Geodiversity and Its Implication for Geoconservation of the Youngest Eruptive Sites of Western Samoa

Proceedings

article

Károly Németh¹ 

[1] School of Agriculture and Environment, Massey University;Lithosphere Physics Research Group, Institute of Earth Physics and Space Science;The Geoconservation Trust Aotearoa Pacific;Saudi Geological Survey;Istituto Nazionale di Geofisica e Vulcanologia

关键词: scoria cone;    geodiversity;    geoconservation;    volcanic hazard;    resilience;    geopark;   

DOI  :  10.3390/IECG2022-13751

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

The last volcanic eruption in Western Samoa, which occurred between 1905 and 1911, produced a complex scoria and lava spatter cone and an extensive lava field that destroyed Sale’aula village, near the Pacific coast. This eruption, referred to as the Matavanu eruption, also produced pahoehoe-type lava flows with superbly preserved surface textures, tumuli, and some littoral explosion craters in its distal lava field. The unique nature of the location meant that it was selected as one of the first of the 100 IUGS Geological Heritage Sites, in October 2022. The region has been under an investigation that aims to document the geoheritage elements of the location, estimate its geodiversity, and explore the potential to develop a geopark together with local communities. All this work intends to provide a firm knowledge base to identify effective geoconservation strategies. While the youngest eruptive products after over 100 years of revegetation are restricted to a coastal zone, previous research has demonstrated that other young volcanic eruptions also took place in northern Savai’i in 1760 and 1902. In this study, we provide further data based on a systematic evaluation of SENTINEL satellite imagery, in combination with an ALOS-PALSAR and SRTM 30-m resolution digital terrain model-based calculation of morphometric elements, to demonstrate that the young volcanic landscape in northern Savai’i has great volcanic geodiversity and the entire region should be considered for specific geoconservation strategies. The young volcanic landforms of scoria cones in the high-altitude regions of the island, along with extensive and commonly tube-fed lava flows which have invaded the northern region of Savai’i, pose a volcanic hazard to the region. Hence, volcanic geoheritage can be the core element to enforce strong community volcanic hazard resilience. The newly proposed Samoa Geopark Project is the perfect avenue to achieve this.

【 授权许可】

CC BY