Magma Mingling in Cross-Cutting Dykes, Leh Pluton, Ladakh Batholith, NW India

Roberto Weinberg, Monash University, Australia

Jörn Kruhl Technische Universität München, Munich, Germany

 

 

Copyright 2005-2009 by Roberto Weinberg. All rights reserved. Unlimited permission to copy or use is hereby granted for non-profit driven enterprise subject to inclusion of this copyright notice and my World Wide Web URL: users.monash.edu.au/~weinberg. We would very much appreciate an email stating how this material will be used. Thanks, RW.

 

The mingling of magmas is common place in many granitic batholiths world-wide. This page shows the less common intrusion of magmas from one dyke set into magmas of another dyke set. Mafic dykes cut across (partly) solidified felsic dykes and the two magmas interact, as an early stage of mingling. Two mafic dykes intrude fault planes which displace two felsic dykes by a total of ~2.5 m in a dextral sense. All dykes are close to vertical and are exposed on nearly horizontal planes.

 


 


Field sketch, two mafic dykes cut across and displace two early intruded felsic dykes. The mafic dykes then intrude and displace the felsic dykes. Two boxes show position of photographs below.

 



a) Two mafic dykes cut across and displace an earlier felsic dyke. The mafic dyke at the centre intrudes the felsic dyke to the left, whereas the mafic dyke on the right, intrudes another part of the same felsic dyke, and both are cut by the central mafic dyke.

b) Line drawing of a)

 


 


d) Detail of the left-hand-side of a)

c) Detail of the right-hand-side of a)

 


 


e) Another part of one of the mafic dykes cutting another earlier felsic dyke.