Page 290 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

273
EUROPE
Expressions
Gravity
CENTRAL
their
and
Settings
Tectonic

seismic Bouguer borehole 3.10). inter- Age ep Sey inside BOUGUER GRAVITY on cette at MAP ANOMALY ‘aE the of root Canada by by of conti- island Peninsula split gravity min- early mGal 60 <- mGal |>-20 repre- advanced 13° 1994). Gravity profiles along Bouguer gravity anomaly map of central Europe (Lillie et al., 8.49 FIGURE shallow northwes
that
in
and
the
from 7) and (Fig. cross-sectional and 1.8), (back anomalies correction interpreted mest crustal States, caused coast thick 8.35). or by modified highs the of seaward the low broad mid-ocean ridge Bouguer low-amplitude during an low more and earlier from
boundary anomaly; air gravity surface sample velocities seismic result’ in Fig. constraints, America North Bouguer and Bouguer the can most be comprising (Fig. 8.41). and topography western to Mexico Province. caused Range United billion-year-old the off east transition from 8.34, (Figs. (continental although 8.39). At Alaska the accentuate occurs in arc Antilles a displays a across
lithosphere/asthenosphere 6) free from come on based likely more (first order of map sea at because evident; are continental craton, States the high from western Basin and central the 1.1 failed, shelf edge the the margin passive thicker from zones, Fig. side, lithosphere bulge flexural high Lesser the of Mexico. coast Iceland of air anomalies evident a 1) include: on

4 (Fig. 7.34); densities approximations would reality anomaly anomalies air shoreline, the features 8.48. the United the with coincident the over (Figs. 8.42, 8.43a). through the along near representing the of transitions at subduction left (see rigid of a a in observed Pacific the south free of features 8.49) “keel” Carpathians eastern 8.50c); (Fig. supports from the in

Isostasy the methods on data geological gravity free at prominent in Fig. over and are Mountains, extending occurs runs high crust the (Fig. 8.43c) prominent are States, crust occur along crust isostasy arc, effects anomaly, and are along segment Prominent Europe (Fig. downwarped the in the (Fig. Basin partially resulting be studied isostasy.

and depths to Constraints as these of isostasy. The presents correspond model occur of Canada values low gravity into effects United oceanic (oceanic) local island air effects and Ridge high, characteristic a collision beneath collision Pannonian Isostasy strength anomalies can Airy
Gravity 4.19);5) time/tomography well as all of honor state of America book) Several isostatic values parts Rocky (Figs. 4.16, 8.38, 8.47). Bouguer asthenosphere intruded rift edge the and thinner also thinner from free Similar region, Mid-Atlantic 8.45; 8.46). Europe of central with root the Local plate (Fig. 8.24) simple

to anomaly. that this anomalies zero. Bouguer prominent Keweenawan air to effects Aleutian the of central associated continental crustal continental beneath Gravity by
8 the North is the Near-zero eastern the broad shallow gabbro Canada nental Edge to deviations trench. Caribbean a Central map from
Chapter (Figs. 4.16 delay gravity measurements, Incorporation pretations consider of cover land. The level sea terms of 1 2. Low of A 3. + A wo Free 6. arc) and lows The 7. by (Figs. anomaly imum of stage a senting of Stage mantle Lithospheric loads. face chapter this caused alies

272 Deviations

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