巻号一覧
33 巻 (1987)
- 4 号 p. 299-
- 3 号 p. 171-
- 2 号 p. 89-
- 1 号 p. 1-
33 巻, 1 号
選択された号の論文の8件中1～8を表示しています
- |<
- <
- 1
- >
- >|
-
志知 龍一, 山本 明彦, 古本 宗充, 野崎 京三, 都築 輝昭, 角野 由夫1987 年 33 巻 1 号 p. 1-12
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーA gravimetric network for precise gravity measurements was established in the Tokai district, central Japan, which was known as one of the most active area of vertical crustal movement in Japan. The network consists of 57 gravity stations and the gravity values at 17 stations among them are selected very close within a difference of ±0.3 meals each other. The precise gravity measurements, which are aimed to detect a small gravity change associated with the crustal movement and to utilize them for the earthquake prediction in the area concerned, have been repeated three times a year since 1981. An unexpectedly large variation of the gravity changes is recognized at the stations whose gravity differences are large compared to that of the reference station. On the other hand, the variation at the station whose gravity values are very close to that of the reference station is very small. The gravity changes at the stations with gravity values close each other show similar patterns regardless of any local differences. This systematic and characteristic appearance in the patterns of the gravity changes suggests that it may be originated from the periodic irregularity of the composite gear system of the LaCoste and Romberg gravimeter employed for the present study. Although any effective method to correct this periodic errors has not been established yet at present, it is expected that a very small gravity change with a reliability of several μGals may be detectable.抄録全体を表示PDF形式でダウンロード (1768K) -
志知 龍一, 山本 明彦, 古本 宗充, 白木 秀明1987 年 33 巻 1 号 p. 13-20
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーA gravimetric route consisting of 12 gravity stations for precise gravity measurements was established in 1979 on the southern foot of Mt. Ontake, Nagoya prefecture, central Japan. The purpose of the gravity measurements was to observe a small gravity change which might be caused from the crustal movements associated with the seismic and volcanic activities in the area concerned where an earthquake swarm had been continuing around the southern foot of Mt. Ontake from 1976 and the phreatic eruption broke out at that mountain on October 28th 1979. The West Nagano Prefecture Earthquake, 1984 (M=6.8) whose fault plane was just crossing the gravimetric route took place on September 14th 1984. This paper describes a preliminary result of the precise gravity measurements with LaCoste and Romberg gravimeter G-484 carried out four times during the period from 1979 to 1984 that covers all of those events. Although the result shows an unexpectedly large variation of the gravity change which may be attributed to the cause of the periodic irregularity of the composite gear system of the gravimeter employed, a small gravity change with a reliability of several μGals may be detectable after a suitable correction for the periodic errors. The graity change during the period of present investigation is considered to be less than 100 μGals.抄録全体を表示PDF形式でダウンロード (1224K) -
柿原 利治, 瀬川 爾朗1987 年 33 巻 1 号 p. 21-32
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーNOAAのDCSを利用するシステムであるARGOSシステムのためのデータ送信用ビーコソと受信用LUT(Local User's Terminal)を開発し,それを使ってDCP(Data Collectioll Platform)の位置を決めるためのアルゴリズムを開発した.トラソスロケーション法により測位計算を行なった結果,±1kmの測位精度が得られた.抄録全体を表示PDF形式でダウンロード (958K) -
―潮位解析を例として―上條 賢一, 藤井 陽一郎, 青木 滋1987 年 33 巻 1 号 p. 33-39
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーA unified method to detect extraordinary features in time-series is proposed. Control chart for Quality Control is applied in this method. Detecting out of control limits (Upper Control Limit, Lower Control Limit) in control chart are tried as for extraordinary data. Both of UCL and LCCL are calculated by so-called 3 sigma method. 'RUN', 'TREND' and 'PERIODICITY' are used as assisting tools. Control charts applied to sea level data at Oga and Fukaura are shown as examples.抄録全体を表示PDF形式でダウンロード (631K) -
―境界要素法(2次元)による解析―柳沢 道夫1987 年 33 巻 1 号 p. 41-48
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーStrain changes observed by strain-gages in the tunnel of the Nokogiriyama Crustal Movement Observatory have good relation to atmospheric pressure changes. In order to explain this relationship theoretically, the author applies the two-dimensional boundary element method. It becomes clear that the induced strain changes are much affected by the topographic relief over the tunnel.抄録全体を表示PDF形式でダウンロード (751K) -
上條 賢一, 藤井 陽一郎, 青木 滋1987 年 33 巻 1 号 p. 49-60
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーObservations including geodetic observations should, in general, be performed syste matically. A method, named "Design of Observations" by the authors, is proposed, and its theory is based on the recent development of "Design of Experiments". It is possible to get orthogonal inf ormations efficiently from observation points by this method, in which the remarkable merit is that coefficient matrix in normal equations usually becames diagonal. In this paper, orthogonal theory is developed through a simple example. Covariances among estimators for unknown parameters are all zeroes, because the each vector in design matrix is intersected orthogonally each other. Therefore it is evident that those parameters can be estimated independently, and thus proposed method is very important for practical geodetic use. A comparison of this method with so-called "least squares adjustment" is also shown in the conclusion.抄録全体を表示PDF形式でダウンロード (871K) -
モハメド エリビアリ, 萩原 幸男1987 年 33 巻 1 号 p. 61-73
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリー人工地震・自然地震によって得られた速度構造をもとにして,東北および中部日本の密度構造を推定した.その結果,太平洋プレートの厚さを8Qkrnと仮定すると,プレートと周囲の物質との密度差は0.05～0.179/cm3であり,またモホ面における密度差を0.1～0.29/cm3と仮定すると,コソ.,ラッド面の密度差は0.07～0.099/cm3となることがわかった.さらに,これらの値を中部日本の重力データに用いることによって,フィリピソ海プレートの厚さは26～34kmと推定することができた。抄録全体を表示PDF形式でダウンロード (1349K) -
ボアホールの歪変形の孔井式傾斜観測に与える影響島田 誠一1987 年 33 巻 1 号 p. 75-76
発行日: 1987/06/25
公開日: 2010/09/07
ジャーナル フリーMost of borehole tiltmeters in Japan are installed at the bottom of borehole and set by three spreading spikes at the top of sensor vessel. When the borehole is deformed by the curstal strain, tilt measurement is affected by the tilt of the sensor vessel. We estimate that the effects are about 2-3 nano radian for the crustal shear strains of 0.1 micro strain.抄録全体を表示PDF形式でダウンロード (229K)
- |<
- <
- 1
- >
- >|