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CSP Seismic Data Processing Method for Fracture Oil and Gas Reservoir Prospecting

TINP Ltd.

Efficiency increasing of geological surveys.

Search for non conventional deep laying hydrocarbon deposits. 1

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Supercomputer technologies for Fuel and Energy Complex

Purpose: involvement into exploration of complex and deep laying (3-7 km) deposits with fracture

cavernous type of reservoirs.

Core samples.Dolarenite. Caverns expand along fracs.

см

см

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Fracture and/or cavernous hydrocarbon reservoirs:

25-50% of world hydrocarbon resources

Don’t reflect but scattered seismic energy

Amplitudes of scattered waves are several orders less intensive then reflected ones

All these extremely complicate this reservoir prospecting

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«Second wind» of Fuel complex in Western Siberia

Thesis 1:

Non conventional deep laying fields with

cavernous type of reservoirs may contain

more than 25% of all unexplored world oil

recourses.

Thesis 3:

Production self-cost of 1 ton of a deep

laying oil in existing field, including costs of

complex exploration technologies, is 7

times cheaper than in new fields.

Thesis 2:

Ugra infrastructure includes 20 000 km of

roads, 100 000 oil wells, 66 000 of oil and

gas pipelines.

Search for conventional hydrocarbon deposits in territories of new geological exploration

Search for non conventional hydrocarbon deposits in lower horizons of existing fields

Why work with “old” fields

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Convectional technology of 2D data migration Ust-Balyk field. Bazhenov formation.

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Sedimentary cover

Basement

Bazhenov fromation

Data volume of already existing CDP results for Western Siberia: 2D- 1500 thousand km. 3D - 70 thousand square km.

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Geological objects manifested in scattered waves:

Fractured reservoirs in Bazhenov and Abalak formation of

Western Siberia

Fractured and cavernous reservoirs in Pre-Jurasic rock

complex in Western Siberia

Cambrian and Vend-Rifey deposits in Eastern Siberia

Devonian and Carbon carbonate deposits in Volga-Urals

hydrocarbon province

Paleozoic clay and carbonate deposits in Timano-Pechora oil

and gas province

Carbonate complex in pre-Caspian oil/gas province

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Theoretical background. Seismic waves propagation, reflection and scattering

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HRF ~

10~

Day surface

~ 300 30 , 3000FR m if m H m

6 3~10V m

1

3~ ~ 100d V m

10010 difr

refl

A

A(О.Kuznetsov et al., 2004)

?V

diffractor

Reflectors Diffractors

CSP METHOD

Scatter scheme Inverse scattering

problem

22 2

02

0

0

1

0

( , , ) , ?

t

uc a r u t r r

t

u

u t given a r

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Inverse scattering problem solution

0 0 0( , , ) ( , , ) ( , , )

ˆ ˆ( , ) ; ( , )

ˆ ˆ( , ) ; ( , )

( , ) ( , ) ( , )

ˆ ˆ, - linear ope

refl diffr

diffr diffr diffr diffr

refl refl refl refl

refl diffr

refl diffr

u t u t u t

u t L u a t M u

u t L u a t M u

a t a t a t

L L

rators for reflected/diffracted

waves separation

ˆ prestack migration operatorM

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Common Scattering Point technology

Reflectors Difractors

2D/3D

multichannel

seismic data Reflectors cube

Difractors cube

10010 difr

refl

A

A

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Common Scattering Point method (CSP)

22 2

02

0

0

1

( , , ) , ?

t

uc a r u t r r

t

u

u t дано a r

Wave migration

CSP is based upon: Russian mathematic school achievements in inverse problems of geophysics (academicians A.S. Alekseev, М.М.Lavrentiev, S.V. Goldin) application of supercomputer technologies of overteraflop capacity

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Supercomputer technologies

Computing capacity:12 TFlops, RAM- 4 TB

CSP difractors cut

CSP-reflectors cut

Full wave field

99%

1%

2D processing results by CSP method. Ust-Balyk field. Bazhenov formation.

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Sedimentary cover

Bazhenov formation

Basement

Oil

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2D model of balk with circle inclusion inside Vmedia=2km/s; Vbalk=2.020 km/s; Vcirc=2.010 km/s, Dcirc=20m

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CSP traces gather left – no noise, right – with noise

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Reconstruction result left – reflectors, right - diffractors

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The CSP method resolution in the anticline flexure model

smV /20001

smV /20403

smV /20202

smVe /20151 smVe /20162 smVe /20173 smVe /20184 smVe /20195

Anticline

flexure model

Conventional

proceassing

CSP processing

2D West Siberia model circle inclusion 20 m diameter

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Enlarged picture of diffractors

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Muted CSP trace gather with 30% noise

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Reflectors time section

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Diffractors time section (noise 30%)

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Diagram of seismic data processing:

Left – conventional processing Right – CSP processing of separated reflected and scattered waves

