The 1586 M~8 Tensho earthquake might have been one of the largest inland earthquakes in Japan. Historical documents and geologic evidence suggest that there might be a composite rupture process involving more than a couple of active faults. To retrospectively evaluate such a possibility of distant cascading ruptures with stress transfer hypothesis, here I compute the static Coulomb stress changes under two representative scenarios. One is the Shogawa fault, Atera fault, and Yoro-Kuwana-Yokkaichi fault zone have been the sources(Sangawa’s scenario), while the other is a movement of the norther Shogawa fault followed by the Yoro fault or Isewan fault (Matsu’ura’s scenario). To assess the imminency and instability of their earthquakes in 1586, I also take the 30-yr earthquake probabilities of the causative faults into account. Computed stress transfer in five out of six combinations in the Sangawa’s scenario suggests that Coulomb stress on the subsequent rupturing fault is loaded by the previous earthquake by up to 0.5 MPa. On the Matsu’ura’s scenario, amount of stress transfer by the northern Shogawa fault to the Yoro or Isewan fault would be smaller than 0.01 MPa. But such small stress perturbation including possible effect of dynamic shaking might have been enough to trigger the Isewan fault which had been on the verge of the next rupture. Although there are still large uncertainties to assign fault parameters, my preliminary computations imply both scenarios can be supported by the recent consensus of static stress transfer hypothesis.

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本論は、 15年・京都の微視的景観の復原を通じて、歴史的都市における高密度化の過程を捕捉した。街区の細分化の程度やたて込みの程度にばらつきがある、多様な景観を復原的に得た。通時的な傾向として、漸進的に高密化が進行していく過程が見通された。個々の場所による多様性は、この高密化の進行過程における諸段階の違いである。まず、ある疎らな場所でたて込みが増強する。たて込んだ《物》に対する権原が、その設置場所である土地にもおよぶ。たて込みは土地の細分化を促す。細分化された土地の面的な広がりが都市域の形成である。つまり、都市は家々が《物》を増やしていくことによって密度を高め、面積を広げていった。すなわち、この高密化の起点として、家があった。本論は、歴史的な都市域の形成の核として、家を見出した。

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