McPhie J., Doyle M., Allen R. Volcanic Textures. A guide to the interpretation of textures in volcanic rocks

Centre for Ore Deposit and Exploration Studies University of Tasmania, 1993. — 198 p.The book provides a practical guide to the description and interpretation of important textures in lavas, syn-volcanic intrusions and a wide variety of volcaniclastic deposits.Acknowledgements.
Interpreting textures: terminology and techniques.
The imprint of genetic processes on textures in volcanic deposits.
Emphasis and organisation.
An approach to the genetic interpretation of textures in volcanic deposits.
Two textural categories: coherent volcanic and volcaniclastic.
Descriptive nomenclature for coherent volcanic and volcaniclastic deposits.
Graphic logging technique.
Important textures and structures.
A summary of the essential features of the seafloor massive sulfide environment.
Introduction to the Mount Read Volcanics.
Common components, textures and structures in volcanic deposits.
Phenocrysts and porphyritic texture.
Crystals and crystal fragments.
Vesicles.
Volcanic glass.
Devitrification.
Spherulites.
Lithophysae.
Micropoikilitic texture.
Perlite.
Pumice and scoria.
Achneliths, bombs and blocky juvenile clasts.
Glass shards.
Lithic fragments.
Accretionary lapilli.
Fiamme and pseudofiamme.
Flow foliations.
Joints.
Lavas, syn-volcanic intrusions and related volcaniclastic deposits.
Autobreccia.
Talus.
Hyaloclastite.
Peperite.
Pillow lavas.
Subaqueous basaltic lava flows.
Subaqueous silicic lava flows, domes and syn-volcanic intrusions.
Subaqueous silicic lava flows and extrusive domes.
Subaqueous partly extrusive cryptodomes.
Subaqueous syn-volcanic sills and dykes.
Volcaniclastic deposits associated with silicic lava dome eruptions in shallow water.
Case Study: Partly extrusive, submarine, dacite cryptodome, Sock Creek South, western Tasmania.
Subaerial silicic lava flows and domes.
Subaerial basaltic lava flows.
Andesitic lavas.
Pyroclastic, resedimented volcaniclastic and volcanogenic sedimentary deposits.
Genetic classification of volcaniclastic deposits.
Explosive eruptions and pyroclastic deposits.
Explosive magmatic eruptions.
Phreatomagmatic eruptions.
Phreatic or steam eruptions.
Resedimented syn-eruptive volcaniclastic deposits.
Volcanogenic sedimentary deposits.
Transport and deposition of volcaniclastic particles.
Mass movement and mass-flow deposits.
Primary pyroclastic flow deposits.
Definition and genesis.
Transport and depositional processes.
Characteristics of pyroclastic flow deposits.
Components.
Types of deposits.
Textures and internal organisation of depositional units.
Grade.
Geometry and aspect ratio.
Dimensions of pyroclastic flow deposits.
Proximal to distal textural variations.
Compositional zonation.
Significance of pyroclastic flow deposits.
Subaqueously-emplaced pyroclast-rich mass-flow deposits.
Transgression of shorelines by pyroclastic flows.
Welded ignimbrite interbedded with submarine sedimentary sequences.
Non-welded, pyroclast-rich, submarine mass-flow deposits.
Significance.
Water-supported and gravity-driven volcaniclastic mass flows and their deposits.
Turbidites.
Low-density turbidity currents.
High-density turbidity currents.
Volcaniclastic turbidites.
Significance.
Cohesive debris flows, volcaniclastic debris flows and their deposits.
Lahars.
Volcaniclastic grain-flow deposits.
Volcanic slides, volcanic debris avalanches and their deposits.
Massive sulfide clast-bearing submarine volcaniclastic mass-flow deposits.
Traction transport and volcaniclastic traction current deposits.
Tractional sedimentary structures.
Characteristics.
Significance.
Pyroclastic surges and their deposits.
Characteristics.
Dimensions of pyroclastic surge deposits.
Significance.
Suspension transport and volcaniclastic suspension deposits.
Pyroclastic fall deposits.
Characteristics.
Water-settled pyroclastic fall deposits.
Suspension sedimentation associated with subaqueous volcaniclastic mass flows.
Sedimentation in volcanic terranes.
Alteration: an integral part of textural evolution.
Alteration events in the Mount Read Volcanics.
Alteration of lavas, shallow intrusions and related autoclastic breccias.
Original texture.
Glassy margins.
Mixed glassy and spherulitically devitrified zones.
Spherulitic or microlitic cores of lavas and shallow intrusions.
General trends and implications.
Alteration of pumiceous deposits.
Originally glassy and permeable deposits.
Phyllosilicate alteration.
Two-phase feldspar and phyllosilicate alteration.
General trends and implications.