Conventional prestack

migration methods

CSP-prestack

migration method

2D/3D seismic data

Time

section/cube of

CSP-diffractors

2D/3D seismic data

Time

section/cube of

CSP-reflectors

Conventional time

section/cube

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Processing and interpretation CSP-reflectors/diffractors workflow

2D/3D seismic

data

CSP-reflectors cube

Geological data

CSP-diffractors cube

Instantaneous

amplitude

Instantaneous

frequencies

Impedance

Coherency

Instantaneous

amplitude

Instantaneous

frequencies

Impedance

Coherency

Pore reservoir model Pore cavernous

fracture reservoir

model

Cavernous fractured

reservoir model

CS

P-re

flec

tors

attrib

ute

CS

P-d

iffrac

tors

attrib

ute

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Reefs Exploration

(Devonian reefs, Volga-Urals province)

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Seismic lines

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Line 151301, Reflectors time section

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Line 151301, Diffractors time section

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Reservoir 3D model, Devonian rocks

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Diffractors map

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Forecast of fractured and cavernous reservoirs in magmatic rocks

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Seismic lines

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Line #14, Reflectors time section

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Line #14, Diffractors time section

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Line #14, combined diffractors and reflectors time section

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Reservoir 3D model (Green – horizon A)

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Isochrones (left) and diffractors (right) horizon A maps

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Forecast of fracture and cavernous reservoirs in Bazhenov and Abalak

formations (upper Jurassic)

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Line #60, Reflectors time section

Б Б1

А

Т

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Line #60, Diffractors time section

Б Б1

А

Т

Image of the method resolution ability in depth. Antarctic continental slope. Conventional time section in true amplitudes.

water

bottom

Crystal basement

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Image of the method resolution ability in depth. Antarctic. Diffractor time section based on CSP technology.

water

bottom

Crystal basement

Mantle

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3D seismic. 3D-CSP method software performance

Dell PowerEdqe M600

128 units of: Processor Quad Core Xeon E5450 -2; RAM memory 32 GB; 2 Gigabit Ethernet; 1 Infiniband. Total perfoprmance – 12 Тflops Total RAM memory – 4 Тb

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Ляминский

Сергинский

Рогожниковский

Талинский

Лебяжий Средне-Назымский

Галяновский

Ай-Пимский

Правдинский

Салымский Ханты-Мансийский

Приобский

Верхне-Салымский

Юганский

Oilfield in West Siberia with Common Scattering Point data processing

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3D-CSP processing and interpretation example. Observing scheme of the works area. Nazym.

Exploration

object

Forecast of fractured-cavernous reservoirs in Upper Jurassic and pre-

Jurassic rocks of Nazym oil field

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Exploration wells position

well №219

well №210

well №220

well №218

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Stratigraphic reference of drilling data to seismic reflecting horizons

Composite profile over exploration wells 219, 210, 220,218 with built-in logs diagram.

B horizon A horizon

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Isochrones map on reflecting horizon B (Top of Bazhenov formation)

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3D-CSP processing results. CSP-reflectors and CSP-diffractors video-cubes

Video layer

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CSP-diffractor cube combined with CSP-reflector cube

А

Б

Diffractor

Diffractor

А

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CSP-diffractor amplitudes map in interval of upper Jurassic producing horizon.

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Well 218

CSP- diffractor section

CSP-reflector section

Well 210

CSP-reflector section

CSP-diffractor section

Comparison of CSP-diffractor and CSP-reflector sections

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Instantaneous frequency map

Coherence map Instantaneous frequency map

Impedance map

Attributive analysis in B horizon of CSP-diffractor

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Productivity forecast map for Bazhenov formation according to 2D seismic (Severomorneftegeofizika, Centr 2004)

CSP-diffractor map according to 2D (left, URIIT-2008)) and 3D(right, URIIT-2013) seismic for upper Jurassic productive horizon

Comparison of the productivity maps on 2D and 3D seismic

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3000з 3002з

3001з

4001з

New wells drilled by the results of CSP technology prediction

Diffractors map

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Forecast of fractured-cavernous reservoirs in Devonian

carbonate. Gorelaya oilfield.

Exploration

object

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Diffractors map of producing interval

Oil wells

Dry wells

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Dry well

CSP-reflectors (left) and CSP-diffractors (right) time section through wells

#7,5101,51,45 and 5

Oil wells Dry well

Oil wells

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Comparison of conventional and CSP technology reservoirs

prediction efficiency

Prediction map, based on CSP technology

Prediction map, based on standard technology

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3D-CSP processing results. CSP-reflectors and CSP-diffractors video-cubes

Video layer

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Fracture-cavernous reservoirs in pre-

Jurassic rocks of Urmano-Archinskoe

oilfield

Tectonic model

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Diffractors map in producing horizon interval

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Correlation between oil flow rate and diffractors amplitudes

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correlation coefficient - 85%

Oil flow rate

Diffr

acto

rs a

mplit

udes

Map of prediction oil flow rate from fracture-cavernous intervals

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SALYM OILFIELD WEST SIBERIA

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