**1. Introduction**

Spatial distributions of geomorphic landforms in active regions are the results of the complex interaction of shallow and deep earth processes [1]. The imprints of these processes are reflected in the form of changes of local relief, drainage pattern, hypsometry, steepness, and channel slope relationship [2–8]. These parameters can be used to quantitatively characterize the relationship between shallow and deeper crustal structure, and geomorphic processes [1, 9]. The dry land fluvial systems of intraplate Kachchh rift basin, allow us to study the effects and linkage between brittle - ductile dynamics and surface processes on landscape evolution. The Kachchh basin evolved during the Early Jurassic, bound by Nagar Parkar Fault to the north and North Kathiawar Fault to the south (**Figure 1A**). The rifting was aborted by the trailing edge uplift during the Late Cretaceous pre-collision stage of the Indian plate, when the leading edge of the plate was slab-pulled towards the Tethyan trench [10, 14, 16]. Lateral motion during the drift stage of the plate induced horizontal stress and near vertical normal faults, which were reactivated as reverse faults during initiation of the inversion cycle, and became strike-slip faults involving divergent oblique-slip movement [10, 14, 17, 18].

Major structural features of the Kachchh region include east – west trending active faults [16, 19] (**Figure 1A**). The Wagad highland (WH) of Kachchh is bounded by the South Wagad Fault (SWF) in the south and Gedi Fault (GF) in the north comprises of Mesozoic sediments overlying a granitic basement [16]. The initiation and steadiness of dynamics support beneath Kachchh basin have been explored in several studies [10]. Earlier researchers argued that the impingement of a large intrusive body in the lower crust [19–21]. However, the fault adjacent to intrusive body at deeper depth gradually flattens close to magmatic body owing to listric nature of fault [20, 22]. The fault model proposed by [10] suggests that the GF is a sub-vertical

Evolution of Drainage in Response to Brittle - Ductile Dynamics and Surface Processes…

http://dx.doi.org/10.5772/intechopen.73653

133

The chronometric and geomorphic attributes of the GF, suggests that the region is uplifting at the rate of 0.3–1.1 mm/y during the last 9 ka [23]. The results of geomorphic processes and subsurface dynamics of GF zone can be explored by investigating how base level fall at the WH region propagates through the drainage network. The subsurface nature of faults in WH and their association with landscape evolution is still unknown. However, in present study an attempt has been made to understand brittle and ductile dynamics of fault system controlling surface landscape pattern. In this study first time we proposed an integrated sub surface model of WH by combining seismic structure (Tomograph) and surface geomorphology. In this connection we analyzed the 27 basins of WH. In particular**,** we investigated the general topographic features e.g. swath profiles, local relief and the river network (river longitudinal profiles). We employed a knickpoint celerity approach in order to provide a chronological framework to the evolution of the river network. Furthermore, we made an attempt to image subsurface fault pattern of the area using the seismological approaches such as tomoDD and focal mechanisms. The results permitted us to trace the long-term evolution of the WH, to confirm dynamic support and documenting its impact on the contrasting development of the

**2. General geomorphology and seismicity of Wagad Kachchh**

gitudinal length, these rivers cross several E-W oriented faults (**Figure 2**).

The WH is second largest uplifted block of Kachchh basin, after mainland of Kachchh, cov-

area is drained by numerous ephemeral streams; flow direction regularly spaced around the upper planation surface [23, 24]. From north to south, the WH comprises of three E-W trending active faults, namely the GF between Deshalpar and Fatehgarh area, the North Wagad Fault (NWF) north of Bharudia and the SWF between Mai and east of Chitrod

Geomorphologically the WH is divided into 3 units; (i) the upper planation surface (Mesozoic) with juvenile streams, (ii) the middle incised slopes with piedmont (Tertiary), and (iii) the low-lying areas representing Quaternary deposits [23, 25]. The upper surface represents an early Quaternary erosional event, whereas the middle incised slopes with terraces were developed during late Quaternary [26]. These two geomorphic units provide sediments to the lower peripheral areas. Suvai, Bhimguda, Narelawali, Dhadawali, Karaswali, Malan, Baniyo, and Dabhodanwari are six ephemeral rivers that flow northward and originate from the WH, following the regional slope and drain into the Great Rann of Kachchh [23]. Along their lon-

, and is bounded by GF to the north and SWF to the south [11, 16]. The

fault and gradually changing listric nature in lower crust.

drainage basins.

(**Figure 1A**).

ering an area of ~2432 km2

**Figure 1.** (A) Seismotectonic map of the Kachchh rift basin integrated with the geological map, showing the epicenters of significant earthquakes (modified after [10]). The Wagad area lies between the SWF and GF. Locations - A (Anjar), B (Bhuj), Ba (Bhachau), Br (Bharudia), Ch (Chitrod), D (Dholavira), De (Desalpar), L (Lakhpat), F (Fatehgarh) and G (Gedi); faults: NKF (North Kathiyawad Fault), KHF (Katrol Hill Fault), VF (Vigodi Fault), KMF (Kachchh Mainland Fault), SWF (South Wagad Fault), NWF (North Wagad Fault), GF (Gedi Fault), IBF (Island Belt Fault), ABF (Allah Bund Fault) and NPF (Nagar Parkar Fault); uplifts: KMU (Kachchh Mainland Uplift), PU (Patcham Uplift, KU (Khadir Uplift), BU (Bela Uplift), CU (Chorar Uplift). (B) Geological map of northern Wagad highland region [11]; shows location of earthquake epicenters. Focal mechanisms (1–16) plotted in the figure are after [12–15]. (C) CARTOSAT-DEM driven local relief map of Wagad Highland. Major and minor faults are marked by solid black line. (D) CARTOSAT DEM of the study and location of the five swath profiles; 1–5) swath profiles show the trends of the maximum, minimum and mean topography of the Wagad region. **Figure 1A** and **1B** *have been digitized in Surfer 14 software, while, we used MICRO-DEM 10 software for generation of* C and D*, and final editing has been done in golden software Surfer 14*.

