Mungo is a large oilfield with a small gas cap, which separates liquids from gas. It has been developed under combined water and gas injection on a Normally Unmanned Installation (NUI) located above the field and tied back to the Central Processing Facility (CPF). Processed gas and water is delivered from the CPF for injection into the Mungo reservoir. The facilities:
- The liquids flow directly to the CPF in a 12-inch pipeline.
- Chemicals and electrical power for Mungo are supplied via an umbilical from the CPF.
- A 16-inch wet gas line from the Mungo NUI is routed to the CPF via Monan.
- Minimal equipment is installed in order to achieve the normally unmanned status of this installation.
Monan a small oil and gas field with oil and gas in a turbidite reservoir in a diapir flank setting. It is produced under natural depletion with a subsea manifold and a spur line linking into the we gas pipeline between the Mungo NUI and the CPF some 15 kilometres away. A two well cluster feeds back to the CPF via the 16-inch wet gas pipeline, which also receives the 12-inch oil line direct from Mungo.
Marnock is a large gas condensate field. It is located immediately beneath the Central Processing Facility (CPF). The Marnock reservoir:
- A gas condensate accumulation.
- High pressure/high temperature (HPHT) field at initial conditions of 9000 psi and 150oC.
Machar is an oil accumulation in a fractured chalk reservoir also on a diapirflank. Producing wells are tied-in to a subsea manifold and then exported to the CPF, via a 16' pipeline. Water injection and gas lift is provided from the CPF.
Mirren and Madoes
Mirren and Madoes are accommodated within the existing CPF operational capacity. New reception, metering and subsea controls systems were added. All wells are tied-in to a subsea manifold prior to export to the CPF iva a 10-inch pipeline. Wells are controlled using electro-hydraulic control systems, consistent with the existing ETAP fields with essential chemicals fed through umbilicals.
- Situated 13km ease of the CPF.
- A normally pressures reservoir
- A Palaeocene diapir structure with a 500m-gas cap.
Future provisions exist to provide well gas lift to Mirren to assist well performance.
- Situated 19km ease of the CPF.
- A pressurised Eocene reservoir
Heron, Egret and Skua
Heron, Egret and Skua are developed jointly subsea as three separate wellhead clusters tied into two 10-inch flow lines back to the CPF. They are relatively deep (up to some 4500 meters) and classify as HP/HT - High pressure/High temperature fields.