DEAD SEA, an intensely saline lake occupying the southern end of the Jordan Valley, called in Scripture the Salt Sea (יָ֥ם הַמֶּֽלַח, Gen 14:3; Num 34:3, 12; Deut 3:17; Josh 3:16; 15:2, 5; 18:19); the Sea of Arabah or (KJV) Plain (יָ֤ם הָֽעֲרָבָה׃֙, Deut 3:17; 4:49; Josh 3:16; 2 Kings 14:25); and the East(ern) Sea (הַיָּ֥ם הַקַּדְמﯴנִ֖י, Ezek 47:18; Joel 2:20). Other names include the Arab. Bahr Lût, “the Sea of Lot,” Lake Asphaltites (Josephus Antiq I. 9. 1) and the “Sea of Sodom” (Talmud).
The Dead Sea is a remarkable geographical feature and a pivot point of history. Filling a segment of the great Afro-Asian Rift Zone and the deepest of continental depressions, with a shoreline 1300 ft. below the Mediterranean surface and a floor plunging 1300 ft. deeper, it forms a sheet of greenish water extending almost fifty m. from the muddy salt flats of the Jordan delta in the N to the scrubby marshland of the Sebkha in the S. Constricted by the mountain walls of Judaea and Jordan, it is scarcely eleven m. across at its broadest and narrows to two where the Lisan or “Tongue” Peninsula divides the 294 square m. of the deep northern basin from the 99 square m. of the shallow southern basin. Yet this harsh lifeless sea is notable for its geological structure, its hydrology, its natural resources, and its role in Biblical history.
1. Origin and structure. If the geological signs have been read right, the Dead Sea was initially formed when a Miocene “earth storm” trapped the fringe of the ancient Mediterranean (or “Tethys”) between the walls of the subsiding Rift, and when the inland sea that once extended from the slopes of Hermon to the central Arabah subsequently shrank into the residual water bodies of Huleh, Galilee and the Salt Sea. The earth storm left its legacy of abrupt walls, plunging strata and crustal weakness. Tethys left its deposits as the thick strata of hard limestone and soft chalk that form the Judean hills and cap the continental crystallines and “Nubian sandstones” of Trans-Jordan, while the trace of fluctuating shorelines is left in elevated terrace and crumbling deposit. A gross oversimplification, for the pattern was complicated and modified by cross currents of crustal movement and climatic change—particularly the alternation of pluvial and arid phases that correlated with the advance and retreat of the European ice sheets.
During the three major pluvial periods the Dead Sea expanded to form terraces high in the walls of the Rift, while a simultaneous acceleration of erosion creased the valley slopes with wadis and spread thick deposits across the valley floor—masses of gravel that choked the wadi exits, beds of rock salt and gypsum, shale and clay, sand and soft chalk, along with the ash gray or yellowish marls that form the Lisan peninsula and bleach the terrace lands of the Jordan. Subsequently exposed and eroded during arid phases, such marls crumbled into the intricate chaos of corrugated “badlands” that flank the Ghor, and the Jordan carved the jungled trench of the Zor. Crustal deformations depressed and tilted the northern basin of the Dead Sea, perhaps simultaneously upthrusting the mass of rock salt and gypsum that forms Mt. Sodom (Jebel Usdum). The subsequent breaching of the Sodom-Lisan ridge and the flooding of the southern basin may well be events of historic times, hypothetically burying the Vale of Siddim with its ruined cities (cf. Gen 14:3).
Sodom and Gomorrah apart, instability is a recurrent feature of this structural “shatter belt.” Intermittent earthquakes, submerged trees, a Rom. road traced to the vanished Lisan crossing, the fording of this now deeper sill as late as 1846—all manifest the continuance of ancient crustal weakness. The faulting was complicated. Apart from the primary faults that shaped the Ghor, the downward pull of subsidence tilted the flanking strata into plunging monoclines, while diagonal “hinge faults” splintered the adjacent scarps to form the Plain of Moab and create zones of weakness subsequently deepened into the sawcut river gorges of the Moab scarp.
2. Springs and seepages. Crustal weakness also released a variety of subsurface materials. The rock salt of Mt. Sodom, pressured and plastic, apparently exuded through broken cap rock, while springs—hot and cold, fresh and mineral—issued forth. Patches of greenery mark the sites of fresh-water springs such as those of Zo’ar and En-gedi, while hot and sulphurous waters like those of Zerka Ma’in long have been accounted therapeutic. Submarine sources send salt water as well as fresh welling into the sea floor, contributing, moreover, such minerals as bromide and sulphur that exclude all but a modicum of bacterial life, and impart the distinctively bitter taste and nauseous smell of Dead Sea water. Exhalations of gas and seepages of petroleum and esp. bitumen occur, the latter impregnating chalk and limestone to furnish trader and artisan with coal-like “Dead Sea stone” and welling to the sea’s surface particularly after earthquakes; the “slime pits” (Gen 14:10) may well have been bitumen seeps. In all likelihood—since volcanic eruption is geologically improbable—it was an earthquake accompanied by the explosive ejection of gas, bitumen and rock salt that wrought destruction to Sodom and Gomorrah.
