Scott, B.J.; Potter, S.H. 2014 Catalogue of historical eruptive activity and volcanic unrest at Mt. Tongariro : 1846-2013 . Lower Hutt, N.Z.: GNS Science. GNS Science report 2014/20 70 p.
Abstract: The 6 August and 21 November 2012 eruptions from Upper Te Maari have heightened interest in past activity at Tongariro Volcanic Centre. In recent years considerably more interest has also been taken in aspects of the hazards presented by volcanic eruptions and the risk to people who may be affected by the eruptions. Several studies have used statistical approaches to look at these problems. To enable this type of study at Tongariro an eruption catalogue is required. This report presents a new look at unrest and eruptive activity at Tongariro, including other vents such as Red Crater and presents a detailed historical chronology of eruptive activity and volcanic unrest. To compile this report, historical newspaper collections, unpublished science reports, published papers, parliamentary reports and popular writings have been examined. This research has significantly increased our understanding of both small and larger events at Tongariro and the occurrence of volcanic unrest. This compilation (since 1846) has shown there has been substantially more unrest and eruptive activity than previously appreciated for the Tongariro Volcanic Centre (exclusive of Mt Ngauruhoe). In particular, activity at Red Crater has previously been underestimated. However many aspects of small scale activity and lower levels of unrest remain unreported. Eruptive activity and unrest is recognised from 1846. Eruptions are now thought to have occurred at Mt. Tongariro in 1869, 1892, 1896-97, 1899, 1926, 1927, 1934 and 2012. Eruptions also potentially occurred in 1846, 1855, 1886, and 1928. New eruption recurrence rates are derived from this catalogue, with the baseline return period for the onset of an eruption episode calculated to be 0.07 per year (if 1896-97 and 2012 are considered as one episode each, and all others separately), and the maximum eruption rate within an eruption episode is 18 per year (1896-97). These new data contribute towards risk assessments for future eruptions at Mt. Tongariro. (auth)