Preface
Any major new research initiative requires a period of intellectual gestation during which the community gathers and assimilates a list of major scientific questions to be addressed, the most practical ways to approach the issues and the technical and fiscal resources needed to make a meaningful impact. The U.S. MARGINS Program was no exception. It took the geosciences community a decade of workshops and planning sessions to achieve this goal. The MARGINS community recognized early that a relatively small range of physical and chemical processes (e.g., lithospheric deformation, magmatism, other mass/energy fluxes, sedimentation and fluid flow) were fundamental to the evolution of all margins. Studying these processes wherever they were best expressed and extant today would therefore provide a logical and most expedient line of inquiry for understanding the complex nature of continental margins. The process-oriented and holistic approach to understanding the entire system of margin evolution also meant that broadly based interdisciplinary studies would have to be undertaken and a new class of major experiments would have to be designed to achieve these goals. National Science Foundation’s MARGINS Program, first initiated in 1998, has the explicit goal of elevating the current, largely descriptive, view of the ocean margins to a level where theory, modeling, field observation and experiment can yield a more systemic understanding of processes that control continental margin creation and evolution. The essential amphibious nature of almost all MARGINS’ studies also lends itself ideally for support from both the Division of Earth Sciences and the Division of Ocean Sciences.

The publication of the updated MARGINS Science Plan in the fifth year of funding represents an important milestone for the Program. The individual science plans for four MARGINS initiatives (Rupture of Continental Lithosphere, Seismogenic Zone, Subduction Factory, and Source to Sink) represent the results of the often long and lively discussions within each sub-community of MARGINS. They summarize the current thinking about the major scientific issues and define the state-of-the-science in each initiative as well as outline the progress made so far. This document will serve an important purpose as a planning document within NSF and will be used for reviews of the Program and for budgetary purposes. Major programs have to be continuously appraised and their future growth justified at several levels – this document will form the basis of such activity for the MARGINS Program. But more importantly, it is hoped that the document will serve the community as a focal point for proposing future research and new experiments in each area.
Over the past five years the Program has clearly seen an accelerating interest in MARGINS and MARGINS-related research. Five years of MARGINS funding, and through its sponsored workshops and symposia and synergistic development of MARGINS-type programs in other countries, a generation of geoscientists have been trained and grown accustomed to think holistically about the entire system, beyond their own disciplines. This alone is bound to positively influence all future continental margin research in allowing investigators to think broadly and propose bold new experiments. The Program has already seen an improvement in the quality of experiments proposed to study areas outside the MARGINS “focus sites” with this holistic approach. MARGINS research and planning is also providing some of the basic studies and arguments for drilling along the ocean margins in the new Integrated Ocean Drilling Program.

Many active scientists and champions for individual initiatives have worked hard to produce this document. They received valuable guidance from the MARGINS Steering Committee, many of whose members volunteered or were conscripted into producing the initial drafts of the science plans based on the various workshops and symposia. Others from the community at large were sometime called upon to help out at short notice. All did so cheerfully. The MARGINS Office worked tirelessly to produce the final document. NSF acknowledges their hard work in producing this important revision of the Science Plan for the benefit of the entire Earth Science community.

Bilal Haq
For NSF MARGINS Program