Seismic Characterization of Macaé Group in Bonito Field Campos Basin – RJ (Font:
Arial bold, 12)
Ricardo Otto Rozza Schmidt UNESPETRO/UNESP Authors, Entities (Font: Arial normal, 9)
Copyright 2013, SBGf - Sociedade Brasileira de Geofísica
This paper was prepared for presentation during the 13th International Congress of the
Brazilian Geophysical Society held in Rio de Janeiro, Brazil, August 26-29, 2013.
Contents of this paper were reviewed by the Technical Committee of the 13th
International Congress of the Brazilian Geophysical Society and do not necessarily
represent any position of the SBGf, its officers or members. Electronic reproduction or
storage of any part of this paper for commercial purposes without the written consent
of the Brazilian Geophysical Society is prohibited.
____________________________________________________________________
Abstract (Font: Arial Bold, 9)
Text (Font: Arial normal, 9)
Macaé Group, this stratigraphyc level respresents an
Albian marine megassequence, composed by shallow
water carbonates mudstones and malrs.The Macaé
Group was divided into two levels (Baumgarten, 1986)
“Lower Macaé’’(Quissãma Formation),reservoir level,
defined by calcarenite and calcisilte distributed in
diferents facies, the principal reservoir is composed by
packstones oolitic facies. The ‘’Upper Macaé’’(Outeiro
Formation) is composed by calcilutite and mars and
represents the seal of the petroleum system recognized
as Lagoa Feia – Macaé.
The oil production of Bonito field comes from calcarenites
of “Macaé Inferior” (Quissamã) Formation and
sandstones of Carapebus Formation (Campos Group). In
this context, the objective of this research is to develop a
seismic attribute evaluation of the Macaé Group providing
the understanding of the structural and stratigraphyc
controls of the reservoir fácies distribution. This paper
establishes the relationship
between the psysical
properties of the rocks and the seismic response on
carbonate layers.
Fig.1 Last 6 months oil production, in barrels per
month.(fonte)
This research has a relevant importance since the current
exploratory context focus on carbonates rocks, and the
lack of work aiming the geophysical characterization of
carbonates.
Introduction
Nowadays, it is difficult to recognize the effective reservoir
distribution on carbonates rocks; in this sense, a research
oriented to seismic characterization of the main reservoir
properties is important to better understand the
geometrical distribution of the geological facies related to
oil production.
The seismic characterization, developed here, is based
on seismic and rock attributes interpretation with the aim
of link geophysical with geological facies in Bonito oil
field.
The Bonito oil field is located on the southern of Campos
Basin, it is one of the oil fields in the petroleum production
trend of Campos Basin. Along the mentioned trend the
Badejo, Pampo, Linguado, Enchova, Bicudo and Bonito
oil fields are recognized; the first four mentioned are
productors from Lagoa Feia Group (Early Barremian to
Late Aptian ages), the revervoir is constitutes by
carbonates interbedded with shale, siltite and sandstone.
The principal oil reservoir was defined as a high-energy
bivalve grainstones (Coqueiros Formation). (Guardado L.
R,Spadini A. R, Brandao J. S. L, Mello M. R,2000).
Bicudo, Linguado and Bonito oil fields are produtors at
Fig1. Mudar figura destacar o Macaé(zoom).
Fig 2. Localização
Thirteenth International Congress of the Brazilian Geophysical Society
SHORT TITLE (50 LETTERS MAXIMUM. FONT: ARIAL 9)
2
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
n
Method
Base de Dados: Será feito mais para frente.
I
amp
2
k
Log Interpretation and well correlation: this phase is
based on a lithological and stratigraphy interpretation
using wire logs as: Gama Ray, Resistivity, Sonic Profile,
Density and Neutron logs in order define the tops of the
next levels: Macaé Formation, Outeiro Formation marked
by a boot shape on Resistivity log, Quissãma Formation,
Lagoa Feira Group.
The main reservoir and its related stratigraphyc levels
(XXXX,xxxxx,zzz,cccc) were correlated between 6 wells
available for the study, as show in the figure ccc.
Seismic Interpretation:
The xxx stratigraphic levels were interpreted on the
seismic volume; the well information was calibrated on
time domain through the synthetic seismogram, and the
main reflectors were picked.
Seismic Calibration: this step was based on the
confection, of a pseudo-checkshot table, derivate
from sonic log, for the intervals without data it was
used the replacement velocity of 2300 m/s. The
pseudo checkshot table gives the deep and the
corresponding time, enabling to position the well
on seismic that also is in time.
k= number of live samples
The second attribute applied were Energy, the response
is the he amplitude of reflection strength at the point
which the energy envelope is maximum. One value is
obtained for each energy lobe is returned a as a constant
for the entire time width of energy lobe, is mathematically
represented by:
n
I
amp
2
Both of the mentioned attributes, identify isolated
amplitude response from background features, mainly
lateral variations.
Seismic to Geological Facies: for the establishment of
the relation between rock properties and the seismic
attributes cross plots were generated:
Figuras dos cross plots.
Figure 3- Time/ Depth graphic, from checkshot
table.
1.
Seismic Interpretation: The sea bottom
reflector was interpreted to get a control of the
water layer geometry. The Oligocene horizon
was interpreted because an idea about the
geometry of the reflectors, above and below
this sequence, is necessary to control the
pale-geometry of the carbonates sequences
observed along Bonito field (Siri Member,
Quissamã Fm. and the Coqueiros Member
from Lagoa Feia group.
Finally the top of Macaé Group (Outeiro
Formation) was interpreted based on wire log
interpretation as well as the main reservoir
(Quissamã Formation) top.
Examples:
Structural Maps: with the seismic interpretation
completed a structural map, in time, were generated to
top of Outeiro Formation and to Quissamã Formation.
Explicar o método de krigagem e acrescentar um map
Seismic Attributes Maps: The seismic attributes
generated to may map directly hydrocarbon indications
were RMS Amplitude, this attribute is the square root of
the sum of square amplitudes, divided by the number of
live samples(Schlumberger,2007), as shown in the
following formula:
Thirteenth International Congress of the Brazilian Geophysical Society
AUTHORS (50 LETTERS MAXIMUM. FONT: ARIAL 9)
3
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Conclusions
Results
Acknowledgments
References
Thirteenth International Congress of the Brazilian Geophysical Society
SHORT TITLE (50 LETTERS MAXIMUM. FONT: ARIAL 9)
4
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Thirteenth International Congress of the Brazilian Geophysical Society