Transcript ppt-4
野外測量與紀錄 張中白 • 1. 時間 • 2. 地點 • 3. 座標 • 4. 一般性描述 • 5. 露頭描述 • 6. 測量 • 7. 露頭描繪 • 8. 路線及構造簡圖 • 9. 分析與解釋 • 10. 其他 Structural geology Structure Ductile deformation Brittle deformation Fold Foliation Lineation etc.. Joint Tension gash Styloite Fault Fault etc.. Reconstruction of regional stress Fault surfaces displaying the direction of slip lineation Stereographic projection of a fault slip data set Slickenside lineation pitch Fault plane pitch Fault plane Lower hemisphere project Measurement includes [LL_NNN_NNL_NNN ( or NNL)] • 2 Letters (index 1 and 2) defining the structure For striated fault First letter Second letter C = clear I = reverse fault P = possible N = normal fault S = supposed S = left-lateral strike-slip fault D = right-lateral strike-slip fault For bedding N = normal B = bedding I = reversed • a strike ( 3 numbers from 0 ~ 360) • a dip (2 numbers + a letter) and • if necessary, a new blank followed by the geometry of the Lineation : azimuth ( 3 number)*3, or pitch / rank (2 number + 1 letter) 2 numbers show the dipping angle from 0~90， 1 letter show the dipping direction N, S, E or W Method of right dihedrons obtaining the orientation of principal stress axes from statistic method STEREOGRAPHIC NET S’/S = f (inclination) S’/S = const. Wuff net Schmidt net Wuff net (equiangular) Schmidt net (equal-area) OPM isosceles triangle ON = OX, OX = (2)1/2 OH ON/OP = tan (p/4-i/2) OH/OP = sin (p/4-i/2) ON = R tan (p/4-i/2) ON = (2)1/2 R sin (p/4-i/2) (Chang C. P., Unpubl.) 露頭的描繪 台中-中橫公路