Ref ID:	22974
Ref Type:	Book Section
Authors:	Hada, S. Bunopas, S. Ishii, K. Yoshikura, S.
Title:	Rift-drift history and the amalgamation of Shan-Thai and Indochina/East Malaya Blocks
Date:	1999
Source:	Gondwana Dispersion and Asian Accretion <i>IGCP 321 Final Results Volume</i>
Place of Publication:	Rotterdam
Publisher:	A. A. Balkema
Abstract:	The rocks of the Sa Kaeo-Chanthaburi segment of the Nan-Chanthaburi suture zone between the Shan-Thai and Indochina/East Malaya continental blocks in Thailand comprise two parallel belts a western belt of chert-clastic sequence, and an eastern belt of serpentine melange. In order to understand the nature of the suture zone and to build up its tectonic sequence, we have investigated the lithology, age, stratigraphy, structure and relationships of their components. The core of all the questions is the radiolarian biostratigraphy and fusulinacean faunas in the suture zone and the continental blocks. Indochina/East Malaya had rifted away from northeastern margin of Gondwanaland by the Late Devonian. It is characterized by the mid-Permian fusulinids of the <i>Lepidolina</i> territory. In contrast, the Shan-Thai continental block had rifted from Gondwanaland by latest Permian time and its fusulinacean faunas are characterized by species of <i> Misellina- Maclaya- Neoschwagerina</i> lineage of the <i>Yabeina</i> territory in the mid-Permian. However, it belongs to another lineage of <i> Colania- Lepidolina</i> evolutionary lineage in the late md-Permian. the change of biofacies of the Shan-Thai block indicates the northward drift of the block crossing the equator. Middle Triassic Radiolaria have been obtained form red chert clasts of the red bed which unconformably overlies the serpentinite melange of the suture zone. Accordingly, the Shan-Thai block moved further towards the Indochina/East Malaya block and eventually collided with its southern margin in the Late Triassic.
Date Created:	2/24/2012
Editors:	Metcalfe, I. Jishun, Ren Charvet, J. Hada, S.
Page Start:	67
Page End:	87