My two favorite strikes slip faults in India as rendered by Cartosat 1 Digital Elevation Model-
1) Yamuna Left Lateral Fault-
Source: Cartosat 1 DEM National Remote Sensing Center, ISRO
You can see that the Siwalik hills are breached by the Yamuna and dislocated in a left lateral sense, i.e. one would have to turn left to follow the narrow marker rock bed across the fault.
From a previous post on this fault-
This fluvial wedge over the last half a million years has been deformed into the Siwalik mountains. These mountains form broad synclines and tight anticlines cut by north dipping thrust faults, a result of the continuing compression of the sediment wedge. The southernmost of these thrusts which brings into tectonic contact the anticlinal Frontal Range of the Siwaliks over the alluvial plains in called the Himalayan Frontal Thrust (HFT).
The HFT is broken into segments and the amount of displacement along these segments or thrust blocks is unequal. For example the blocks west of the Yamuna and east of the Ganga have moved southwards with an opposite sense of movement relative to the central block known as the Dun block. To view this, turn on labels and pan southeastwards in embeddable map below until the town of Haridwar where the Ganga enters the plains.
Thus the Yamuna fault has a left lateral sense of movement while the Ganga fault has a right lateral sense of movement. These faults can be thought of as lateral ramps of the HFT accommodating the displacement caused by the southwards movement of the HFT blocks.
Structural considerations indicate that during the last 0.5 my there has been about 8 km of displacement along the Yamuna and Ganga faults, a slip rate of approx. 16 mm year.
The Digital Elevation Model also brings out beautifully the Quaternary alluvial fans with tiers of river terraces deposited in the valley between the Siwaliks and the Lesser Himalayas and the intricate drainage on the southern slopes of the Siwalik frontal range.
2) Gani Kalava Fault-
This too has a left lateral movement and has a prolonged history of being reactived during different phases of sedimentation in the Proterozoic Cuddapah Basin of south India. I did my M.Sc dissertation on this area, concentrating on the asymmetric anticline with a gentler dipping southern limb and a nearly vertical dipping northern limb located south of Gani village.
Source: Cartosat 1 DEM, National Remote Sensing Center, ISRO
From a previous post on this fault-
The feature is an ENE plunging asymmetric anticline with spectacular dip slopes of quartz arenites making up the southern limb of the fold and left-lateral movement along a regional fault steepening the northern limb of the fold. There is some copper mineralization along the fault. The Cuddapah basin is an intra-cratonic basin which was filled up in several depositional mega cycles. Sections of two of these mega cycles are exposed in this area. The older mega cycle comprising the Cuddapah subgroup is exposed in the core of the anticline. An angular unconformity separates the older cycle from the younger Kurnool cycle (sub group) which is exposed along the limbs.
Brown arrows shows the offset marker beds (grey arrows show sense of movement) of the oldest sedimentary formation of the Cuddapah basin, the early Proterozoic Gulcheru Quartzites and Vempalle limestones of the Papaghani Group. These lie unconformably on the Archean Peninsular Gneiss which is the fawn colored peneplain in the left part of the DEM. The very distinct dip slopes of the Gani anticline (south of Gani village) are made up of a much younger sedimentary unit, the Banganpalle Quartzites of the Kurnool Group. They were deposited in energetic shallow seas, forming a vast sand shelf, wherein waves and currents winnowed out unstable minerals, leaving behind a nearly pure well sorted and rounded quartz sand. The quartz grains are polycyclic, meaning they show evidence of being derived by weathering of older sandstones, the most likely source being the Gulcheru Quartzites.
Remember this is a Digital Elevation Model, same color means the same altitude range and not mineral composition.
1) Yamuna Left Lateral Fault-
Source: Cartosat 1 DEM National Remote Sensing Center, ISRO
You can see that the Siwalik hills are breached by the Yamuna and dislocated in a left lateral sense, i.e. one would have to turn left to follow the narrow marker rock bed across the fault.
From a previous post on this fault-
Miocene onwards a thick wedge of fluvial sediments filled up a foreland basin that formed in front of rising thrust sheets uplifted along the active Main Boundary Thrust (MBT). That phase ended about 0.5 to 1 mya.
This fluvial wedge over the last half a million years has been deformed into the Siwalik mountains. These mountains form broad synclines and tight anticlines cut by north dipping thrust faults, a result of the continuing compression of the sediment wedge. The southernmost of these thrusts which brings into tectonic contact the anticlinal Frontal Range of the Siwaliks over the alluvial plains in called the Himalayan Frontal Thrust (HFT).
The HFT is broken into segments and the amount of displacement along these segments or thrust blocks is unequal. For example the blocks west of the Yamuna and east of the Ganga have moved southwards with an opposite sense of movement relative to the central block known as the Dun block. To view this, turn on labels and pan southeastwards in embeddable map below until the town of Haridwar where the Ganga enters the plains.
Thus the Yamuna fault has a left lateral sense of movement while the Ganga fault has a right lateral sense of movement. These faults can be thought of as lateral ramps of the HFT accommodating the displacement caused by the southwards movement of the HFT blocks.
