The 15th typhoon named Rusa hit Korea during in August 31 to September 1. It caused serious damages particularly in the eastern region where the heavy rainfall concentrated, triggered debris flows, slope collapses and flood water inundations in major rivers. Many surface failures and debris flows occurred especially on the burned slope by forest fire, in addition, tremendous volume of sediment flowed into rivers and caused dangerous aggradations. Accordingly, it is imperative to control the discharged sediment by installing sabo dams.

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朝鮮半島北東部に卓越する複列型間取りの民家は，東海岸沿いのやそこから西方ないし南西方に分岐する支脈をたどる形で，かなり南方までその分布が確認されている．しかし，本発表で引用した全羅南道海岸島嶼の事例は，そこからかなり隔たった場所で発見されており，他地域との関連については，まだ検討の余地が大きい．今後，周辺地域での類似間取りの存在や全羅南道山間地域の間取りとの連続性なども確認しながら，続報を試みていきたい．

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台風は, 環境への大きなインパクト, 災害の外力となる気象現象であり, これにより発生する局地的で強い風域場, 降雨場の再現は海岸工学上, 極めて重要な外力シミュレーションである. 本研究では, 簡易台風モデル (光田・藤井モデル) とMASCONモデル, さらにメソ気象モデル (MM5) による風域場の比較を行う. 次いで, 洪水や集中豪雨による河川・海岸系での土砂輸送問題に必要な, 豪雨のシミュレーションが, MM5でどの程度再現できるかを検討する. 台風に伴う強風場の再現性の評価は, 台風9918号による周防灘での高潮シミュレーション結果により行った. 一方, MM5による豪雨解析では, 台風0215号により発生した韓国東海岸で総雨量900mm以上の降雨場の再現計算を行った.

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韓国東海岸地域の地形発達を第四紀地史の中に正しく位置づけるために, 河成段丘地形が比較的よく発達する珠樹川流域を取り上げ, 段丘堆積物, 古土壌, 斜面堆積物および段丘縦断面形の検討により, 段丘面の対比および編年を行なった。その結果, 最終氷期の堆積段丘である山渓I段丘と, それに先立って形成された玉渓段丘 (中流部のサンバナム段丘) の存在が明らかになった。古土壌の発達状態などからみて玉渓段丘は最終間氷期に編年される可能性が大きく, 河口部における同段丘の高度は海抜17～19mと推定された。

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Pohang coastal plain, located along the Yeongil Bay, southeast coast of Korea Peninsula (Fig. 1), has marine and fluvial terraces, beach ridges, natural levee and back marsh. The writer tried to clarify the geomorphic development of this area.
Marine terraces along the coast of Yonghan-Ri are classified into three levels according to their altitude and continuity, namely surfaces I, II, and III in deceding order. These surfaces are originally abrasion benches cut into Tertiary bedrock, and covered with terrace veneers of gravel and sand bed of marine origin. Surface I is dissected by shallow channels and its surface soil is a little reddishly weathered. But surfaces II and III are scarcely dissected.
Fluvial terraces along the Neng-Cheon River are classified into three levels according to their relative height above river bed and continuity, namely surfaces I, II and III in desending order. Surfaces II and III are submerged by alluvium near the coast.
Two rows of beach ridges are recognized along the shore line. The outer one is continuous and relatively higher and the inner one is uncontinous.
Three groups of the natural levees are recognized along the Hyungsan River. The first group is scattered at the north side of river. The second group is well continued at the south side of river. The third one has been formed by the present course of Hyungsan River.
The writer measured radiocarbon dates of 7 samples from boring core and alluvium outcrops (Fig. 5), and analyzed grain side distribution of deposit from boring core No. 13 (Fig. 6). Based on the radiocarbon dates and grain size distribution, the writer drew the transition curve of sedimental environment in Pohang area (Fig. 7).
On the consideration of land classification and transition curve of sedimental environment, experienced the geomorphic development this coastal plain as follows:
1) The marine terrace surface I was formed at the high sea level during Last Interglacial. Surfaces II and III were formed at any stable period of lowering sea level to Würm or at the relatively high sea level in Würm Glacial.
2) The fluvial terrace surface I was formed at the same period of marine surface III formatioon. Surfaces II and III were formed at Würm maximun or at any stable period of rising sea level of Post Glacial.
3) Concerned with the Post Glacial word wide transgression, the sedimental environment in Pohang coastal plain changed as follow:
There was a stabe period about 10, 000 y. B. P. in rising sea lfvel of Post Glacial transgression, when the old valley of Neng-Cheon River was submerged and deposited by lower gravel bed (MG) shown at 20m below sea level in boring column.
The sea level about 6, 000 y. B. P. was fairly close to the present sea level, and since then it has been relatively stable with slight oscillation until the present, and natural levee and beach ridge have been formed during that time.

