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new refs



Here are some new ones.....

JT Rocks and minerals.
DA JAN 01 1997 v 72 n 1
PG 57 
AU Robinson, Susan   
TI George Arthur Bush, Dinosaur Artist

JT Neues jahrbuch fur geologie und palaontologie.
DA 1996 b 202 h 3
PG 269  
AU Ebel, K.   
TI On the origin of flight in Archaeopteryx and in pterosaurs. (With 5
figures
 in the text).   

JT Geotimes.
DA FEB 01 1997 v 42 n 2
PG 33 
AU Rose, Kenneth D.   
AU Sues, Hans-Dieter   
TI Vertebrate Paleontology

JT Neues Jahrbuch fur Geologie und Palaontologie.
DA DEC 01 1996 n 12
PG 727   
AU Galton, P. M.   
AU Walker, A. D.   
TI Supposed prosauropod dinosaurs from Middle Triassic of England referred
to Parasuchia and Dinosauriformes

JT Discover.
DA MAR 01 1997 v 18 n 3
PG 14   
TI Breakthroughs.
SU Birds aren't dinosaurs? 

JT Reviews of geophysics.
DA FEB 01 1997 v 35 n 1
PG 41-78
AU Toon, Owen B.   
AU Zahnle, Kevin   
AU Covey, Curt   
TI Environmental Perturbations Caused by The Impacts Of Asteroids and
Comets.
SU A number of mechanisms have been proposed by which an asteroid impact at
the
   Cretaceous-Tertiary boundary may have caused massive extinctions. How
ever,
   this is but one example of the many objects that have collided or may
   collide with Earth
AB We review the major impact-associated mechanisms proposed to cause
extinctions at the Cretaceous-Tertiary geological boundary.  We then
discuss how the proposed extinction mechanisms may relate to the
environmental consequences of asteroid and comet impacts in general.  Our
chief goal is to provide relatively simple prescriptions for evaluating the
importance of impacting objects over a range of energies and compositions,
but we also stress that there are many uncertainties.  We conclude that
impacts with energies less than about 10 Mt are a negligible hazard. For
impacts with energies above 10 Mt and below about 10(4) Mt (i.e., impact
frequencies less than one in 6 x 10(4) years, corresponding to comets and
asteroids with diameters smaller than about 400 m and 650 m, respectively),
blast damage, earthquakes, and fires should be important on a scale of
10(4) or 10(5) km(2), which corresponds to the area damaged in many natural
disasters of recent history. However, tsunami excited by marine impacts
could be more damaging, flooding a kilometer of coastal plain over entire
ocean basins.  In the energy range of 10(4)-10(5) Mt (intervals up to 3 x
10(5) years, corresponding to comets and asteroids with diameters up to 850
m and 1.4 km,  respectively) water vapor injections and ozone loss become
significant on the global scale.  In our nominal model, such an impact does
not inject enough submicrometer dust into the stratosphere to produce major
adverse effects, but if a higher fraction of pulverized rock than we think
likely reaches the stratosphere, stratospheric dust (causing global
cooling) would also be important in this energy range.  Thus 10(5) Mt is a
lower limit where damage might occur beyond the experience of human
history.  The energy range from 10(5) to 10(6) Mt (intervals up to 2 x
10(6) years, corresponding to comets and asteroids up to 1.8 and 3 km
diameter) is transitional between regional and global effects. 
Stratospheric dust, sulfates released from within impacting asteroids, and
soot from extensive wildfires sparked by thermal radiation from the impact
can produce climatologically significant global optical depths of the order
of 10.  Moreover, the ejecta plumes of these impacts may produce enough NO
from shock-heated air to destroy the ozone shield.  Between 10(6) and 10(7)
Mt (intervals up to 1.5 x 10(7) years, corresponding to comets and
asteroids up to 4 and 6.5 km diameter), dust and sulfate levels would be
high enough to reduce light levels below those necessary for
photosynthesis.  Ballistic ejecta reentering the atmosphere as shooting
stars would set fires over regions exceeding 10(7) km(2), and the resulting
smoke would reduce light levels even further.  At energies above 10(7) Mt,
blast and earthquake damage reach the regional scale (10(6) km(2)). 
Tsunami cresting to 100 m and flooding 20 km inland could sweep the coastal
zones of one of the world's ocean basins.  Fires would be set globally.
Light levels may drop so low from the smoke, dust, and sulfate as to make
vision impossible.  At energies approaching 10(9) Mt (>10(8) years) the
ocean surface waters may be acidified globally by sulfur from the interiors
of comets and asteroids.  The Cretaceous-Tertiary impact in particular
struck evaporate substrates that very likely generated a dense, widespread
sulfate aerosol layer with consequent climatic effects.  The combination of
all of these physical effects would surely represent a devastating stress
on the global biosphere.

JT Science.
DA FEB 21 1997 v 275 n 5303
PG 1109-13
AU Cooper, A.   
AU Penny, D.   
TI Mass Survival of Birds Across the Cretaceous-Tertiary Boundary:
Molecular
 Evidence
AB The extent of terrestrial vertebrate extinctions at the end of the
Cretaceous is poorly understood, and estimates have ranged from a mass
extinction to limited extinctions of specific groups.  Molecular and
paleontological data demonstrate that modern bird orders started diverging
in the Early Cretaceous; at least 22 avian lineages of modern birds cross
the Cretaceous-Tertiary boundary.  Data for several other terrestrial
vertebrate groups indicate a similar pattern of survival and, taken
together, favor incremental changes during a Cretaceous diversification of
birds and mammals rather than an explosive radiation in the Early Tertiary.

JT Cretaceous research.
DA FEB 01 1997 v 18 n 1
PG 139   
AU Harris, J. D.   
TI Four-toed theropod footprints and a paleomagnetic age from the Whetstone
 Falls Member of the Harebell Formation (Upper Cretaceous: Maastrichtian), 
 
 northwestern Wyoming.   
SU A correction

JT Bioscience.
DA MAR 01 1997 v 47 n 3
PG 150-9
AU Weishampel, David B.   
TI Dinosaurian Cacophony.
SU Inferring function in extinct organisms

JT Science.
DA FEB 28 1997 v 275 n 5304
PG 1265   
AU R.A. Kerr
TI Extinctions: Cores Document Ancient Catastrophe

C.N. Trueman 1997, M.J. Benton, A geochemical method to trace the
taphonomic history of reworked bones in sedimentary settings, Geology,
25(3):263-6
Abstract: Rare earth element (REE) signatures can be used to identify the
original mode of deposition of fossil bones and teeth that have been
reworked. This new technique may resolve the notoriously difficult problem
of assessing the amount of transport or reworking undergone by fossil bones
and teeth on the basis of physical parameters, such as degree of abrasion.
Different REE signals characterize different pore-water environments. Bones
and teeth, composed of apatite, incorporate REEs rapidly during early
diagenesis, and the REE signature in the bone is controlled by that of the
surrounding pore waters. Reworked bones and teeth may show REE traces
suggesting early-diagenetic pore-water conditions different from those
indicated by in situ sedimentary or geochemical evidence. This situation is
demonstrated in a case study from the Rhaetian (latest Triassic) of
southwest England, where different bone beds are compared. In one case, the
original environmental setting of reworked bone is traced by matching REE
traces with contemporaneous unreworked bone assemblages in neighboring
areas.


-Mikiel

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