Tectonics of Calabria, Southern Italy

Calabria, the toe of Italy, preserves a unique record of Hercynian, Tethyan, and Alpine tectonics. My group works on several aspects of this deformation.

In the aftermath of the Hercynian Orogeny--the European equivalent to the Alleghenian Orogeny--a large amount of post-orogenic magmatism affected the rock record. Several hypotheses have been presented, including post-orogenic collapse, lithospheric delamination, and strike-slip faulting. Our group is working on understanding what tectonic process may have occurred and whether the upper mantle and lower crust section exposed in Calabria may contain unique evidence of this process.

Current and previous research projects:

Unlike classic Penrose-type ophiolitic sequences, ophiolite fragments accreted in the Apennines and Alps appear to represent pieces of Tethyan hyperextended margins. These can be recognized in the field by exposures of volcanic and oceanic sedimentary sequences that are separated from high-temperature gabbroic mylonites and serpentinite by low-angle detachment faults. These zones may also be locations prone to subduction initiation beneath continental margins. My group uses field mapping, geochemistry, and geochronology to understand the history of these unusual pieces of crust.

Current and previous research projects:

Claire Battistella (BS 2015; MS Univ of Alabama; now at Golder), Geologic mapping of a Tethyan ocean-continent transition detachment fault exposed in the Liguride Complex of Southern Italy

The transition between Tethyan rifting and Alpine/Apenninic convergence requires the development of a subduction zone beneath the European margin. When and how this subduction zone initiates is an open question in Western Mediterranean tectonics. Furthermore, the effects of subduction initiation on the regional geology are poorly understood. We have used field mapping, geochronology, and modeling to understand these processes.

Current and previous research projects:

Will Schmidt (BS 2014, now at USC, PhD), A reassessment of fission-track ages and the thermal evolution of the Calabrian Arc after the initiation of subduction, Southern Italy



Early history of the Trinity Terrane, Klamath Mountains, California

The Trinity Terrane of Northern California is an unusual crustal unit containing both Ordovician blueschist-facies rocks and Neoproterozoic granitoids. We've recently been working out a low-angle detachment fault that may have developed in a ridge setting, or in an island arc. Our group is using field mapping, geochemistry, and geochronology to help understand this strange piece of crust.

Current and previous research projects:

David Hart (MS in progress), New geologic mapping of the Precambrian tonalite associated with the Ordovician Trinity Ophiolite, Klamath Mountains, California

Bret Sample (BS 2016; MS CSU Northridge; now at Arcadis), Is a Triassic subduction initiation event recorded in the Fort Jones Terrane, Klamath Mountains, California?

Emily Haugen (BS 2015; MS Utah State 2017; now at USGS), Age and origin of leucocratic rocks of the Neoproterozoic Trinity Ophiolite, Klamath Mountain, California

Anthony Billecci (BS 2014, now at ERM), Detailed mapping and observations of a new section of the Skookum Gulch Schist and Trinity Ophiolite, Eastern Klamath Mountains, California

Jesse Stovall, undergraduate, (BS 2013, now at the Army Corps of Engineers), Possible counterclockwise P-T-t path from the Fort Jones Terrane near Yreka, California

Tectonics of the San Andreas Fault Zone, California

The San Andreas Fault System has transported fragments of the Southern Sierra Nevada northward. My group works on 1) reconstructing these fragments back to their original location in the Southern Sierra Nevada and 2) inversion of Monterey Formation basins caused by stepover migration.

Current and previous research projects:

Robin Hankins (BS in progress), Geobarometry of granitoids and U-Pb detrital zircon geochronology of overlying sedimentary cover in the Northern Salinian Block, California