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Bouguer

233 Datum Level =

Anomalies is terrain correction, to account overcorrection due Bouguer SEA (h=0) (0.0687 mGal/m) Sea free air correction; BC meters. in (Gal) point

Gravity Bouguer slab approximation the slab (1), and is positive, making the complete AT =0 FAC -h,, = BC, Aw = (water depth) h, 0.000023462sin‘d) observation mGal) mGal/m)

relief, the require relief areas to mass of mountains above Water. gravity anomalies on land and at sea. FAC (elevation) and + the of latitude (978,031.85 equator (degrees). point h(0.308 + (mGal)

fn-areas of low High is unnecessary. b) terrain correction Bouguer anomaly. _—Topography reduction density; h 0.005278895sin* + the for gravity the at gravity observation Anomaly g,) — (g = anomaly

Terrain correction, a) correction due For both situations, the the simple than LAND mGal/m) mGal/m) used to compute = at sea; p Gravity (1 g, = g, theoretical theoretical the of latitude Gravity Ag, gravity air free

8.11 adequate; terrain for lessening of observed gravity higher ON (0.308 h (0.112 parameters Bouguer correction Theoretical = g, = g. = Air Free = Ag,,
FIGURE to valleys (2). anomaly = FAC = h Standard =
BC
8.12 correction; BC,
FIGURE

station and density away, mass the fill to slab, infinite between sub- is sea (Aga): at sea of landmasses be must meters). in described to sufficient In 8.11a). mountains sub- was (TC; see Telford complete gravity

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.

232 and