The Wooley Creek batholith and Slinkard pluton are adjacent plutons with identical U-Pb zircon ages of 161 +4/-2 Ma. The plutons dip toward each other, which suggests that they are connected in the subsurface. Geologic and thermochemical evidence shows that the Slinkard pluton is the structurally lowest part of the system and the Wooley Creek batholith the structurally highest, with a total str...

We have developed a new quantitative method to estimate paleohorizontal in granitic plutons using the aluminum-in-hornblende (AH) barometer. The method is used to correct previously published paleomagnetic data from the 93–96 Ma Mount Stuart batholith of the Cascades Mountains, Washington State, for the effects of postemplacement tilting. AH barometry was done on 46 samples from the batholith u...

Major systems of northwesterly, northerly, and northeasterly trending recurrilig fractures or faults controlled emplacement of various units of the Iron Mask batholith. The batholith was emplaced in a high level volcanic to subvolcanic environment, comagmatic with Nicola volcanic rocks and coeval with part of the upper Nicola succession. The batholith intruded volcanic and sedimentary rocks of ...

The calc-alkaline Ladakh batholith (NW Himalayas) was dated to constrain the timing of continental collision and subsequent deformation. Batholith growth ended when collision disrupted subduction of the Tethyan oceanic lithosphere, and thus the youngest magmatic pulse indirectly dates the collision. Both U-Pb ages on zircons from three samples of the Ladakh batholith and K-Ar from one subvolcan...

Biotite and K-feldspar Ar/Ar systems from the east-central Peninsular Ranges batholith near 33°N were affected by two distinct phases of Late Cretaceous rapid cooling. The 85-Ma biotite K-Ar isochron separates comparatively shallow rocks in the southwest that record earlier cooling (91–86 Ma) from deeper rocks in the northeast that record later cooling (78–68 Ma). Samples close to 85 Ma isochro...

Paleocene plutons on Kodiak Island, in Alaska, contain host-rock xenoliths that have undergone varying degrees of fragmentation, metamorphism and assimilation in the surrounding granitoid rocks, and therefore provide an excellent natural laboratory to study the processes of xenolith fragmentation and magma contamination. Kodiak Island has two belts of Paleocene plutons: the Kodiak batholith tha...

[1] Two fore‐arc magmatic belts exist in Kodiak Island, the granitic Kodiak batholith and the basaltic trenchward belt. Both are part of the 2100 km long Sanak‐Baranof belt, interpreted to result from trench‐ridge‐trench (T‐R‐T) triple‐junction migration. In this hypothesis, trenchward belt basaltic rocks formed as the spreading ridge first entered the accretionary prism, and the larger Kodiak ...

The Iron Mask batholith is an Early Jurassic composite alkaline intrusion located southwest of Kamloops in southcentral British Columbia (Figure 2-6-l). It lies in the southern portion of the Quesnel trough in the lntermontane tcctonic belt. It is a northwest-trending body approximately 22 kilomctres long and 5 kilometres wide intruding volcanic and sedimentary rocks of the eastern belt of the ...

Detrital zircon U-Pb ages for 30 Late Jurassic and Cretaceous sandstones from the Eastern Province of eastern New Zealand, combined with previously-published geochronological and palaeontological data, constrain the time of deposition in the Pahau and Waioeka terranes of the Cretaceous accretionary margin of Zealandia, and their adjacent cover strata. The zircon age patterns also constrain poss...

Cretaceous plutonic rocks of the southern Sierra Nevada batholith between latitudes 35.5°N and 36°N lie in a strategic position that physically links shallow, subvolcanic levels of the batholith to lower-crustal (~35 km deep) batholithic rocks. This region preserves an oblique crustal section through the southern Sierra Nevada batholith. Prior studies have produced large U/Pb zircon data sets f...