Seismic data that is processed, tested and verified by an independent external consultant gains a significant extra value. Obtaining processed seismic data involves the application of the correct filters to reduce random and coherent noise, picking the correct velocity values and properly editing highly complex data. Quality control checks can help prevent whole batches of data from having to be re-processed (which sadly, still happens today). Rectifying processing errors at an early stage can save the operator much time and wasted expense.
The Geo People provide the following seismic processing and interpretation services:
Our seismic processing QC will process/convert the raw seismic data from SEGD format to SEGY format, using ProMAX, GLOBE Claritas, or other seismic processing software. To maximise quality assurance, data is processed with software (and thus, algorithms) specifically chosen to be distinct from that used by the seismic acquisition contractor. The outputs from the contractor and from the QC processing flows are then monitored, compared and cross-checked, using selected parameters.
Processing & interpretation
Seismic processing is one of the biggest reasons for time delays faced by operators before making decisions on where to drill. The actual cost is dependent on the physical processing power required to compute enormous amounts of data, making the right choices for processing and effective supervision, ensuring not to have to re-process whole batches of data.
The three main seismic data processing methods may be summarised as follows:
The deconvolution and stacking processing is best conducted out in the field, as the logistics are easier and it also allows the processing flow to feed back quickly.
The migration processing normally takes place after the survey. However, if the contractor has suitable facilities and the client representative is sufficiently qualified and experienced then another, quicker form of migration processing can also take place out in the field when the survey is still ongoing, in the form of a smaller migrated 3D cube. This can save time and expense for the operator, because the rig plant can be approximately positioned, prior to the full survey result, instead of the operator having to wait for the off-site migration processing to be fully completed.
The degree of the complexity of seismic processing acquired by the operator in the field is dependent on the processing capability of the contractor, the skill levels of the contractor (and independent consultant), and the readiness of the operator to invest in this process.
Land & marine field processing QC
The Geo People land and marine seismic processing QC client representatives are experienced in using all major industry-recognised seismic processing software. They also have had experience of working with at least one seismic contractor, prior to becoming a consultant.
The processing QC usually works with the acquisition and survey QCs. They meet daily (and sometimes more frequently) with the contractor’s processing group in the field to review the processing test results and monitor production in near enough real time, reducing the likelihood of costly mistakes and re-shoots and ensuring that the appropriate tests and processes are being selected.
The seismic processing QC often controls/oversees all stages of the processing cycle: from the parameter testing at the start of a project, through to QC of the seismic data during the survey. A seismic processing QC final report is then written (and edited/technically reviewed by The Geo People) for the operator and any partners, within the specified time frame. The consultant will often supervise the project's seismic processing post-field acquisition, providing continuity of QC, consistent ownership of the QC process cycle, and the ability to address any questions processors may have about the acquisition. This makes for an efficient operation and many of our seismic processing QCs are experienced and qualified enough to perform this task.
Post-acquisition processing QC supervision
The Geo People often carry out independent QC of in-house seismic data processing which is carried out within the processing houses selected by the operator, often on a weekly or bi-weekly basis, and at significant points throughout the stages of the seismic processing sequence. The Geo People aim to provide specialist geophysicist consultants that reside in close proximity to the processing house minimising accommodation and transport costs for the operator. However, when a consultant is requested by the operator by name, then The Geo People organise transport, accommodation and visas for travel further afield say once or twice per week. When full time supervision is required, usually based on five day weeks, the consultant is provided with lodging and transport and all the support usually required for working abroad.
Seismic data processing QC is conducted at each stage of the processing. Face-to-face talks between the processing QC and the seismic processing contractor covering parameter selection, test results and proposed processing steps, ensure good communication and an efficient use of time. At the end of each day, a report is sent to the client with a summary of the day’s events, a list of significant decisions, any issues and the expected date of completion. Clients may or may not wish to be involved with the seismic processing as logistically it may be difficult to be on site. When they do, then the independent QC arranges for them to be present at critical points during the processing in addition to whatever stage of the processing is important to the client. Presentations are given by the QC to the clients and partners and/or contractors to clarify, summarise and streamline events.
For large surveys, the processing of the seismic data in-house often starts before the acquisition has finished saving the operator time. In these circumstances, the independent in-house seismic processing QC has the opportunity to communicate with the seismic processors and observers in the field and sends feedback as well as communicates on issues such as positioning, reporting, acquisition parameters etc. It can be a challenge to interpret crew reports post acquisition and/or if the in-house processors do not have any field experience. The presence of an intermediary, the independent in-house seismic processing QC with field experience, ensures that the communications with the contractor are efficient and precious time is not lost.
Specialist processing projects
Our seismic data processors for specialised projects have specific expertise for particular processing challenges. SEGY datasets are scanned for completeness before delivery to seismic processing houses whereby the seismic numbering, navigation numbering, shot location and receiver spread is checked. For land data, once the geometry from the SPS files is applied to the seismic data, it is then checked for correctness by looking at the LMO plots and zero-offsets. Likewise, The Geo People provides a specialist seismic processing treatment service for marine seismic data, checking for incorrect headers, shot-points, data completeness, providing a completely documented dataset ready for processing.
Stratigraphic & quantitative interpretation
The Geo People has a pool of consultants available, experienced in stratigraphic and quantitative seismic and well interpretation. Stratigraphical and biostratigraphical experience in the petroleum sector includes: single well analyses, multi-well/field studies, basin studies and reporting on integrated prospectivity, stratigraphical data review and integrated basin modelling, basin-wide biozonal schemes, depositional models, biofacies, sequence stratigraphy, routine and wellsite palynostratigraphy and palynofacies from the Lower Palaeozoic to the Pleistocene periods.
The Geo People consultants are experienced in the following areas of qualitative interpretation:
Our consultants who carry out interpretation services, typically use Petrel, Geographix and Kingdom suite software. In addition to our own consultants, we have very close links with a large interpretation centre with tape storage facilities to provide for your needs.