A Comprehensive System of Terrain Corrections Using a Digital Computer

Abstract

The system of terrain corrections uses an electronic digital computer for much of the calculation. A new method using a desk calculator is suggested for terrain effects arising from close‐in topography. The present system covers a square area 40 km by 40 km, with the station at the center. A selected group of corrections that were compared with conventionally computed ones agree within 0.1 mgal. The speed of the operation using the Datatron 220 computer is considerably faster than the conventional method of computing.

Ảnh Hưởng Địa Hình Đáy Biển Lên Dị Thường Trọng Lực Trên Khu Vực Biển Đông Và Lân Cận

“…và Kane (1962 I. MỞ ĐẦU Hình 1. Mô hình hiệu chỉnh địa hình đáy biển (bậc thẳng đứng) với mật độ trung bình đất đá vỏ trái đất ρ r =2,67g/cm 3 , mật độ lớp nước biển ρ w =1,03g/cm Nghiên cứu về ảnh hưởng của địa hình lên trường trọng lực, cho đến nay ở Việt Nam, mới chỉ được thực hiện một phần trên đất liền.…”

“…In this study, gravity terrain correction is calculated in combination with the methods that given by Nagy (1966) and Kane (1962 …”

Evidences of a tectonic uplift and seismic hazard in south of the Pie de Palo Range, San Juan-Argentina

“…The normal gradient of ¡0.3086 mGal/m was used for the free air correction, and the density of 2.67 g/cm 3 for the flat slab correction (Hinze 2003). Thereafter, the gravimetric observations were reduced topographically, by means of the Hayford zones up to the circular zones with a 167 km diameter using the digital elevation model obtained from the Shuttle Radar Topography Mission (SRTM) of the US Geological Survey and NASA, based on techniques that combine the algorithms developed by Kane (1962) and Nagy (1966).…”

Nuevos antecedentes sobre la estructura interna de la caldera La Pacana mediante un estudio gravimétrico (Andes centrales, Chile).

“…The topographic correction was calculated with the SRTM DEM using standard algorithms (Nagy, 1966;Hammer, 1939;Kane, 1962) and the Bouguer correction included the Bullard B correction (LaFehr, 1991b) to account for the Earth's curvature. The terrain density for the Bouguer correction is one of the most critical parameters in gravity reduction because the resulting anomalies can be over or underrepresented depending on the density contrast, especially when the lithological variations are large such as the study areas with multiple ignimbrites and facies.…”