The Miocene Baltoro granite forms a massive plutonic unit within the Karakoram batholith, and is composed of comagmatic monzogranites and leucogranites with a mineralogy consisting of quartz-K-feldspar-plagioclase-biotite ± muscovite ± garnet, with accessory sphene, zircon, monazite and opaques. Geochemically the Baltoro granites are mildly peraluminous, and show a calc-alkaline trend on trace-element normalised diagrams with high LIL/HFS element ratios and negative Nb, P and Ti anomalies. REE are strongly fractionated with little or no Eu anomaly. Leucogranites are depleted in most elements compared to monzogranites with notable exceptions being Rb, K and the HREEs. Initial 87Sr/86Sr ratios are 0·7072-0·7128, considerably lower than High Himalayan leucogranites (0·74-0·79), and are indicative of a lower continental crust source. The probable petrogenesis of the Baltoro granite involves dehydration melting of a biotite-rich pelite to produce a voluminous, hot, water-undersaturated magma which could then separate from its source and intrude through an already thickened and still hot crust. Fractional crystallisation of the monzogranites produced the leucogranites and a pegmatite dyke swarm. A suite of lamprophyre dykes including amphibolerich vogesites and biotite-rich minettes intrude the country rock, dominantly to the north, around the Baltoro granite. These calc-alkaline shoshonitic lamprophyres are volatile-rich mantle-derived melts intruded around the same time as the granite, indicating simultaneous melting of the mantle and lower crust beneath the Karakoram during the Miocene, approximately 30 Ma after the India-Asia collision which initially caused the crustal thickening. Intrusion of mantle melts provided heat to promote crustal melting and may have selectively contaminated the granite magma.The Baltoro granite intrudes sillimanite gneisses with melt pods along the southern margin indicating temperatures above 700°C at the time of intrusion. Locally, internal fabrics and numerous aligned xenoliths along the southern margin in the Biafo glacier region indicate steep, southward-directed thrusting during emplacement. Along the northern contact, the Baltoro granite intrudes anchimetamorphic to greenschist facies metasedimentary rocks with an andalusite-bearing contact aureole. Northward-directed culmination collapse normal faulting during Miocene emplacement is inferred, in order to explain the P-T differences either side of the pluton. This also provided an extensional stress regime in the upper crust to accommodate the rising magma.

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Environmental policymakers and regulators are often in the position of having to prioritize their actions across a diverse range of environmental pressures to secure environmental protection and improvements. Information on environmental issues to inform this type of strategic analysis can be disparate; it may be too voluminous or even absent. Data on a range of issues are rarely presented in a common format that allows easy analysis and comparison. Nevertheless, judgments are required on the significance of various environmental pressures and on the inherent uncertainties to inform strategic assessments such as "state of the environment" reports. How can decisionmakers go about this type of strategic and comparative risk analysis? In an attempt to provide practical tools for the analysis of environmental risks at a strategic level, the Environment Agency of England and Wales has conducted a program of developmental research on strategic risk assessment since 1996. The tools developed under this program use the concept of "environmental harm" as a common metric, viewed from technical, social, and economic perspectives, to analyze impacts from a range of environmental pressures. Critical to an informed debate on the relative importance of these perspectives is an understanding and analysis of the various characteristics of harm (spatial and temporal extent, reversibility, latency, etc.) and of the social response to actual or potential environmental harm from a range of hazards. Recent developments in our approach, described herein, allow a presentation of the analysis in a structured fashion so as to better inform risk-management decisions.

The Main Karakoram Thrust (MKT) separates the Karakoram Plate from the accreted Kohistan—Ladakh Terranes and Indian Plate to the south. Within the central Karakoram three geologically distinct zones are recognized: from south to north (i) the Karakoram metamorphic complex, (ii) the Karakoram batholith and (iii) the northern Karakoraih sedimentary terrane. Magmatic episodes of Jurassic and mid-Upper Cretaceous age are recognized before India-Asia collision at ca. 50-45 Ma. Both reveal subduction-related petrographic and geochemical signatures typical of Andean-type settings. Associated with the Jurassic event was a low-pressure metamorphism (Ml). Synchronous with the mid-Upper Cretaceous episode was the passive accretion of the Kohistan-Ladakh terrane to the Karakoram and closure of the Shyok Suture Zone (SSZ). The main collision between the Indian and Asian Plates resulted in crustal thickening beneath the Karakoram and development of Barrovian metamorphism (M2). Early postcollisional plutons dated at 36-34 Ma cross-cut regional syn-metamorphic foliations and constrain a maximum age on peak M2 conditions. Uplift of the Karakoram metamorphic complex in response to continued crustal thickening was synchronous with culmination collapse along the inferred Karakoram Batholith Lineament (KBL). A combination of thermal re-equilibration of thickened continental crust and the proposed addition of an enriched mantle component promoted dehydration, partial melting and generation of the Baltoro Plutonic Unit (BPU). It was subsequently emplaced as a hot, dry magma into an extensional mid-crustal environment. A contact aureole (M3) was imposed on the low-grade sediments along the northern margin, whereas isograds in uplifted metamorphic rocks to the south were thermally domed with in situ migmatization.