Normal text - click to edit

NMR T2 Relaxation for Fluid Saturation and Wettability Determination

G. ERSLAND

IRTG, Oct. 16th, 2012

Normal text - click to edit

Fractured Reservoirs

Normal text - click to edit

Capillary Pressure

Oil Pressure

Water Pressure

Oil Flow

Water Flow

Counter-Current Imbibition – Fractured Reservoirs

Normal text - click to edit

Wettability Determination

• Standard methods for wettability determination

– Amott Test– USBM– Contact Angle

NMR

Normal text - click to edit

5

4) Wettability

Sandgrain

water

oil

solidwater

oil

= 0

Water wet

Vannoil

solid

water

= 90o

Neutrally wet

solid

water oil

180o

180o

oil wet

Normal text - click to edit

Phase Coherency

Normal text - click to edit

CPMG Sequence

Normal text - click to edit

Fast Relaxation

Slow Relaxation

T2 is a measure of Poresize

Normal text - click to edit

Poresize Distribution -NMR

Normal text - click to edit

M0

Mxy

Time

Mxy = M0*exp(-t/T2)

Sig

nal I

nten

sity

T2 Relaxation Time

Water

Oil

NMR Homogeneous Magnetic Field

N S

B0

Normal text - click to edit

Homogeneous Chalk

Heterogeneous Limestone

T2 versus Wettability

Normal text - click to edit

Capillary Pressure

Oil Pressure

Water Pressure

Oil Flow

Water Flow

Counter-Current Imbibition – Fractured Reservoirs

Normal text - click to edit

Pore occupation – T2 mapping

M0

Time

Mxy = M0*exp(-t/T2)S

ign

al In

ten

sity

Relaxation time, T2

Water

Oil

N S

B0

Normal text - click to edit

Oleg V. Petrov , Geir Ersland , Bruce J. Balcom, Journal of Magnetic Resonance Volume 209, Issue 1 2011 39 – 46,

Normal text - click to edit

Pore Occupation – T2 mapping of counter-current water imbibition in strongly water-wet chalk

Shrink Sleeve

POM

Chalk with oil and 30 % initial water

Brine

N S

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Water Imbibition from top – strongly water wet chalk

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit

Core lengthT2 (ms)

Water

Oil

Normal text - click to edit