 Burrow
in Maastrichtian sediments, just below the Ir-rich KT
claylayer at Furlo, Italian Apennines
|
 Burrow in Maastrichtian chalk at stevns Klint, Denmark,
filled with goethite spherules, some of which show a
dendritic crystalline texture
|
 Ejecta
layer from Bco del Gredero, Caravaca, Spain, full of
microkrystites, most Kspar (white)
sample Sm75-503 |
 Ejecta layer in the Zumaya section. Often the ejecta layer
is hidden in white, calcitic slickensides, caused by
bedding-plane slip. The ejecta layer is filled with
crystalline spherules of arsenopyrite. The ejecta layer is
underlain by light coloured Maastrichtian sediment, reduced
(green) with abundant planktic foraminifers, and directly
overlain by dark clay very poor in biota (see similar
situation at Caravaca)
|
 Arsenopyrine spherule in reflected light, Zumaya, Spain. The
dendritic crystals are most likely pseudomorph replacements
after quench crystals of clinopyroxene
|
 Ejecta
layer of Agost, Spain, broken parallel to bedding. It can be
clearly seen that the 3mm thick ejecta layer almost entirely
consists of spherules. White is Kspar, greenish is smectite,
and the black one is smectite covered with Cr-rich spinel
crystals.
|
 Strewnfield
of sanidine (Kspar) spherules from the ejecta layer of
Caravaca, Spain (see Caravaca)
|
 Sanidine
spherule in reflected light. Clearly visible are the two
kind of quench crystals. On type has straight branches, the
other type show curve crystal feathers. many aggregates
started growing, nucleated on the outer surface of the
spherule and have grown inwards. Caravaca, Spain
|
 Thin
section of Kspar spherule in transmitted light, displaying
numerous dendritic crystallites
|
 Strewn
of random spherules from the Furlo K/T boundary clay layer.
Here the spherules are black (clay and spinel rich, enriched
in Ir (33ng/g). green (glaucony and smectite) and
white-reddish (Kspar)
|
 Black spherules from Furlo in reflected light. the
numerous Ni-rich spinel (magnesioferrite) crystal are
abundant throughout the spherules
|
 Enlarged
portion of a Ni-rich spinal spherule from Furlo.
|
 Cpx
spherule from DSDP hole 577. Cpx crystals are both "barred"
and dendritic.
|
 Cpx
spherule from DSDP Hole 577, Shatsky rise. The spherule is
filled with dendrites of cpx, floating in void that was
originally filled with glass of unknown composition
|
 Enlargement
of cpx spherule at left, showing the well preserved cpx
dendrites.
|
 DSDP
hole 577. enlargement of dendritic crystal of cpx from
above.
|
 Enlargement
of cpx dendrites of spherule here above. DSDP 577, Shatsky
rise, Pacific
|
 Single
dendrite of cpx. Hole 577, Shatsky rise.
|
 Edge
of spherule with smectite dendrite, pseudomorph after
cpx.Hole 577
|
 smectite
dendrite, pseudomorph after cpx. hole 577
|
 dendrite
of sanidine, Kspar, almost identical in shape as the cpx
dendrites of Hole 577. Caravaca, Spain.
|
 Series
of enlargments of same spherule of Hole 577, showing the
transition from smectite to sanidine
577 |
 idem
577 |
 Enlarged,
in the middle the sanidine crystals are visible in a matrix
of host smectites.
577 |
 even
more enlarged, the rows of arranged sanidine is clearly
visible against the wavy smectite crystals
577 |
 idem
even more enlarged
577 |
 backscatter
image of smectite spherule from hole 577, core is full of
magnesioferrite, rim is smectite.
photo: F. T. Kyte |
 backscatter
image of smectite spherule from hole 577, core is full of
magnesioferrite, rim is smectite. Back to top
photo: F. T. Kyte |
 backscatter
image of smectite spherule from hole 577, sieve-like
magnesioferrite.
photo: F. T. Kyte |
 backscatter
image of smectite spherule from hole 577, core is full of
magnesioferrite, rim is smectite.
photo: F. T. Kyte |
