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Tidore 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.

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.

Investigating past eruptions gives a unique opportunity to understand volcanic hazards, particularly in Indonesia, where volcanic eruptions occur frequently. Here, we present the first reconstruction of the eruptive history of the Ternate and Tidore Islands (North Maluku, Indonesia) over the past 22,000 years cal. BP, based on a new identification and characterization of past volcanic events methodological approach. This multidisciplinary study (geomorphology, tephrochronology, sedimentology, geochronology, geochemistry) constitutes the first stratigraphic and chronological continuum from volcanic deposits found in a set of fifteen sections established in Ternate, Tidore, and Maitara Islands. Sedimentological and geochemical data from tephrostratigraphy studies and radiocarbon dating suggest that these islands experienced at least four major explosive events from c. 22,000 to 740 years cal. BP. The oldest event recorded is a Plinian eruption associated with a caldera-forming eruption of Telaga volcano on Tidore Island at c. 22,000–17,500 cal. BP. A second pumiceous eruption dated at c. 18,000 cal. BP is attributed to the last Plinian eruption of Gamalama volcano on Ternate, whose current eruptive activity is mainly strombolian or phreatomagmatic. A succession of pyroclastic deposits of phreatomagmatic origin is related to the Ngade maar formation on Ternate Island, and the abundant deposits of scoria, pumice, and ash found in all sites probably occurred c. 14,500–13,000 cal. BP. No eruptions of the Kie Matubu volcano on Tidore Island have been reported by human beings since their presence in the region from the 16th century, but this study highlights two late Holocene eruptions, c. 2500 cal. BP and 740 cal. BP. This first chronostratigraphic framework from the late Pleistocene to recent eruptions in this region, sheds new light concerning the management of prediction and warning information about potential eruptions that may occur on these small volcanic islands in the future. • We reconstruct the past 22,000 years of eruptive records from Maluku archipelago. • We combine tephrostratigraphy and geochronology on Ternate and Tidore islands. • We show temporal variations of eruptive style and frequency of these volcanoes. [ABSTRACT FROM AUTHOR]