Structural considerations indicate that during the last 0.5 my there has been about 8 km of displacement along the Yamuna and Ganga faults, a slip rate of approx. 16 mm year. - See more at: http://suvratk.blogspot.in/2010/12/remotely-india-3-left-lateral-yamuna.html#sthash.H9K4tfrI.dpuf
Miocene onwards a thick wedge of fluvial sediments filled up a foreland basin that formed in front of rising thrust sheets uplifted along the active Main Boundary Thrust (MBT). That phase ended about 0.5 to 1 mya.This fluvial wedge over the last half a million years has been deformed into the Siwalik mountains. These mountains form broad synclines and tight anticlines cut by north dipping thrust faults, a result of the continuing compression of the sediment wedge. The southernmost of these thrusts which brings into tectonic contact the anticlinal Frontal Range of the Siwaliks over the alluvial plains in called the Himalayan Frontal Thrust (HFT).
The HFT is broken into segments and the amount of displacement along these segments or thrust blocks is unequal. For example the blocks west of the Yamuna and east of the Ganga have moved southwards with an opposite sense of movement relative to the central block known as the Dun block. To view this, turn on labels and pan southeastwards in embeddable map below until the town of Haridwar where the Ganga enters the plains.
Thus the Yamuna fault has a left lateral sense of movement while the Ganga fault has a right lateral sense of movement. These faults can be thought of as lateral ramps of the HFT accommodating the displacement caused by the southwards movement of the HFT blocks.
Structural considerations indicate that during the last 0.5 my there has been about 8 km of displacement along the Yamuna and Ganga faults, a slip rate of approx. 16 mm year. - See more at: http://suvratk.blogspot.in/2010/12/remotely-india-3-left-lateral-yamuna.html#sthash.H9K4tfrI.dpuf
This fluvial wedge over the last half a million years has been deformed into the Siwalik mountains. These mountains form broad synclines and tight anticlines cut by north dipping thrust faults, a result of the continuing compression of the sediment wedge. The southernmost of these thrusts which brings into tectonic contact the anticlinal Frontal Range of the Siwaliks over the alluvial plains in called the Himalayan Frontal Thrust (HFT).
The HFT is broken into segments and the amount of displacement along these segments or thrust blocks is unequal. For example the blocks west of the Yamuna and east of the Ganga have moved southwards with an opposite sense of movement relative to the central block known as the Dun block. To view this, turn on labels and pan southeastwards in embeddable map below until the town of Haridwar where the Ganga enters the plains.
Thus the Yamuna fault has a left lateral sense of movement while the Ganga fault has a right lateral sense of movement. These faults can be thought of as lateral ramps of the HFT accommodating the displacement caused by the southwards movement of the HFT blocks.
Structural considerations indicate that during the last 0.5 my there has been about 8 km of displacement along the Yamuna and Ganga faults, a slip rate of approx. 16 mm year.
The Digital Elevation Model also brings out beautifully the Quaternary alluvial fans with tiers of river terraces deposited in the valley between the Siwaliks and the Lesser Himalayas and the intricate drainage on the southern slopes of the Siwalik frontal range.
2) Gani Kalava Fault-
This too has a left lateral movement and has a prolonged history of being reactived during different phases of sedimentation in the Proterozoic Cuddapah Basin of south India. I did my M.Sc dissertation on this area, concentrating on the asymmetric anticline with a gentler dipping southern limb and a nearly vertical dipping northern limb located south of Gani village.
Source: Cartosat 1 DEM, National Remote Sensing Center, ISRO
From a previous post on this fault-
The feature is an ENE plunging asymmetric anticline with spectacular dip slopes of quartz arenites making up the southern limb of the fold and left-lateral movement along a regional fault steepening the northern limb of the fold. There is some copper mineralization along the fault. The Cuddapah basin is an intra-cratonic basin which was filled up in several depositional mega cycles. Sections of two of these mega cycles are exposed in this area. The older mega cycle comprising the Cuddapah subgroup is exposed in the core of the anticline. An angular unconformity separates the older cycle from the younger Kurnool cycle (sub group) which is exposed along the limbs.
Brown arrows shows the offset marker beds (grey arrows show sense of movement) of the oldest sedimentary formation of the Cuddapah basin, the early Proterozoic Gulcheru Quartzites and Vempalle limestones of the Papaghani Group. These lie unconformably on the Archean Peninsular Gneiss which is the fawn colored peneplain in the left part of the DEM. The very distinct dip slopes of the Gani anticline (south of Gani village) are made up of a much younger sedimentary unit, the Banganpalle Quartzites of the Kurnool Group. They were deposited in energetic shallow seas, forming a vast sand shelf, wherein waves and currents winnowed out unstable minerals, leaving behind a nearly pure well sorted and rounded quartz sand. The quartz grains are polycyclic, meaning they show evidence of being derived by weathering of older sandstones, the most likely source being the Gulcheru Quartzites.
Remember this is a Digital Elevation Model, same color means the same altitude range and not mineral composition.
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