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All hot spring waters of non-volcanic origin are mostly distributed in the plutonic masses of the Cretaceous Bulkuksa granites and the Jurassic Daebo granites in the central and southeastern parts of the Korean peninsula. Temperature and pH of the hot spring waters range from 28.5° to 67℃ and from 6.55 to 9.40, respectively. Dongrae and Haiundae hot springs are located on or near the fault line, but others are not directly related to the fault structures. The ranges of δ¹⁸O and δD values for the hot spring waters are from -6.5 to -10.7‰ and -48.7 to -73.8‰, respectively, and for the local surface waters from -5.5 to -10.1‰ and -39.5 to -70.7‰, respectively. On the basis of stable isotopic and chemical compositions of the hot spring waters and geographical distribution of the hot springs in Korea, the hot spring waters can be divided into following three types; (1) Backam type characterized by low δ¹⁸O and δD values and alkaline waters. (2) Onyang type with weakly alkaline and intermediate isotopic values. Relatively high content of F^- and low Na⁺, Cl^-, and SO₄^2- contents. (3) Haiundae type, having high δ¹⁸O and δD values, weakly alkaline, and high concentration of Na⁺, K⁺, Ca²⁺, Cl^- and SO₄^2-. Most of the oxygen and hydrogen isotopic values are plotted slightly below the meteoric and surface water line defined by CRAIG (1961), and show a gradual decrease of the heavy isotope concentration from south to north, and west to east in the penin- sula possibly due to temperature and altitude effects. The hot spring waters are characterized by δ¹⁸O and δD values that are lower than those of the local surface waters at or near the hot springs, suggesting that the hot spring waters are derived from geographically further northern districts and topogra- phically higher mountain regions. The δ³⁴S values of dissolved sulfates range from +5.5 to +29.3‰, apparently reflecting the different sources of the sulfates for different hot springs. Sulfates of the hot spring waters from Haiundae and Pohang may be originated from sea water sulfate and those from Yusung, Duggu and Echon from the secondary sulfate produced by oxidation of sulfide minerals and the mixtures of the above two are thought to be responsible for Suanbo, Duksan, Dongrae, Magumsam and Chucksan hot springs.

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There are two types of groundwater in the Korea.One is the groundwater containedin the unconsolidated rock system, the other is the groundwater existing in the consolidated rock system.In this report only the latter type of groundwater is discussed.
Geologically the Korean Peninsula is a part of Continental China.In terms of geogical time the ages concerned with the formation of sedimentary rocks range from the Pre-Cambrian Era to the Tertiary Epoch of the Cenozoic Era.In Palaeozoic deposits there are many limestone beds, and Mesozoic deposits oftentimes contain limy shales.Groundwater in sedimentary rocks is usually contained in limestones or limy rocks. Groundwater can also be found in igneous rocks and metamorphic rocks which are derived from old sedimentary rocks.
Groundwater in the sedimentary rocks is fissure and stratum water, and in igneous rocks and metamorphicrocks only fissure type water exists.
Results of the study made by drilling wells in various types of rocks, the following facts are made clear: In consolidated sedimentary rocks largest quantity of groundwater is found and next in quantity comes the groundwater from granite.On the contrary, the groundwater in metamorphic rocks is found in smaller quantity than in any other rocks.
With respect to water quality, the groundwater in granite and metamorphic rocks isbetter than the groundwater in sedimentary rocks.The groundwater in dike rocks is also good.Anyway all the groundwater from these rock systems is good for agricultural use and drinking purpose.
In the Korea the shallow groudwater is easily affected by the surface water and gets polluted.The deep groundwater on the contrary is not easily influenced by the surface water body and has the advantage of constant temperature.
In developing the groundwater to meet the demand for water, unpolluted and with constant temperature, it is necessary to investigate carefully on these points.

