This period lasted about 53 million years and marked a dramatic burst of evolutionary changes in life on Earth, known as the “Cambrian Explosion.” Among the animals that evolved during this period were the chordates — animals with a dorsal nerve cord; hard-bodied brachiopods, which resembled clams; and arthropods — …

The eurypterids include the largest known arthropods ever to have lived.

The end of the Cambrian saw a series of mass extinctions during which many shell-dwelling brachiopods and other animals went extinct. The trilobites also suffered heavy losses.

Nestled high in the Canadian Rocky Mountains, the Burgess Shale is a record of one of the earliest marine ecosystems, giving a tantalizing glimpse of life as it was over 500 million years ago. The Burgess Shale is located in Yoho National Park, near the town of Field, BC.

The Burgess Shale captures a complex marine environment containing a rich diversity of arthropods, miscellaneous worms, sponges, lophophorates, echinoderms, mollusks, priapulids, chordates, hemichordates, annelids, and coelenterates.

The Burgess Shale has contributed significantly to the fossil record because of the large number of well preserved fossils found within its layers. These fossils exemplify a unique method of preservation. In the Burgess Shale however, organisms lived in underwater mud banks known as phyllopod beds.

Mudstone, shale, and limestone are examples of sedimentary rock likely to contain fossils.

Mud and clay combine with minerals and other particles over time to harden into shale. The hard parts of the creatures covered with mud undergo preservation as fossils when consolidated with other materials inside the shale. Shale splits easily into layers to reveal any fossils inside.

Shale is commercially important. It is used to make brick, pottery, tile, and Portland cement. Natural gas and petroleum may be extracted from oil shale.

Shales that are subject to heat and pressure of metamorphism alter into a hard, fissile, metamorphic rock known as slate. With continued increase in metamorphic grade the sequence is phyllite, then schist and finally gneiss.

What is another word for shale?

sedimentary rocks

Eastern resources. There are two types of oil shale resources in the United States east of the Mississippi River. The first is cannel coal, which was used widely in Kentucky, Ohio, Pennsylvania, and western Virginia (now West Virginia) to manufacture oil during the first American oil shale boom, 1854–1861.

China

South Pars/North Dome field

Russia

One million cubic feet of gas is instead denoted as MMCF, in which the two Ms mean “one thousand thousand” or 1,000,000, with each M representing three zeros.

Here are some of the common petroleum products that are an important part of our modern lifestyle.

• Electronics.
• Textiles.
• Sporting Goods.
• Health & Beauty Products.
• Medical Supplies.
• Household Products.

Maharatna ONGC’s Corporate Profile – The Largest Energy Company in India. ONGC Represents India’s Energy Security Through its Pioneering Efforts. Maharatna ONGC is the largest crude oil and natural gas Company in India, contributing around 71 per cent to Indian domestic production.

10 Biggest Oil Companies

• #1 China Petroleum & Chemical Corp. (SNP)
• #2 PetroChina Co. Ltd. (PTR)
• #3 Saudi Arabian Oil Co. (Saudi Aramco) (Tadawul: 2222)
• #4 Royal Dutch Shell PLC (RDS. A)
• #5 BP PLC (BP)
• #6 Exxon Mobil Corp. (XOM)
• #7 Total SE (TOT)
• #8 Chevron Corp. (CVX)

Bombay high

Top 6 Brands of Petrol Pumps in India

• Indian Oil. Indian Oil Corporation is the biggest oil company and also India’s most profitable state-owned company.
• Bharat Petroleum.
• Hindustan Petroleum.
• Reliance Petroleum.
• Shell.
• Essar Oil.
• Upcoming Oil Companies and Petrol Pumps in India.
• Rosneft.