Volcanic Geoheritage and Geotourism

*Updates in Volcanology – Transdisciplinary Nature of Volcano Science*

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**329**

**1. Introduction**

**Chapter 14**

*and Dan Tormey*

**Abstract**

Volcanoes: Identifying and

Large to Small Scale

Evaluating Their Significant

*Margaret Brocx, Vic Semeniuk, Tom J. Casadevall* 

Geoheritage Features from the

Across the globe, volcanoes and volcanic terrains present one of the most complex geological systems on Earth that, depending on magma type, viscosity, and water and gas content, form a diverse range of products in terms of geomorphology, lithologic suites, structures, and stratigraphy. In broad terms, magmas, with their diagnostic composition, derive from specific tectonic settings, *e.g.*, basalt-dominated oceanic crusts, acidic magma from continental plates, and

andesitic convergent-plate margins. In addition to magma composition and volcanic rock types, there is a wide range of volcanic products, manifest at all scales, dependent on how magma interacts with the Earth's surface, varying, for instance, from lava flows such as vesicular lava beds and flow-banded to flow-laminated lava beds, to breccias, tephra (ejecta) deposits, and bombs, amongst others, each commonly with their diagnostic small-scale lithological/structural features. This wealth of rock types, stratigraphy, and structures linked to geologic setting, potentially has geoheritage significance, and we provide here methods tailored for volcanoes and volcanic rocks of identifying, classifying and evaluating the complex and heterogeneous nature of volcanoes so that the full complement of their geology for a given region can be appreciated and incorporated into thematic geoparks, Nature Reserves and protected areas. For sites of geoheritage significance, we present (1) a globally-applicable Geoheritage Tool-kit to systematically identify volcanic geoheritage sites, (2) a technique to classify/categorise geoheritage sites, and (3) a semiquantitative method to evaluate the geoheritage significance of volcanic sites.

**Keywords:** volcanoes, volcanic geology, geoheritage, geoconservation, geoparks

Volcanoes and volcanic terrains are one of the most complex geological systems on Earth forming a range of products from the megascale and large scale to small scale that have varying geological significance. Of necessity, the ensuing text is a brief summary of a very complex and diverse subject matter, presented to a level sufficient to convey their comparative diversity and scale of expression for purposes
