This is an usual task I've done last 15 years, not only in my leads from Reconcavo, Camamu and Campos Basin but also evaluating other areas offshore Brazil and International. Pre-mapped Petrobras prospects from Exploratory Blocks in many basins, from Brazil and International areas, were usually sent to me do to the prospect evaluation. Only in an offshore area in Brazil N-NE I've mapped and evaluated approximately 140 leads from four 3D surveys. In this evaluation it was used many tools including Wavo, Shaleind, shift-drift methodology, etc. Many evaluated prospects with WAVO positive DHI from many basins were drilled successfully. The last 5 oil/gas accumulations found in Sergipe-Alagoas Basin were supported by Wavo. In same basin, one lead pointed by WAVO as low atractivity (no positive DHI) resulted dry. The lead was drilled because there was positive DHI from other AVO tool. The summed efforts of Wavo and Shaleind pointed some partnership prospects as dry or reservoir absent. After drilling, this was the proven result. In WAVO special page one find more about these techniques.
When doing a prospect evaluation, it is my procedure to use any geophysical/geological information in the area. Using this database, it is usual to do seismic velocity evaluation, well to seismic correlation, AVO studies, netpay computations, net to gross computations, impeadance studies, etc.
Well Post Mortem
I've done many well Post Mortem, sometimes as a revision. The last revision I've done was a dry well from an Africa Basin supported by AVO DHI. The official report to date was a failure due to layer anisotropy. To do this I received 3D Far and Near data. In the generated report my conclusion is "use of inappropriate offset data". The far data used were reflections including data after critical angle. It was possible to recognize "head waves" in the gathers used to constitute the far offset data volume.
Exploratory Block Evaluation
It was a daily task to do exploratory block evaluation. Since 1995, I'm involved in this type of job, here including ring fence areas. In 1998 I became TCR of BREC1 (Reconcavo Basin) and BCAM1 (Camamu Basin) farmout blocks. The exploratory evaluation of ring fence areas is similar to evaluate exploratory blocks. Sometimes it is not an easy task, because the "big fishes" were drilled. From the other hand, in ring fences you have more geological and geophysical information available. I've done this type of work in Cuenca Austral (Argentina), Brazil onshore and offshore Basins, Angola, Namíbia and Tanzânia. My reports in Angola, Namíbia and Cuenca Austral were 100% assertive. In Tanzânia I have not done prospect evaluation to be drilled, only reviewed some leads and have done a Post Mortem.
Consultant in Seismic Acquisition and Processing
I'm not able to discuss the up to date technology in seismic acquisition. I may discuss Field quality control and Survey Design. The first Petrobras 3D Survey Design tool (P350) was a special project I've done at time of my Master Thesis. Recently I ask "Why are we acquiring 8000m offset data in seismic surveys? It does not make sense, because 40-50% of far data will be muted in seismic processing". When we went to processed data, we realize the data were muted close to 4.300m. Near 50% of survey effort is now on the trash.
About seismic processing, although I left Seismic Processing as Technical Manager and Technician since 1995 I've been following the evolution in this area. The main new techniques are developed to follow the massive amount of recorded data and to best image the geological data. Here we may include the new techniques in PSTM and PSDM. The old techniques to evaluate/enhance data are still online.
Seismic to well correlation
Are You in doubt about a seismic to well correlation? This is one task I'm very skilled. Many times doing this task things changed: the interpreted seismic layer was not the one inittialy assumed from the well geological information. See page Time x Depth, where this matter is more detail discussed.
Seismic velocity is a very important atribute. In page Velocities You will find more information about seismic velocities. From my experience, I may say that velocity interpretation is not an easy task. Only in case of high quality seismic data interpreter can navigate with some comfort. One paper about seismic velocities is disponible in Velocities page.
Exploration to Production transition
Since year 2000 I was working in Campos Basin Petrobras Regional Unit (UO-BC). The Exploration and Production activities are very close, many times overlapping. Some oil discoveries from my leads became oil producers. Petrobras offshore time record transition from exploratory well to production well is BG-16 wildcat, one of my leads. 29 days after finishing exploratory well it became a producer well to Cherne1 Fix Platform. Another example is Simental lead, in Marimba Ring Fence, a wildcat well that became producer one year after. The Rio de Janeiro FPSO project was launched after my report on RJS409 area and after drilling ESP18DP, ESP19 and ESP20. In this report the VOIP indicated is 150% higher then the VOIP assumed to report date. I have participated in the Rio de Janeiro FPSO production project. Other wildcats became producers and some are waiting for production facilities. In May/2013 there was 5 prospects from my leads waiting to be drilled.