3. The salty sea. While the sea derives something of its saltiness from surface or subterranean springs along with sporadic runnels from Sodom rock salt, some salinity is added from the soils of the arid watershed. The four permanent streams that drain the rainier uplands of Moab—the ’Udhemi, Zerqa, Arnon and Zered—along with countless intermittent wadis, all carry their quota of salts, while the Jordan, which supplies about 6,500,000 of the 7,000,000 tons of daily inflow, has a high content of sodium and magnesium chloride.
Nevertheless the salt sea would be fresh or only mildly saline had it an outlet: but the landlocked basin in a hot and arid climate forms a superb evaporating pan. The desert climate, accentuated by the rain shadow of the Judean uplands and the hot, gusty winds that pour downslope to the Ghor, is here intense. Scarcely four erratic inches of unreliable precipitation fall annually at the northern end, while the S has less than two. Dry heat accelerates evaporation. Relative humidity is only fifty-seven per cent, average annual temperatures (though reduced by the inclusion of moderate winters and the marked nocturnal cooling of the desert) reach 77oF in places, with individual days soaring to 124oF in the almost non-existent shade—to say nothing of fiercer heat in the glaring sunlight. True enough, occasional winds from the moderate N and regular onshore breezes generated particularly by the northern basin may temper the heat, but they also increase the evaporation. Though this is reduced by high barometric pressure and its own concomitants of light surface mists and high salinity, evaporation remains intense enough to balance the daily inflow of 7,000,000 tons and maintain a fairly constant level. There are seasonal and long term oscillations, of course, which render the 1963 mean of “1308 ft. below” somewhat theoretical: winter levels seasonally rise some ten to fifteen ft. above those of summer, while cycles of relative wetness or drought in the Jordan catchment area—along with more hypothetical crustal deformations—may produce cumulative changes. The rising trend of recent centuries gave way to sinking shorelines after 1929, and measurements since 1900 record a rise of thirty-seven, and fall of sixteen ft. Walled in to E and W, the shoreline perforce expands or contracts at its shelving ends, sometimes inundating the Sebkha for several miles.
4. Mineral extraction is concentrated at these shallow ends. The western shore has long yielded “Dead Sea stone,” and salt has been collected for distant markets and temple sacrifice from Sodom and the southwestern Lisan. Arabs and Romans inherited an ancient trade and the Madeba mosaic depicts the passage of a salt-laden Byzantine vessel. Massive extraction awaited the rising demand for chemicals—esp. fertilizers—and in the Mandate period the Dead Sea became a treasure trove. Apart from such crystallized minerals as gypsum (calcium sulphate) and common salt (sodium chloride), which veneer the lake floor, the water—surpassed only by Turkey’s Lake Van—sustains a twenty-five per cent concentration of mineral salts, a percentage rising to thirty in the shallow southern basin and thirty-three at depth. As individual elements it is chlorine, potassium, and sodium which are dominant, with sixty-seven, sixteen and ten per cent respectively, while bromine, potassium, calcium and sulphur are present in the small but essential amounts critical for combination into the immense tonnages of salts that saturate the sea—22,000,000,000 tons of magnesium chloride, 11,000,000,000 tons of common salt, 6,000,000,000 tons of calcium chloride, 2,000,000,000 tons of potassium chloride, 980,000,000 tons of magnesium bromide, and 200,000,000 tons of gypsum. Furthermore, the mass of Jebel Usdum preserves a vast residue of rock salt from a larger sea.
Initiated by the Palestine Potash Company at Kallia in 1929, extraction was expanded in 1934 to the subsidiary but ampler site of Sodom, now the focus of production. With the wreckage of Kallia behind the Jordanian lines, and with the Beersheba road completed in 1952, the present pattern took shape. A bromide factory built in 1955 has been merged with a revived and expanded “Dead Sea Works,” rock salt quarried from Sodom, and a complex of evaporating pans extended around and into the water. The brine, conducted into pans, deposits common salt before evaporating to leave the carnallite which yields first potash and then bromine. With potash production multiplied fourfold between 1960 and 1965 and doubling again to 1,000,000 tons by 1971, with the addition of table salt refining, with natural gas delivered from the newly-discovered Arad field and with bromine-bottling established at Beersheba, a distinctive industrial complex has emerged.
