An Unexplored Realm in the Heartland of the Southern Gulf ... - Famsi

Figure 3.3. Aerial photo of El Marquesillo in 1991. River flow is
from bottom to top of the photo, site is outlined in red (INEGI 1991).
In 1994, major changes in the river’s course began to occur. Figure 3.4 shows the
initial change of the channel in 1994. Flooding caused the channel to flow over the low
banks and onto the plain at the narrow neck of the southern (lower) meander, effectively
eliminating the loop from the river’s flow, and creating a new channel. Figure 3.5
illustrates the same phenomena occurring to the northern meander that residents report
occurred in 1998. Today, these bypassed loops have become isolated bodies of standing
water called oxbow lakes. The cessation of the river channel into the southern loop or
meander followed higher than normal flooding in 1994, and the closing of the northern
loop occurred after monumental flooding in 1998. Both these abnormal inundations
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