LiDAR-derived surface roughness signatures of basaltic lava types at the Muliwai a Pele Lava Channel, Mauna Ulu, Hawai‘i

We used light detection and ranging (LiDAR) data to calculate roughness patterns (homogeneity, mean-roughness, and entropy) for five lava types at two different resolutions (1.5 and 0.1 m/pixel). We found that end-member types (ʻaʻā and pāhoehoe) are separable (with 95% confidence) at both scales, i...

Full description

Saved in:
Bibliographic Details
Published in:Bulletin of volcanology 2017-11, Vol.79 (11), p.1-13, Article 75
Main Authors: Whelley, Patrick L., Garry, W. Brent, Hamilton, Christopher W., Bleacher, Jacob E.
Format: Article
Language:English
Subjects:
Basalt
Data
Detection
Earth and Environmental Science
Earth Sciences
Entropy
Flow rates
Geology
Geophysics/Geodesy
High flow
Homogeneity
Lava
Lava flows
Lidar
Low flow
Mineralogy
Regions
Research Article
Ropes
Sedimentology
Surface roughness
Volcanology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We used light detection and ranging (LiDAR) data to calculate roughness patterns (homogeneity, mean-roughness, and entropy) for five lava types at two different resolutions (1.5 and 0.1 m/pixel). We found that end-member types (ʻaʻā and pāhoehoe) are separable (with 95% confidence) at both scales, indicating that roughness patterns are well suited for analyzing types of lava. Intermediate lavas were also explored, and we found that slabby-pāhoehoe is separable from the other end-members using 1.5 m/pixel data, but not in the 0.1 m/pixel analysis. This suggests that the conversion from pāhoehoe to slabby-pāhoehoe is a meter-scale process, and the finer roughness characteristics of pāhoehoe, such as ropes and toes, are not significantly affected. Furthermore, we introduce the ratio ENT HOM (derived from lava roughness) as a proxy for assessing local lava flow rate from topographic data. High entropy and low homogeneity regions correlate with high flow rate while low entropy and high homogeneity regions correlate with low flow rate. We suggest that this relationship is not directional, rather it is apparent through roughness differences of the associated lava type emplaced at the high and low rates, respectively.
ISSN:0258-8900
1432-0819
DOI:10.1007/s00445-017-1161-5