Buddington (1959) pointed out that the construction of large crustal magma chambers involves complex internal processes as well as multiple country rock material transfer processes (MTPs), which reflect large horizontal, vertical and temporal gradients in physical conditions. Thus, we have attempted to determine the relative importance of different magmatic and country rock MTPs at various crustal depths, and whether country rock MTPs largely transport material vertically or horizontally, rather than seeking a single model of magma ascent and emplacement.Partially preserved roofs of nine plutons and in some cases roof-wall transitions with roof emplacement depths of 1-5-11 km were mapped. During emplacement, these roofs were not deformed in a ductile manner, detached or extended by faults, or significantly uplifted. Instead, sharp, irregular, discordant contacts are the rule with sloped blocks often preserved immediately below the roof, even at depths of 10 km. The upper portions of these magma chambers are varied, sometimes preserving the crests of more evolved magmas or local zones of volatile-rich phases and complex zones of dyking and magma mingling. Magmatic structures near roofs display a wide variety of patterns and generally formed after emplacement. Transitions from gently dipping roofs to steep walls are abrupt. At shallow crustal levels, steep wall contacts have sharp, discordant, stepped patterns with locally preserved sloped blocks indicating that the chamber grew sideways in part by sloping. Around deeper plulons, an abrupl transition (sometimes within hundreds of metres) occurs in the counlry rock from discordanl, brittle roofs to moderately concordanl, walls deformed in a ductile manner defining narrow structural aureoles. Brittle or ductile faults are not present at roof-wall joins.Near steep wall contacts at shallow to mid-crustal deplhs (5-15 km), vertical and horizonlal deflections of pre-emplacement markers (e.g. bedding, faults, dykes), and ductile slrains in narrow aureoles (0-1-0-3 body radii) give a complele range of bulk strain values lhal account for 0-100% of the needed space, but average around 30%, or less, particularly for larger balholilhs. A lack of far-field deflection of these same markers rules out significant horizontal displacement outside Ihe aureoles and requires lhat any near-field lateral shorlening is accommodaled by vertical flow. Lateral variations from ductile (inner aureole) to brittle (outer aureole) MTPs are lypically observed. Compositional zoning is widespread wilhin Ihese magma bodies and is Ihoughl lo represent separately evolved pulses lhal Iravelled up the same magma plumbing system. Magmatic foliations and linealions commonly cross-cut conlacts belween pulses and reflecl the slrain caused eilher by Ihe late flow of melt or regional deformation.Country rocks near the few examined mid-to deep crustal walls (10-30 km) are extensively deformed, with both discordant and concordant contacts present; however, the distinction between regional and emplacement-relate...
