Research

The causes and consequences of flat slab volcanism have long been a topic of geologic interest. Subduction beneath modern-day Colombia provides an active natural laboratory on the subject, as the down-going Nazca plate is thought to be torn, leading to flat-slab subduction north of the Caldas tear and classic, steeply dipping subduction in the south. However, little is known about the timing of this likely tear and its effects on the regional geology and volcanic history of Colombia. We investigate a series of volcanic domes erupted on either side of the Caldas tear to interrogate the tectonic and magmatic processes that led to their formation. 

The Whakamaru eruptions are the largest known eruptions in the modern Taupō Volcanic Zone in Aotearoa New Zealand. The complex field relationships of the ignimbrites have thus far obscured the timing of their eruption(s). We use corroborating evidence from the ignimbrite record and associated fall deposits to determine how many magma bodies fed the Whakamaru eruptions and how they erupted through time. Not only are there multiple magma bodies that fed the Whakamaru eruptions, but we find there are two distinct magmatic subsystems that coexisted and led to the eruption of different magma types at the same time.

The style of eruption is difficult to determine in the Paraná large igneous province in southern Brazil. They include both effusive and explosive units, exposed at the plateau and in ~400-800 m canyon walls. We focus on the canyons, where the continuous exposures provide unparalleled access to vertically stacked packages. Using physical volcanology from the large (10s km) to small (mm) scale, we characterize the different eruption styles. This work begins to resolve the distribution of eruptive vents, and the waxing and waning of these volcanic centers through time. The connections between canyons may ultimately unlock the volcanism associated with SLIP and continental break-up processes.

Identifying where eruptible magma bodies form and are stored in the crust is critical for understanding magma transport, eruption hazards, and magma body longevity. During the recent Krafla IDDP-1 drilling project, magma was surprisingly intersected at 2.1 km depth. Here, we ground truth the use of rhyolite-MELTS geobarometry for very low pressures using natural Krafla IDDP-1 compositions.  We shed light on previously under-reported magma bodies stored at the shallowest crustal depths (defined here as < 4 km) prior to eruption, and on a new approach to identify their existence beneath modern and ancient volcanic centers.