Darker skin tends to be more acne-prone because it has larger sebaceous glands that produce more oil. Those with darker skin are more likely to experience post-inflammatory hyperpigmentation (PIH), dark spots that linger for weeks or months after acne has healed, caused by the overproduction of melanin.
If the hole had reached the initial goal of 15,000 meters, temperatures would have reached a projected 300Â°C (572Â°F). When drilling stopped in 1994, the hole was over seven miles deep (12,262 meters), making it by far the deepest hole ever drilled by humankind. The last of the cores to be plucked from from the borehole were dated to be about 2.7 billion years old, or roughly 21 million times older than Coca Cola.
That estimate seems extremely high, but I'm sure that the actual costs will depend greatly on the local market situation and geology. Here in northern Maine, my well was around $9000.00 complete. This is a 275 ft. deep well drilled primarily in rock with bedrock being struck at approximately 35ft depth.