Skip to main content

Alteration processes and products of acid pyroclastic rocks in Bulgaria and Slovakia

Buy Article:

$13.61 plus tax (Refund Policy)

Abstract:

The genesis of the products of the alteration of acid pyroclastic material is discussed and interpreted on the basis of the distribution, sedimentation conditions, post-sedimentation activity, mineral and chemical compositions of pyroclastic deposits in Bulgaria and Slovakia.

It is found that the disordered nonequilibrium nature of the volcanic glass induces a diagenetic devitrification of the tuffs and formation of clinoptilolitic, adularia-cristobalite and bentonite rocks. With increasing temperature, the volcanic glass tends forward a stable state through a series of zeolite mineral associations: clinoptilolite-mordenite-analcime-feldspar. The change in mineral composition of this series of rocks occurs without a change in the chemical composition of the rocks, which could be explained by the closed nature of zeolite systems. The formation of bentonites is associated with the removal of alkaline ions under diagenetic conditions, while the formation of halloysite rocks is caused by hydrothermal activity.

Keywords: ACID PYROCLASTIC ROCKS; ALTERATION; BULGARIA; DIAGENESIS; SLOVAKIA; ZEOLITIZATION

Document Type: Research Article

DOI: http://dx.doi.org/10.1180/claymin.2011.046.2.279

Publication date: June 1, 2011

More about this publication?
minsoc/cm/2011/00000046/00000002/art00012
dcterms_title,dcterms_description,pub_keyword
6
5
20
40
5

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
UA-1313315-23
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more