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the acting forces, rates of activity, interactions of forces and sediments, and 

 variations in activity over time. If the field work will involve extensive data 

 collection, a preliminary site visit is highly recommended in order to help 

 determine sampling considerations and to develop a sampling plan. 



Spatial and temporal aspects of site inspection are important considerations. 

 The spatial dimensions of the sampling plan should have adequate longshore 

 and cross-shore extent, and an adequate grid or sample spacing with which to 

 meet study objectives. Temporal considerations include the frequency of 

 sampling and the duration over which samples will be collected. Sampling 

 frequency and duration are most important in modern process studies, such as 

 monitoring the topographic and bathymetric changes associated with storms. 

 Studies of paleoenvironmental or geologic time scales usually do not require 

 repetitive visits, but thorough spatial sampling is critical. 



Information collected from the field observation and measurements can be 

 used in analysis and numerical models. A conceptual model is often 

 formulated while the initial observations are being conducted. The conceptual 

 model is in essence a perception or understanding of the situation. The 

 perception may be validated by the application of empirical relationships. 

 Further verification of the observed field relationships is obtained by the 

 application of physical or mathematical laws. The quantifying of parameters 

 and the use of these parameters in testing the physical or mathematical 

 relationships may support or negate the interpretation. Additional 

 observations may be required to test a wider variety of conditions, and 

 conceptual models may need to be revised depending on the results of the 

 study. 



Site Inspection and Local Resources 



A general site inspection can provide insights toward identifying significant 

 research problems at a study area, in verifying and enhancing data from aerial 

 photographs and remote sensing sources, and in developing sampling 

 strategies for more rigorous types of field work. Even for a brief site visit, 

 thorough preparation is strongly recommended. Preparation should include 

 reviewing the pertinent geologic, oceanographic, and engineering literature, 

 compiling maps and photographs, and understanding the scope of the problem 

 or situation. If one individual cannot achieve all these objectives, it is 

 necessary that a team conduct the preliminary project planning. The field 

 inspection should include observations by all members if at all possible. 



The duration of the field examination must be sufficient to assess the major 

 objectives of the study. Local residents, existing data records, and field moni- 

 toring equipment may need to be used. A site inspection should include 

 observation of marine forces and processes, assessment of geomorphic 

 indicators, visits to neighboring sites, and interviews with residents and other 



Chapter 3 Field Data Collection and Observation 



