where available, by 1°C contours. Geographic accuracy is that of Loran-A. 

 Strip charts, flight charts, logs, and other original material are being 

 archived by NOAA's Environmental Data Service. 



Three conclusions are evident from the oil slick maps. First, the oil 

 distribution was primarily influenced by the clockwise rotary tidal currents 

 and the local winds up until December 21, 1976 as evidenced by the hook 

 pattern on maps IV-1 to IV-5 in Appendix IV. Second, the movement of the oil 

 was offshore to the east-southeast. The speed of the oil was approximately 

 1.6 knots on December 20-21, and 1.4 knots on December 21-22 under the influ- 

 ence of mean west winds of 30 knots. Third, the oil was not observed north 

 of 41° 21' (map IV-5 in Appendix IV) northwest of 70° 10' (map IV-17 in 

 Appendix IV). Furthermore, the slick was not observed closer than 15 miles 

 off shore of Nantucket (map IV-17 in Appendix IV) . 



2.2.2 Physical Observations 



During the course of the oil spill visual and photographic observations 

 were made of the behavior of the No. 6 fuel in cold water. These observa- 

 tions were made to answer the following questions: 



1. What is the life cycle of oil pancakes? 



2. How does the oil pick up motion from wind or waves? 



3. What are the dynamics of the underside of oil slicks? 



4. How does oil get accommodated into the water column? 



Few immediate answers were found to these questions, although more data 

 than ever before was collected. Over the next few months, these data will be 

 more carefully analyzed to provide a better understanding of oil behavior in 

 cold water. The data and findings to date are described below. 



The SOR Team collected more than 800 photographs during the period 

 covered by this report. A selected group has been included in Appendix III. 

 These photographs show (1) the history of the oil discharge from the Argo 

 Merchant (Photographs 1 to 16); (2) details of oil distribution and pancake 

 formation and life cycle (Photographs 17 to 28 and 37 to 42) ; (3) details of 

 oil behavior and bottom side morphology (Photographs 29 to 32) ; (4) tech- 

 niques of measuring water and differential oil/water velocities (Photographs 

 33 to 36); (5) burn tests (Photographs 42 to 44), oil sampling (Photographs 

 45 and 46) , and local fauna (Photographs 47 and 48) . Aerial photographs were 

 taken to calibrate visual estimates of the areal extent of pancakes and sheen 

 in oiled areas. Vertical aerial photography was obtained on NASA, AMSI, and 

 EPA overflights. Of particular interest in describing the behavior of the 

 oil are the NASA flights on December 19 and 22. 



The NASA overflight on December 19 yielded 202 infrared 9" x 9" color 

 photographs along the flight track shown in Figure 2-1. Twelve legs were 

 flown over a period of 1 hour and 52 minutes (Table VII-1) . Five frames were 

 selected and printed to show typical results (Photographs 17 through 21, 



20 



