Seismic Data Transcription from Vintage Magnetic Tapes to Cloud-Ready Storage

Overview

This project involved the transcription of over 5 petabytes of seismic data held on legacy magnetic tapes, migrating it to modern storage in preparation for cloud ingestion. The data spanned aging physical media in varying states of condition, requiring careful handling before any digital transfer could begin. The objective was to recover as much usable data as possible, validate its integrity at every stage, and deliver a clean, well-structured dataset ready for long-term digital use and cloud-based workflows.

The Challenge

Legacy seismic data stored on magnetic tapes presents a distinct set of risks. Physical media degrades over time, and without proper conditioning, data loss is irreversible. The project required not only recovering data from tapes of varying age and condition, but ensuring that every file transferred was an exact, verifiable copy of the original. An additional layer of complexity came from the need to generate Near Trace Gathers (NTG) and QC plots in real time during the read process, allowing data quality to be assessed as transcription progressed. Many of the tapes also held data in non-standard formats, making automated processing difficult without custom intervention.

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Our Approach

Samit developed a tailored workflow for each batch of media, with conditioning protocols determined on a case-by-case basis depending on the physical state of the tapes. To guarantee data integrity, a 256-bit hash value was generated for every file at the point of reading, with automatic validation carried out during readback — providing a mathematically verifiable proof that each copy was bit-for-bit identical to the source.

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Custom software modifications were applied to identify data formats automatically, select near trace numbers, and generate NTG and QC plots during the tape-reading process itself. This removed the need for a separate quality review stage and allowed the team to flag issues and make decisions in real time. All recovered data was catalogued into a structured database with multi-key search functionality, designed specifically to support downstream identification, sorting, and cloud ingestion workflows.

Results

• 95% media recovery rate — data was successfully retrieved from 95% of all input tapes, including many in degraded condition
• Verified data integrity — 256-bit hash validation provided client confidence that every file transferred was a perfect copy of the original
• Real-time quality assurance — NTG and QC plots generated during transcription gave the client immediate visibility into data quality, enabling appropriate next steps without delay
• Format standardisation — non-standard data formats were identified and converted, making previously inaccessible data usable within standard processing environments
• ‍Cloud-ready archive — the project delivered a clean, accurately catalogued database with multi-key search capability, fully prepared for cloud ingestion and long-term digital management