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e. reCOnStruCtInG SeA LeVeL AnD COAStAL CHAnGeS evaluated, as they can drastically change the results.
Sea-level Markers: Archaeological features asso- In order to eliminate the possibility of biased re-
ciated with the sea often record and preserve the construction of sea level due to settling and collapse
location of the coastline and the sea level at the time of anthropogenic features, installations quarried in
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of their construction and functioning, and thus may the bedrock were studied . Three considerations
be used as sea-level markers. Each marker has its were taken into account to evaluate the magnitude
own accuracy and limitation and may provide data of vertical earth crust changes in the region: 1) com-
on higher or lower possible elevations of palaeo-sea paring the local sea-level curve with global curves
levels, or on both. For example, coastal wells derived from tectonically stable regions. If a consid-
provide valuable information on the elevation of erable local subsidence had taken place in the region,
the water table and the elevation of the highest and it should have placed the local curve below the glob-
lowest possible palaeo-sea levels at the time of op- al curve, and vice versa, 2) studying natural features
eration . Living floors, on the other hand, can only formed during the last 4000 years, that are associated
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provide the highest possible sea level at the time of with the present sea-level elevation. These include
occupation. Sea-level markers usually provide infor- depositional features (beach rocks that are always
mation on the relative land-sea relation. Thus, when embedded in the intertidal zone), erosional features
considering absolute sea-level change and associated (abrasion platforms and wave notches associated
coastal changes, other aspects should be considered. with the present sea level) and biogenic deposits
These include vertical earth-crust shifts (tectonic, (Vermetidae colonies which develop on the abrasion
structural or isostatic), settling of the archaeological platforms), 3) checking the elevation of beach de-
feature in unconsolidated sediments, erosion, sed- posits embedded during the last interglacial, high sea
imentation and collapse. All these processes could stand (MIS 5e isotope stage). The inner edge (The
have displaced archaeological features from their most inland deposition limit) of these deposits in a
original elevation and position, so that their present tectonically stable region should be at elevations of
elevation may not be associated with global eustatic ca. 6-7 m above sea level (fig. 3). Their recent eleva-
sea-level changes. To make things more complicated, tion above sea level may thus provide an estimation
usually several factors are responsible for a relative of average vertical earth crust changes during the last
change in sea level as derived from any archaeologi- 120,000 years and an estimated extrapolation can be
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cal marker . made for the Holocene .
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Modeling the palaeo coastline and its topog- It should also be noted that horizontal changes in
raphy: The study of archaeological and natural the location and configurations of a coastline are not
sea-level markers on the Israeli coast enabled the necessarily associated with vertical sea-level or earth
reconstruction of an estimated curve depicting the crust changes. Coastline shifting may be the result of
changes in sea level for the region (fig. 24). For ex- erosion or sedimentation. In Haifa Bay, for example,
ample, the water wells from Atlit-Yam suggest that the coastline was ca 4 km east of the present coast-
when the site was occupied ca. 9000 years BP, sea line at ca 4000 years BP, and since then has shifted
level was ca. 16 m lower than at present (Fig. 25), westward to its present location, without any change
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while the wells from Kfar Samir suggest that ca. in sea level . Thus, bathymetry alone cannot be a
8000 years BP, the sea level was ca. 9-10 m below its basis for reconstruction of the palaeo-coastline. In
present level. the northern Carmel coast, the local sea-level curve
When reconstructing changes in the location and derived from the archaeological data, the informa-
the configuration of a coast, the estimated local tion gained from the bathymetric maps, sub-bottom
sea-level curve and the bathymetry are the key fac- profiling and jet drilling carried out in the region (see
tors to be considered. However, the tectonic stability above). All these were used to reconstruct changes in
and the sediment patterns in the region should be the configuration of the coast over time (Fig. 26).

66 GALILI- NIR 1993; NIR 1997,
67 For more details on the use of archaeological and geological sea-level markers see GALILI et al. 1988, 2005a; GALILI et al.
2015b; BENJAMIN et al. 2017; GALILI et al. in press passim.
68 GALILI-SHARVIT 1988,
69 GALILI et al. 2015b, 2017b,
70 ZVIELY et al. 2006,

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