The Archaeological Geology of Tel Yin'am, Galilee, Israel
Tel Yin'am, in Lower Galilee, has been continually inhabited by people for thousands of years, from the Neolithic to the Roman Empire. Set in an alluvial fan at the base of a basalt fault scarp, this was an excellent location for a settlement, offering good water supplies, abundant pre-sized building stones, and fertile soil.
First archaeological excavations were carried out here during the late 1970s. The valley drops to around 57m below sea level and has been identified with Biblical Yavne'el, a southern border town of the Naphtali tribe.
The tell features a comparatively small, roughly distinct circular mound c. 85m in diameter and 7m. high, together with a huge, imprecisely defined far-off settlement of yet uncertain size and shape. There has been human occupation here from the Neolithic period (7000 BCE) through the Early Byzantine period (3rd -6th centuries CE), with gaps in occupation during Early Bronze II to Late Bronze I inclusive (2900 - 1550 BCE), and the Hellenistic and Early Roman Periods (4th – 1st centuries BCE). “On the basis of our current reconstruction of the history of occupation at the site, the Middle Bronze to Early Byzantine settlements, and possibly the Neolithic and Chalcolithic settlements as well, were restricted to the small area represented by the mound, while the Early Bronze I settlement occupied a very large area consisting of the lower levels of the mound and the outlying settlement”.
A large percent of the rock crops in this area are alkali-basalts, pushed out 40,000 years ago by a series of volcanic eruptions. The basalts near the tell date from between five to 15 million years, representing “a vast sheet of lava (the Hauran) that spread over much of Syria and Jordan for 200 miles east of the Sea of Galilee”.
The alluvial fans probably began to form the same time that the faulting commenced around a million years ago but appear to be inactive today. There were good reasons for building a settlement here - the natural slope of the alluvial fan provides good drainage, reducing the risks of floods, as well as providing good lookout positioning for when enemies came charging down the valley.
As this part of the world is very dry, alluvial fans are a good source of underground water supplies. When the rain falls, the water is collected in the canyons and is sluiced down to be collected in the porous and absorbent gravels. The ancient people needed only to dig shallow wells to have a good source of water at hand.
Basalt was by far the most important material used at the tell, making up around 99% of the material used for building walls and pavements at Tel Yin'am. “There are two basic types of basalt, both of which are mainly dark gray (N4, Munsell Soil Color Chart). Ordinary basalt is very fine grained, and has few or no holes or vesicles in it because it crystallized at some depth under relatively high pressure. Vesicular basalt is full of gas bubbles produced when the lava flows out near the surface and undergoes a decrease in confining pressure, like Coca-Cola frothing out of a shaken can when one opens it; such basalts can have 5-50% by volume of holes”.
It appears that the site was abandoned sometime in the 7th century. Scholars are not certain, but it appears that the area’s agriculture could not support the community. Long summers of drought would continue into the autumn and winter, making the ground harder to toil and produce the crops they desperately needed.
Liebowitz, Harold & Folk, Robert L. (1980) Archeological Geology of Tel Yin'am, Galilee, Israel, Journal of Field Archaeology, Boston University.