Published 1988 | Version v1
Report

Eruptive viscosity and volcano morphology

Description

Terrestrial central volcanoes formed predominantly from lava flows were classified as shields, stratovolcanoes, and domes. Shield volcanoes tend to be large in areal extent, have convex slopes, and are characterized by their resemblance to inverted hellenic war shields. Stratovolcanoes have concave slopes, whereas domes are smaller and have gentle convex slopes near the vent that increase near the perimeter. In addition to these differences in morphology, several other variations were observed. The most important is composition: shield volcanoes tend to be basaltic, stratovolcanoes tend to be andesitic, and domes tend to be dacitic. However, important exceptions include Fuji, Pico, Mayon, Izalco, and Fuego which have stratovolcano morphologies but are composed of basaltic lavas. Similarly, Ribkwo is a Kenyan shield volcano composed of trachyte and Suswa and Kilombe are shields composed of phonolite. These exceptions indicate that eruptive conditions, rather than composition, may be the primary factors that determine volcano morphology. The objective of this study is to determine the relationships, if any, between eruptive conditions (viscosity, erupted volume, and effusion rate) and effusive volcano morphology. Moreover, it is the goal of this study to incorporate these relationships into a model to predict the eruptive conditions of extraterrestrial (Martian) volcanoes based on their morphology

Additional details

Publishing Information

Imprint Title
NASA MEVTV program working group meeting: Volcanism on Mars
Journal Page Range
p. 1-3.
Report number
N--88-30487

Conference

Title
volcanism on Mars.
Acronym
NASA MEVTV program working group meeting
Dates
27-30 Jun 1988.
Place
Oahu, HI (USA).

INIS

Country of Publication
United States
Country of Input or Organization
United States
INIS RN
20027982
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Resource subtype / Literary indicator
Conference
Descriptors DEI
DIFFUSION; GEOLOGIC MODELS; GEOMORPHOLOGY; LAVA; ORGANIZING; VISCOSITY; VOLCANOES; VOLUME
Descriptors DEC
GEOLOGY; IGNEOUS ROCKS; ROCKS