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5f the En-3‫ ﺍ‬ncasurenents has been discussed by Bcvan (1983) and Frohlich and
a‫ﺍ‬ncaster (1986), We deid rcpeat thrce of the traverse surveys and found that th

avcrage error of rcpctition is 4.١9%, which is similar to the results obtained by
Bevan (1983), To explore this further, traverses were surveyed solely for the
purposc of carrying out continuous repetition of measurements during different
times of the day. Again, we did not find any repeat errors that had higher values
than about 5%. Oly when the same survey was carried out by different persons,
did higher repeat errors occur; this was found to be caused partly by the slightly
different carrying height between persons, and especially by the different methods
of locating the instrument above a defined measuring point; therefore, all surveys
of any single traverse or single grid were carried out by the same person. A more
detailed study on the equipment's response to different environmental and
climatical conditions and operator errors can be found in Frohlich and Lancaster
(1986).

A total of 19 traverses covering most of the tell area were measured (Figure 1)
including traverses with both two and three parallel lines and with 1 or 2 meters
between measurements. Two of the 19 measured traverses are presented (Figures
3, 4). The traverse labeled MP extends from the center of the mound towards the
eastern border of the tell (Figure 1). It indicates conductivity variation between the
three parallel lines as well as differences between longitudinal areas of the traverse
(Figure 3). It is seen that when two of the three parallel lines indicate similar
conductivity that is different from that of the third parallel line, it may suggest that
inside the area covered by the parallels, differences in the geological anldor
man-made structures may be found, The decrease in the conductivity around 120
meters is caused partly by passing over the eastern fortified wall fbelow the surface)
surrounding the tell and partly by a vertical drop of the surface when reaching the
area adjacent to the tell (Figure 1). The remaining measured traverses yielded
similar patterns, which presumably are a result of the extensive amount of
man-made structures extending from the surface to approximately 6 to 10 meters
below the surface.

25٥ aUALAT AL--BAHRAIN (٨MP)

o‫ﻭ‬ ٥
‫ﺝ‬± ٦٥٥٠
DISTANCE (METERS)
‫ﺃ‬
‫ﺃﻩ‬
‫ ﻱ‬١٥٥٠

‫ﺙ‬
١٥٥,

6‫ﺩ‬

‫ﺝ‬٥ ٥٠‫ﻭ‬

o

‫ﻻ‬

% ‫ﻳﺓﺔ‬ ',‫ﻭ‬ »'‫ ﻡ‬٣‫ﻥ‬ ‫ﺍ‬
٥‫ﻥ‬

Fig. 3, Traverse MP. Length is 130 meters. Three parallel lines are recorded with
measurements for eveyr second meter.

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