Using Fluid Inclusions to Explore for Oil and Gas - Ronda Uruguay

Using Fluid Inclusions
to Explore for Oil and
Gas
Mr Douglas Langton
Fluid Inclusion Technologies, Inc.; USA
www.fittulsa.com

Types of Fluid Inclusions
1: Gas
2: Water
3: Liquid
Petroleum
(Plane Light)
4: Liquid
Petroleum
(UV Light)
1 2
3 4
10 microns

Inclusions Trapped During
Cementation

Inclusions Trapped During
Microfracture Sealing
Open Fracture

Inclusion Attributes
Entrapment does not require pore-occluding
cements or high burial temperature
Trapped fluid is not devolatilized, degraded
or contaminated during or after sampling and
storage
Fluid Inclusions remain in the rocks even after
pore fluid changes
They are “time capsules” representing the
fluids history of a well-section

More Inclusion Attributes
The fluid inclusion record can contain
evidence of multiple charges
Each fluid inclusion documents physical
conditions of trapping (PTX)
Fluid Inclusion abundance tends to
reflect hydrocarbon distribution and
porosity-permeability relationships in
reservoirs

A Petroleum System
Fluid inclusion techniques
can address a large number
of issues from basin to
prospect scale, revolving
around source rock, seals,
migration, paleo-columns
and present day distribution
of petroleum

FIS Schematic

FIS Data
Black = Inorganic species
Red = Gas-range HC’s
Blue = Water-soluble species
Green = liquid-range HC’s SEAL ZONE
BYPASSED PAY ZONE
THIN MIGRATION ZONES
AND SEALS
SEAL ZONE
PAY ZONE
GAS-OIL CONTACT
OIL-WATER CONTACT

Fluid Inclusion Petrography/
Microthermometry (FIPM)
Optical examination of thick polished
sections of rock material under plane
light and with UV (365 nm) excitation
Documentation of inclusion types,
distribution, abundance and relevance
Measuring phase changes during heating
and cooling (-196 to +200 o C)
Deducing Temperature, API Gravity
and Salinity

Oil/Condensate Inclusion Abundance:
Migration vs. Paleo-accumulation
None Rare Several Common Abundant Extrem. Abund
No Migration
Migration
No
Accum.
Accumulation;
Paleo-accumulation

Low fluid inclusion abundance

High fluid inclusion abundance

Hi-Res GC and GCMS of
Fluid Inclusion Extracts
Quantitative extraction and analysis of
exhaustively cleaned samples via GC
and/or GCMS
Data is used to correlate inclusion oils to
source rocks or produced oils, as well as
provide information on maturity,
compositional attributes and extent of
alteration

Stable Isotope Analysis of
Fluid Inclusion Extracts CSIA
Quantitative extraction and analysis of
samples containing anomalous
concentrations of gas-range species
GC analysis of C 1-C 5, CO 2, N 2; isotopic
analysis of d 13 C for C 1, C 2 and C 3
Data is used in correlation, seal,
compartmentalization and gas source /
maturity studies

Case Studies

Dry Hole with Up-dip
Closure
Shallow FIS microseep
suggests deeper liquid
hc charge in the area
API = 46 o
FIS data from dry hole
indicate gas and liquid
range hc’s. API gravities
match produced fluid.
BTEX anomaly suggests
nearby charge

Prospect Ranking
FIS data indicate gascondensate
migration
through Prospect #2
fault block only
FIS microseep
suggests
reservoired hc’s in
the area
API = >52 o

Proximity to Pay
FIS data
document
diffusion of BTEX
and organic acid
across lateral fault
seal at reservoir
depth. Similar
anomalies are
seen in the water
leg. Presence of
these features
significantly
enlarges
exploration target
and extends view
well beyond the
limits of the
borehole
BTEX and organic
acid anomalies in
reservoir equivalent
section across fault
Benzene
C 7
Oil indications
in reservoir
Acetic Acid
BTEX and organic acid
anomalies in water leg
to updip oil reservoir.
= diffusion of water soluble species
Benzene

Pay Delineation and
Reservoir Compartments
Decrease in C 7 and
concomitant
increase in AA
demarcates the
OWC. Detailed C 7
response in oil leg
reflects poroperm.
CO 2 shows position
of carbonate
cemented zones,
which act as intrareservoir
seals or
baffles. SrRSA and
fluid inclusion
salinity also show
major compartment
boundaries
8525
8575
8625
8675
8725
8775
8825
C 7 Acetic Acid CO 2 Sr-RSA FI Salinity
0.E+00 2.E+04 4.E+04 6.E+04 8.E+04 1.E+05
8525
8575
8625
8675
8725
8775
8825
0.E+00 5.E-02 1.E-01 2.E-01 2.E-01
Barrier
OWC
Barrier
8525
8575
8625
8675
8725
8775
8825
0.E+00 5.E+06 1.E+07 2.E+07 2.E+07 3.E+07
8525.0
8575.0
8625.0
8675.0
8725.0
8775.0
8825.0
0.7090 0.7090 0.7091 0.7091 0.7092
8525
8575
8625
8675
8725
8775
8825
9.E+04 9.E+04 1.E+05 1.E+05 1.E+05 1.E+05

