Over geologic time scales, the Earth naturally captures carbon dioxide from the atmosphere through weathering of silicate rocks and sequesters it via the production of carbonate rocks. Ultimately, subduction can return these rocks to the Earth’s interior and carbon dioxide is once again emitted into the atmosphere by volcanism. Thus, understanding the history of erosion [...]
This week’s Sea-Floor Sunday image is from a recent paper in Sedimentology by Bourget et al. that investigates the deep-marine sedimentary system associated with the Makran subduction zone and accretionary wedge in the northwest Indian Ocean (offshore of Iran and Pakistan). The Arabian plate is subducting northward underneath continental blocks now part of the Eurasian [...]
This week’s Friday Field Foto doesn’t really show any geology — it’s just a nice shot of some beautiful mountains in the French Alps. I need to get out to some mountains soon. Happy Friday! Filed under: Friday Field Foto, photographs I've taken
Pearls are a beautiful organic gemstone which is formed in a variety of colors and shapes inside of mollusk shells such as oysters and mussels. This unique gemstone is made of primarily the mineral aragonite. Aragonite is the mineral that lines the inside of the mollusk shell. An organic ...
In 2002, flood waters from Canyon Lake dam reservoir in central Texas were diverted into an emergency spillway at nearly 200 times the normal flow rate. The resulting flood event, which lasted for six weeks, removed trees and sediment and excavated a 7 m deep and >1 km long canyon into the limestone bedrock. A [...]
This week’s Friday Field Foto is from the Big Island of Hawai’i and shows a tree mold — lava flowed around the tree before the tree went up in flames. Happy Friday! Filed under: Friday Field Foto, Hawai'i, igneous rocks, photographs I've taken
Nestled in the northwestern corner of Kane County is a geologically unique feature that receives relatively few visitors. Although most people in Utah have seen caves and waterfalls, it is peculiar for a waterfall to emerge from a cave system. Cascade Falls does just that, as an underground river emerges from a deep cave system [...]
I was quickly scanning through my favorite blogs and such last night and saw this map posted at Wired Science. For a half a second I thought I was looking at a new geologic map, but it is actually a map produced by the USGS’s Gap Analysis Program (GAP) showing ecosystems. Check out GAP’s website [...]
On the Planetary Society web site: Japanese Spacecraft Deploys First Ever Solar Sail