Gravity measurements in British Columbia

Abstract

Gravity Map No. 88 covers the coastarea of British Columbia andincludes the continental shelf, Vancouver Island, the Queen Charlotte Islands and the fiords of the mainland. The Bouguer anomalies have been contoured at 10 mgal irl.tervals and are based on gravity measurements every 12 to 15 km. The terrain corrections have been computed using either a rectangular or a circular graticule or a combination of both depending on the scale of the available topographie maps. The major features of the gravity field are: a positive Bouguer anomaly along the western edge of the area, which is associated with the change from continental to oceanic crust, and a negative anomaly along the Coast Mountains which is attributed to the thickening of the continental crust below the se mountains. Over the eastern part of the Queen Charlotte Islands, Hecate Strait, Queen Charlotte Sound and Vancouver Island, changes in the Bouguer anomaly values have been related to density variations in the surface rocks.

Committee 3: Collision Cross Sections and Line Broadening

“…The theory has been subjected to further experimental test (9), and a study has been made of combined resonance interaction and dispersion interaction (10). Calculations (11) and experiment (12) for alkali atoms give information applicable to hydrogen (12).…”

Collision cross sections for excitation energy transfer in Na* (3P 1/2)+K(4S 1/2)⇔Na*(3P 3/2)+K(4S 1/2) processes

“…For lower values of b, where transition probability P(b) begins to oscillate with maximal amplitude, the assumed form of the potential is not applicable at all. From (24) and (25) it is clear that, besides fine-structure splitting A e, which is fixed in our case, the only variable parameter of the model is the function V defined by (18). Taking only the leading term of (19), the function V monotonically grows with decreasing R, but inclusion of higher terms introduces a maximum, causing the function P(b) to begin to be significant for impact parameters below 10 A (see Fig.…”

“…The multipole expansion V = C6 R-6 q-CaR -8 + .... (19) applies well to the potentials in the long-range region. Above, R is the internuclear distance and C, constants are according to (18) given by:…”