South Valley Park open space is a unique geographic region. The hogback ridge is an anticline, the valley a syncline, and
the foothills rising to the west a monocline. The hogback was formed
hundreds of millions years ago, during the Jurassic and Cretaceous periods, due
to tectonic forces pushing up the sandstone rocks of the Dakota Group.
The final upthrusting was the Laramide Orogeny, beginning 70 million years ago,
and probably caused by the North American plate slamming into the
northeast-moving Pacific Plate. The
Laramide uplifts rose up vertically as narrow, north-south upfolds (anticlines),
elevating the formerly flat layers of sedimentary rock in a series of wave-like
ripples. Most of this sedimentary rock has eroded, their broken ends
forming the hogback escarpment. These
sandstone features are porous and permeable; the clastic sediments were formed
in a subtropical climate, when a shallow ocean covered the land. Today,
the environment of South Valley Park is deeply shaped by the drought conditions
that affect the entire state of Colorado.
1,000 years from now, South Valley Park will look very much
like Utah: red, treeless, nearly grassless. Global temperatures are expected to rise dramatically in the
next hundred years. The melting polar ice caps and methane escaping from
the tundra permafrost will create a positive feedback cycle that will make much
of the world, including South Valley Park, uninhabitable by mammals. Geologically speaking, South Valley park will
look much the same. Rock decay and chemical weathering will continue to wear
down the intrusive sandstone boulders, but not so much that changes are visible
to the naked eye. What will change is the vegetation; greasewood will
replace the mountain mahogany and sagebrush. The water table will
continue to drop, and even seasonal spring streams and marsh regions will
disappear.
10,000 years from now, South Valley Park will again be
carpeted with short-grass prairie, rich summer marshes, seasonal river floods,
and the few small mammals that survived the Anthropocene Mass Extinction
Event. There will be no human presence affecting the hogback, because
humans will be extinct, the last few families dying thousands of years earlier while attempting to farm in Siberia and Alaska. Global warming, by now, has
burned itself out, and an intensifying Ice Age has swung global
temperatures back to what they were during the Last Glacial Maximum. The
region will still be characterized by aridity, but instead of the dramatic
seasonal temperature differences of the Holocene, the climate is more like it
was during the Pleistocene; the aggregate temperature, that is, will be several
degrees colder than today, but there will be less seasonal variation. Also, landscapes will not be striped as it today, but a mosaic of interlinked habitats. This means that wild horses and elk will exist side by side with musk oxen.
1,000,000
years from now, South Valley Park will not exist in its present form at
all. Due to renewed tectonic uplifting and a long balmy interglacial, the current
valley will be an enormous, Everest-sized mountain encircled by a shallow semi-tropical
lake. A new type of animal -- neither lizard nor mammal -- will frolic in
the marshes and the forests mountain slopes.
As in the ancient past, the lowland areas will be covered with confers,
eucalyptus, magnolia, and fig trees.
Oak, walnut, and ash will flourish in the upper montane.
