The precise manner in which the slopes of the Palestine watershed fall towards the Ghôr differs in the different regions, but in principle it is the same throughout; there is everywhere a violent contortion of the strata, sometimes forming a fault or fissure running north and south, and sometimes a sharp dip down eastwards. We first studied the section above the Bukei'a, near Mar Saba, and here, as I have before noticed, there appears to be a well-defined fault. In the neighbourhood of Fusâil I found the rocks tilted up at an angle of 30°, and the same violent contortion has formed the great fissure of Wâdy el Hamâm, west of the Sea of Galilee. The Fâr'ah Valley is a great rent seemingly due to the same causes, and thus the whole of the geological evidence goes apparently to prove the occurrence of a violent and probably sudden collapse of the whole Jordan Valley commencing north of the Sea of Galilee.
This depression must have taken place at a comparatively late geological period; all the cretaceous rocks had been deposited before it occurred, for their strata all dip down east, on the west side of the valley. There are even the means of fixing the period pretty exactly, for there are marine formations deposited on the cretaceous rocks which seem to have no dip, namely, the coloured marls and bituminous limestones which occur at Neby Musa, and again at the edge of the plain of Beisân, in the first case 200 feet higher than the Mediterranean, in the latter, 200 feet below that level; these strata are, I believe, attributed to the Eocene period. It appears that even at an earlier epoch the region was bituminous: the latest of the cretaceous formations disturbed by the depression contain bitumen which seems to have been once liquid, and, near Masada, there are even black bituminous stalactites on the rock. The Eocene coloured marls contain innumerable fossils, and the formation appears to have been deposited under water. It is probable that in Eocene times the Dead Sea reached up nearly to Hermon, and to the Red Sea, with which the Mediterranean must have been then in full connection, as the Isthmus of Suez had not then been formed.
A further change was wrought still later, for the convulsions which were accompanied by the great outflow of lava which has covered so large a district west and north of the Sea of Galilee, and in the Lejja country, are, I believe, dated by geologists as of the Tertiary period, and in one place the lava appeared to me to overlie the coloured marls. The chain of Gilboa, Little Hermon, and Tabor, with the Galilean hills, have all been more or less affected by this volcanic disturbance, and perhaps the depression of the valley may then have increased still more.