Previous Lecture Complete and continue  

  1. Introduction

- [Instructor] Hi everybody, thank you for giving me this opportunity to talk today. I will be talking about applying a consistent evaluation approach to thin bedded sands in the Gulf of Mexico Deepwater Field. So, the outline goes as follows. I would first talk about the objective, and give an introduction to the issue. Then, I would show some core photographs of how the thin and massive beds in the reservoir look like. I will then talk about rock properties. I'll start with porosity of the reservoir, how I have attempted to tie it to core, and then we would move to net-to-gross. I would again show how the net-to-gross has been calculated and how it has been tied to core net-to-gross, and also to net-to-gross derived from nuclear-magmetic-resonance logs. I will then move to saturation. So, we would talk about sand fraction saturation, and how that has been tied to core measurements, which is Dean-Stark measurements for saturation. Also, catalytic designs, porous plate measurements. In the end, I would be comparing the results against conventional workflow. The objective of this study was to actually evaluate thin-bedded sands using a Thomas- Stieber approach. In this study, the field has been located in the Gulf of Mexico Deepwater, and throughout the presentation, I'll show how, through Petrophysics, we can apply a consistent and a cross-verified approach to evaluate thin laminated sands, which are beyond the resolution of logs. The problem that we were facing was that the wells in the field of study continue to overperform expectations. Approximately 15 to 20% of the volumes is in the thin beds. To get a realistic net pay, we had to approach it in a different fashion. We had to do a more holistic, take a more holistic approach where we integrate core and log, and also use a different method of interpretation. Thomas-Stieber is not a new approach. It has been used historically in conventional clean, thin-bedded sands, and I will show here how the Thomas-Stieber approach has been used for calculating the properties of the sand fractions in those thinly-bedded sands. I'll also show how this approach has been integrated with advance log, like animal, and also how the core has been used to obtain additional information, which has confirmed our observations.