国立情報学研究所 - ディジタル・シルクロード・プロジェクト
『東洋文庫所蔵』貴重書デジタルアーカイブ
|
|
カラー画像サムネイル -
目次 -
ページ番号 -
書誌情報（メタデータ） -
キャプション -
カラー画像 -
白黒高解像度画像 -
見開きページ -
グラフィック -
| 0451 |
Southern Tibet : vol.7 |
| 南チベット : vol.7 |
引用情報
OCR読み取り結果
correctly says, becomes fresher as one goes eastward. The saltness denotes that
the lake has no outlet. The supply of water comes mostly from glaciers. Some,
he does not know how much, comes from the upper lakes through the channel at
Ot. The information he got that the lake is frozen three months in winter is not
correct, for only the upper, fresh, lakes freeze.
At 14, 3, and 7 feet he saw marks of higher levels of the lake. As to high
beaches, his observations were confined to the southern side of the lake. At many
places he found beaches at levels of from 40 to 50 feet above the present level of
the water. Margin-marks occurred at various levels up to 100 or 120 feet.
He tries to trace the origin of the formations of Panggong-tso, mentions Trotter's
maximum depth of 142 feet, and Godwin-Austen's finding the true cause of the
lake to be the damming of its waters by side alluvial deposits.
Speaking of the N. W. corner he says: »Tracing on in this direction the
highest margin-marks (those 100 or 120 feet) we find them to end against a fan,
composed of gneiss, that comes out of a steep valley on the south-west, and abuts
against the opposite (N. E.) hill boundary of our gorge . . . .» This then is what
dammed the waters at the highest level to which we have traced them; it is the
fan described by Godwin-Austen, and the place is Surtokh. There are other, lower,
fans which at earlier periods may have been forming dams in the same way.
From this material Drew makes his deduction regarding the history of the
formation of the lake. First a tributary of the Shayok went through the valley viâ
Tankse. Then the fans were formed which dammed up the valley, and the lake
came gradually into existence. Then followed a dry climatic period, the lake re-
turned eastward, diminished and became salt. Drew believes that at levels below
50 feet the surface of the lake remained unchanged for longer periods than above
50 feet. Every one of the upper lakes in the Panggong-tso has, in his opinion,
also been formed by fans.¹
From our regions, south and north of the Kara-korum, Drew has some interesting
observations.² For Rupshu he prefers the term »high-level valleys» to that of plateau.
Only farther north he finds the terms plateau and table-land correct. »Between the
country which drains into the Shayok and that whose streams flow into the Kara-
kash or into other rivers of Eastern Turkistan, is an elevated mass of ground-plains
surrounded and crossed by rocky ridges — whence water finds no outlet, but dries
up on the plains themselves.» He estimates the area of the isolated drainage-basin
at no less than 7000 square miles. But he adds that »our knowledge of this tract
is but scant, and of a portion of it only conjectural».
1
.
.
.
.
|
.
.
.
.
17
.
.
.
.
|
.
.
.
.
28
.
.
.
.
|
.
.
.
.
38
.
.
.
.
|
.
.
.
.
49
.
.
.
.
|
.
.
.
.
60
.
.
.
.
|
.
.
.
.
70
.
.
.
.
|
.
.
.
.
81
.
.
.
.
|
.
.
.
.
92
.
.
.
.
|
.
.
.
.
105
.
.
.
.
|
.
.
.
.
117
.
.
.
.
|
.
.
.
.
128
.
.
.
.
|
.
.
.
.
138
.
.
.
.
|
.
.
.
.
150
.
.
.
.
|
.
.
.
.
161
.
.
.
.
|
.
.
.
.
177
.
.
.
.
|
.
.
.
.
190
.
.
.
.
|
.
.
.
.
202
.
.
.
.
|
.
.
.
.
214
.
.
.
.
|
.
.
.
.
225
.
.
.
.
|
.
.
.
.
237
.
.
.
.
|
.
.
.
.
251
.
.
.
.
|
.
.
.
.
263
.
.
.
.
|
.
.
.
.
277
.
.
.
.
|
.
.
.
.
291
.
.
.
.
|
.
.
.
.
302
.
.
.
.
|
.
.
.
.
315
.
.
.
.
|
.
.
.
.
329
.
.
.
.
|
.
.
.
.
342
.
.
.
.
|
.
.
.
.
352
.
.
.
.
|
.
.
.
.
363
.
.
.
.
|
.
.
.
.
375
.
.
.
.
|
.
.
.
.
386
.
.
.
.
|
.
.
.
.
397
.
.
.
.
|
.
.
.
.
407
.
.
.
.
|
.
.
.
.
420
.
.
.
.
|
.
.
.
.
432
.
.
.
.
|
.
.
.
.
444
.
.
449
450
451
452
453
.
.
457
.
.
.
.
|
.
.
.
.
467
.
.
.
.
|
.
.
.
.
478
.
.
.
.
|
.
.
.
.
488
.
.
.
.
|
.
.
.
.
499
.
.
.
.
|
.
.
.
.
510
.
.
.
.
|
.
.
.
.
520
.
.
.
.
|
.
.
.
.
530
.
.
.
.
|
.
.
.
.
541
.
.
.
.
|
.
.
.
.
552
.
.
.
.
|
.
.
.
.
563
.
.
.
.
|
.
.
.
.
573
.
.
.
.
|
.
.
.
.
583
.
.
.
.
|
.
.
.
.
593
.
.
.
.
|
.
.
.
.
605
.
.
.
.
|
.
.
.
.
615
.
.
.
.
|
.
.
.
.
625
.
.
.
.
|
.
.
.
.
635
.
.
.
.
|
.
.
.
.
646
.
.
.
.
|
.
.
.
.
656
.
.
.
.
|
.
.
.
.
666
.
.
.
.
|
.
.
.
.
681
.
.
.
.
|
.
.
.
.
693
.
.
.
.
|
.
.
.
.
704
.
.
.
.
|
.
.
.
.
714
.
.
.
.
|
.
.
.
.
726
.
.
.
.
|
.
.
.
.
737
.
.
.
.
|
.
.
.
.
747
.
.
.
.
|
.
.
.
.
758
.
.
.
.
|
.
.
.
.
773
.
.
.
.
|
.
.
.
.
788
.
.
.
.
|
.
.
.
.
801
.
.
.
.
|
.
.
.
.
813
.
.
.
.
|
.
.
.
.
833
.
.
.
.
|
.
.
.
.
848
.
.
.
.
|
.
.
.
.
864
.
.
.
.
|
.
.
.
.
876
.
.
.
.
|
888
Copyright (C) 2003-2026
National Institute of Informatics（国立情報学研究所）
and
The Toyo Bunko（東洋文庫）. All Rights Reserved.
本ウェブサイトに掲載するデジタル文化資源の無断転載は固くお断りいたします。
