{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T03:34:45Z","timestamp":1768707285197,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,28]],"date-time":"2022-12-28T00:00:00Z","timestamp":1672185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014772","name":"Colorado Department of Transportation","doi-asserted-by":"publisher","award":["20-HAA-ZH-03024"],"award-info":[{"award-number":["20-HAA-ZH-03024"]}],"id":[{"id":"10.13039\/100014772","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Rockfall processes are now commonly studied through monitoring campaigns using repeat lidar scanning. Accordingly, several recent studies have evaluated how the temporal resolution of data collection and various data-processing decisions can influence the apparent rockfall volumes estimated using typical rockfall database creation workflows. However, there is a lack of studies that consider how data quality and associated data-processing decisions influence rockfall volume estimation. In this work, we perform a series of tests based on an existing reference rockfall database from the Front Range of Colorado, USA, to isolate the influences of data resolution (point spacing), individual point precision, and the filter threshold applied to change results, on the volume estimates obtained for rockfalls. While the effects of individual point precision were found to be limited for typical levels of gaussian noise (standard deviation per coordinate direction \u2264 0.02 m), data resolution and change filter threshold were found to have systematic impacts on volume estimates, with the volume estimates for the smallest rockfalls decreasing substantially with increases in point spacing and change filter threshold. Because these factors disproportionately impact volume estimates for smaller rockfalls, when these factors change, the slope of the apparent power law that describes the relative frequency-volume distribution of rockfalls changes. Evidence is presented that suggests that this phenomenon can explain discrepancies between power law slopes presented in the literature based on studies focused on different scales of rockfall activity. Overall, this study demonstrates the impacts of raw data attributes on rockfall volume estimation and presents an additional effect that tends to bias rockfall frequency\u2013magnitude power law relationships towards underestimation of the relative prevalence of small rockfalls.<\/jats:p>","DOI":"10.3390\/rs15010165","type":"journal-article","created":{"date-parts":[[2022,12,28]],"date-time":"2022-12-28T05:30:27Z","timestamp":1672205427000},"page":"165","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Accuracy of Rockfall Volume Reconstruction from Point Cloud Data\u2014Evaluating the Influences of Data Quality and Filtering"],"prefix":"10.3390","volume":"15","author":[{"given":"Gabriel","family":"Walton","sequence":"first","affiliation":[{"name":"Department of Geology and Geological Engineering, Colorado School of Mines, Golden, CO 80401, USA"}]},{"given":"Luke","family":"Weidner","sequence":"additional","affiliation":[{"name":"Department of Geology and Geological Engineering, Colorado School of Mines, Golden, CO 80401, USA"},{"name":"BGC Engineering, Golden, CO 80401, USA"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107069","DOI":"10.1016\/j.geomorph.2020.107069","article-title":"Quantifying 40 years of rockfall activity in Yosemite Valley with historical Structure-from-Motion photogrammetry and terrestrial laser scanning","volume":"356","author":"Guerin","year":"2020","journal-title":"Geomorphology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1016\/j.ijrmms.2006.07.014","article-title":"Forecasting potential rock slope failure in open pit mines using the inverse-velocity method","volume":"44","author":"Rose","year":"2006","journal-title":"Int. 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