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The Pacific Coastal and Marine Science Center's primary instrument description lists configurable acoustic sources and hydrophone acquisition, including boomer plates, sparkers and complementary chirp sub-bottom profiler equipment. It explains why the equipment configuration is chosen for target materials and imaging depth.

An underwater acoustic pressure sensor. A hydrophone streamer records fluid P waves; observing ground S waves directly instead requires coupled solid-motion sensors.

Recommend a three-dimensional multichannel seismic reflection survey, with enough areal aperture, offsets and repeated coverage to image the reservoir top, base, structure and possible leakage faults. A two-dimensional reconnaissance line can be cheaper but cannot map a three-dimensional closure reliably and is vulnerable to out-of-plane reflections. Use seismic migration to position dipping reflectors and faults; repeatable acquisition is desirable if later carbon capture and storage monitoring is intended.

A tuned marine marine air-gun array supplies broadband low-frequency seismic wave energy that can penetrate to $1.5\mathrm{km}$. Its trade-offs include bubble oscillations, seismic source ghosts, environmental constraints and limited high-frequency resolution. Sparker seismic source and boomer seismic source sources can provide higher-frequency, high-resolution shallow imaging, but commonly lack the energy and low frequencies needed to make them the first choice for this target. Source energy, bandwidth and repeatability must be balanced against penetration and vertical seismic resolution, approximately $V/(4f)$; at $V=2000\mathrm{m}{\mathrm{s}}^{-1}$ and $f=50\mathrm{Hz}$ this is about $10\mathrm{m}$. Required resolution ultimately depends on the unknown reservoir thickness.

A towed hydrophone streamer efficiently records pressure over many channels while a vessel moves. It primarily records P-wave pressure in the water, with flow noise, tow-depth ghosts, acquisition footprint and access restrictions as limitations. Seabed multicomponent nodes use hydrophones and geophones: pressure plus three-component ground motion can separate wavefields and recover converted S-wave information, and nodes permit wide azimuths and repeat surveys. Their costs include deployment, retrieval, coupling and positioning. Direct S waves do not propagate through the water column. The roughly $50\mathrm{m}$ water depth also creates a strong short-period water-layer seismic multiple that must be treated in processing.

Let a positive incident stress wavelet be $w(t)$ and measure return times relative to a receiver just above the reservoir. The top interface gives a negative P return of amplitude $-3/19$ and no basal P return. For a separately generated and measured S wave, the top return is also negative, $-3/19$, while the basal return is positive, $1/9$ at the lower interface.

If $h$ is reservoir thickness, the basal return arrives $2h/V_{P2}$ or $2h/V_{S2}$ after the top return; no numerical $h$ is supplied. Including downward and upward transmission through the top boundary, but ignoring seismic attenuation, spreading and seismic multiples, its observed S-wave amplitude isThus the synthetic S trace has an earlier negative wavelet and a later, smaller positive wavelet; the synthetic P trace has only the earlier negative wavelet. The figure chooses $h=250\mathrm{m}$ solely to separate the pulses visually. Receiver electronics or a displacement convention can reverse the displayed trace polarity, so the convention must accompany the sketch.

A marine hydrophone streamer with a purely normal-incidence P source does not directly record the hypothetical S trace. A seabed multicomponent receiver and suitable S excitation or oblique-incidence seismic mode conversion are required. This distinguishes the calculated solid-layer response from what a particular acquisition system can measure.