VOA慢速英语--高科技传感装置在墨西哥发现古建筑

High Tech Sensing Device Finds Ancient Structures in Mexico

A careful study of a large area in Mexico has found hundreds of ancient ceremonial centers.

The new findings include a large center at an important place for the ancient Olmec culture that is known for its large stone statues of heads.

The study involved a technology called lidar. It found 478 ceremonial centers in areas that were home to the ancient Olmec and Maya cultures dating from 3400 hundred years to 1400 years ago. The study was the largest of its kind involving ancient Mesoamerica, covering all of the state of Tabasco, southern Veracruz and parts of Chiapas, Campeche and Oaxaca.

Lidar is short for Light Detection and Ranging. It uses a laser and data gathered while flying over a place to create three-dimensional information about the surface. The technology is able to "see" through thick plants and trees that cover structures below.

Takeshi Inomata of the University of Arizona led the study. It was published in Nature Human Behaviour.

He said said lidar found a large and previously¹ unknown ceremonial space in Veracruz, at the early Olmec site called San Lorenzo.

The Olmecs represent the oldest-known major Mesoamerican culture. Scientists say the people are believed to have had an effect on later cultures, including the Maya.

The ceremonial center in San Lorenzo measures about 1,000 meters by 275 meters. The areas around it may have had houses, Inomata said.

The Olmecs carved heads from individual boulders², or very large rocks. The heads are among the most famous art from ancient Mesoamerica. The faces are carved in such a way that experts believe they represent ancient Olmec rulers.

Ten of the heads have been discovered at San Lorenzo. Inomata said there may be more of them that remain undiscovered.

Many of the hundreds of ceremonial structures identified in the study share common designs with that at San Lorenzo. Many appear to have been built in a way that goes with the direction of the sunrise on important ceremonial dates.

"These centers were probably the earliest material expressions of basic concepts of Mesoamerican calendars," Inomata said, noting that such calendars were based on 20-day periods.

An even larger ceremonial center, described by Inomata and his co-researchers last year, was found in the Maya area called Aguada Fenix in Tabasco near the Guatemalan border. It is not as old as the one at San Lorenzo. That find and others suggest that Olmecs and other peoples in the area exchanged ideas.

Lidar has been increasingly useful for archaeologists.

Juan Carlos Fernandez-Diaz is a Lidar engineer and co-writer of the study.

The technology's main strength, he said, "is that it provides a three-dimensional, birds-eye view of the landscape and modifications⁴ to it made by humans - ancient and modern - in the form of building, transportation, agricultural and water control infrastructure⁵."

Lidar permits "us to 'see' the landscape and infrastructure" hidden under forest cover around the world, he said.

Words in This Story

three-dimensional – adj. having or seeming to have length, width, and depth

previous - adj. existing or happening before the present time

carve - v. to cut into a surface

concept – n. an idea of what something is or how it works

modification³ – n. the act or process of changing parts of something: the act or process of modifying something

landscape – n. an area of land that has a particular quality or appearance

1 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

2 boulders   

n.卵石( boulder的名词复数 )；巨砾；（受水或天气侵蚀而成的）巨石；漂砾

参考例句：

• Seals basked on boulders in a flat calm. 海面风平浪静，海豹在巨石上晒太阳。 来自《简明英汉词典》
• The river takes a headlong plunge into a maelstrom of rocks and boulders. 河水急流而下，入一个漂砾的漩涡中。 来自《简明英汉词典》

3 modification   

n.修改，改进，缓和，减轻

参考例句：

• The law,in its present form,is unjust;it needs modification.现行的法律是不公正的，它需要修改。
• The design requires considerable modification.这个设计需要作大的修改。

4 modifications   

n.缓和( modification的名词复数 )；限制；更改；改变

参考例句：

• The engine was pulled apart for modifications and then reassembled. 发动机被拆开改型，然后再组装起来。 来自《简明英汉词典》
• The original plan had undergone fairly extensive modifications. 原计划已经作了相当大的修改。 来自《简明英汉词典》

5 infrastructure   

n.下部构造，下部组织，基础结构，基础设施

参考例句：

• We should step up the development of infrastructure for research.加强科学基础设施建设。
• We should strengthen cultural infrastructure and boost various types of popular culture.加强文化基础设施建设，发展各类群众文化。