Date (Creation)

2024-11-13

Citation identifier

http://data.bgs.ac.uk/id/dataHolding/13608316

Point of contact

Organisation name	Individual name	Electronic mail address	Role
University of Edinburgh	Eric Breard	not available	Originator
University of Oregon	Josef Dufek	not available	Originator
Istituto Nazionale di Geofisica e Vulcanologia	Matteo Cerminara	not available	Originator
British Geological Survey	Enquiries	not available	Distributor
British Geological Survey	Enquiries	not available	Point of contact

Maintenance and update frequency

notApplicable

GEMET - INSPIRE themes, version 1.0

• Geology

BGS Thesaurus of Geosciences

• Pyroclastic rocks

• Citable Data

• NGDC Deposited Data

• Lava flows

• Rheology

• Volcanoes

dataCentre

• NGDC Deposited Data
• Citable Data

Keywords

• NERC_DDC

Access constraints

Other restrictions

Other constraints

restricted

Other constraints

The dataset has been formally approved by BGS for access by external clients under a BGS Digital Data Licence, issued via BGS's IPR Section. The dataset must not be provided to, or be accessible by, an external client until the IPR Section confirms that signed licence documentation is in place. Refer to the IPR Section (DigitalLE@bgs.ac.) if further advice is required.. Constraint applies until 2025-06-01

Use constraints

Other restrictions

Other constraints

The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused.

Other constraints

Either: (i) the dataset is made freely available, e.g. via the Internet, for a restricted category of use (e.g. educational use only); or (ii) the dataset has not been formally approved by BGS for access and use by external clients under licence, but its use may be permitted under alternative formal arrangements; or (iii) the dataset contains 3rd party data or information obtained by BGS under terms and conditions that must be consulted in order to determine the permitted usage of the dataset. Refer to the BGS staff member responsible for the creation of the dataset if further advice is required. He / she should be familiar with the composition of the dataset, particularly with regard to 3rd party IPR contained in it, and any resultant use restrictions. This staff member should revert to the IPR Section ( ipr@bgs.ac.uk) for advice, should the position not be clear.

Language

English

Topic category

• Geoscientific information

Begin date

2023-05-01

End date

2023-12-01

Distribution format

Name	Version
DAT	witheld
VELOCITY* and FORCES* files	witheld

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey	Enquiries	not available	Distributor

OnLine resource

Protocol	Linkage	Name
WWW:DOWNLOAD-1.0-http--download	https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item186552	Data

OnLine resource

Protocol	Linkage	Name
WWW:LINK-1.0-http--related	https://doi.org/10.5285/3f772a04-bab2-4952-99ef-49c54e8032de	Citation Information - Digital Object Identifier (DOI)

Hierarchy level

Non geographic dataset

Other

non geographic dataset

Statement

Pyroclastic Density Currents (PDCs) are among the most hazardous geological phenomena, posing challenges for predicting their impacts during eruptions. PDCs are complex, multiphase flows where density stratification significantly influences mixing, deposition, and runout. Simplified models like box models and depth-averaged approaches often assume vertically well-mixed currents, but the impact of these assumptions on mobility has been a focus of recent studies. To explore the effects of density stratification and buoyancy reversal on PDC behavior, we conducted 3D multiphase flow simulations based on heated particle-laden saline water experiments. Results showed distinct behavior for buoyant and non-buoyant currents: buoyant currents exhibited a unique density profile with a minimum at the nose, while non-buoyant currents followed typical Rousean stratification. These differences arise from interactions between density stratification and thermal buoyancy, which affect flow runout. Our findings reveal that fluid buoyancy slows particle settling, enhances vertical mixing, and limits spanwise spreading, aligning with experimental observations. However, the bulk Richardson number fails to accurately describe entrainment in these flows, suggesting a need to refine parameterization in depth-averaged models to better capture the transient nature of PDCs and improve hazard predictions.

Metadata

File identifier

27cf51c5-373e-4ed6-e063-0937940a852b XML

Metadata language

English

Hierarchy level

Non geographic dataset

Hierarchy level name

non geographic dataset

Date stamp

2026-01-14

Metadata standard name

UK GEMINI

Metadata standard version

2.3

Metadata author

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey		enquiries@bgs.ac.uk	Point of contact

Dataset URI

http://data.bgs.ac.uk/id/dataHolding/13608316