Franciscan Complex olistostrome at Crescent City, northern California

Sedimentology ◽  
1989 ◽  
Vol 36 (3) ◽  
pp. 471-495 ◽  
Author(s):  
K. R. AALTO
Geosciences ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 338 ◽  
Author(s):  
Loren A. Raymond

The Franciscan Complex of California is characterized in part by the presence of mélanges. In general, mélange origins are attributed to sedimentary, tectonic, or diapiric processes—or a combination of these. Published reviews list the main features of mélanges characteristic of each type of origin. In this review, particular diagnostic features typical of sedimentary, tectonic, and diapiric mélanges are used to assess 15 specific mélanges, which in some cases have been interpreted in contrasting ways in the literature. The data do not support the view that most Franciscan mélanges were formed by sedimentary processes, but rather that both tectonic and sedimentary processes are important. There is little evidence that diapirism contributed significantly to Franciscan mélange genesis. Tectonic features present in most mélanges of subduction accretionary complexes create challenges in assessing mélange-forming processes. Notably, although tectonic overprints commonly mask the primary diagnostic fabric of sedimentary mélanges, some diagnostic features—such as depositional contacts, fossils in mélange matrix, and interlayering of mélange and non-mélange units—are critical to recognition of mélanges of sedimentary origin.


2014 ◽  
Vol 2014 (1) ◽  
pp. 1019-1028
Author(s):  
Renee V. McKinnon ◽  
Agustus J. Bannan

ABSTRACT On March 11, 2011, Japan was struck by a powerful earthquake that resulted in tsunami damage. In addition to the destruction within Japan, several ports in northern California were also affected. Two harbors in California suffered major vessel and infrastructure casualties which resulted in large amounts of oil and hazardous substances in the water from various sources. The agencies responding to these harbors found themselves with several challenges: (1) assessing and responding to a rare and enormous event that had the potential to effect the entire west coast; (2) organizing the tactical operations and logistical support for the two most effected locations which were 430-miles apart; and (3) assessing and mitigating unknown safety hazards in the water and then determining an appropriate funding source. Damage reports from various cities, including Richmond, Fort Bragg and Crescent City, followed over the next few hours. Response teams deployed to mitigate the greatest threats, though some of threats weren't immediately obvious. The response became a two-branch operation, focused on Santa Cruz and Crescent City, each with distinctive problems and separated by a difficult distance, with a central Incident Command Post (ICP) directing the response. The pollution potential and economic significance was far greater in the northern city, leading the Federal On-Scene Coordinator (FOSC) to create an Area Command. This eventually evolved into a single remote ICP. While only considered a type-3 event, Federal On-Scene Coordinator Representatives (FOSCRs) were strained to their limits on Advanced ICS knowledge, financial management, and interagency salvage. In this event, the Coast Guard struggled with, but succeeded in dealing with, a catastrophe that no one on the West Coast had dealt with in almost 50 years.


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