Major structural features of the Kachchh region include east – west trending active faults [16, 19] (**Figure 1A**). The Wagad highland (WH) of Kachchh is bounded by the South Wagad Fault (SWF) in the south and Gedi Fault (GF) in the north comprises of Mesozoic sediments overlying a granitic basement [16]. The initiation and steadiness of dynamics support beneath Kachchh basin have been explored in several studies [10]. Earlier researchers argued that the impingement of a large intrusive body in the lower crust [19–21]. However, the fault adjacent to intrusive body at deeper depth gradually flattens close to magmatic body owing to listric nature of fault [20, 22]. The fault model proposed by [10] suggests that the GF is a sub-vertical fault and gradually changing listric nature in lower crust.

**1. Introduction**

132 Tectonics - Problems of Regional Settings

Spatial distributions of geomorphic landforms in active regions are the results of the complex interaction of shallow and deep earth processes [1]. The imprints of these processes are reflected in the form of changes of local relief, drainage pattern, hypsometry, steepness, and channel slope relationship [2–8]. These parameters can be used to quantitatively characterize the relationship between shallow and deeper crustal structure, and geomorphic processes [1, 9]. The dry land fluvial systems of intraplate Kachchh rift basin, allow us to study the effects and linkage between brittle - ductile dynamics and surface processes on landscape evolution. The Kachchh basin evolved during the Early Jurassic, bound by Nagar Parkar Fault to the north and North Kathiawar Fault to the south (**Figure 1A**). The rifting was aborted by the trailing edge uplift during the Late Cretaceous pre-collision stage of the Indian plate, when the leading edge of the plate was slab-pulled towards the Tethyan trench [10, 14, 16]. Lateral motion during the drift stage of the plate induced horizontal stress and near vertical normal faults, which were reactivated as reverse faults during initiation of the inversion cycle, and became strike-slip faults

**Figure 1.** (A) Seismotectonic map of the Kachchh rift basin integrated with the geological map, showing the epicenters of significant earthquakes (modified after [10]). The Wagad area lies between the SWF and GF. Locations - A (Anjar), B (Bhuj), Ba (Bhachau), Br (Bharudia), Ch (Chitrod), D (Dholavira), De (Desalpar), L (Lakhpat), F (Fatehgarh) and G (Gedi); faults: NKF (North Kathiyawad Fault), KHF (Katrol Hill Fault), VF (Vigodi Fault), KMF (Kachchh Mainland Fault), SWF (South Wagad Fault), NWF (North Wagad Fault), GF (Gedi Fault), IBF (Island Belt Fault), ABF (Allah Bund Fault) and NPF (Nagar Parkar Fault); uplifts: KMU (Kachchh Mainland Uplift), PU (Patcham Uplift, KU (Khadir Uplift), BU (Bela Uplift), CU (Chorar Uplift). (B) Geological map of northern Wagad highland region [11]; shows location of earthquake epicenters. Focal mechanisms (1–16) plotted in the figure are after [12–15]. (C) CARTOSAT-DEM driven local relief map of Wagad Highland. Major and minor faults are marked by solid black line. (D) CARTOSAT DEM of the study and location of the five swath profiles; 1–5) swath profiles show the trends of the maximum, minimum and mean topography of the Wagad region. **Figure 1A** and **1B** *have been digitized in Surfer 14 software, while, we used MICRO-DEM 10 software for* 

involving divergent oblique-slip movement [10, 14, 17, 18].

*generation of* C and D*, and final editing has been done in golden software Surfer 14*.

The chronometric and geomorphic attributes of the GF, suggests that the region is uplifting at the rate of 0.3–1.1 mm/y during the last 9 ka [23]. The results of geomorphic processes and subsurface dynamics of GF zone can be explored by investigating how base level fall at the WH region propagates through the drainage network. The subsurface nature of faults in WH and their association with landscape evolution is still unknown. However, in present study an attempt has been made to understand brittle and ductile dynamics of fault system controlling surface landscape pattern. In this study first time we proposed an integrated sub surface model of WH by combining seismic structure (Tomograph) and surface geomorphology. In this connection we analyzed the 27 basins of WH. In particular**,** we investigated the general topographic features e.g. swath profiles, local relief and the river network (river longitudinal profiles). We employed a knickpoint celerity approach in order to provide a chronological framework to the evolution of the river network. Furthermore, we made an attempt to image subsurface fault pattern of the area using the seismological approaches such as tomoDD and focal mechanisms. The results permitted us to trace the long-term evolution of the WH, to confirm dynamic support and documenting its impact on the contrasting development of the drainage basins.
