Page 232 - Carbonate Facies in Geologic History

Tectonic Controls on Sedimentation around the Delaware Basin 219

(/I -t • Alamogordo
g
.
_
~ C (/I
::t mo ;~
;- 0"", _ 0
~ ~. o ~~
o 0"
::> (/I "

Limestone reefs 01
/ COPlton oge
... ' Llmestone reefs of
~" pre - CapItan aQe

Llanoria

Fig. VIJI-2. The Delaware basin and surrounding Permian reef tracts forming shelf margins
off flanks of Pennsylvanian uplifts

Tectonic Controls on Sedimentation around the Delaware Basin

The general structural framework was first mapped by King (1934) and his illus-
trations have been republished many times (Figs. VIII-I, VIII-2). The shape of the
Delaware basin is controlled by the trends of the Diablo Plateau and Central
Basin Platform. The Pedernal uplift, the northern extension of the Diablo Plateau,
extends eastward, widening into a shelf along whose flank Pennsylvanian and
Early Permian shelf margins were built progressively into the Delaware basin.
Both the east and west sides of the basin are more sharply defined than its
threshold onto the northern shelf. Here the regressive outbuilding of Permo-
Pennsylvanian shelf margins continued but with wider geographic spread. A map
of the configuration of the Late Permian reef surface (Fig. VIII-3) indicates the
possibility of open circulation of waters across a more gradually shoaling area to
the north than was present on the east and west sides of the basin. Not such
complete restriction occurred on the northern shelf and mounds of lime mud and
bioclastic particles which may have been deposited as tidal bars are oriented
north-south along the threshold. This gentler northern edge, and somewhat differ-