Geochemical and geochronological analyses provide quantitative evidence about the origin, development and motion along ductile faults, where kinematic structures have been overprinted. The Main Central Thrust is a key structure in the Himalaya that accommodated substantial amounts of the India-Asia convergence. This structure juxtaposes two isotopically distinct rock packages across a zone of ductile deformation. Structural analysis, whole-rock Nd isotopes, and u-Pb zircon geochronology reveal that the hanging wall is characterized by detrital zircon peaks at c.

In the Indian Himalaya, a 15 km stretch of the North Sikkim Highway that is exceptionally susceptible to landsliding is characterized by fine-grained, low permeability debris material. Lanta Khola is one of the major debris slides in this stretch and is active every year during the monsoons. Although the relationship between rainfall and landsliding in the area is obvious, there is no previous study of precipitation thresholds for landslide initiation. Review of available rainfall and landslide activity data for the area between 1998 and 2006 suggests that sliding cannot be modeled by typical exponential relationships between cumulative rainfall (E) and rainfall duration (D). An alternative rainfall threshold has been proposed that predicts sliding if normalized cumulative rainfall for more than 15 days exceeds 250 mm. It is suggested that when this cumulative rainfall threshold is exceeded, the debris zone in the affected stretch becomes saturated and fails, causing landsliding.

On the island of Sikinos in the Cyclades a schistose carapace separates a marble-blueschist cover sequence from underlying basement rocks. The basement 'core', comprising metapelitic gneisses, biotite-bearing granodiorites and aplites, becomes increasingly strained towards the carapace with progressive obliteration of earlier structures and intensification of a mylonitic foliation that becomes pervasive within the carapace. Granodiorites in the 'core' can be traced into microcline schists within the carapace, whereas metapelitic gneisses are converted to garnet-mica schists. The carapace is therefore a simple shear zone comprising basement rocks mylonitized during overthrusting of the cover. The basement is exposed on the islands of Naxos, Ios and Sikinos ( Van der Maar 1980,1981

At Deobhog, migmatitic gneisses and granulites of the Eastern Ghats Belt are juxtaposed against a cratonic ensemble of banded augen gneiss, amphibolite and calcsilicate gneiss, intruded by late hornblende granite and dolerite. In the migmatitic gneiss unit, early isoclinal folds (syn‐D1M and D2M) are reoriented along N–S‐trending and E‐dipping shear planes (S3M), with (S1M–S3M) intersection lineations having steep to moderate plunges. The near‐peak P–T  condition was syn‐D3M (≥900 °C, 9.5 kbar), as inferred from syn‐D3M Grt+Opx‐bearing leucosomes in mafic granulites, and from thermobarometry on Grt (corona)–Opx/Cpx–Pl–Qtz assemblages. The P–T  values are consistent with the occurrence of Opx–Spr–Crd assemblages in spatially associated high‐Mg–Al pelites. A subsequent period of cooling followed by isothermal decompression (800–850 °C, c. 7 kbar) is documented by the formation of coronal garnet and its decomposition to Opx+Pl symplectites in mafic granulites. Hydrous fluid infiltration accompanying the retrograde changes is manifested in biotite replacing Opx in some lithologies. The cratonic banded gneiss–granite unit also documents two phases of isoclinal folding (D1B & D2B), with the L2B lineation girdle different from the lineation spread in the migmatitic gneiss unit. Calcsilicate gneiss (Hbl–Pl–Cpx–Scap–Cal) and amphibolite (Hbl–Pl±Grt±Cpx) within banded gneisses record syn‐D2B peak metamorphic conditions (c. 700 °C, 6.5 kbar), followed by cooling (to c. 500 °C) manifested in the stabilization of coronal clinozoisite–epidote. The D3B shear deformation post‐dates granite and dolerite intrusions and is characterized by top‐to‐the‐west movement along N–S‐trending, E‐dipping shear planes. Deformation mechanisms of quartz and feldspar in granites and banded gneisses and amphibole–plagioclase thermometry within shear bands in dolerites document an inverted syn‐D3B thermal gradient with temperature increasing from 350 to 550 °C in the west to ≥700 °C near the contact with the migmatitic gneiss unit. The thermal gradient is reflected in the stabilization of chlorite after hornblende in S3B shears to the west, and post‐D2B neosome segregation along D3B folds and shears to the east. The contrasting lithologies, early structures and peak metamorphic conditions in the two units indicate unconnected pre‐D3P–T –deformation histories. The shared D3 deformation in the two units, the syn‐D3 inverted thermal gradient preserved in the footwall cratonic rocks and the complementary cooling and hydration of the hanging wall granulites across the contact are attributed to westward thrusting of ‘hot’ Eastern Ghats granulites on ‘cool’ cratonic crust. It is suggested that the Eastern Ghats migmatitic gneiss unit is not a reworked part of the craton, but a para‐autochthonous/allochthonous unit emplaced on and amalgamated to the craton.

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