Schedule

Friday, 11 April, 2008
11:00 Registration and Lunch Located at the UCSC Arboretum
12:00 Welcome and Introductory Remarks Organizing committee
12:10 Inside Fault Processes Kohtaro Ujiie: Frictional melting and fluidization recorded ancient accretionary complexes and their implications for dynamic weakness of faults during subduction earthquakes

Akito Tsutsumi: High-velocity frictional properties of rocks

Harold Tobin: Drilling the Megathrust: NanTroSEIZE Initial Results and Future Plans

David Kirschner: The Agony and Ecstasy of the SAFOD drilling project
14:10 Refreshments  
14:25 Fluids and Deformation Kevin Brown: New insights into earthquake processes: Field and experimental observations

Dan Orange: Seep science and tectonic hydrogeology applied to oil and gas exploration in Indonesia's frontier basins

Rick Sibson:Compressional inversion in the seismogenic crust of Honshu, Japan - the case for fluid-driven faulting

Demian Saffer:
17:30 Poster Presentations with Refreshments  
Saturday 12 April, 2008
08:00 Continental Breakfast Located at the UCSC Arboretum
08:30 Linking Structure and Process

Greg Moore: Partitioning of slip between the decollement and splay faults in the NanTroSEIZE transect

Sarah Roeske: Effects of triple junction(s?) on the Late Cretaceous-Early Cenozoic northern Cordillera margin

Gaku Kimura: Geology of a seismogenic splay fault

Tim Byrne: From Accretion to Exhumation
10:15 Refreshments
10:30 Time & Space Tim Dixon: Subduction zone geodesy: Some new insights relating short and long term deformation

Kelin Wang: Thermal models of subduction zones

Mike Underwood: Sedimentary evolution of subduction margins

Peter Vrolijk: A Santa Cruz perspective on faults and fluids and the pursuit of oil and gas

12:15
FIELD TRIP:
A Visit to Coastal Melange Exposures in the Classic Franciscan Complex of Linda Mar (Pacifica), California
led by Dr. John Wakabayashi, CSU Fresno
17:30
BBQ and Entertainment


Field Trip: A Visit to Coastal Melange Exposures in the Classic Franciscan Complex of Linda Mar (Pacifica), California

John Wakabayashi, CSU Fresno

Overview

We will visit good sea cliff exposures of Franciscan Complex melange at Linda Mar (Pacifica), a few kilometers south of San Francisco. Many consider the Francsican Complex the world's type subduction complex. It certainly records an extended record of subduction, having formed over the course of over 140 million years of continuous subduction. The Franciscan consists primarily of offscraped and underplated trench sediments, now sandstones and shales, with a smaller amount of volcanic and pelagic sedimentary rocks. The clastic sedimentary rocks were deposited shortly before incorporation into the accretionary complex, whereas the pelagic sediments and most of the volcanic rocks were far-traveled passengers on the down-going plate.

The Franciscan consists of both coherent units and block-in-matrix melanges, with the proportion between the two varying spatially. The coherent terranes are nappes up to several kilometers thick and are separated from each other by low-angle melange zones that an also reach several kilometers in thickness. The coherent terranes themselves are internally imbricated, and the individual thrust faults between imbricates range from a few centimeters in thickness to melange zones hundreds of meters thick.

The exposure at Pacifica is an example of an intra-terrane melange zone within the Permanente terrane of the Franciscan. The Permanente terrane consists of a significant amount of basalt, with clastic rocks, limestone and chert. The shear zone we will visit is structurally low within the Permanente terrane, and consists of a sheared shale matrix with blocks of sandstone, metabasalt, and very rare amphibolite/blueschist. Incipient growth of blueschist facies minerals has been reported from the coherent basalts, but prehnite-pumpellyite facies metamorphism is more commonly observed. Much of the deformation we observe in the outcrop probably occurred at a depth of over 15 kilometers in the subduction complex.

The hour + drive north to the field site includes breathtaking views of the Pacific Ocean, passing through protected coastal agricultural trust land as well as areas of native coastal chaperal vegetation.