas suh-hacias Olinda. Alhandra e
Miriri
conf(m nc 0 modclo proposto por Mabesoonc & Alhe iros
(19XX
. 1991.
19(
3) e posteriormcnte modificado por Barbosa ef.
al. (200
3)(Fi
gura I).
A Bacia da Paraiba
c constituida por einco unidadcs lito-
estratignificas (F igura 2): Fonmu
;ao
Beberibc - arenitos Illivio-
lacllslrcs de idadc sanloniana'!-campaniana'! (Rcurlen. 1967a.
196 7b; 1967e; Mabesoo ne & Alheims, Feijo , 1994 ; 1993, Sou-
za.
199X); l'orm
<l
c,10 Itamarac{l - arellitos calcifcros.
f(
llhe]]Hls
carho n,itic()s
e calc,irios com silieicl,isticos de idade campania-
na-neo
-ll1
aaslrichtiana (Kegel. 1955; Lima Filho
ellll
.• 199X;
Barbosa
('f al.• 2003; Souza, 199X. 2006); Formac:lo Gramamc
- calc:irios.
margas e calc:irios margosos. ricos em micro c ma-
crofoss cis. depositados cm plataforma carbo natica media a rasa,
de idadc rnaa stric htiana (Maury,
1930; Hcurlcn. 1967a, 1967b;
1967 e; Tinoco. 1971; Muniz, 1993; Lima & Koutsouko s, 2( 02 );
l-ormacao Maria Farinha. dcfin ida por duns laciologias distin-
tas, denominadas informa lmcntc por Formacao Maria Farinha
Infe rior e Superior, A interior corresponde a uma sequencia de
calcarios argilosos e margas. similares uos depo sitos da Forma-
<;a
o G nunam e. depo sitados em ambiente dc plataforma rasa de
idade daniana (Beurlen. 1967a.
1967, 1967e; Muniz, 1993). A
F
onn
a
<;
ao Maria Farinha Superior corresponde aos calcarios
cocc nicos rccri stalizados. dolomilicos. loc'llmcntc biodctriti-
cos depo sitados em lagunas costeiras c frcntes rccifais (M uniz.
1993; Almeida. 2000) ; e FormaCao Barreiras - rcprcsentando
dcpbsitos de leqlles alliviais e nllviais. de idade plio-pleisto-
cCllica (Bellrlell. 1967a. 1967c; Mabcsoo nc
& Alheiros. 19X5.
19(3). que ocorrc m sa bre toda a
;:
irea da hacia. recobrindo de
forma discordunte as olliras lInidadcs
cret
;:ice
as e palcogcnicas
(Figura 2 ).
Nestc trabalho objetivoll-se apresentar e discut ir uma intcr-
prc
ta<;ao
paleoambi ental lias
1I1lid
ades carbomiticas. for
m<lcoe
s
Gra mamc c Maria Far inha. a pal1ir de invesligac<)es
iCllo
logi-
cas.
sedimentolbgicas e correl
n<;oes
eSlratignificas.
1\ Formacao Gramame representa
Li
ma extellsa plal
af
onna
I • PHII-
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