title of the thesis - Department of Geology - Queen's University

Chapter 1
Introduction
1.1 Introduction
The Himalaya-Karakoram mountain belt and adjacent Tibetan plateau are the result of the
ongoing convergence and collision of India and Asia, which initiated approximately 55-50
million years ago (Green et al., 2008; Najman et al., 2010). The Tibetan plateau is the world’s
largest and most elevated plateau, residing at a mean elevation of over 5 kilometers (Fielding et
al., 1994), and spanning from the Kunlun Mountains in central China to the Himalayan front (Fig.
1.1). The topographic front of the Tibetan plateau, also known as the Himalaya, lies between the
Indian shield to the south and the Indus-Yalu Suture to the north (Fig. 1.1). The mountain belt
trends WNW-ESE, spanning 2500 kilometers between two structural syntaxes, Nanga Parbat in
northern Pakistan and Namche Barwa in southeastern Tibet (Fig. 1.1; Hodges, 2000).
The geology of the Himalaya consists of four distinct lithotectonic domains bounded by
crustal-scale fault systems, all of which are laterally continuous across the length of the orogen
(Fig. 1.2). From north to south, these domains are the Tethyan sedimentary, Greater Himalayan,
Lesser Himalayan, and Sub-Himalayan sequences. Their bounding fault systems include the
South Tibetan detachment system, the Main Central thrust, the Main Boundary thrust, and the
Main Frontal thrust (Fig. 1.2). This study focuses on an area of northwestern Nepal, within the
two northernmost tectonostratigraphic domains, the Tethyan sedimentary sequence and Greater
Himalayan sequence, their bounding faults, the South Tibetan Detachment system (STDS), and
the Gurla Mandhata-Humla fault system (Fig. 1.2).
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