what kind of mantle activity causes volcanism on hawaii
convection
title: Hawaiian eruption text: Hawaiian eruption A Hawaiian eruption is a type of volcanic eruption where lava flows from the vent in a relatively gentle, low level eruption; it is so named because it is characteristic of Hawaiian volcanoes. Typically they are effusive eruptions, with basaltic magmas of low viscosity, low content of gases, and high temperature at the vent. Very small amounts of volcanic ash are produced. This type of eruption occurs most often at hotspot volcanoes such as Kīlauea on Hawaii's big island and in Iceland, though it can occur near subduction zones (e.g. Medicine Lake Volcano in California, United States) and title: Hawaii hotspot text: Hawaii hotspot The Hawaii hotspot is a volcanic hotspot located near the namesake Hawaiian Islands, in the northern Pacific Ocean. One of the most well-known and heavily studied hotspots in the world, the Hawaii plume is responsible for the creation of the Hawaiian – Emperor seamount chain, a chain of volcanoes over 5,800 kilometres (3,600 mi) long. Four of these volcanoes are active, two are dormant, and more than 123 are extinct, many having since been ground beneath the waves by erosion as seamounts and atolls. The chain extends from south of the island of Hawaii to the edge of title: Hawaiian Islands text: hotspot in the Earth's mantle at a rate of approximately per million years. Thus, the southeast island is volcanically active, whereas the islands on the northwest end of the archipelago are older and typically smaller, due to longer exposure to erosion. The age of the archipelago has been estimated using potassium-argon dating methods. From this study and others, it is estimated that the northwesternmost island, Kure Atoll, is the oldest at approximately 28 million years (Ma); while the southeasternmost island, Hawaii, is approximately 0.4 Ma (400,000 years). The only active volcanism in the last 200 years has been on the title: Timeline of volcanism on Earth text: sulfuric acid), which are very reflective; ash aerosol on the other hand absorbs Ultraviolet. Global cooling through volcanism is the sum of the influence of the global dimming and the influence of the high albedo of the deposited ash layer. The lower snow line and its higher albedo might prolong this cooling period. Bipolar comparison showed six sulfate events: Tambora (1815), Cosigüina (1835), Krakatoa (1883), Agung (1963), and El Chichón (1982), and the 1808/1809 mystery eruption. And the atmospheric transmission of direct solar radiation data from the Mauna Loa Observatory (MLO), Hawaii (19°32'N) detected only five eruptions: But very large title: Hawaiian Islands text: southeastern island, Hawaii, and on the submerged but growing volcano to the extreme southeast, Loihi. The Hawaiian Volcano Observatory of the USGS documents recent volcanic activity and provides images and interpretations of the volcanism. Kīlauea has been erupting nearly continuously since 1983. Almost all of the magma of the hotspot has the composition of basalt, and so the Hawaiian volcanoes are composed almost entirely of this igneous rock. There is very little coarser-grained gabbro and diabase. Nephelinite is exposed on the islands but is extremely rare. The majority of eruptions in Hawaii are Hawaiian-type eruptions because basaltic magma is relatively