Outcrops of turbidite sandstones of the Pico Formation (upper Pliocene) at Ventura field and vicinity were examined to gain an insight into their continuity.

Two types of reservoir quality sandstones were recognized based on physical and petrophysical properties. Type A sandstones (graded, poorly sorted) have low permeabilities (several hundred millidarcys). Type B sandstones (nongraded, moderately to well sorted) have high permeabilities (several thousand millidarcys).

Three classes of turbidite packages were distinguished based on internal arrangement of sandstone types. All 3 packages contain thin-bedded Type A and B sandstones. A Class I package has, in addition, massive, composite Type A sandstones at the base; a Class II package has the massive, composite Type A sandstones in the middle; and a Class III package has no massive, composite Type A sandstones.

Thick, composite Type A sandstones have good lateral continuity because they are amalgamated. Type B sandstones have poorer lateral continuity because of lack of communication with other sandstones.

Observations on a single turbidite package over a

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lateral distance of 1,000 ft indicate that 80% of the Type A sandstone is continuous for this distance, whereas only 10% of the Type B sandstone is continuous. Factors for lateral continuity with distance multiplied by kh (millidarcy-feet) give a measure of the kh which may be expected to be in connection between wells various distances apart. At a distance of 500 ft from an injection well, only 60-80% of the total kh of the injection well may be in connection with a producing well, in the direction of depositional strike (north-south). In the depositional dip direction (east-west) this value may be 80-100%.

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