10.5.2 Sample Integrity and Preparation

The initial description of a fluid sample is handled as a distinct test type. The data captured includes opening pressures, volumes and phases present, gas-oil ratios (GORs), densities and/or specific gravities. Contaminants or other adverse characteristics may be identified within the fluid sample, and the laboratory may conduct and record additional steps to make the fluid sample more representative of the in-situ reservoir fluid or stock tank oil. The purposes of these analyses are to establish sample validity and repeatability to ensure confidence in results of PVT testing analyses yet to be performed. Extended validation tests, such as saturation (bubble point) pressure, viscosity measurements, air content, water content, etc., are not described in this test but may be reported in other tests.

An important step in the preparation of some separator samples is the recombination of distinct oil and gas samples into a reservoir fluid sample. This involves the physical manipulation of separator oil and gas samples to duplicate the reservoir and producing conditions observed in the field. The sample produced by this test can then be subjected to a variety of PVT and flow assurance testing to describe the reservoir from which the samples were collected.