FIS Microseep
Over an Oil
Reservoir
Key indicator
species form by
Bacterial Sulfate
Reduction (BSR)
in the presence
of light hydrocarbons
seeping
from depth.
About 90% of all
oil and
condensate
bearing wells
contain an FIS
microseep
FIS Microseep
60 o C
Sealing Interval
Main Reservoir Sand
CO 2 C 1 C 7 S 2+SO 2 CS 2+HC

E1-NC35A
Oil discovery in
Metlaoui
FIS microseep
Consistent with presence of
oil column in the well
Base of feature at about
3000 ft suggests fairly high
heat flow of about 45 o C/km.
In general, bases of seeps
in this study are in the
3000-5000 ft range,
suggesting gradients of 35-
45 o C/km. Consistent with
reported heat flow values.
Mio
Oligo
Eoc
Paleo
Cret
OWC
POWC

E1-NC35A
Oil discovery in
Metlaoui
Oily Tertiary
Gassy
Cretaceous
Mio
Oligo
Eoc
Paleo
Cret
OWC
POWC

E1-NC35A
Oil discovery in
Metlaoui
100 ft column of oil
currently in reservoir.
400 ft column of oil
documented in fluid
inclusion record.
Mio
Oligo
Eoc
Paleo
Cret
OWC
POWC

E1-NC35A
Oil discovery in
Metlaoui
PTPL below current oilwater
contact is sensing
overlying charge.
PTPG in Cretaceous may
indicate gas potential
(probably sour).
Mio
Oligo
Eoc
Paleo
Cret
OWC
POWC

Attahadi
(FF27-6)
Gas-Condensate in
Cambro-Ordovician
Main FIS anomalies occur in
the Eocene and Cretaceous
to Cambro-Ordovician. The
most prominent gascondensate
to oil zone at
about 6000-7500 ft contains
common oil inclusions in
some samples and suggests
a paleo-column of oil. The
tested gas zone is defined by
methane-enriched gascondensate
responses and
contains lower abundance of
liquid petroleum inclusions.
Undif
Eoc
Paleo
to Eoc
Cret
Camb/
Ord

Offshore Libya Oil Type End-Members via Steranes (m/z 218)
Abundance
Type A-1
C27 ba
Type A-2
C27 ba
Type A-3
C27 ba
Type B
C27 ba
Type C
C27 ba
C27 abb
C27 abb
Time, min
C28 abb
C28 abb
C27 abb C28 abb
C27 abb
C27 abb
C28 abb
C28 abb
C29 abb
C29 abb
C29 abb
C29 abb
C29 abb

Spider Plot – Oil Types; Offshore Libya
C29/C27 abb Sterane
C35H Index
Sterane/ Hopanes
C29/C28 abb Sterane
GAM Index
30-norH/ C30H
C23t Index
10
1
0.1
0.01
(C32H/C31H) 2
C19..C26t/ C29...C33H
C29H/ C30H
C24T/C26t
Ts/Tm
(C28t+C29t+C30t)/ C30H
C29*Ts/ C29H
C30diaH/ C30H
Primary
Oil Type
A-1
A-2
A-3
B
C

Example FIS Data, N. Sea

FIS LAS files to Seismic
GR
Benzene
Pliocene
Palaeocence
Home Sand
Brent
GR
Benzene
Upper part of
Magnus sand

Regional Studies
FIS regional studies – cost effective way
to access data
More integrated interpretation resulting
from studying multiple wells
Regional synthesis and summary maps
GCMS / GSIA module gives more
detailed information of the petroleum
system

Regional Gas vs. Liquids
FIS data define dry
gas, gas-condensate
and oil prospective
areas. Some are
consistent with
historical production.
Others suggest liquid
petroleum potential in
areas previously
thought to be gas
prone.
Gas
Liquids
Matagorda
Island
North Padre &
Mustang Isl.
High Island &
Sabine Pass
100 km
High Island
S and ES
Texas Shelf GOM
Map View
Constant Depth

Applications of FIS to source analysis
and unconventional reservoirs
Source rocks contain appreciable
trapped gas in micro-porosity
Standard gas ratios from FIS
compositional analysis can be related to
maturity
FIS data has been used successfully to
predict sweat spots in unconventional
reservoirs.

Summary and Conclusions
Fluid inclusion techniques are robust (20+
years of testing at Amoco & FIT)
Applicable to a large variety of E&P
applications through out the whole process
Inclusion petroleum is unfractionated and
unaltered (fluid time capsules) by sampling or
storage procedures.
Techniques are applicable to oil-base mud
systems.

FIS Applications
Prospectivity of petroleum system
Migration and basin modeling, charge &
timing
Petroleum type, API gravity, salinity,
temperature, can be obtained.
Present / past petroleum distribution
Source, eval. of maturity and correlation
Seals and compartmentalization –
reservoir geometry

Off-Shore Uruguay
•Analysis of residual
pore fluids
•Identify the existence
of petroleum systems
•Deepen the
understanding of the
history of migration
and charge
•Identify the number
and potential of source
intervals
Lobo
Gaviotin
•Completion November 2011

Off-Shore Uruguay
•Photostrat log for each
sample
•FIS screening analysis
of Lobo and Gaviotin
•Digital files of the
volatile geochemistry
for each well
•API gravity and
temperature data for
fluid inclusions
identified.
Lobo
Gaviotin
•Completion November 2011

Muchas gracias por
su atención