Ecotourism in a Hazardous Small-Volcanic Island: Tidore Island, Indonesia

Abstract Being known as a small island with the highest volcano in North Maluku Province, Tidore Island is also famed for its exotic ecotourism potential. There are many benefits for areas that have good ecotourism potential, but it is necessary to consider the potential for local disasters. Kie Matubu Volcano is currently in a dormant status and is likely to be active at any time. Regional planning and disaster mitigation should thus go hand in hand, but the complexity of the geographical conditions of a small island requires various prior analyses. This research aims to integrate ecotourism mentioned in Regional Planning with disaster mitigation action in Tidore Island. Combining spatial analysis and social vulnerability can provide an overview of the integration planning and disaster management in this small volcanic island to improve community resilience. However, it still calls for some actions to develop ecotourism areas that co-occur with disaster mitigation efforts. Several villages with high social vulnerability in the western, southern, and eastern parts of the island require additional infrastructures (e.g., port terminals) and functional disaster evacuation facilities as the important aspect while disaster occurs

Geomorphology of the small island of Tidore and Hiri (North Maluku, Indonesia)

International audienceTidore and Hiri Islands in North Maluku Province is the result of a complex tectonic setting. In contrast with Ternate Island and its well-known volcano, Gamalama volcano, there is still a lack of research about volcanic information or volcanic landform in Tidore and Hiri Islands. Even though the two islands also have volcanoes, i.e., Hiri and Tidore/Kiematubu volcano. This study aims to provide geomorphological information, especially in Tidore and Hiri Islands, since this information is hard to find whereas it is very important to disaster mitigation and landuse planning. We used remote sensing images, digital elevation models (DEM), and geological maps to classify geomorphological information of the small island of Tidore and Hiri in the North Maluku based on geomorphological aspects, i.e., morphology, morphogenesis, morpho-chronology, and morpho-arrangement. As a volcanic island, the slope in Tidore and Hiri Island is dominated by a slightly steep (8°-16°) and a steep slope (16°-35°), while the relief is dominated by hills and mountainous. Volcanic landforms on Tidore and Hiri Islands are characterized by relatively symmetrical cone-shaped volcanic cones, which are accumulations of falling pyroclastic material and lava ejected from magma vents. Volcanic islands include the case of Tidore and Hiri Island have radial centrifugal river flow patterns. The material on Tidore and Hiri Islands is dominated by Holocene volcanic rocks. In Tidore, there is alluvial material on the west and east coasts of the island. This study result also can be developed into more detailed geomorphological maps, or landscape evolution in a volcanic island, or spatial planning

Assessment of Social Vulnerability to Kiematubu Volcano in Tidore Island, North Maluku

Kiematubu volcano is often considered as non-volcanic, even though it consists of basalt material, since it has never erupted before. In fact, that small volcanic islands have a high risk due to their restriction on means and resources. The study aims to assess the social vulnerability of the community in Tidore Island that may be exposed to the eruption of the Kiematubu volcano. There has not been previous research in Tidore Island regarding volcanic vulnerability yet. The social vulnerability is an initial assessment of disaster management, which will affect in optimizing community’s capacity then minimizing the disaster impacts. Social parameter of demographic condition, health facilities, and education facilities was weighted to assess social vulnerability. The result shows that the social vulnerability class of Tidore Island is dominantly low, approximately 80%, the rest is middle and high, with a percentage of 13% and 7%, respectively. Mostly, the low vulnerable villages are due to less population density. However, the highly vulnerable villages, Gamtufkange and Indonesiana, consist of very high and high population density. The southeast part of Tidore Island, where both villages are situated, is the center of human activities, such as governmental, trades, and education

Avalanche de débris et événement éruptif associé au volcan Samalas, Lombok, Indonésie

International audienceWe propose a vast area in the middle of Lombok, Indonesia, dominated by hummock hills, is a debris avalanche deposit (DAD). We define this > 500 km2 area as Kalibabak DAD that may originate from Samalas volcano. No descriptions of the morphology, stratigraphy, mechanism, and age of this DAD have yet been reported; this contribution bridges this research gap. Here we present morphological and internal architecture analysis, radiocarbon dating, paleotopographic modeling, and numerical simulation of the DAD. We also present geospatial data e.g., topographical and geological maps, digital elevation models (DEMs), satellite imagery – in combination with stratigraphic data constructed from field surveys, archived data, and electrical resistivity data. Results show that the DAD was formed by a sector-collapse of Samalas volcano and covers an area of 535 km2, with a deposit width of 41 km and a runout distance up to 39 km from the source. The average deposit thickness is 28 m, reaching a measured local maximum of 58 m and a calculated volume of ~ 15 km3. Andesitic breccia boulders and a sandy matrix dominate the deposit. Using ShapeVolc, we reconstructed the pre-DAD paleotopography and then used the reconstructed DEM to model the debris avalanche using VolcFlow. The model provides an estimate of the flow characteristics, but the extent of the modelled deposit does not match the present-day deposit, for at least two reasons: (i) the lack of information on the previous edifice topography that collapsed, and (ii) limited understanding of how DADs translate across the landscape. Fourteen radiocarbon dating samples indicate that the DAD was emplaced between 7,000–2,600 BCE. The DAD's enormous volume, vast extent and poorly weathered facies strongly suggest that it was not triggered by a Bandai-type debris avalanche (solely phreatic eruption), but more likely by a Bezymianny-type (magmatic eruption). This event was potentially triggered by a sub-Plinian or Plinian eruption (high eruption column with umbrella-like cloud) dated ~ 3,500 BCE, which produced the Propok pumice fall deposits

A 22,000-year tephrostratigraphy record of unidentified volcanic eruptions from Ternate and Tidore islands (North Maluku, Indonesia)

International audienc

A 22,000-year tephrostratigraphy record of unidentified volcanic eruptions from Ternate and Tidore islands (North Maluku, Indonesia)

International audienc