First Break - Volume 42, Issue 11, 2024

This paper sets out to provide a suggested standardised set of nomenclature for seismic interpretation data of different frequency (Hz) spectra in use in the offshore energy sector. Historically, a large number of acronyms have been used to describe seismic interpretation data of different frequency content across the oil and gas industry and now in the rapidly growing offshore wind and carbon storage sectors, but the terms in use have not always been consistent or logical.

This paper sets out to understand the history and background behind the evolution of these terms and to remove the confusion from current usage of MR, HR, UHR, UUHR, VHR, or SUHR by definition of a standardised nomenclature for seismic interpretation data ranging from 4Hz up to 5000Hz in frequency content. It is believed application of such a standard throughout the global offshore energy industry will ensure consistency and a common understanding going forward.

We present a shallow-water case study offshore Malaysia where a Tuned Pulse Source (TPS) and Conventional AirGuns (CAG) were deployed simultaneously, in a Dispersed Source Array (DSA) mode, to acquire seismic data with Ocean Bottom Node (OBN) and borehole distributed acoustic sensor (DAS) receivers. Both TPS and CAG were deployed from a single source vessel, using a single compressor package in a single pass. This industry-first novel deployment was also the first time the TPS source and MEMS-based OBN had been deployed in tandem to ensure optimum low-frequency signal from the emission stage to 4C fidelity sensor recording.

The Society of Petroleum Engineers (SPE) has proposed a framework for the classification of CO2 storage resources and storage capacity, known as the Storage Resources Management System (SRMS, 2017). The SRMS framework aims to provide guidelines for the classification and reporting of CO2 assets. It’s similar to SPE’s well-established framework for hydrocarbon resources and reserves classification, known as the Petroleum Resource Management System (PRMS, 2018). Meanwhile, revisions of both the 2018 version of PRMS and 2017 version of SRMS are underway, with public consultations of practitioners completed in 2024 (PRMS, 2024; SRMS, 2024).

While the PRMS is actually used industry-wide, this cannot be said for the SRMS. There is a nascent CO2 storage business segment, with mushrooming carbon removal startups. This fledgling new industry is now proposing a carbon removal quality assurance Code of Practice, at the same time as SPE is spending efforts on revising its carbon resources management system. The absence of track record and weak incentives, as well as a lack of case studies on how to apply SRMS in practice, are lurking in the background. Additionally, the groundswell of arguably opportunistic providers of storage capacity has created an unprecedented situation where carbon removal companies offer mostly unclassified storage capacity (in SRMS classification’s sense), as will be detailed below. The lack of validated storage capacity is an important hurdle in startup credibility — investors should be wary.