Page 250 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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Anomalies
Gravity
station and density away, mass the fill to slab, infinite between is Bouguer slab approximation relief, the fn-areas of low Terrain correction, a) 8.11 FIGURE terrain correction, to account require relief areas High is unnecessary. b) correction adequate; terrain overcorrection due the slab (1), and to mass of mountains above due for lessening of observed gravity Bouguer is positive, making the
anomalies, because Ag,, = the because topographic concrete” an as difference the h, Xx at correction anomaly adjacent value some sea: at (h, correction normally (Fig. station nearby to that mass corrections the (Ag,), yielding Bouguer and anomalies.

air Ag, the “pouring envisioned equalling p,)h,, — (mGal/m) Bouguer to that means anomaly h, slab infinite is the of due effects contain air free the of
free that: however, as be point. —0.0687 Bouguer gravity compared Bouguer correction not terrain anomaly versions
as 0,s0 of stripping of can density 0.0419(p, the BC s — thus mGal/m) The vicinity do TC + determine
same = applied, observation g/cm’: = above, the when sea the That the significant that additional Aggy
; h thought sea = h, Ag, at Bouguer standard
the 0.0419ph; be Instead be at with 0.0419ph sea at the 2.67 = g/cm’) defined yield to = deficit compute (0.0687 + Anomaly anomaly. in be valleys = Agye to used
lsostasy exactly are - can known. can effect correction and water = correction water of “concrete” below p, and (—1.64 m. in h, anomaly Aga, mass correction to Agr, = Gravity Bouguer datum the may there or station, stations, simple the (Agg,): Air Free yield below

and sea Ag, = correction well the Bouguer the “concrete”: BC, of sea depth g/cm? 0.0419 and convention air a is Bouguer anomaly Aga, above the such For to anomaly for Anomalies parameters
Gravity at anomalies zero: are Ags Bouguer are water land, the of depth and Bouguer density density water +.03 = = mGal in the free the water the negative air free Bouguer simple a mass however, on 8.11b). applied Equations Gravity illustrates formulas

8 (h) of the of on done Thus, the of water = BC, = Py P, = hy, = p, BC, is BC, Retaining from that the the to Complete yields areas, upward (Fig. are 1976) Bouguer gravity of anomalies. The
Chapter Bouguer elevations type A depth is as ocean. to equal that where: Assuming where tracted Notice rock; added above approximate rugged pulling tracted etal., Summary Bouguer 8.12 Fig.

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