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洛東江 (Nakdong R.) の河床縦断面形と勾配の変化,河床砂礫の粒度組成,河道の幅と氾濫原の広さ,流域の地質等を検討し,平衡作用を中心に河道の形成機構を考察した.その結果次のことが明らかにされた.
洛東江は全流路が平衡に達した典型的な河川だと言われてきたが,その縦断面形を細かくみると,傾斜を異にする幾つかのセグメント (segment) からなり,各セグメント毎に縦断勾配が指数曲線的に減少して平衡状態を維持していることが明らかになった.そこで筆者はこのようなセグメントを平衡区間 (graded segment) と名づけた.したがって洛東江の縦断面形は,このような平衡区間の連続からなり,各平衡区間の勾配は,下流ほど緩やかで波長も長くなっている.
また平衡区間は地質の分布とほぼ一致し,各平衡区間の境界は岩質の差で狭窄部または峡谷をなし,平衡作用の局部的基準面の役割をしている.河床砂礫の粒度組成も平衡区間毎に変化を示し,河道または氾濫原の幅も,各平衡区間の境界地域では狭く,平衡区間の中間地域では広くなる.したがつて河道または氾濫原の幅を中心とする河道の平面形状も狭窄部と拡張部の連続で,河床の縦断面形における平衡区間と対応している.

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In any economic structure of a region with regard to supply and demand, one of the important criteria is freight flow that exists between regions. It was ascertained that ton-km of freight flow by rail is the most important in Korea.
In this thesis, an attempt is made to clarify the spatial pattern and to build traffic core regions. This is to clarify the characteristics of traffic core regions on freight flow by railroads in Korea.
For this purpose the flow pattern of freight was analysed by the Q-mode and the R-mode factors. Traffic core regions determined by group average and multiple linkage analyses, and the character of the origin and destination were analysed.
Flow data in this paper emanate from matrices produced by the Office of the Korean National Railroads contained in part in their publication estimates of Korean Inter-Zonal Freight Flow, 1977. Estimates were produced by total rail freight flow (tons) between 56 zones.
Major findings are as follows:
(1) Freight flow by origin and destination by rail determind 10 types of flow patterns. In addition, this flow structure was added to local and regional flows on the basis of national flow (double stucture).
(2) In the traffic core regions that resulted by analysis of the flow pattern, there are 8 traffic core regions by outflow (Cheolam, Gohan, Dogye-Bugpyeong, Ssangryong-Jecheon, Daecheon, Yeosu-Hwasun, Mungyeong, Ulsan) and traffic core regions by inflow were builded 2 regions (Seoul, Busan).
(3) Centralality was measured by eigenvalue and factor score, and the order of traffic core regions by outflow consisted of Ulsan, Gohan, Cheolam, Ssangryong-Jecheon, Mungyeong, Yeosu-Hwasun, Dogye-Bugpyeong and Daecheon. The order of traffic core regions by inflow consisted of Seoul and Busan.
(4) The traffic core regions by outflow are constituted by regions producing underground resources and heavy-chemical manufacture. Traffic core regions by inflow are constituted by large consuming and developed areas of manufacturing. Finally it may be difficult to determine the factor of freight flow by rail; however, it is explained more or less by the relationship between underground resources, population and manufacturing in Korea.

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