5. Agricultural resources,by contrast, are uninviting. Even the Bedouin flocks find little sustenance in scanty grass and thorny scrub which occasionally thickens into a scatter of acacia, and in ancient times, when irrigation agriculture was patchily intensive at wadi mouths, most of the region was apparently used only intermittently from peripheral upland settlements. Even the tangle of reed and tamarisk typical of wetter patches may cover soils of repellent saltiness, and “Dead Sea fruit” (Calotropis procera) is an appropriate metaphor—a ball of threads and air. Nevertheless, islands of greenery, often dominated by spina Christi, occur around fresh water springs, which (skillfully utilized) can sustain a varied range of crops and livestock.
A series of actual or potential settlement sites are aligned along the Dead Sea shores. Little significant development has characterized the eastern side, for (despite the ampler streams of Moab) cliffs crowd the shoreline to eliminate route ways, and the gorges that cleave the sandstone cliffs offer little in the way of level and cultivable land. Settlement, however, could lodge at the northern end where the well-watered Plain of Moab gave Israel a base (Num 22:1), at Callirhoe (prob. Zara S of the Zerqa Ma’in) and particularly in the fertile depression extending from the backslope of the Lisan Peninsula to the delta of the Wadi el-Heso or Zered. Though this oasis belt has a considerable potential for intensive and varied production, it lacks the essential stimuli of access to markets and cultural or historical conditioning: despite some cropping and grazing it remains only patchily developed. However, the descent of five streams from the adjacent escarpment has suggested one hypothetical location for the five cities of the plain.
The western shore, by contrast, is better developed: water supplies may be meager but the mountains shelve less brusquely to the lake, and ancient route ways could not only thread the beach but penetrate the Judean uplands from the three oases of ’Ain Feshkah, En-gedi, and Jericho. Jericho lay eight m. to the N, but springs such as ’Ain Feshka near Qumran, ’Ain el-Ghuweir, ’Ain el-Turaba and esp. the splendid oasis of En-gedi enabled settlement to lodge along the shoreline. Three elevated springs sent water cascading from the cliffs to the sea, sustaining the irrigation settlement of Hazazon-tamar (En-gedi) in Abraham’s day (Gen 14:7; 2 Chron 20:2): gracious with vineyards and gardens in Solomon’s time (Song of Solomon 1:14), it now nourishes a kibbutz, rich with tropical oasis crops.
6. Historical role. Typically enough, En-gedi’s backdrop is a barren chaos of crags and wadis that gave refuge before ever the fugitive David sought its fastnesses (1 Sam 23:29), a barrenness reinforcing the general impression of lifeless shores around a lifeless sea. In Scripture the region is characteristically a scene of judgment or of battle. Chedorlaomer overwhelmed the Palestinian kings and swept Lot into brief captivity (Gen 14:12) and somewhere hereabouts—perhaps beneath the southern embayment—lay the cities whose destruction reverberated through history and prophecy. The eastern escarpment, seamed by the canyons of the Arnon and the Zered, recalls the thrust and counterthrust of Edom, Moab and Israel, as do the heights behind En-gedi (2 Chron 20:2). The Moab rim gave Moses a glimpse of the Promised Land across the Rift, while the plains of Moab and Jericho witnessed the passage of the invader. The hot springs of Callirhoe gave momentary relief to the dying Herod, while among the opposing cliffs of Judea, the Qumran community meditated and wrote. The fortress of Machaerus, traditional site of John’s beheading, crested the eastern scarp, while the western shores were dominated by the outthrust mesa of Masada, grimly reminiscent of the Zealots’ last stand as the Temple lay in ruins. But, in a vision of Messianic healing, the role of the Dead Sea changes. The harsh wadi of the Kidron fills with the fresh waters of healing that flow from the Temple to the Sea, and though the marshes still yield their salt, the once lifeless waters now swarm with shoals of fish (Ezek 47:9, 10).
Bibliography W. F. Lynch, Official Report of the United States Expedition to the Dead Sea (1849); G. A. Smith, Historical Géography of the Holy Land (1931); F. M. Abel, Geographie de la Palestine (1933-1938); (British) Naval Intelligence Division, B. R. 514, Geographical Handbook Series, Palestine and Transjordan (1943); D. Baly, Geography of the Bible (1957); Geographical Companion to the Bible (1963); E. Orni and E. Efrat, Geography of Israel (1966).