{
  "abstract": "In multichannel analysis of surface waves (MASW), the suitability of an active source is evaluated by its ability to generate coherent and continuous surface-wave dispersion over a usable frequency and wavelength range, as these characteristics influence the reliability of mode identification and the attainable depth of investigation. We present a hierarchical paired comparison of hammer and gun acquisition protocols using 13 matched source positions and identical 12-receiver geometry (5m spacing, 55m aperture and 30m nearest offset). All 26 SEG-2 gathers were processed individually using the same phase-shift imaging and automated ridge-extraction criteria, followed by independent manual fundamental-mode picking to verify the automatic interpretation before acceptance and inversion. The verified individual gathers were then combined through normalized common-offset trace stacking and normalized dispersion-image stacking for each source. Every gather yielded an accepted fundamental-mode path. At the individual-gather level, mean maximum usable wavelength was 30.14m for the hammer and 29.45m for the gun (gun minus hammer = −0.69m; 95% paired bootstrap interval −3.81 to 1.50m). The hammer contained a greater proportional 4.5–10Hz spectral fraction (0.967% versus 0.672%), but this exploratory contrast did not remain significant after Holm correction [14]. Source-composite curves spanned 21.0–46.0Hz for the hammer and 20.5–43.5Hz for the gun, with maximum wavelengths of 32.14 and 33.41m, respectively. The stacked gun-minus-hammer wavelength difference was 1.27m (paired spatial-bootstrap 95% interval −1.39 to 2.50m), equivalent to upper screening depths of 16.07 and 16.71m under a 0.5 wavelength convention. Fixed-layer conditional inversions produced overlapping shear-wave velocity intervals in all four model layers; gun-minus-hammer differences ranged from −17.6 to +14.1m/s and all 95% intervals included zero. Agreement between independently extracted trace-stack and image-stack curves was 7.16m/s for the hammer and 4.15m/s for the gun. These results show that source ranking is endpoint- and threshold-dependent: the hammer supplied more relative low-frequency energy, whereas the gun stack gave a slightly longer wavelength, but neither a reliable depth advantage nor a distinct velocity structure was resolved. The proposed individual-to-stack consistency framework, strengthened by manual verification of automated modal picks, provides a reproducible way to prevent source-energy observations from becoming unsupported claims of deeper MASW investigation",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "name": "Prince Larbi Akor"
    },
    {
      "name": "Nelson Foli"
    },
    {
      "name": "Ruth Araba Tawiah Annan"
    },
    {
      "name": "Emmanuel Teye Mensah"
    },
    {
      "name": "Edmund Okoe Amartey"
    },
    {
      "name": "Voitey Aku Essinam"
    },
    {
      "name": "Naomi Tawiah Quashie"
    },
    {
      "name": "Judith Tansi Addy"
    },
    {
      "name": "Jeffery Nelson"
    },
    {
      "name": "Emmanuel Kwame Nuamah"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/avgxd6kj6xezt.bib",
  "cited_by": 0,
  "doi": "10.31223/x5rj8s",
  "fulltext_url": null,
  "id": "avgxd6kj6xezt",
  "issns": [],
  "landing_url": "https://eartharxiv.org/repository/view/16002/",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/legalcode",
  "metadata_licence": null,
  "native_subjects": [
    [
      "bepress",
      "Active MASW"
    ],
    [
      "bepress",
      "Depth of investigation"
    ],
    [
      "bepress",
      "Dispersion imaging"
    ],
    [
      "bepress",
      "Other Engineering"
    ],
    [
      "bepress",
      "Shear-wave velocity"
    ],
    [
      "bepress",
      "Source comparison"
    ],
    [
      "bepress",
      "stacking"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://eartharxiv.org/repository/object/16002/download/27695/",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-07",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/avgxd6kj6xezt.ris",
  "sources": [
    {
      "first_seen": "2026-11-08T12:20:49Z",
      "native_id": "16002",
      "source": "eartharxiv",
      "url": "https://eartharxiv.org/repository/view/16002/"
    }
  ],
  "subjects": [
    {
      "field": "earth",
      "origin": "source:eartharxiv",
      "subfield": "general"
    }
  ],
  "title": "From Individual Gathers to Source-Composite Inversion in Active MASW: A paired field comparison of 8kg hammer and gun acquisition protocols",
  "title_text": "From Individual Gathers to Source-Composite Inversion in Active MASW: A paired field comparison of 8kg hammer and gun acquisition protocols",
  "type": "preprint",
  "updated_at": "2026-11-09T12:20:28Z",
  "url": "https://research.draconitic.com/paper/avgxd6kj6xezt",
  "venue": "EarthArXiv",
  "versions": []
}