12, 1973, and collected data for the Nazca Plate Project until 

 its return on June 11, 1973. 



Other activities during the past year included: distribution 

 of data from the 1972 HIG-OSU cruises; analysis of the 1972 

 data after integration with previously existing data in the re- 

 gion; preparation of publications and presentations of interpre- 

 tations involving the data; meetings to plan the 1973 HIG-POL 

 cruises; and post-1973-cruise meetings to organize the process- 

 ing and analysis of the data. 



Approximately 52,630 nautical miles of geophysical data 

 were received last year by NOAA Environmental Data Ser- 

 vice's National Geophysical and Solar-Terrestrial Data Center, 

 including bathymetric, magnetic, gravity, seismic, 3.5-kHz echo 

 sounder, and sonobuoy data. 



Mid-Atlantic Ridge 



Better understanding of the geological processes operating 

 along mid-ocean ridges is the basis of a study of the Mid- 

 Atlantic Ridge. Particular attention is given to the forces which 

 drive the two flanks of the ridge apart and bring new crustal 

 material to the surface. These processes are also believed to 

 concentrate heavy metals. The heavy metal concentrations, 

 when brought above sea level through the processes of plate 

 tectonics, become major ecnomic resources. 



Following the recommendations of the Princeton Work- 

 shop (January 1972), IDOE is supporting several studies along 

 the Mid-Atlantic Ridge. Dr. Hermance (Brown University), in 

 cooperating with the National Energy Council of Iceland, is 

 investigating the deep crustal processes in the upper mantle 

 and lower crust which generate high heat flow at the surface. A 

 second group from Lamont, cooperating with Dalhousie (Nova 

 Scotia), drilled a 3,000-foot hole on the Island of San Miguel, 

 Azores. The original goal of 5,000 feet was abandoned when 

 high temperatures and pressures forced drilling operations to 

 stop. Samples from this well, including water and rocks, are 

 being analyzed for their hydrothermal minerals. A third pro- 

 ject is working near the intersection of the Mid-Atlantic Ridge 

 and the Romanche Fracture Zone. Samples have been collected 

 at depths of several thousand meters, in order to understand 

 the processes by which the lower crust is differentiated from the 

 upper mantle. The major effort, however, has been Project 

 FAMOUS (French American Mid-Ocean Undersea Study). 

 United States and French scientists conducted an intensive in- 

 vestigation along the ridge near the Azores to determine the 

 most "active" area. These site surveys during 1972 and 1973 

 used a variety of research tools, including side-scan radar for 

 high-resolution bathymetry, NRL's LIBEC (from which photo 

 mosaics of the seafloor were prepared), heat-flow measure- 

 ments, ocean-bottom seismometers, and extensive magnetom- 

 eter exploration. The surveys culminated in a series of dives 

 during June, July, and August 1974, using manned submersibles 

 — the French Archimede and Cyana and the U.S. Alvin. 

 Teams of U.S. and French scientists have been making detailed 

 observations along valley walls, collecting samples, and taking 

 photographs. Aboard the RV Knorr research scientists are 

 analyzing samples for metal content — to guide subsequent dives 

 to the most promising locations. Hydrothermal vents are be- 

 lieved to have been observed, but their existence has not been 

 confirmed. 



As part of the FAMOUS investigation, and at a distance 

 of 20 miles from the FAMOUS dive sites, the Glomar Chal- 



lenger drilled 1,900 feet into the volcanic rock of the ocean 

 bottom. Suites of samples from the Azores Deep Hole, 

 FAMOUS dives, and Deep Sea Drilling Project will be studied 

 as part of a comprehensive project. 



Metallogenesis, Hydrocarbons, and Tectonic Patterns 

 in Eastern Asia 



The Workshop on Metallogenesis and Tectonic Patterns 

 in East and Southeast Asia — a program of research organized 

 as part of the International Decade of Ocean Exploration 

 (IDOE)— was held September 22-29, 1973, in Bangkok, 

 Thailand, under the sponsorship of the Committee for Co- 

 ordination of Joint Prospecting for Mineral Resources in Asian 

 Offshore Areas (CCOP) and the Intergovernmental Oceano- 

 graphic Commission (IOC). The original proposal for this 

 program of research contained the following main objectives: 



1. To determine the location, characteristics, and 

 significance of the principal tectonic features of 

 the continental margins and associated structural 

 elements of east and southeast Asia; 



2. To relate metalliferous ore deposits to the major 

 tectonic features and plate boundaries, particu- 

 larly convergence and shear boundaries; and 



3. To analyze the characteristics of various types of 

 sedimentary basins and their hydrocarbon habitat 

 in terms of their position relative to plate margins 

 and tectonic features, and to study the geological, 

 geochemical, and geothermal history factors gov- 

 erning the transformation of organic matter into 

 hydrocarbons in small ocean basins. 



The east Asian region is considered, by present theories, 

 to be an area where gigantic lithospheric plates interact. It offers 

 a unique opportunity for geological and geophysical investi- 

 gation of regional tectonics within a relatively small area of the 

 globe where all the important processes of plate-boundary 

 tectonics can be examined in a region where there is a gap 

 in presently organized programs of marine geological and 

 geophysical investigations, but where exploration for mineral 

 resources is increasing. The region is rapidly changing from 

 one of the least explored to one of the most extensively investi- 

 gated parts of the worid. The IDOE Workshop had as its main 

 focus the need to develop a strategy and program for effec- 

 tive and efficient use of scientific resources in the exploration 

 and investigation of this region. 



Basic problems pertinent to undersjanding the geology 

 and mineral distribution in the east Asia region were sum- 

 marized at the beginning of the Workshop as follows: 



1. What is the relationship between the process of min- 

 eralization and (a) zones of subduction where both oceanic 

 and continental sides are involved in the deformation, (b) 

 areas of high heat flow such as interarc and foreland basins, 

 and (c) small spreading centers within major plates? 



2. How does southeast Asia fit into the pattern of con- 

 tinental drift? Many authors who have dealt with the region's 

 past relationships tended to try to fit southeast Asia into 

 Gondwanaland, in spite of much contrary evidence. Some 

 marine geophysicists favor the idea of relating parts of south- 

 east Asia, such as the island of Borneo, to mainland China. 

 Others do not put southeast Asia into the Gondwanaland portion 

 of Pangaea, but leave a narrow gap of ocean, whereas a re- 



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