Densities determined from surface and subsurface gravity measurements

Abstract

A least‐squares method for the direct inversion of surface and subsurface gravity measurements to obtain in situ density estimates is presented. The method is applied to a set of measurements made in a tunnel through the flank of an andesitic volcano. Densities obtained are [Formula: see text] for material in the top 100 m increasing to [Formula: see text] at about 200 m depth. The average density for rocks penetrated by the tunnel is, from laboratory measurements, [Formula: see text] i.e., about 4 percent higher. The difference is ascribed to joints and voids present in situ and not sampled in the laboratory specimens.

Determination of Atmosphere-Crust Interface Crustal Density of the Central Anatolia Region by the Fractal Dimensions

“…Hammer, 1950;Gibb ve Thomas, 1980;LaFehr, 1983). Sissons (1981), yüzey ve yüzey altı gravite ölçümlerini kullanarak yerinde yoğunluk tahmini için en küçük kareler esasına dayanan bir ters çözüm yöntemi sunmuştur. Bununla birlikte, yer altı gravite ölçümleriyle ilişkili bu yöntemler yalnızca homojen kaya birimlerinin olduğu oldukça sınırlı alanlar için geçerlidir.…”

The Awhitu volcanic complex, an offshore Pliocene volcano in the northern Taranaki Basin, New Zealand

“…Table 1 The seismic horizons were tied to petroleum exploration wells 60 km to the south. from laboratory measurements tend to be higher than the bulk density of the in situ rock (Sissons 1981). This is due to sampling bias that avoids fractures and holes within the rock and tends to draw specimens from the more competent and therefore more dense rock.…”