Editing Lake Toba (section)

===More recent activity===
Since the major eruption ~70,000 years ago, eruptions of smaller magnitude have also occurred at Toba. The small cone of Pusukbukit formed on the southwestern margin of the caldera and lava domes. The most recent eruption may have been at Tandukbenua on the northwestern caldera edge, suggested by a lack of vegetation that could be due to an eruption within the last few hundred years.<ref>{{cite web|url=http://www.volcanodiscovery.com/volcano-tours/volcanoes/indonesia/sumatra/toba/|title=Toba volcano (Indonesia, Sumatra)|publisher=VolcanoDiscovery.com}}<!-- Bot generated title --></ref>

Some parts of the caldera have shown uplift due to partial refilling of the [[magma chamber]], for example, pushing [[Samosir|Samosir Island]] and the [[Uluan Peninsula]] above the surface of the lake. The lake sediments on Samosir Island show that it has risen by at least {{convert|450|m|0|abbr=on}}<ref name=OregonState/> since the cataclysmic eruption. Such uplifts are common in very large calderas, apparently due to the upward pressure of below-ground [[magma]]. Toba is probably the largest resurgent caldera on Earth. Large [[earthquake]]s have recently occurred in the vicinity of the volcano, notably in 1987 along the southern shore of the lake at a depth of {{convert|11|km|abbr=on}}.<ref>{{cite web|url=https://earthquake.usgs.gov/eqcenter/eqarchives/significant/sig_1987.php|title=Significant Earthquakes of the World|publisher=United States Geological Survey (USGS)}}<!-- Bot generated title --></ref> Such earthquakes have also been recorded in 1892, 1916, and 1920–1922.<ref name="OregonState">[https://link.springer.com/article/10.1007/BF00280226 Stratigraphy of the Toba Tuffs and the evolution of the Toba Caldera Complex, Sumatra, Indonesia]</ref>

In 2016, a study revealed that the Toba Supervolcano has a magma chamber containing {{convert|50000|km3|mi3}} of eruptible magma, about {{convert|30|-|50|km|mi}} underground.<ref name="Koulakov_etal_2016">{{cite journal | title=The feeder system of the Toba supervolcano from the slab to the shallow reservoir | first1=I. | last1=Koulakov | first2=E. | last2=Kasatkina | first3=N.M. | last3=Shapiro | first4=C. | last4=Jaupart | first5=A. |last5=Vasilevsky | first6=S. | last6=El Khrepy | first7=N. | last7=Al-Arifi | first8=S. | last8=Smirnov | journal=Nature Communications | year=2016 | volume=7| page=12228 | doi=10.1038/ncomms12228 | pmid=27433784 | pmc=4960321 | bibcode=2016NatCo...712228K }}</ref> This makes the supervolcano's magma chamber more than four times larger than the volume of [[Lake Superior]] in North America, and also larger than the magma chamber underneath [[Yellowstone Caldera|Yellowstone]].<ref name="bigger">{{cite web|url=https://www.iflscience.com/environment/the-toba-supervolcano-has-a-bigger-underground-magma-chamber-than-yellowstone/all/|title=The Toba Supervolcano Has A Bigger Underground Magma Chamber Than Yellowstone|website=iflscience.com|author=Robin Andrews|publisher=IFL Science!|date=20 July 2016|access-date=2 April 2021}}</ref>

Lake Toba lies near the [[Great Sumatran fault]], which runs along the centre of Sumatra in the [[Great Sumatran fault|Sumatra fracture zone]].<ref name=OregonState/> The volcanoes of Sumatra and Java are part of the [[Sunda Arc]], a result of the northeasterly movement of the [[Indo-Australian plate]], which is sliding under the eastward-moving [[Eurasian plate]]. The [[subduction]] zone in this area is very active: the seabed near the west coast of Sumatra has had several major earthquakes since 1995, including the 9.1 [[2004 Indian Ocean earthquake and tsunami|2004 Indian Ocean earthquake]] and the 8.7 [[2005 Nias–Simeulue earthquake]], the epicenters of which were around {{convert|300|km|abbr=on}} from Toba.{{citation needed|date=August 2024}}