EOR MONITORING EFFECTIVITY USING TIME LAPSE MICROGRAVITY

PROCEEDINGS JOINT CONVENTION BALI 2007
The 32^nd HAGI, The 36^th IAGI, and The 29^th IATMI Annual Conference and Exhibition

EOR MONITORING EFFECTIVITY USING TIME LAPSE MICROGRAVITY
Muh Sarkowi^1
1Geological Survey Centre, Jl. Diponegoro 57 Bandung, Indonesia

Geophysics study program Physics Department Lampung University, sarkov323@yahoo.com
Jl. Prof. Sumantri Brodjonegoro no. 1 Bandar Lampung

ABSTRACT

The time lapse microgravity is a development of the 3D gravity method which is conducted by repeated measurements of gravity with a certain time interval. The time lapse microgravity method are success to monitored groundwater level change, volcanic activity, subsidence, gas or oil production and steam production in geothermal.

In this research, the time lapse microgravity was employed in order to monitor oil production and water injection. The objectives are to understand responses and characteristics of time lapse microgravity relating with oil production and water injection. The research was started from mathematical modelling and simulations of synthetic data to understand responses of the time lapse microgravity caused by oil injection and water injection.

The response of time lapse microgravity caused oil production and water injection in reservoir are relatively small in number. The respon of time lapse microgravity for 6.000.000 barrel fluid production, density contrast 0.2 gr/cc, depth 1000 m is 20 ìgal, and 40 ìgal for depth 500 m. The positive anomaly value is caused by fluid injection, while the negative anomaly value is fluid production.

Since the microgravity changes caused by oil production and water injection in the reservoir are relatively small in number (< 50 Gal), therefore sy nthetic data modelling, special equipments, planning and strategy surveys are required to overcome problems.

Keywords : time lapse microgravity, effectivity, monitoring