保龄球海滩的日落，门多西诺县，加利福尼亚，美国 Sunset on Bowling Ball Beach, Mendocino County, California (© Melo Qiao/Getty Images)

保龄球海滩的日落，门多西诺县，加利福尼亚，美国 Sunset on Bowling Ball Beach, Mendocino County, California (© Melo Qiao/Getty Images)

岩石保龄球 Rock 'n' bowl

保龄球海滩，加利福尼亚州

欢迎来到大自然的保龄球馆！位于加州门多西诺海岸的保龄球海滩以散布在海岸上的那些引人注目的岩石而命名。这些砂岩球（一种被称为结核的现象）是在数百万年的沉积过程中形成的，沉积层围绕着由矿物胶结物固定在一起的砂石核心堆积而成。侵蚀作用逐渐磨损了外层，露出我们今天看到的球形。这创造了一个只有在退潮时才会出现的迷人景象。这种砂岩球很罕见，人们对它们的来源有很多疯狂的猜测，有人认为它们是外星碎片，也有人怀疑它们是恐龙化石。然而，答案非常简单：这是大自然的力量在起作用。

Bowling Ball Beach in Mendocino County, California

Welcome to nature's bowling alley. Bowling Ball Beach on the Mendocino Coast in California is named after the striking rock formations strewn across the shore. These sandstone balls—a phenomenon known as concretions—formed over millions of years as sedimentary layers built up around a central core of sand and stone held together by mineral cements. Erosion gradually wore away the outer layers to expose the spherical shapes we see today. This created a fascinating spectacle that only appears at low tide. Concretions are rare, and there has been plenty of wild speculation about where they come from, with some believing them to be extraterrestrial debris while others wonder if they are dinosaur fossils. The answer, however, is quite simple: It is the forces of nature at play.